MQTT Class
Properties Methods Events Config Settings Errors
A lightweight, fully-featured MQTT client implementation.
Class Name
IPWorksIoT_MQTT
Procedural Interface
ipworksiot_mqtt_open(); ipworksiot_mqtt_close($res); ipworksiot_mqtt_register_callback($res, $id, $function); ipworksiot_mqtt_get_last_error($res); ipworksiot_mqtt_get_last_error_code($res); ipworksiot_mqtt_set($res, $id, $index, $value); ipworksiot_mqtt_get($res, $id, $index); ipworksiot_mqtt_do_config($res, $configurationstring); ipworksiot_mqtt_do_connect($res); ipworksiot_mqtt_do_connectto($res, $host, $port); ipworksiot_mqtt_do_disconnect($res); ipworksiot_mqtt_do_doevents($res); ipworksiot_mqtt_do_interrupt($res); ipworksiot_mqtt_do_publishdata($res, $topic, $qos, $data); ipworksiot_mqtt_do_publishmessage($res, $topic, $qos, $message); ipworksiot_mqtt_do_reset($res); ipworksiot_mqtt_do_restoresession($res, $statedata); ipworksiot_mqtt_do_savesession($res); ipworksiot_mqtt_do_subscribe($res, $topicfilter, $qos); ipworksiot_mqtt_do_unsubscribe($res, $topicfilter);
Remarks
The MQTT class provides a lightweight, fully-featured MQTT client implementation with support for versions 3.1.1 and 5.0. The class supports plaintext and TLS-enabled connections over both standard TCP and WebSockets.
Connecting
Connecting to an MQTT server is easy; in the simplest case, set the ClientId property and call the ConnectTo method, passing it the server's hostname and port number.When connecting to an MQTT server, the class sends the following information:
- The values of the ClientId, CleanSession, and KeepAliveInterval properties.
- The value of the User property (if non-empty).
- The value of the Password property (if non-empty).
- The values of the WillTopic and WillMessage properties and the WillQOS and WillRetain configuration settings.
- MQTT 5 specific values from ClientTopicAliasMax, SessionExpInterval, ConnectProperties and WillProperties.
If CleanSession is True, check the SessionPresent configuration setting once connected to determine whether the server actually had any session state saved.
Refer to CleanSession, SaveSession, and RestoreSession for more information about MQTT sessions and session state persistence; refer to WillTopic, WillMessage, WillQOS, and WillRetain for more information about MQTT Wills.
Basic Connection Example
mqtt1.ClientId = "testClient";
mqtt1.CleanSession = true;
mqtt1.KeepAliveInterval = 30;
mqtt1.WillTopic = "wills/" + mqtt1.ClientId;
mqtt1.WillMessage = mqtt1.ClientId + " was disconnected ungracefully!";
mqtt1.ConnectTo("mqtt.test-server.com", 1883);
Topic Subscriptions
The Subscribe and Unsubscribe methods are used to subscribe to and unsubscribe from topics.When subscribing, pass one or more topic filters and QoS levels to indicate the topics to subscribe to and the desired QoS level(s). Topic filters may contain wildcards in order to match multiple topics on the server.
Subscribe Examples
// Subscribed event handler.
mqtt1.OnSubscribed += (s, e) => {
if (e.ResponseCode <= 2)
Console.WriteLine("Subscribed to " + e.TopicFilter + " at QoS " + e.QOS + ".");
else
Console.WriteLine("Failed to subscribe to " + e.TopicFilter + ".");
};
// Basic, subscribe to some topic filters, all at the same QoS level.
mqtt1.Subscribe("home,home/floor1/+/temperature,home/floor2/#", 2);
// A bit more advanced, subscribe to the same topic filters, but at different QoS levels.
mqtt1.Config("TopicQOSArray=1,2,2");
// The 0 is ignored here since we've specified individual QoS values explicitly.
mqtt1.Subscribe("home,home/floor1/+/temperature,home/floor2/#", 0);
After subscribing to topics, any messages received will cause the MessageIn, and potentially also the MessageAck, events to fire. Refer to those events for more information about processing steps for inbound messages.
When unsubscribing, pass the exact same topic filter that was used to subscribe.
Unsubscribe Example
// Unsubscribe from topic filters; have to use the exact same strings as before. If this
// was to be called after calling the code example shown for the Subscribe() method, we
// would still be subscribed to the "home" topic filter.
mqtt1.Unsubscribe("home/floor1/+/temperature,home/floor2/#");
Refer to Subscribe and Unsubscribe for more information about subscriptions and topic filters.
Publishing Messages
To publish messages to topics, use the PublishMessage and PublishData methods.PublishMessage is used to publish a message with a string payload, while PublishData is used to publish a message with a raw data payload. Both also accept the name of a topic to publish to, and a QoS level at which to publish.
Publish Examples
// Publish a simple string-based message.
mqtt1.PublishMessage("/home/floor1/security/camera2", 1, "Cat detected!");
// Publish a raw data message.
byte[] catPicture = ...;
mqtt1.PublishData("/home/floor1/security/camera2", 1, catPicture);
Refer to PublishData and PublishMessage for more information about message publishing and processing steps for outbound messages, as well as topic naming.
MQTT 5 Notes
MQTT 5 is similar to v3.1.1, with a few changes and several new features. Major differences include:
- The Clean Session flag functionality is divided into two properties to allow for finer control over session state data: the Clean Start flag (see CleanSession) and the new SessionExpInterval.
- All response packets (CONNACK, PUBACK, PUBREC, PUBREL, PUBCOMP, SUBACK, UNSUBACK, DISCONNECT) now contain a reason code describing why operations succeeded or failed. See MessageAck, Subscribed, Unsubscribed, and DisconnectReasonCode for details.
- The Request / Response pattern is formalized by the addition of the ResponseTopic. Additional properties such as correlation data and be specified via OutgoingMessageProperties and ConnectProperties.
- New subscription features: Shared Subscriptions, Subscription Options, and SubscriptionIdentifier (see Subscribe for details).
- Topic Aliases can be sent by both client and server to refer to topic filters by shorter numerical identifiers in order to save bandwidth (see TopicAlias, ServerTopicAliasMax and ClientTopicAliasMax).
- Servers can communicate what features it supports in ConnAckProperties.
- More: message expiration (OutgoingMessageProperties), Receive Maximums and Maximum Packet Sizes (ConnectProperties and ConnAckProperties), and a Will Delay interval (WillProperties) are all supported.
Property List
The following is the full list of the properties of the class with short descriptions. Click on the links for further details.
CleanSession | Determines whether a clean session is used once connected. |
ClientId | A string that uniquely identifies this instance of the class to the server. |
Connected | Triggers a connection or disconnection. |
FirewallAutoDetect | This property tells the class whether or not to automatically detect and use firewall system settings, if available. |
FirewallType | This property determines the type of firewall to connect through. |
FirewallHost | This property contains the name or IP address of firewall (optional). |
FirewallPassword | This property contains a password if authentication is to be used when connecting through the firewall. |
FirewallPort | This property contains the transmission control protocol (TCP) port for the firewall Host . |
FirewallUser | This property contains a user name if authentication is to be used connecting through a firewall. |
IncomingMessageCount | The number of records in the IncomingMessage arrays. |
IncomingMessageContentType | String describing the content of the message. |
IncomingMessageCorrelationData | Used by the sender of the request message to identify which request the response message is for when it is received. |
IncomingMessageDuplicate | Whether or not this message's Duplicate flag is set. |
IncomingMessageMessage | This message's raw data payload. |
IncomingMessageMessageExpInterval | The lifetime of the message in seconds specified by the sender. |
IncomingMessagePacketId | This message's packet Id. |
IncomingMessagePayloadFormatIndicator | Indicates whether the payload is unspecified bytes or UTF-8 Encoded character data. |
IncomingMessageQoS | This message's QoS level. |
IncomingMessageResponseTopic | String used as the topic name for a response message. |
IncomingMessageRetained | Whether or not this message's Retain flag is set. |
IncomingMessageState | This message's current state. |
IncomingMessageSubscriptionIdentifiers | A comma separated list of any SubscriptionIdentifiers associated with any client subscription(s) that caused this message to be delivered. |
IncomingMessageTopic | This message's topic. |
IncomingMessageTopicAlias | An integer used to identify the topic instead of the full topic filter in order to reduce the size of the publish packet. |
KeepAliveInterval | The maximum period of inactivity the class will allow before sending a keep-alive packet. |
LocalHost | The name of the local host or user-assigned IP interface through which connections are initiated or accepted. |
LocalPort | The TCP port in the local host where the class binds. |
OutgoingMessageCount | The number of records in the OutgoingMessage arrays. |
OutgoingMessageContentType | String describing the content of the message. |
OutgoingMessageCorrelationData | Used by the sender of the request message to identify which request the response message is for when it is received. |
OutgoingMessageDuplicate | Whether or not this message's Duplicate flag is set. |
OutgoingMessageMessage | This message's raw data payload. |
OutgoingMessageMessageExpInterval | The lifetime of the message in seconds specified by the sender. |
OutgoingMessagePacketId | This message's packet Id. |
OutgoingMessagePayloadFormatIndicator | Indicates whether the payload is unspecified bytes or UTF-8 Encoded character data. |
OutgoingMessageQoS | This message's QoS level. |
OutgoingMessageResponseTopic | String used as the topic name for a response message. |
OutgoingMessageRetained | Whether or not this message's Retain flag is set. |
OutgoingMessageState | This message's current state. |
OutgoingMessageSubscriptionIdentifiers | A comma separated list of any SubscriptionIdentifiers associated with any client subscription(s) that caused this message to be delivered. |
OutgoingMessageTopic | This message's topic. |
OutgoingMessageTopicAlias | An integer used to identify the topic instead of the full topic filter in order to reduce the size of the publish packet. |
Password | A password if authentication is to be used. |
ReadyToSend | Indicates whether the class is ready to send data. |
RemoteHost | The address of the remote host. Domain names are resolved to IP addresses. |
RemotePort | The port of the MQTT server (default is 1883). The default port for SSL is 8883. |
SSLAcceptServerCertEncoded | This is the certificate (PEM/base64 encoded). |
SSLCertEncoded | This is the certificate (PEM/base64 encoded). |
SSLCertStore | This is the name of the certificate store for the client certificate. |
SSLCertStorePassword | If the type of certificate store requires a password, this property is used to specify the password needed to open the certificate store. |
SSLCertStoreType | This is the type of certificate store for this certificate. |
SSLCertSubject | This is the subject of the certificate used for client authentication. |
SSLEnabled | Whether TLS/SSL is enabled. |
SSLProvider | This specifies the SSL/TLS implementation to use. |
SSLServerCertEncoded | This is the certificate (PEM/base64 encoded). |
Timeout | A timeout for the class. |
User | A username if authentication is to be used. |
Version | The MQTT protocol version that the class will conform to. |
WillMessage | The message that the server should publish in the event of an ungraceful disconnection. |
WillTopic | The topic that the server should publish the WillMessage to in the event of an ungraceful disconnection. |
Method List
The following is the full list of the methods of the class with short descriptions. Click on the links for further details.
Config | Sets or retrieves a configuration setting. |
Connect | Connects to the remote host. |
ConnectTo | Connects to the remote host. |
Disconnect | This method disconnects from the remote host. |
DoEvents | Processes events from the internal message queue. |
Interrupt | Interrupt the current action and disconnects from the remote host. |
PublishData | Publishes a message with a raw data payload. |
PublishMessage | Publishes a message with a string payload. |
Reset | Reset the class. |
RestoreSession | Restores session state data. |
SaveSession | Saves session state data. |
Subscribe | Subscribes the class to one or more topic filters. |
Unsubscribe | Unsubscribes the class from one or more topic filters. |
Event List
The following is the full list of the events fired by the class with short descriptions. Click on the links for further details.
Connected | This event is fired immediately after a connection completes (or fails). |
ConnectionStatus | This event is fired to indicate changes in the connection state. |
Disconnected | This event is fired when a connection is closed. |
Error | Information about errors during data delivery. |
Log | Fires once for each log message. |
MessageAck | Fired when an incoming or outgoing message has completed all acknowledgment steps. |
MessageIn | Fired when an incoming message has been received and/or fully acknowledged. |
MessageOut | Fired when an outgoing message has been sent and/or fully acknowledged. |
ReadyToSend | Fired when the class is ready to send data. |
SSLServerAuthentication | Fired after the server presents its certificate to the client. |
SSLStatus | Shows the progress of the secure connection. |
Subscribed | Fires for each topic filter subscription the server acknowledges. |
Unsubscribed | Fires when the server has acknowledged an unsubscribe request. |
Config Settings
The following is a list of config settings for the class with short descriptions. Click on the links for further details.
AutoReconnect | Whether to automatically attempt to reconnect in the event of a connection error. |
ClientTopicAliasMax | The maximum value the client will accept for a topic alias sent by the server. |
ConnAckProperties | JSON string containing the properties returned in the CONNACK packet. |
ConnectionTimeout | How long to wait for a connection attempt to succeed. |
ConnectProperties | JSON string specifying properties to be included in the CONNECT packet. |
DisconnectProperties | JSON string containing DISCONNECT packet properties. |
DisconnectReasonCode | Code describing the reason the client or server closed the connection. |
Duplicate | Whether to set the Duplicate flag when publishing a message. |
IncomingUserPropCount | The size of the IncomingUserPropName and IncomingUserPropValue arrays. |
IncomingUserPropName[i] | The name of the user property at index i. |
IncomingUserPropValue[i] | The value of the user property at index i. |
LogLevel | The level of detail that is logged. |
OutgoingMessageProperties | JSON string specifying properties to be included in the PUBLISH packet. |
OutgoingPacketId | The packet Id of the last message published. |
OutgoingUserPropCount | Controls the size of the OutgoingUserPropName and OutgoingUserPropValue configuration arrays. |
OutgoingUserPropName[i] | The name of the User Property at index i. |
OutgoingUserPropValue[i] | The value of the User Property at index i. |
RepublishInterval | How many seconds to wait before republishing unacknowledged messages. |
ResponseTopic | Topic name for a response message. |
Retain | Whether to set the Retain flag when publishing a message. |
SendCustomPacket | Sends a packet constructed using the supplied hex byte string. |
ServerTopicAliasMax | The highest value that the Server will accept as a Topic Alias sent by the Client. |
SessionExpInterval | The length of time in seconds the client and server should store session state data after the connection is closed. |
SessionPresent | When connecting with CleanSession disabled, indicates whether the server actually had any previous session data stored. |
SessionStateFile | File to use for saving and restoring session data. |
SubscriptionIdentifier | A numeric subscription identifier included in SUBSCRIBE packet which will be returned with messages delivered for that subscription. |
TopicAlias | Value that is used to identify the Topic instead of using the Topic Name in order to reduce packet size. |
TopicDelimiter | The string to use as a delimiter in a topic filter list string. |
TopicNLArray | List of No Local option flags for subscription topic filters. |
TopicQOSArray | Comma-separated list of topic filter QoS values to use when subscribing. |
TopicRAPArray | List of Retain As Published option flags for subscription topic filters. |
TopicRHArray | List of Retain Handling option values for subscription topic filters. |
WillProperties | JSON string specifying will properties to be included in the CONNECT packet. |
WillQOS | The QoS value to use for the Will message. |
WillRetain | Whether the server should retain the Will message after publishing it. |
ConnectionTimeout | Sets a separate timeout value for establishing a connection. |
FirewallAutoDetect | Tells the class whether or not to automatically detect and use firewall system settings, if available. |
FirewallHost | Name or IP address of firewall (optional). |
FirewallPassword | Password to be used if authentication is to be used when connecting through the firewall. |
FirewallPort | The TCP port for the FirewallHost;. |
FirewallType | Determines the type of firewall to connect through. |
FirewallUser | A user name if authentication is to be used connecting through a firewall. |
KeepAliveInterval | The retry interval, in milliseconds, to be used when a TCP keep-alive packet is sent and no response is received. |
KeepAliveTime | The inactivity time in milliseconds before a TCP keep-alive packet is sent. |
Linger | When set to True, connections are terminated gracefully. |
LingerTime | Time in seconds to have the connection linger. |
LocalHost | The name of the local host through which connections are initiated or accepted. |
LocalPort | The port in the local host where the class binds. |
MaxLineLength | The maximum amount of data to accumulate when no EOL is found. |
MaxTransferRate | The transfer rate limit in bytes per second. |
ProxyExceptionsList | A semicolon separated list of hosts and IPs to bypass when using a proxy. |
TCPKeepAlive | Determines whether or not the keep alive socket option is enabled. |
TcpNoDelay | Whether or not to delay when sending packets. |
UseIPv6 | Whether to use IPv6. |
LogSSLPackets | Controls whether SSL packets are logged when using the internal security API. |
OpenSSLCADir | The path to a directory containing CA certificates. |
OpenSSLCAFile | Name of the file containing the list of CA's trusted by your application. |
OpenSSLCipherList | A string that controls the ciphers to be used by SSL. |
OpenSSLPrngSeedData | The data to seed the pseudo random number generator (PRNG). |
ReuseSSLSession | Determines if the SSL session is reused. |
SSLCACertFilePaths | The paths to CA certificate files on Unix/Linux. |
SSLCACerts | A newline separated list of CA certificate to use during SSL client authentication. |
SSLCheckCRL | Whether to check the Certificate Revocation List for the server certificate. |
SSLCheckOCSP | Whether to use OCSP to check the status of the server certificate. |
SSLCipherStrength | The minimum cipher strength used for bulk encryption. |
SSLEnabledCipherSuites | The cipher suite to be used in an SSL negotiation. |
SSLEnabledProtocols | Used to enable/disable the supported security protocols. |
SSLEnableRenegotiation | Whether the renegotiation_info SSL extension is supported. |
SSLIncludeCertChain | Whether the entire certificate chain is included in the SSLServerAuthentication event. |
SSLKeyLogFile | The location of a file where per-session secrets are written for debugging purposes. |
SSLNegotiatedCipher | Returns the negotiated cipher suite. |
SSLNegotiatedCipherStrength | Returns the negotiated cipher suite strength. |
SSLNegotiatedCipherSuite | Returns the negotiated cipher suite. |
SSLNegotiatedKeyExchange | Returns the negotiated key exchange algorithm. |
SSLNegotiatedKeyExchangeStrength | Returns the negotiated key exchange algorithm strength. |
SSLNegotiatedVersion | Returns the negotiated protocol version. |
SSLSecurityFlags | Flags that control certificate verification. |
SSLServerCACerts | A newline separated list of CA certificate to use during SSL server certificate validation. |
TLS12SignatureAlgorithms | Defines the allowed TLS 1.2 signature algorithms when SSLProvider is set to Internal. |
TLS12SupportedGroups | The supported groups for ECC. |
TLS13KeyShareGroups | The groups for which to pregenerate key shares. |
TLS13SignatureAlgorithms | The allowed certificate signature algorithms. |
TLS13SupportedGroups | The supported groups for (EC)DHE key exchange. |
AbsoluteTimeout | Determines whether timeouts are inactivity timeouts or absolute timeouts. |
FirewallData | Used to send extra data to the firewall. |
InBufferSize | The size in bytes of the incoming queue of the socket. |
OutBufferSize | The size in bytes of the outgoing queue of the socket. |
BuildInfo | Information about the product's build. |
CodePage | The system code page used for Unicode to Multibyte translations. |
LicenseInfo | Information about the current license. |
MaskSensitive | Whether sensitive data is masked in log messages. |
ProcessIdleEvents | Whether the class uses its internal event loop to process events when the main thread is idle. |
SelectWaitMillis | The length of time in milliseconds the class will wait when DoEvents is called if there are no events to process. |
UseInternalSecurityAPI | Tells the class whether or not to use the system security libraries or an internal implementation. |
CleanSession Property (IPWorksIoT_MQTT Class)
Determines whether a clean session is used once connected.
Object Oriented Interface
public function getCleanSession(); public function setCleanSession($value);
Procedural Interface
ipworksiot_mqtt_get($res, 1 ); ipworksiot_mqtt_set($res, 1, $value );
Default Value
true
Remarks
This property determines whether or not the class should instruct the server to use a clean session when it connects. (Note that this property must be set to the desired value before calling Connect.)
By default, CleanSession is true, so the server will discard any state data previously associated with the current ClientId once the class has connected successfully. In addition, the server will not save any state data when the class disconnects.
Setting CleanSession to False before connecting will cause the server to re-associate any previously stored state data for the current ClientId. The server will also save any state data that exists when the class is disconnected.
The server-side session state consists of:
- whether a session is present (see SessionPresent),
- client subscriptions (including subscription identifiers in MQTT 5),
- QoS 1 and 2 messages sent to the client pending transmission or completed acknowledgment (and optionally pending QoS 0 messages),
- QoS 2 messages received from the client but not completely acknowledged, and
- the SessionExpInterval (in MQTT 5).
Note that retained messages are not deleted as a result of a session ending, but are not part of the session state.
Client-Side Session State
When setting CleanSession to False, it is important that the RestoreSession method be used to load any previously saved (client-side) session data from a previous session before calling Connect. (Successful calls to RestoreSession will automatically set CleanSession to False.)
Similarly, once disconnected, save the string returned by SaveSession for later use. The saved session information may be used when connecting with CleanSession set to False at a later time.
The client-side session state consists of:
- QoS 1 and QoS 2 messages which have been sent to the Server, but have not been completely acknowledged, and
- QoS 2 messages which have been received from the Server, but have not been completely acknowledged.
Refer to SaveSession and RestoreSession for more information.
MQTT 5 Notes
In MQTT 5, the "Clean Session" flag from v3.1.1 is split into a "Clean Start" flag indicating that the server should discard previously saved session data from this connection, and a SessionExpInterval controlling the length of time the server should preserve the session data after disconnection.
In MQTT 5, this property acts only as the "Clean Start" flag. It determines whether or not the class should instruct the server to discard any previously stored session data associated with the current ClientId and start a new clean session.
For more information on session expiration in MQTT 5, see the SessionExpInterval config. Setting CleanSession to True in v3.1.1 is equivalent to setting CleanSession to True AND setting SessionExpInterval to 0 in MQTT 5.
As with MQTT 3.1.1, it is important for the client to save and restore its own session data on connection and disconnection depending on the value of CleanSession, and to manage its preservation depending on SessionExpInterval.
This property is not available at design time.
Data Type
Boolean
ClientId Property (IPWorksIoT_MQTT Class)
A string that uniquely identifies this instance of the class to the server.
Object Oriented Interface
public function getClientId(); public function setClientId($value);
Procedural Interface
ipworksiot_mqtt_get($res, 2 ); ipworksiot_mqtt_set($res, 2, $value );
Default Value
''
Remarks
The ClientId string is used by the server to uniquely identify each client that is connected to it. In MQTT 5, when the SessionExpInterval config is set to a positive value, the server will also associate it with any session state data that needs to be saved for the length of time specified when the class is disconnected.
If ClientId is empty when Connect is called, the class's behavior depends on value of CleanSession. If CleanSession is True, the class will automatically generate a unique value for ClientId before connecting. If CleanSession is False, the class fails with an error.
This property is not available at design time.
Data Type
String
Connected Property (IPWorksIoT_MQTT Class)
Triggers a connection or disconnection.
Object Oriented Interface
public function getConnected(); public function setConnected($value);
Procedural Interface
ipworksiot_mqtt_get($res, 3 ); ipworksiot_mqtt_set($res, 3, $value );
Default Value
false
Remarks
This property triggers a connection or disconnection. Setting this property to True makes the class attempt to connect to the host identified by the RemoteHost property. If successful, after the connection is achieved the value of the property changes to True and the Connected event is fired.
Setting this property to False closes the connection.
By default the class will connect in plaintext. To enable SSL set SSLEnabled to True.
In addition, WebSocket connections are supported. To connect using WebSockets specify a hostname beginning with ws:// (plaintext) or wss:// (SSL). For instance, ws://test.mosquitto.org.
When connecting to an MQTT server, the class sends the following information:
- The values of the ClientId, CleanSession, and KeepAliveInterval properties.
- The value of the User property (if non-empty).
- The value of the Password property (if non-empty).
- The values of the WillTopic and WillMessage properties and the WillQOS and WillRetain configuration settings.
- MQTT 5 specific values from ClientTopicAliasMax, SessionExpInterval, ConnectProperties and WillProperties.
If CleanSession is True, check the SessionPresent configuration setting once connected to determine whether the server actually had any session state saved.
Refer to CleanSession, SaveSession, and RestoreSession for more information about MQTT sessions and session state persistence; refer to WillTopic, WillMessage, WillQOS, and WillRetain for more information about MQTT Wills.
Basic Connection Example
mqtt1.ClientId = "testClient";
mqtt1.CleanSession = true;
mqtt1.KeepAliveInterval = 30;
mqtt1.WillTopic = "wills/" + mqtt1.ClientId;
mqtt1.WillMessage = mqtt1.ClientId + " was disconnected ungracefully!";
mqtt1.RemoteHost = "mqtt.test-server.com";
mqtt1.RemotePort = 1883;
mqtt1.Connect();
This property is not available at design time.
Data Type
Boolean
FirewallAutoDetect Property (IPWorksIoT_MQTT Class)
This property tells the class whether or not to automatically detect and use firewall system settings, if available.
Object Oriented Interface
public function getFirewallAutoDetect(); public function setFirewallAutoDetect($value);
Procedural Interface
ipworksiot_mqtt_get($res, 4 ); ipworksiot_mqtt_set($res, 4, $value );
Default Value
false
Remarks
This property tells the class whether or not to automatically detect and use firewall system settings, if available.
Data Type
Boolean
FirewallType Property (IPWorksIoT_MQTT Class)
This property determines the type of firewall to connect through.
Object Oriented Interface
public function getFirewallType(); public function setFirewallType($value);
Procedural Interface
ipworksiot_mqtt_get($res, 5 ); ipworksiot_mqtt_set($res, 5, $value );
Default Value
0
Remarks
This property determines the type of firewall to connect through. The applicable values are as follows:
fwNone (0) | No firewall (default setting). |
fwTunnel (1) | Connect through a tunneling proxy. FirewallPort is set to 80. |
fwSOCKS4 (2) | Connect through a SOCKS4 Proxy. FirewallPort is set to 1080. |
fwSOCKS5 (3) | Connect through a SOCKS5 Proxy. FirewallPort is set to 1080. |
fwSOCKS4A (10) | Connect through a SOCKS4A Proxy. FirewallPort is set to 1080. |
Data Type
Integer
FirewallHost Property (IPWorksIoT_MQTT Class)
This property contains the name or IP address of firewall (optional).
Object Oriented Interface
public function getFirewallHost(); public function setFirewallHost($value);
Procedural Interface
ipworksiot_mqtt_get($res, 6 ); ipworksiot_mqtt_set($res, 6, $value );
Default Value
''
Remarks
This property contains the name or IP address of firewall (optional). If a FirewallHost is given, the requested connections will be authenticated through the specified firewall when connecting.
If this property is set to a Domain Name, a DNS request is initiated. Upon successful termination of the request, this property is set to the corresponding address. If the search is not successful, the class fails with an error.
Data Type
String
FirewallPassword Property (IPWorksIoT_MQTT Class)
This property contains a password if authentication is to be used when connecting through the firewall.
Object Oriented Interface
public function getFirewallPassword(); public function setFirewallPassword($value);
Procedural Interface
ipworksiot_mqtt_get($res, 7 ); ipworksiot_mqtt_set($res, 7, $value );
Default Value
''
Remarks
This property contains a password if authentication is to be used when connecting through the firewall. If FirewallHost is specified, the FirewallUser and FirewallPassword properties are used to connect and authenticate to the given firewall. If the authentication fails, the class fails with an error.
Data Type
String
FirewallPort Property (IPWorksIoT_MQTT Class)
This property contains the transmission control protocol (TCP) port for the firewall Host .
Object Oriented Interface
public function getFirewallPort(); public function setFirewallPort($value);
Procedural Interface
ipworksiot_mqtt_get($res, 8 ); ipworksiot_mqtt_set($res, 8, $value );
Default Value
0
Remarks
This property contains the transmission control protocol (TCP) port for the firewall FirewallHost. See the description of the FirewallHost property for details.
Note: This property is set automatically when FirewallType is set to a valid value. See the description of the FirewallType property for details.
Data Type
Integer
FirewallUser Property (IPWorksIoT_MQTT Class)
This property contains a user name if authentication is to be used connecting through a firewall.
Object Oriented Interface
public function getFirewallUser(); public function setFirewallUser($value);
Procedural Interface
ipworksiot_mqtt_get($res, 9 ); ipworksiot_mqtt_set($res, 9, $value );
Default Value
''
Remarks
This property contains a user name if authentication is to be used connecting through a firewall. If the FirewallHost is specified, this property and FirewallPassword properties are used to connect and authenticate to the given Firewall. If the authentication fails, the class fails with an error.
Data Type
String
IncomingMessageCount Property (IPWorksIoT_MQTT Class)
The number of records in the IncomingMessage arrays.
Object Oriented Interface
public function getIncomingMessageCount();
Procedural Interface
ipworksiot_mqtt_get($res, 10 );
Default Value
0
Remarks
This property controls the size of the following arrays:
- IncomingMessageContentType
- IncomingMessageCorrelationData
- IncomingMessageDuplicate
- IncomingMessageMessage
- IncomingMessageMessageExpInterval
- IncomingMessagePacketId
- IncomingMessagePayloadFormatIndicator
- IncomingMessageQoS
- IncomingMessageResponseTopic
- IncomingMessageRetained
- IncomingMessageState
- IncomingMessageSubscriptionIdentifiers
- IncomingMessageTopic
- IncomingMessageTopicAlias
This property is read-only and not available at design time.
Data Type
Integer
IncomingMessageContentType Property (IPWorksIoT_MQTT Class)
String describing the content of the message.
Object Oriented Interface
public function getIncomingMessageContentType($incomingmessageindex);
Procedural Interface
ipworksiot_mqtt_get($res, 11 , $incomingmessageindex);
Default Value
''
Remarks
String describing the content of the message. Defined by the sending and receiving application.
Valid only for MQTT 5.
The $incomingmessageindex parameter specifies the index of the item in the array. The size of the array is controlled by the IncomingMessageCount property.
This property is read-only and not available at design time.
Data Type
String
IncomingMessageCorrelationData Property (IPWorksIoT_MQTT Class)
Used by the sender of the request message to identify which request the response message is for when it is received.
Object Oriented Interface
public function getIncomingMessageCorrelationData($incomingmessageindex);
Procedural Interface
ipworksiot_mqtt_get($res, 12 , $incomingmessageindex);
Default Value
''
Remarks
Used by the sender of the request message to identify which request the response message is for when it is received.
Valid only for MQTT 5.
The $incomingmessageindex parameter specifies the index of the item in the array. The size of the array is controlled by the IncomingMessageCount property.
This property is read-only and not available at design time.
Data Type
String
IncomingMessageDuplicate Property (IPWorksIoT_MQTT Class)
Whether or not this message's Duplicate flag is set.
Object Oriented Interface
public function getIncomingMessageDuplicate($incomingmessageindex);
Procedural Interface
ipworksiot_mqtt_get($res, 13 , $incomingmessageindex);
Default Value
false
Remarks
Whether or not this message's Duplicate flag is set.
The $incomingmessageindex parameter specifies the index of the item in the array. The size of the array is controlled by the IncomingMessageCount property.
This property is read-only and not available at design time.
Data Type
Boolean
IncomingMessageMessage Property (IPWorksIoT_MQTT Class)
This message's raw data payload.
Object Oriented Interface
public function getIncomingMessageMessage($incomingmessageindex);
Procedural Interface
ipworksiot_mqtt_get($res, 14 , $incomingmessageindex);
Default Value
''
Remarks
This message's raw data payload.
The $incomingmessageindex parameter specifies the index of the item in the array. The size of the array is controlled by the IncomingMessageCount property.
This property is read-only and not available at design time.
Data Type
Binary String
IncomingMessageMessageExpInterval Property (IPWorksIoT_MQTT Class)
The lifetime of the message in seconds specified by the sender.
Object Oriented Interface
public function getIncomingMessageMessageExpInterval($incomingmessageindex);
Procedural Interface
ipworksiot_mqtt_get($res, 15 , $incomingmessageindex);
Default Value
0
Remarks
The lifetime of the message in seconds specified by the sender.
For outgoing messages, the value is useful for instructing the server to delete its copies of the message for any subscribers it has not been able to start delivery to.
For incoming messages, the value sent by the server is the lifetime specified by the sender minus the time the message has been waiting in the server.
Valid only for MQTT 5.
The $incomingmessageindex parameter specifies the index of the item in the array. The size of the array is controlled by the IncomingMessageCount property.
This property is read-only and not available at design time.
Data Type
Integer
IncomingMessagePacketId Property (IPWorksIoT_MQTT Class)
This message's packet Id.
Object Oriented Interface
public function getIncomingMessagePacketId($incomingmessageindex);
Procedural Interface
ipworksiot_mqtt_get($res, 16 , $incomingmessageindex);
Default Value
0
Remarks
This message's packet Id.
The $incomingmessageindex parameter specifies the index of the item in the array. The size of the array is controlled by the IncomingMessageCount property.
This property is read-only and not available at design time.
Data Type
Integer
IncomingMessagePayloadFormatIndicator Property (IPWorksIoT_MQTT Class)
Indicates whether the payload is unspecified bytes or UTF-8 Encoded character data.
Object Oriented Interface
public function getIncomingMessagePayloadFormatIndicator($incomingmessageindex);
Procedural Interface
ipworksiot_mqtt_get($res, 17 , $incomingmessageindex);
Default Value
0
Remarks
Indicates whether the payload is unspecified bytes or UTF-8 Encoded character data. Possible values are:
Value | Description |
0 | Payload is unspecified bytes |
1 | Payload is UTF-8 Encoded Character Data |
Valid only for MQTT 5.
The $incomingmessageindex parameter specifies the index of the item in the array. The size of the array is controlled by the IncomingMessageCount property.
This property is read-only and not available at design time.
Data Type
Integer
IncomingMessageQoS Property (IPWorksIoT_MQTT Class)
This message's QoS level.
Object Oriented Interface
public function getIncomingMessageQoS($incomingmessageindex);
Procedural Interface
ipworksiot_mqtt_get($res, 18 , $incomingmessageindex);
Default Value
0
Remarks
This message's QoS level. Possible values are:
Value | Description |
0 | At most once delivery |
1 | At least once delivery |
2 | Exactly once delivery |
The $incomingmessageindex parameter specifies the index of the item in the array. The size of the array is controlled by the IncomingMessageCount property.
This property is read-only and not available at design time.
Data Type
Integer
IncomingMessageResponseTopic Property (IPWorksIoT_MQTT Class)
String used as the topic name for a response message.
Object Oriented Interface
public function getIncomingMessageResponseTopic($incomingmessageindex);
Procedural Interface
ipworksiot_mqtt_get($res, 19 , $incomingmessageindex);
Default Value
''
Remarks
String used as the topic name for a response message.
Valid only for MQTT 5.
The $incomingmessageindex parameter specifies the index of the item in the array. The size of the array is controlled by the IncomingMessageCount property.
This property is read-only and not available at design time.
Data Type
String
IncomingMessageRetained Property (IPWorksIoT_MQTT Class)
Whether or not this message's Retain flag is set.
Object Oriented Interface
public function getIncomingMessageRetained($incomingmessageindex);
Procedural Interface
ipworksiot_mqtt_get($res, 20 , $incomingmessageindex);
Default Value
false
Remarks
Whether or not this message's Retain flag is set.
The $incomingmessageindex parameter specifies the index of the item in the array. The size of the array is controlled by the IncomingMessageCount property.
This property is read-only and not available at design time.
Data Type
Boolean
IncomingMessageState Property (IPWorksIoT_MQTT Class)
This message's current state.
Object Oriented Interface
public function getIncomingMessageState($incomingmessageindex);
Procedural Interface
ipworksiot_mqtt_get($res, 21 , $incomingmessageindex);
Default Value
0
Remarks
This message's current state.
Possible Outgoing Message States:
Value | Description |
0 | PUBLISH sent, waiting for PUBACK (QoS 1 only) |
1 | PUBLISH sent, waiting for PUBREC (QoS 2 only) |
2 | PUBREC received, sending PUBREL (QoS 2 only) |
3 | PUBREL sent, waiting for PUBCOMP (QoS 2 only) |
4 | Final acknowledgment received |
Possible Incoming Message States:
Value | Description |
5 | PUBLISH received, sending PUBACK (QoS 1 only) |
6 | PUBLISH received, sending PUBREC (QoS 2 only) |
7 | PUBREC sent, waiting for PUBREL (QoS 2 only) |
8 | PUBREL received, sending PUBCOMP (QoS 2 only) |
9 | Final acknowledgment sent |
The $incomingmessageindex parameter specifies the index of the item in the array. The size of the array is controlled by the IncomingMessageCount property.
This property is read-only and not available at design time.
Data Type
Integer
IncomingMessageSubscriptionIdentifiers Property (IPWorksIoT_MQTT Class)
A comma separated list of any SubscriptionIdentifiers associated with any client subscription(s) that caused this message to be delivered.
Object Oriented Interface
public function getIncomingMessageSubscriptionIdentifiers($incomingmessageindex);
Procedural Interface
ipworksiot_mqtt_get($res, 22 , $incomingmessageindex);
Default Value
''
Remarks
A comma separated list of any SubscriptionIdentifiers associated with any client subscription(s) that caused this message to be delivered.
This property is only applicable to incoming messages.
If SubscriptionIdentifier is set when subscribing, it will be included in any messages delivered by the broker for the topics specified in that packet.
See the Subscribe method for more details.
Valid only for MQTT 5.
The $incomingmessageindex parameter specifies the index of the item in the array. The size of the array is controlled by the IncomingMessageCount property.
This property is read-only and not available at design time.
Data Type
String
IncomingMessageTopic Property (IPWorksIoT_MQTT Class)
This message's topic.
Object Oriented Interface
public function getIncomingMessageTopic($incomingmessageindex);
Procedural Interface
ipworksiot_mqtt_get($res, 23 , $incomingmessageindex);
Default Value
''
Remarks
This message's topic.
MQTT 5 Notes:
If this value is empty, the IncomingMessageTopicAlias property holds the assigned alias for the topic.
If this value is not empty and IncomingMessageTopicAlias is non-zero,
The $incomingmessageindex parameter specifies the index of the item in the array. The size of the array is controlled by the IncomingMessageCount property.
This property is read-only and not available at design time.
Data Type
String
IncomingMessageTopicAlias Property (IPWorksIoT_MQTT Class)
An integer used to identify the topic instead of the full topic filter in order to reduce the size of the publish packet.
Object Oriented Interface
public function getIncomingMessageTopicAlias($incomingmessageindex);
Procedural Interface
ipworksiot_mqtt_get($res, 24 , $incomingmessageindex);
Default Value
0
Remarks
An integer used to identify the topic instead of the full topic filter in order to reduce the size of the publish packet.
If a non-zero topic alias is received, the client should establish a new topic alias mapping or use an existing mapping, depending on whether the IncomingMessageTopic string is empty.
For details on setting topic aliases for outgoing messages, see the TopicAlias configuration setting.
Valid only for MQTT 5.
The $incomingmessageindex parameter specifies the index of the item in the array. The size of the array is controlled by the IncomingMessageCount property.
This property is read-only and not available at design time.
Data Type
Integer
KeepAliveInterval Property (IPWorksIoT_MQTT Class)
The maximum period of inactivity the class will allow before sending a keep-alive packet.
Object Oriented Interface
public function getKeepAliveInterval(); public function setKeepAliveInterval($value);
Procedural Interface
ipworksiot_mqtt_get($res, 25 ); ipworksiot_mqtt_set($res, 25, $value );
Default Value
0
Remarks
The KeepAliveInterval, if set to a non-zero value, is the maximum number of seconds that the class will allow the connection to be idle before sending a PINGREQ (ping request) packet to the server. The value of KeepAliveInterval is sent to the server when Connect is called; it cannot be changed when the class is already connected.
MQTT servers are required to measure periods of inactivity for all clients who specify a non-zero KeepAliveInterval, and must disconnect them if they have not communicated within 1.5 times KeepAliveInterval.
Similarly, if the class doesn't receive a PINGRESP (ping response) packet within KeepAliveInterval seconds after sending a PINGREQ packet, it will disconnect from the server.
If KeepAliveInterval is set to 0 (default), keep-alive functionality is disabled entirely. In this case, the class will not send any PINGREQ packets, and the server is not required to close the connection due to inactivity.
Note that, regardless of keep-alive settings, the server is always free to disconnect clients it deems "unresponsive".
This property is not available at design time.
Data Type
Integer
LocalHost Property (IPWorksIoT_MQTT Class)
The name of the local host or user-assigned IP interface through which connections are initiated or accepted.
Object Oriented Interface
public function getLocalHost(); public function setLocalHost($value);
Procedural Interface
ipworksiot_mqtt_get($res, 26 ); ipworksiot_mqtt_set($res, 26, $value );
Default Value
''
Remarks
The LocalHost property contains the name of the local host as obtained by the gethostname() system call, or if the user has assigned an IP address, the value of that address.
In multi-homed hosts (machines with more than one IP interface) setting LocalHost to the value of an interface will make the class initiate connections (or accept in the case of server classs) only through that interface.
If the class is connected, the LocalHost property shows the IP address of the interface through which the connection is made in internet dotted format (aaa.bbb.ccc.ddd). In most cases, this is the address of the local host, except for multi-homed hosts (machines with more than one IP interface).
NOTE: LocalHost is not persistent. You must always set it in code, and never in the property window.
Data Type
String
LocalPort Property (IPWorksIoT_MQTT Class)
The TCP port in the local host where the class binds.
Object Oriented Interface
public function getLocalPort(); public function setLocalPort($value);
Procedural Interface
ipworksiot_mqtt_get($res, 27 ); ipworksiot_mqtt_set($res, 27, $value );
Default Value
0
Remarks
This property must be set before a connection is attempted. It instructs the class to bind to a specific port (or communication endpoint) in the local machine.
Setting this property to 0 (default) enables the system to choose an open port at random. The chosen port will be returned by the LocalPort property after the connection is established.
LocalPort cannot be changed once a connection is made. Any attempt to set this property when a connection is active will generate an error.
This property is useful when trying to connect to services that require a trusted port in the client side.
Data Type
Integer
OutgoingMessageCount Property (IPWorksIoT_MQTT Class)
The number of records in the OutgoingMessage arrays.
Object Oriented Interface
public function getOutgoingMessageCount();
Procedural Interface
ipworksiot_mqtt_get($res, 28 );
Default Value
0
Remarks
This property controls the size of the following arrays:
- OutgoingMessageContentType
- OutgoingMessageCorrelationData
- OutgoingMessageDuplicate
- OutgoingMessageMessage
- OutgoingMessageMessageExpInterval
- OutgoingMessagePacketId
- OutgoingMessagePayloadFormatIndicator
- OutgoingMessageQoS
- OutgoingMessageResponseTopic
- OutgoingMessageRetained
- OutgoingMessageState
- OutgoingMessageSubscriptionIdentifiers
- OutgoingMessageTopic
- OutgoingMessageTopicAlias
This property is read-only and not available at design time.
Data Type
Integer
OutgoingMessageContentType Property (IPWorksIoT_MQTT Class)
String describing the content of the message.
Object Oriented Interface
public function getOutgoingMessageContentType($outgoingmessageindex);
Procedural Interface
ipworksiot_mqtt_get($res, 29 , $outgoingmessageindex);
Default Value
''
Remarks
String describing the content of the message. Defined by the sending and receiving application.
Valid only for MQTT 5.
The $outgoingmessageindex parameter specifies the index of the item in the array. The size of the array is controlled by the OutgoingMessageCount property.
This property is read-only and not available at design time.
Data Type
String
OutgoingMessageCorrelationData Property (IPWorksIoT_MQTT Class)
Used by the sender of the request message to identify which request the response message is for when it is received.
Object Oriented Interface
public function getOutgoingMessageCorrelationData($outgoingmessageindex);
Procedural Interface
ipworksiot_mqtt_get($res, 30 , $outgoingmessageindex);
Default Value
''
Remarks
Used by the sender of the request message to identify which request the response message is for when it is received.
Valid only for MQTT 5.
The $outgoingmessageindex parameter specifies the index of the item in the array. The size of the array is controlled by the OutgoingMessageCount property.
This property is read-only and not available at design time.
Data Type
String
OutgoingMessageDuplicate Property (IPWorksIoT_MQTT Class)
Whether or not this message's Duplicate flag is set.
Object Oriented Interface
public function getOutgoingMessageDuplicate($outgoingmessageindex);
Procedural Interface
ipworksiot_mqtt_get($res, 31 , $outgoingmessageindex);
Default Value
false
Remarks
Whether or not this message's Duplicate flag is set.
The $outgoingmessageindex parameter specifies the index of the item in the array. The size of the array is controlled by the OutgoingMessageCount property.
This property is read-only and not available at design time.
Data Type
Boolean
OutgoingMessageMessage Property (IPWorksIoT_MQTT Class)
This message's raw data payload.
Object Oriented Interface
public function getOutgoingMessageMessage($outgoingmessageindex);
Procedural Interface
ipworksiot_mqtt_get($res, 32 , $outgoingmessageindex);
Default Value
''
Remarks
This message's raw data payload.
The $outgoingmessageindex parameter specifies the index of the item in the array. The size of the array is controlled by the OutgoingMessageCount property.
This property is read-only and not available at design time.
Data Type
Binary String
OutgoingMessageMessageExpInterval Property (IPWorksIoT_MQTT Class)
The lifetime of the message in seconds specified by the sender.
Object Oriented Interface
public function getOutgoingMessageMessageExpInterval($outgoingmessageindex);
Procedural Interface
ipworksiot_mqtt_get($res, 33 , $outgoingmessageindex);
Default Value
0
Remarks
The lifetime of the message in seconds specified by the sender.
For outgoing messages, the value is useful for instructing the server to delete its copies of the message for any subscribers it has not been able to start delivery to.
For incoming messages, the value sent by the server is the lifetime specified by the sender minus the time the message has been waiting in the server.
Valid only for MQTT 5.
The $outgoingmessageindex parameter specifies the index of the item in the array. The size of the array is controlled by the OutgoingMessageCount property.
This property is read-only and not available at design time.
Data Type
Integer
OutgoingMessagePacketId Property (IPWorksIoT_MQTT Class)
This message's packet Id.
Object Oriented Interface
public function getOutgoingMessagePacketId($outgoingmessageindex);
Procedural Interface
ipworksiot_mqtt_get($res, 34 , $outgoingmessageindex);
Default Value
0
Remarks
This message's packet Id.
The $outgoingmessageindex parameter specifies the index of the item in the array. The size of the array is controlled by the OutgoingMessageCount property.
This property is read-only and not available at design time.
Data Type
Integer
OutgoingMessagePayloadFormatIndicator Property (IPWorksIoT_MQTT Class)
Indicates whether the payload is unspecified bytes or UTF-8 Encoded character data.
Object Oriented Interface
public function getOutgoingMessagePayloadFormatIndicator($outgoingmessageindex);
Procedural Interface
ipworksiot_mqtt_get($res, 35 , $outgoingmessageindex);
Default Value
0
Remarks
Indicates whether the payload is unspecified bytes or UTF-8 Encoded character data. Possible values are:
Value | Description |
0 | Payload is unspecified bytes |
1 | Payload is UTF-8 Encoded Character Data |
Valid only for MQTT 5.
The $outgoingmessageindex parameter specifies the index of the item in the array. The size of the array is controlled by the OutgoingMessageCount property.
This property is read-only and not available at design time.
Data Type
Integer
OutgoingMessageQoS Property (IPWorksIoT_MQTT Class)
This message's QoS level.
Object Oriented Interface
public function getOutgoingMessageQoS($outgoingmessageindex);
Procedural Interface
ipworksiot_mqtt_get($res, 36 , $outgoingmessageindex);
Default Value
0
Remarks
This message's QoS level. Possible values are:
Value | Description |
0 | At most once delivery |
1 | At least once delivery |
2 | Exactly once delivery |
The $outgoingmessageindex parameter specifies the index of the item in the array. The size of the array is controlled by the OutgoingMessageCount property.
This property is read-only and not available at design time.
Data Type
Integer
OutgoingMessageResponseTopic Property (IPWorksIoT_MQTT Class)
String used as the topic name for a response message.
Object Oriented Interface
public function getOutgoingMessageResponseTopic($outgoingmessageindex);
Procedural Interface
ipworksiot_mqtt_get($res, 37 , $outgoingmessageindex);
Default Value
''
Remarks
String used as the topic name for a response message.
Valid only for MQTT 5.
The $outgoingmessageindex parameter specifies the index of the item in the array. The size of the array is controlled by the OutgoingMessageCount property.
This property is read-only and not available at design time.
Data Type
String
OutgoingMessageRetained Property (IPWorksIoT_MQTT Class)
Whether or not this message's Retain flag is set.
Object Oriented Interface
public function getOutgoingMessageRetained($outgoingmessageindex);
Procedural Interface
ipworksiot_mqtt_get($res, 38 , $outgoingmessageindex);
Default Value
false
Remarks
Whether or not this message's Retain flag is set.
The $outgoingmessageindex parameter specifies the index of the item in the array. The size of the array is controlled by the OutgoingMessageCount property.
This property is read-only and not available at design time.
Data Type
Boolean
OutgoingMessageState Property (IPWorksIoT_MQTT Class)
This message's current state.
Object Oriented Interface
public function getOutgoingMessageState($outgoingmessageindex);
Procedural Interface
ipworksiot_mqtt_get($res, 39 , $outgoingmessageindex);
Default Value
0
Remarks
This message's current state.
Possible Outgoing Message States:
Value | Description |
0 | PUBLISH sent, waiting for PUBACK (QoS 1 only) |
1 | PUBLISH sent, waiting for PUBREC (QoS 2 only) |
2 | PUBREC received, sending PUBREL (QoS 2 only) |
3 | PUBREL sent, waiting for PUBCOMP (QoS 2 only) |
4 | Final acknowledgment received |
Possible Incoming Message States:
Value | Description |
5 | PUBLISH received, sending PUBACK (QoS 1 only) |
6 | PUBLISH received, sending PUBREC (QoS 2 only) |
7 | PUBREC sent, waiting for PUBREL (QoS 2 only) |
8 | PUBREL received, sending PUBCOMP (QoS 2 only) |
9 | Final acknowledgment sent |
The $outgoingmessageindex parameter specifies the index of the item in the array. The size of the array is controlled by the OutgoingMessageCount property.
This property is read-only and not available at design time.
Data Type
Integer
OutgoingMessageSubscriptionIdentifiers Property (IPWorksIoT_MQTT Class)
A comma separated list of any SubscriptionIdentifiers associated with any client subscription(s) that caused this message to be delivered.
Object Oriented Interface
public function getOutgoingMessageSubscriptionIdentifiers($outgoingmessageindex);
Procedural Interface
ipworksiot_mqtt_get($res, 40 , $outgoingmessageindex);
Default Value
''
Remarks
A comma separated list of any SubscriptionIdentifiers associated with any client subscription(s) that caused this message to be delivered.
This property is only applicable to incoming messages.
If SubscriptionIdentifier is set when subscribing, it will be included in any messages delivered by the broker for the topics specified in that packet.
See the Subscribe method for more details.
Valid only for MQTT 5.
The $outgoingmessageindex parameter specifies the index of the item in the array. The size of the array is controlled by the OutgoingMessageCount property.
This property is read-only and not available at design time.
Data Type
String
OutgoingMessageTopic Property (IPWorksIoT_MQTT Class)
This message's topic.
Object Oriented Interface
public function getOutgoingMessageTopic($outgoingmessageindex);
Procedural Interface
ipworksiot_mqtt_get($res, 41 , $outgoingmessageindex);
Default Value
''
Remarks
This message's topic.
MQTT 5 Notes:
If this value is empty, the OutgoingMessageTopicAlias property holds the assigned alias for the topic.
If this value is not empty and OutgoingMessageTopicAlias is non-zero,
The $outgoingmessageindex parameter specifies the index of the item in the array. The size of the array is controlled by the OutgoingMessageCount property.
This property is read-only and not available at design time.
Data Type
String
OutgoingMessageTopicAlias Property (IPWorksIoT_MQTT Class)
An integer used to identify the topic instead of the full topic filter in order to reduce the size of the publish packet.
Object Oriented Interface
public function getOutgoingMessageTopicAlias($outgoingmessageindex);
Procedural Interface
ipworksiot_mqtt_get($res, 42 , $outgoingmessageindex);
Default Value
0
Remarks
An integer used to identify the topic instead of the full topic filter in order to reduce the size of the publish packet.
If a non-zero topic alias is received, the client should establish a new topic alias mapping or use an existing mapping, depending on whether the OutgoingMessageTopic string is empty.
For details on setting topic aliases for outgoing messages, see the TopicAlias configuration setting.
Valid only for MQTT 5.
The $outgoingmessageindex parameter specifies the index of the item in the array. The size of the array is controlled by the OutgoingMessageCount property.
This property is read-only and not available at design time.
Data Type
Integer
Password Property (IPWorksIoT_MQTT Class)
A password if authentication is to be used.
Object Oriented Interface
public function getPassword(); public function setPassword($value);
Procedural Interface
ipworksiot_mqtt_get($res, 43 ); ipworksiot_mqtt_set($res, 43, $value );
Default Value
''
Remarks
This property can be set to a password if authentication is to be used.
In MQTT 3.1.1, while a User may be specified without a Password, setting a Password without a User is not supported; attempting to do so will cause the server to reject the connection attempt.
In MQTT 5, a Password may be set without a User, allowing the field to be used for credentials other than a password.
This property is not available at design time.
Data Type
String
ReadyToSend Property (IPWorksIoT_MQTT Class)
Indicates whether the class is ready to send data.
Object Oriented Interface
public function getReadyToSend();
Procedural Interface
ipworksiot_mqtt_get($res, 44 );
Default Value
false
Remarks
This property indicates that the underlying TCP/IP subsystem is ready to accept data. This is True after connecting to the remote host, and will become False if a call to PublishData or PublishMessage fails due to a WOULDBLOCK condition.
Once data can be sent again, the ReadyToSend event will fire and this property will be True.
If a WOULDBLOCK error occurs while sending a message the class will automatically complete the transmission when sending is possible. No action needs to be taken to re-send the message. ReadyToSend will fire after the class completes any partially sent messages.
This property is read-only and not available at design time.
Data Type
Boolean
RemoteHost Property (IPWorksIoT_MQTT Class)
The address of the remote host. Domain names are resolved to IP addresses.
Object Oriented Interface
public function getRemoteHost(); public function setRemoteHost($value);
Procedural Interface
ipworksiot_mqtt_get($res, 45 ); ipworksiot_mqtt_set($res, 45, $value );
Default Value
''
Remarks
This property specifies the IP address (IP number in dotted internet format) or Domain Name of the remote host. It is set before a connection is attempted and cannot be changed once a connection is established.
If this property is set to a Domain Name, a DNS request is initiated, and upon successful termination of the request, this property is set to the corresponding address. If the search is not successful, an error is returned.
If the class is configured to use a SOCKS firewall, the value assigned to this property may be preceded with an "*". If this is the case, the host name is passed to the firewall unresolved and the firewall performs the DNS resolution.
By default the class will connect in plaintext. To enable SSL set SSLEnabled to True.
In addition, WebSocket connections are supported. To connect using WebSockets specify a hostname beginning with ws:// (plaintext) or wss:// (SSL). For instance, ws://test.mosquitto.org.
Data Type
String
RemotePort Property (IPWorksIoT_MQTT Class)
The port of the MQTT server (default is 1883). The default port for SSL is 8883.
Object Oriented Interface
public function getRemotePort(); public function setRemotePort($value);
Procedural Interface
ipworksiot_mqtt_get($res, 46 ); ipworksiot_mqtt_set($res, 46, $value );
Default Value
1883
Remarks
This property specifies a service port on the remote host to connect to.
A valid port number (a value between 1 and 65535) is required for the connection to take place. The property must be set before a connection is attempted and cannot be changed once a connection is established. Any attempt to change this property while connected will fail with an error.
This property is not available at design time.
Data Type
Integer
SSLAcceptServerCertEncoded Property (IPWorksIoT_MQTT Class)
This is the certificate (PEM/base64 encoded).
Object Oriented Interface
public function getSSLAcceptServerCertEncoded(); public function setSSLAcceptServerCertEncoded($value);
Procedural Interface
ipworksiot_mqtt_get($res, 48 ); ipworksiot_mqtt_set($res, 48, $value );
Default Value
''
Remarks
This is the certificate (PEM/Base64 encoded). This property is used to assign a specific certificate. The SSLAcceptServerCertStore and SSLAcceptServerCertSubject properties also may be used to specify a certificate.
When SSLAcceptServerCertEncoded is set, a search is initiated in the current SSLAcceptServerCertStore for the private key of the certificate. If the key is found, SSLAcceptServerCertSubject is updated to reflect the full subject of the selected certificate; otherwise, SSLAcceptServerCertSubject is set to an empty string.
This property is not available at design time.
Data Type
Binary String
SSLCertEncoded Property (IPWorksIoT_MQTT Class)
This is the certificate (PEM/base64 encoded).
Object Oriented Interface
public function getSSLCertEncoded(); public function setSSLCertEncoded($value);
Procedural Interface
ipworksiot_mqtt_get($res, 76 ); ipworksiot_mqtt_set($res, 76, $value );
Default Value
''
Remarks
This is the certificate (PEM/Base64 encoded). This property is used to assign a specific certificate. The SSLCertStore and SSLCertSubject properties also may be used to specify a certificate.
When SSLCertEncoded is set, a search is initiated in the current SSLCertStore for the private key of the certificate. If the key is found, SSLCertSubject is updated to reflect the full subject of the selected certificate; otherwise, SSLCertSubject is set to an empty string.
This property is not available at design time.
Data Type
Binary String
SSLCertStore Property (IPWorksIoT_MQTT Class)
This is the name of the certificate store for the client certificate.
Object Oriented Interface
public function getSSLCertStore(); public function setSSLCertStore($value);
Procedural Interface
ipworksiot_mqtt_get($res, 92 ); ipworksiot_mqtt_set($res, 92, $value );
Default Value
'MY'
Remarks
This is the name of the certificate store for the client certificate.
The SSLCertStoreType property denotes the type of the certificate store specified by SSLCertStore. If the store is password protected, specify the password in SSLCertStorePassword.
SSLCertStore is used in conjunction with the SSLCertSubject property to specify client certificates. If SSLCertStore has a value, and SSLCertSubject or SSLCertEncoded is set, a search for a certificate is initiated. Please see the SSLCertSubject property for details.
Designations of certificate stores are platform dependent.
The following designations are the most common User and Machine certificate stores in Windows:
MY | A certificate store holding personal certificates with their associated private keys. |
CA | Certifying authority certificates. |
ROOT | Root certificates. |
When the certificate store type is PFXFile, this property must be set to the name of the file. When the type is PFXBlob, the property must be set to the binary contents of a PFX file (i.e., PKCS#12 certificate store).
Data Type
Binary String
SSLCertStorePassword Property (IPWorksIoT_MQTT Class)
If the type of certificate store requires a password, this property is used to specify the password needed to open the certificate store.
Object Oriented Interface
public function getSSLCertStorePassword(); public function setSSLCertStorePassword($value);
Procedural Interface
ipworksiot_mqtt_get($res, 93 ); ipworksiot_mqtt_set($res, 93, $value );
Default Value
''
Remarks
If the type of certificate store requires a password, this property is used to specify the password needed to open the certificate store.
Data Type
String
SSLCertStoreType Property (IPWorksIoT_MQTT Class)
This is the type of certificate store for this certificate.
Object Oriented Interface
public function getSSLCertStoreType(); public function setSSLCertStoreType($value);
Procedural Interface
ipworksiot_mqtt_get($res, 94 ); ipworksiot_mqtt_set($res, 94, $value );
Default Value
0
Remarks
This is the type of certificate store for this certificate.
The class supports both public and private keys in a variety of formats. When the cstAuto value is used, the class will automatically determine the type. This property can take one of the following values:
0 (cstUser - default) | For Windows, this specifies that the certificate store is a certificate store owned by the current user.
Note: This store type is not available in Java. |
1 (cstMachine) | For Windows, this specifies that the certificate store is a machine store.
Note: This store type is not available in Java. |
2 (cstPFXFile) | The certificate store is the name of a PFX (PKCS#12) file containing certificates. |
3 (cstPFXBlob) | The certificate store is a string (binary or Base64-encoded) representing a certificate store in PFX (PKCS#12) format. |
4 (cstJKSFile) | The certificate store is the name of a Java Key Store (JKS) file containing certificates.
Note: This store type is only available in Java. |
5 (cstJKSBlob) | The certificate store is a string (binary or Base64-encoded) representing a certificate store in Java Key Store (JKS) format.
Note: this store type is only available in Java. |
6 (cstPEMKeyFile) | The certificate store is the name of a PEM-encoded file that contains a private key and an optional certificate. |
7 (cstPEMKeyBlob) | The certificate store is a string (binary or Base64-encoded) that contains a private key and an optional certificate. |
8 (cstPublicKeyFile) | The certificate store is the name of a file that contains a PEM- or DER-encoded public key certificate. |
9 (cstPublicKeyBlob) | The certificate store is a string (binary or Base64-encoded) that contains a PEM- or DER-encoded public key certificate. |
10 (cstSSHPublicKeyBlob) | The certificate store is a string (binary or Base64-encoded) that contains an SSH-style public key. |
11 (cstP7BFile) | The certificate store is the name of a PKCS#7 file containing certificates. |
12 (cstP7BBlob) | The certificate store is a string (binary) representing a certificate store in PKCS#7 format. |
13 (cstSSHPublicKeyFile) | The certificate store is the name of a file that contains an SSH-style public key. |
14 (cstPPKFile) | The certificate store is the name of a file that contains a PPK (PuTTY Private Key). |
15 (cstPPKBlob) | The certificate store is a string (binary) that contains a PPK (PuTTY Private Key). |
16 (cstXMLFile) | The certificate store is the name of a file that contains a certificate in XML format. |
17 (cstXMLBlob) | The certificate store is a string that contains a certificate in XML format. |
18 (cstJWKFile) | The certificate store is the name of a file that contains a JWK (JSON Web Key). |
19 (cstJWKBlob) | The certificate store is a string that contains a JWK (JSON Web Key). |
21 (cstBCFKSFile) | The certificate store is the name of a file that contains a BCFKS (Bouncy Castle FIPS Key Store).
Note: This store type is only available in Java and .NET. |
22 (cstBCFKSBlob) | The certificate store is a string (binary or Base64-encoded) representing a certificate store in BCFKS (Bouncy Castle FIPS Key Store) format.
Note: This store type is only available in Java and .NET. |
23 (cstPKCS11) | The certificate is present on a physical security key accessible via a PKCS#11 interface.
To use a security key, the necessary data must first be collected using the CertMgr class. The ListStoreCertificates method may be called after setting CertStoreType to cstPKCS11, CertStorePassword to the PIN, and CertStore to the full path of the PKCS#11 DLL. The certificate information returned in the CertList event's CertEncoded parameter may be saved for later use. When using a certificate, pass the previously saved security key information as the SSLCertStore and set SSLCertStorePassword to the PIN. Code Example. SSH Authentication with Security Key:
|
99 (cstAuto) | The store type is automatically detected from the input data. This setting may be used with both public and private keys and can detect any of the supported formats automatically. |
Data Type
Integer
SSLCertSubject Property (IPWorksIoT_MQTT Class)
This is the subject of the certificate used for client authentication.
Object Oriented Interface
public function getSSLCertSubject(); public function setSSLCertSubject($value);
Procedural Interface
ipworksiot_mqtt_get($res, 95 ); ipworksiot_mqtt_set($res, 95, $value );
Default Value
''
Remarks
This is the subject of the certificate used for client authentication.
This property must be set after all other certificate properties are set. When this property is set, a search is performed in the current certificate store to locate a certificate with a matching subject.
If a matching certificate is found, the property is set to the full subject of the matching certificate.
If an exact match is not found, the store is searched for subjects containing the value of the property.
If a match is still not found, the property is set to an empty string, and no certificate is selected.
The special value "*" picks a random certificate in the certificate store.
The certificate subject is a comma-separated list of distinguished name fields and values. For instance, "CN=www.server.com, OU=test, C=US, E=support@nsoftware.com". Common fields and their meanings are as follows:
Field | Meaning |
CN | Common Name. This is commonly a hostname like www.server.com. |
O | Organization |
OU | Organizational Unit |
L | Locality |
S | State |
C | Country |
E | Email Address |
If a field value contains a comma, it must be quoted.
Data Type
String
SSLEnabled Property (IPWorksIoT_MQTT Class)
Whether TLS/SSL is enabled.
Object Oriented Interface
public function getSSLEnabled(); public function setSSLEnabled($value);
Procedural Interface
ipworksiot_mqtt_get($res, 103 ); ipworksiot_mqtt_set($res, 103, $value );
Default Value
false
Remarks
This setting specifies whether TLS/SSL is enabled in the class. When False (default) the class operates in plaintext mode. When True TLS/SSL is enabled.
TLS/SSL may also be enabled by setting SSLStartMode. Setting SSLStartMode will automatically update this property value.
This property is not available at design time.
Data Type
Boolean
SSLProvider Property (IPWorksIoT_MQTT Class)
This specifies the SSL/TLS implementation to use.
Object Oriented Interface
public function getSSLProvider(); public function setSSLProvider($value);
Procedural Interface
ipworksiot_mqtt_get($res, 104 ); ipworksiot_mqtt_set($res, 104, $value );
Default Value
0
Remarks
This property specifies the SSL/TLS implementation to use. In most cases the default value of 0 (Automatic) is recommended and should not be changed. When set to 0 (Automatic) the class will select whether to use the platform implementation or the internal implementation depending on the operating system as well as the TLS version being used.
Possible values are:
0 (sslpAutomatic - default) | Automatically selects the appropriate implementation. |
1 (sslpPlatform) | Uses the platform/system implementation. |
2 (sslpInternal) | Uses the internal implementation. |
In most cases using the default value (Automatic) is recommended. The class will select a provider depending on the current platform.
When Automatic is selected, on Windows the class will use the platform implementation. On Linux/macOS the class will use the internal implementation. When TLS 1.3 is enabled via SSLEnabledProtocols the internal implementation is used on all platforms.
Data Type
Integer
SSLServerCertEncoded Property (IPWorksIoT_MQTT Class)
This is the certificate (PEM/base64 encoded).
Object Oriented Interface
public function getSSLServerCertEncoded();
Procedural Interface
ipworksiot_mqtt_get($res, 106 );
Default Value
''
Remarks
This is the certificate (PEM/Base64 encoded). This property is used to assign a specific certificate. The SSLServerCertStore and SSLServerCertSubject properties also may be used to specify a certificate.
When SSLServerCertEncoded is set, a search is initiated in the current SSLServerCertStore for the private key of the certificate. If the key is found, SSLServerCertSubject is updated to reflect the full subject of the selected certificate; otherwise, SSLServerCertSubject is set to an empty string.
This property is read-only and not available at design time.
Data Type
Binary String
Timeout Property (IPWorksIoT_MQTT Class)
A timeout for the class.
Object Oriented Interface
public function getTimeout(); public function setTimeout($value);
Procedural Interface
ipworksiot_mqtt_get($res, 133 ); ipworksiot_mqtt_set($res, 133, $value );
Default Value
60
Remarks
If the Timeout property is set to 0, all operations return immediately, potentially failing with a WOULDBLOCK error if data cannot be sent immediately.
If Timeout is set to a positive value, data is sent in a blocking manner and the class will wait for the operation to complete before returning control. The class will handle any potential WOULDBLOCK errors internally and automatically retry the operation for a maximum of Timeout seconds.
The class will use DoEvents to enter an efficient wait loop during any potential waiting period, making sure that all system events are processed immediately as they arrive. This ensures that the host application does not "freeze" and remains responsive.
If Timeout expires, and the operation is not yet complete, the class fails with an error.
Please note that by default, all timeouts are inactivity timeouts, i.e. the timeout period is extended by Timeout seconds when any amount of data is successfully sent or received.
The default value for the Timeout property is 60 seconds.
Data Type
Integer
User Property (IPWorksIoT_MQTT Class)
A username if authentication is to be used.
Object Oriented Interface
public function getUser(); public function setUser($value);
Procedural Interface
ipworksiot_mqtt_get($res, 134 ); ipworksiot_mqtt_set($res, 134, $value );
Default Value
''
Remarks
This property can be set to a username if authentication is to be used.
In MQTT 3.1.1, while a User may be specified without a Password, setting a Password without a User is not supported; attempting to do so will cause the server to reject the connection attempt.
In MQTT 5, a Password may be set without a User, allowing the field to be used for credentials other than a password.
This property is not available at design time.
Data Type
String
Version Property (IPWorksIoT_MQTT Class)
The MQTT protocol version that the class will conform to.
Object Oriented Interface
public function getVersion(); public function setVersion($value);
Procedural Interface
ipworksiot_mqtt_get($res, 135 ); ipworksiot_mqtt_set($res, 135, $value );
Default Value
0
Remarks
This property specifies the version of the MQTT protocol to use. Possible values are:
0 (mvV3 - default) | MQTT 3.1.1 |
1 (mvV5) | MQTT 5 |
This property is not available at design time.
Data Type
Integer
WillMessage Property (IPWorksIoT_MQTT Class)
The message that the server should publish in the event of an ungraceful disconnection.
Object Oriented Interface
public function getWillMessage(); public function setWillMessage($value);
Procedural Interface
ipworksiot_mqtt_get($res, 136 ); ipworksiot_mqtt_set($res, 136, $value );
Default Value
''
Remarks
This property may be set before calling Connect to specify to the server a message that should be published on WillTopic if the connection is closed ungracefully. Since it is sent to the server when Connect is called, this property's value cannot be changed when already connected.
Note that the WillMessage will only be sent to the server when Connect is called if WillTopic is set.
Refer to WillTopic for more information about MQTT Will functionality.
This property is not available at design time.
Data Type
String
WillTopic Property (IPWorksIoT_MQTT Class)
The topic that the server should publish the WillMessage to in the event of an ungraceful disconnection.
Object Oriented Interface
public function getWillTopic(); public function setWillTopic($value);
Procedural Interface
ipworksiot_mqtt_get($res, 137 ); ipworksiot_mqtt_set($res, 137, $value );
Default Value
''
Remarks
This property may be set before calling Connect to specify the topic name that the server should publish the WillMessage on if the connection is closed ungracefully. Since it is sent to the server when Connect is called, this property's value cannot be changed when already connected.
MQTT Wills
The Will feature of MQTT allows a client to specify to the server a WillMessage to publish (as well as a WillTopic to publish it on) in the event of an ungraceful disconnection.
An "ungraceful disconnection" is any disconnection other than one triggered by calling Disconnect (in which case the server discards the Will message without publishing it). Note that in MQTT 5, the client can set a DisconnectReasonCode of 0x04 before calling Disconnect to instruct the server to publish the Will message anyway.
In addition to the WillTopic and WillMessage properties, the WillQOS setting may be used to specify the Will message's QoS level, and the WillRetain setting to set the Will message's Retain flag. Refer to those settings for more information.
If WillTopic is set to empty string (default) when Connect is called, the class will not send a Will to the server.
In MQTT 5, the "WillDelayInterval" value in the WillProperties config can specify a delay between the ending of the connection and sending the will message, so that the WillMessage will not be sent if a connection is re-established within a certain period of time.
This property is not available at design time.
Data Type
String
Config Method (IPWorksIoT_MQTT Class)
Sets or retrieves a configuration setting.
Object Oriented Interface
public function doConfig($configurationstring);
Procedural Interface
ipworksiot_mqtt_do_config($res, $configurationstring);
Remarks
Config is a generic method available in every class. It is used to set and retrieve configuration settings for the class.
These settings are similar in functionality to properties, but they are rarely used. In order to avoid "polluting" the property namespace of the class, access to these internal properties is provided through the Config method.
To set a configuration setting named PROPERTY, you must call Config("PROPERTY=VALUE"), where VALUE is the value of the setting expressed as a string. For boolean values, use the strings "True", "False", "0", "1", "Yes", or "No" (case does not matter).
To read (query) the value of a configuration setting, you must call Config("PROPERTY"). The value will be returned as a string.
Connect Method (IPWorksIoT_MQTT Class)
Connects to the remote host.
Object Oriented Interface
public function doConnect();
Procedural Interface
ipworksiot_mqtt_do_connect($res);
Remarks
This method connects to the remote host specified by RemoteHost and RemotePort. Calling this method is equivalent to setting the Connected property to True.
By default the class will connect in plaintext. To enable SSL set SSLEnabled to True.
In addition, WebSocket connections are supported. To connect using WebSockets specify a hostname beginning with ws:// (plaintext) or wss:// (SSL). For instance, ws://test.mosquitto.org.
When connecting to an MQTT server, the class sends the following information:
- The values of the ClientId, CleanSession, and KeepAliveInterval properties.
- The value of the User property (if non-empty).
- The value of the Password property (if non-empty).
- The values of the WillTopic and WillMessage properties and the WillQOS and WillRetain configuration settings.
- MQTT 5 specific values from ClientTopicAliasMax, SessionExpInterval, ConnectProperties and WillProperties.
If CleanSession is True, check the SessionPresent configuration setting once connected to determine whether the server actually had any session state saved.
Refer to CleanSession, SaveSession, and RestoreSession for more information about MQTT sessions and session state persistence; refer to WillTopic, WillMessage, WillQOS, and WillRetain for more information about MQTT Wills.
Basic Connection Example
mqtt1.ClientId = "testClient";
mqtt1.CleanSession = true;
mqtt1.KeepAliveInterval = 30;
mqtt1.WillTopic = "wills/" + mqtt1.ClientId;
mqtt1.WillMessage = mqtt1.ClientId + " was disconnected ungracefully!";
mqtt1.RemoteHost = "mqtt.test-server.com";
mqtt1.RemotePort = 1883;
mqtt1.Connect();
ConnectTo Method (IPWorksIoT_MQTT Class)
Connects to the remote host.
Object Oriented Interface
public function doConnectTo($host, $port);
Procedural Interface
ipworksiot_mqtt_do_connectto($res, $host, $port);
Remarks
This method connects to the remote host specified by the Host and Port parameters. Calling this method is equivalent to setting the RemoteHost property to Host, setting RemotePort to Port, and then setting the Connected property to True.
By default the class will connect in plaintext. To enable SSL set SSLEnabled to True.
In addition, WebSocket connections are supported. To connect using WebSockets specify a hostname beginning with ws:// (plaintext) or wss:// (SSL). For instance, ws://test.mosquitto.org.
When connecting to an MQTT server, the class sends the following information:
- The values of the ClientId, CleanSession, and KeepAliveInterval properties.
- The value of the User property (if non-empty).
- The value of the Password property (if non-empty).
- The values of the WillTopic and WillMessage properties and the WillQOS and WillRetain configuration settings.
- MQTT 5 specific values from ClientTopicAliasMax, SessionExpInterval, ConnectProperties and WillProperties.
If CleanSession is True, check the SessionPresent configuration setting once connected to determine whether the server actually had any session state saved.
Refer to CleanSession, SaveSession, and RestoreSession for more information about MQTT sessions and session state persistence; refer to WillTopic, WillMessage, WillQOS, and WillRetain for more information about MQTT Wills.
Basic Connection Example
mqtt1.ClientId = "testClient";
mqtt1.CleanSession = true;
mqtt1.KeepAliveInterval = 30;
mqtt1.WillTopic = "wills/" + mqtt1.ClientId;
mqtt1.WillMessage = mqtt1.ClientId + " was disconnected ungracefully!";
mqtt1.ConnectTo("mqtt.test-server.com", 1883);
Disconnect Method (IPWorksIoT_MQTT Class)
This method disconnects from the remote host.
Object Oriented Interface
public function doDisconnect();
Procedural Interface
ipworksiot_mqtt_do_disconnect($res);
Remarks
This method disconnects from the remote host. Calling this method is equivalent to setting the Connected property to False.
Refer to the Connected property for more information about MQTT-specific behavior.
DoEvents Method (IPWorksIoT_MQTT Class)
Processes events from the internal message queue.
Object Oriented Interface
public function doEvents();
Procedural Interface
ipworksiot_mqtt_do_doevents($res);
Remarks
When DoEvents is called, the class processes any available events. If no events are available, it waits for a preset period of time, and then returns.
Interrupt Method (IPWorksIoT_MQTT Class)
Interrupt the current action and disconnects from the remote host.
Object Oriented Interface
public function doInterrupt();
Procedural Interface
ipworksiot_mqtt_do_interrupt($res);
Remarks
This method will interrupt the current method (if applicable) and cause the class to disconnect from the remote host.
PublishData Method (IPWorksIoT_MQTT Class)
Publishes a message with a raw data payload.
Object Oriented Interface
public function doPublishData($topic, $qos, $data);
Procedural Interface
ipworksiot_mqtt_do_publishdata($res, $topic, $qos, $data);
Remarks
This method publishes an MQTT message with a raw data payload to the specified Topic at a given QOS level.
Publish Examples
// Publish a simple string-based message.
mqtt1.PublishMessage("/home/floor1/security/camera2", 1, "Cat detected!");
// Publish a raw data message.
byte[] catPicture = ...;
mqtt1.PublishData("/home/floor1/security/camera2", 1, catPicture);
The Retain configuration setting may be set before calling this method in order to publish a retained message (see Retain for more information).
Topic Names
Topic names are case-sensitive, must be 1-65535 characters long, and may include any characters except wildcard characters (# and +) and the null character. The / character separates levels within a topic name, which is important in the context of subscribing (see Subscribe for more information).
Keep in mind that using topic names with leading or trailing / characters will cause topic levels with zero-length names to be created. That is, a topic name like /a/b/ consists of the levels '', 'a', 'b', and ''. Depending on the server, multiple successive /s may also cause zero-length levels to be created, or may be treated as a single /.
Topic names that begin with a $ are "system topics", and servers will typically prevent clients from publishing to them.
For example, topic names that begin with $share are reserved for Shared Subscriptions (see Subscribe).
QoS Values
QoS values set the service level for delivery of a message. Values range from 0 to 2 and have the following meanings:
QoS Level | Description |
0 | At most once - The published message is sent once, and if it does not arrive it is lost. |
1 | At least once - Guarantees that the published message arrives, but there may be duplicates. |
2 | Exactly once - Guarantees that the publish message arrives and that there are no duplicates. |
QoS is not guaranteed to be end-to-end in MQTT. The server must downgrade a message's QoS level when delivering it to clients who specified a lower "maximum acceptable" QoS when they subscribed. For example, if Client X subscribes to a topic at QoS 1, and Client Y publishes a message to that topic at QoS 2, the server will downgrade the message to QoS 1 when attempting to deliver it to Client X.
Outbound Message Processing
Outgoing messages with a QoS of 1 follow these steps:
- The class sends the PUBLISH packet, then adds the message to OutgoingMessage*.
- The class waits to receive a PUBACK (publish acknowledgment) packet.
- The MessageAck event is fired.
- The message is removed from OutgoingMessage*.
- The MessageOut event is fired.
Outgoing messages with a QoS of 2 follow these steps:
- The class sends the PUBLISH packet, then adds the message to OutgoingMessage*.
- The class waits to receive a PUBREC (publish received) packet.
- The class sends a PUBREL (publish release) packet in response.
- The class waits to receive a PUBCOMP (publish complete) packet.
- The MessageAck event is fired.
- The message is removed from OutgoingMessage*.
- The MessageOut event is fired.
In MQTT 3.1.1, the RepublishInterval configuration setting, if set to a non-zero value (default), controls how long the class will wait to receive a PUBACK (for QoS 1) or PUBREC (for QoS 2) before automatically republishing an outgoing message. In MQTT 5, messages are only republished if the client is disconnected before receiving a PUBACK or PUBREC.
MQTT 5 Notes
MQTT 5 makes a number of new features available when publishing messages, including:
- TopicAlias - Set an integer alias along with the topic name when first publishing a message. When publishing additional messages to the same topic if TopicAlias is set the Topic parameter does not need to be set. This reduces the size of the message sent to the server.
- Request / Response - Set a ResponseTopic which identifies the topic to which a receiver should respond.
Some of these features require configuration settings to be set prior to publishing. In these cases, note that these configuration settings will continue to be applicable to any future PUBLISH packets sent with the method unless they are updated or reset. To prevent clear a previously set configuration setting, set it to "", or -1 (for integers).
See the OutgoingMessageProperties configuration setting for additional details.
PublishMessage Method (IPWorksIoT_MQTT Class)
Publishes a message with a string payload.
Object Oriented Interface
public function doPublishMessage($topic, $qos, $message);
Procedural Interface
ipworksiot_mqtt_do_publishmessage($res, $topic, $qos, $message);
Remarks
This method publishes an MQTT message with a string payload to the specified Topic at a given QOS level.
Publish Examples
// Publish a simple string-based message.
mqtt1.PublishMessage("/home/floor1/security/camera2", 1, "Cat detected!");
// Publish a raw data message.
byte[] catPicture = ...;
mqtt1.PublishData("/home/floor1/security/camera2", 1, catPicture);
The Retain configuration setting may be set before calling this method in order to publish a retained message (see Retain for more information).
Topic Names
Topic names are case-sensitive, must be 1-65535 characters long, and may include any characters except wildcard characters (# and +) and the null character. The / character separates levels within a topic name, which is important in the context of subscribing (see Subscribe for more information).
Keep in mind that using topic names with leading or trailing / characters will cause topic levels with zero-length names to be created. That is, a topic name like /a/b/ consists of the levels '', 'a', 'b', and ''. Depending on the server, multiple successive /s may also cause zero-length levels to be created, or may be treated as a single /.
Topic names that begin with a $ are "system topics", and servers will typically prevent clients from publishing to them.
For example, topic names that begin with $share are reserved for Shared Subscriptions (see Subscribe).
QoS Values
QoS values set the service level for delivery of a message. Values range from 0 to 2 and have the following meanings:
QoS Level | Description |
0 | At most once - The published message is sent once, and if it does not arrive it is lost. |
1 | At least once - Guarantees that the published message arrives, but there may be duplicates. |
2 | Exactly once - Guarantees that the publish message arrives and that there are no duplicates. |
QoS is not guaranteed to be end-to-end in MQTT. The server must downgrade a message's QoS level when delivering it to clients who specified a lower "maximum acceptable" QoS when they subscribed. For example, if Client X subscribes to a topic at QoS 1, and Client Y publishes a message to that topic at QoS 2, the server will downgrade the message to QoS 1 when attempting to deliver it to Client X.
Outbound Message Processing
Outgoing messages with a QoS of 1 follow these steps:
- The class sends the PUBLISH packet, then adds the message to OutgoingMessage*.
- The class waits to receive a PUBACK (publish acknowledgment) packet.
- The MessageAck event is fired.
- The message is removed from OutgoingMessage*.
- The MessageOut event is fired.
Outgoing messages with a QoS of 2 follow these steps:
- The class sends the PUBLISH packet, then adds the message to OutgoingMessage*.
- The class waits to receive a PUBREC (publish received) packet.
- The class sends a PUBREL (publish release) packet in response.
- The class waits to receive a PUBCOMP (publish complete) packet.
- The MessageAck event is fired.
- The message is removed from OutgoingMessage*.
- The MessageOut event is fired.
In MQTT 3.1.1, the RepublishInterval configuration setting, if set to a non-zero value (default), controls how long the class will wait to receive a PUBACK (for QoS 1) or PUBREC (for QoS 2) before automatically republishing an outgoing message. In MQTT 5, messages are only republished if the client is disconnected before receiving a PUBACK or PUBREC.
MQTT 5 Notes
MQTT 5 makes a number of new features available when publishing messages, including:
- TopicAlias - Set an integer alias along with the topic name when first publishing a message. When publishing additional messages to the same topic if TopicAlias is set the Topic parameter does not need to be set. This reduces the size of the message sent to the server.
- Request / Response - Set a ResponseTopic which identifies the topic to which a receiver should respond.
Some of these features require configuration settings to be set prior to publishing. In these cases, note that these configuration settings will continue to be applicable to any future PUBLISH packets sent with the method unless they are updated or reset. To prevent clear a previously set configuration setting, set it to "", or -1 (for integers).
See the OutgoingMessageProperties configuration setting for additional details.
Reset Method (IPWorksIoT_MQTT Class)
Reset the class.
Object Oriented Interface
public function doReset();
Procedural Interface
ipworksiot_mqtt_do_reset($res);
Remarks
This method will reset the class's properties to their default values.
RestoreSession Method (IPWorksIoT_MQTT Class)
Restores session state data.
Object Oriented Interface
public function doRestoreSession($statedata);
Procedural Interface
ipworksiot_mqtt_do_restoresession($res, $statedata);
Remarks
This method restores previously-saved session state data and sets CleanSession to False. If the SessionStateFile configuration setting is set, the class will use the contents of that file to restore the session state data, ignoring the string passed to this method.
Depending on the elapsed time between connections the server may discard any previously saved session data on its side.
In MQTT 3.1.1, the time after which the server discards saved session data is not defined in the protocol specification and may vary between implementations. As a result, when re-connecting it may not be known if the server is capable of restoring a previous session.
To determine if a session can be restored on connection, set CleanSession to False, ClientId to the same value used in the initial connection, and call ConnectTo.
When the Connected event fires, query the SessionPresent configuration setting. If SessionPresent is True the session should be restored by calling RestoreSession. If SessionPresent is False the session should not be restored so that the connection proceeds as a clean session.
Note: Not all servers support the use of SessionPresent.
Restore Session Example (Query SessionPresent)
mqtt1.CleanSession = false;
mqtt1.ClientId = clientId;
mqtt1.OnConnected += (s, e) => {
if (mqtt1.Config("SessionPresent").ToLower() == "true")
mqtt1.RestoreSession(sessionStr);
};
mqtt1.ConnectTo(host,port);
If it is known that the server has not discarded the session state, for instance from familiarity with the server implementation and its behavior, then a simplified procedure can be performed. Simply set ClientId to the value used in the initial connection, call RestoreSession, and then call ConnectTo.
Restore Session Example (Server Status Known)
mqtt1.ClientId = clientId;
mqtt1.RestoreSession(sessionStr);
mqtt1.ConnectTo(host,port);
Refer to CleanSession and SaveSession for more information.
MQTT 5 Notes
In MQTT 5, the time after which the server discards saved session data is controlled by the SessionExpInterval. The server is required to store state data for the amount of time specified by this value, at which point it is required to delete it.
This feature allows the client to use its own time-based logic to determine whether it is necessary to call RestoreSession.
SaveSession Method (IPWorksIoT_MQTT Class)
Saves session state data.
Object Oriented Interface
public function doSaveSession();
Procedural Interface
ipworksiot_mqtt_do_savesession($res);
Remarks
This method saves session state data currently held by the class, returning it as a string that can later be used to restore it. If the SessionStateFile configuration setting is set, the class will also write the session state data to that file (creating and/or overwriting it, as necessary).
Refer to CleanSession and RestoreSession for more information.
Subscribe Method (IPWorksIoT_MQTT Class)
Subscribes the class to one or more topic filters.
Object Oriented Interface
public function doSubscribe($topicfilter, $qos);
Procedural Interface
ipworksiot_mqtt_do_subscribe($res, $topicfilter, $qos);
Remarks
This method subscribes the class to one or more topic filters using one or more QoS levels.
The Subscribed event will fire once for each topic filter given once the server acknowledges the subscription request(s). Keep in mind that the server is allowed to start publishing messages before it sends the acknowledgment.
It is legal to call Subscribe again for the same topic filter at any time, and pass a different QoS value at that time if desired. The Subscribed event will fire as normal when doing this.
Subscribe Examples
// Subscribed event handler.
mqtt1.OnSubscribed += (s, e) => {
if (e.ResponseCode <= 2)
Console.WriteLine("Subscribed to " + e.TopicFilter + " at QoS " + e.QOS + ".");
else
Console.WriteLine("Failed to subscribe to " + e.TopicFilter + ".");
};
// Basic, subscribe to some topic filters, all at the same QoS level.
mqtt1.Subscribe("home,home/floor1/+/temperature,home/floor2/#", 2);
// A bit more advanced, subscribe to the same topic filters, but at different QoS levels.
mqtt1.Config("TopicQOSArray=1,2,2");
// The 0 is ignored here since we've specified individual QoS values explicitly.
mqtt1.Subscribe("home,home/floor1/+/temperature,home/floor2/#", 0);
Topic Filters
The string passed for TopicFilter must contain one or more valid topic filter strings, separated by the delimiter string specified by the TopicDelimiter configuration setting (, by default).
A topic filter is a case-sensitive string between 1 and 65535 characters long (per topic filter), and can include any character other than the null character. Certain characters have special meanings:
- / - The topic level separator
- # - The multi-level wildcard (zero or more levels)
- + - The single-level wildcard (exactly one level)
- Leading $ - Denotes a "system topic"
Note that both types of wildcards may be used in the same topic filter.
Topic Level Separators
The topic level separator, as its name implies, is used to separate a topic name (or in this case, filter) into "levels". This concept of topic names having levels is what allows topic filters to match multiple topics through the use of wildcards. For the examples in the next sections, assume the following topics exist:
- home/floor1
- home/floor1/livingRoom
- home/floor1/livingRoom/temperature
- home/floor1/kitchen/temperature
- home/floor1/kitchen/fridge/temperature
- home/floor2/bedroom1
- home/floor2/bedroom1/temperature
Multi-level Wildcards
The multi-level wildcard character is used at the end of a topic filter to make it match an arbitrary number of successive levels. For example, the topic filter home/floor1/# would match the following topics:
- home/floor1 (because it can match zero levels)
- home/floor1/livingRoom
- home/floor1/livingRoom/temperature
- home/floor1/kitchen/temperature
- home/floor1/kitchen/fridge/temperature
Here are some things to keep in mind when using a multi-level wildcard:
- # must always be the last character in the topic filter (e.g., home/floor1/#/livingRoom is not valid)
- # must always be preceded by a / (e.g., home/floor1# is not valid)
- # by itself is a valid topic filter, and will match all topics except system topics
Single-level Wildcards
The single-level wildcard character is used between two /s in a topic filter to make it any single level. For example, the topic filter home/floor1/+/temperature would match the following topics:
- home/floor1/livingRoom/temperature
- home/floor1/kitchen/temperature
Any number of single-level wildcards are supported in a topic filter. For example, the topic filter home/+/+/temperature would match the following topics:
- home/floor1/livingRoom/temperature
- home/floor1/kitchen/temperature
- home/floor2/bedroom1/temperature
Here are some things to keep in mind when using single-level wildcards:
- + must always be separated from other levels using /s (e.g., home/floor1+ is invalid, but +/floor1/+ is valid)
- + by itself is a valid topic filter, and will match all topics with exactly one level in their name except system topics
- Remember, topic names with a leading / have a zero-length string as their first level. So a topic named /people would be matched by the topic filter +/+, but not by +
- + must match exactly one level. So for example, the topic filter home/floor1/kitchen/+/temperature would match /home/floor1/kitchen/fridge/temperature, but not home/floor1/kitchen/temperature
System Topics
Topic names which begin with a $ are "system topics". Typically, the server prohibits clients from publishing to such topics, but permits subscribing to them. As described above, wildcards will never match the first level of a topic if it begins with a $.
Note that MQTT 5 defines shared subscriptions, a special type of system topic. See the MQTT 5 notes below for more.
Requested QoS Values
The QoS value passed for QOS will be used to subscribe to all given topic filters, unless the TopicQOSArray configuration setting is used to specify explicit QoS values for each individual topic filter.
QoS values range from 0 to 2 and have the following meanings:
QoS Level | Description |
0 | At most once - The published message is sent once, and if it does not arrive it is lost. |
1 | At least once - Guarantees that the published message arrives, but there may be duplicates. |
2 | Exactly once - Guarantees that the publish message arrives and that there are no duplicates. |
QoS is not guaranteed to be end-to-end in MQTT. The server must downgrade a message's QoS level when delivering it to clients who specified a lower "maximum acceptable" QoS when they subscribed. For example, if Client X subscribes to a topic at QoS 1, and Client Y publishes a message to that topic at QoS 2, the server will downgrade the message to QoS 1 when attempting to deliver it to Client X.
MQTT 5 Notes
MQTT 5 defines several new features that apply to subscriptions, including Shared Subscriptions, Subscription Options and Subscription Identifiers. Some of these features require configuration settings to be set prior to calling Subscribe. In these cases, note that thee configuration settings will continue to be applied to any future SUBSCRIBE packets sent with the method unless they are updated or reset. To prevent a value from being included in packets after it has been set previously, set it to "", or -1 (for integers).
Shared Subscriptions
Shared subscriptions allow a client to subscribe to a topic as a part of a group of clients, where each client in the group is subscribing to the same topic. Each message published to such a group will be delivered to only one client in the group, making shared subscriptions useful when several clients share the processing of the publications in parallel.
Subscribing to a topic as part of a shared subscription is similar to a normal subscription, the only difference being the syntax of the topic filter passed to the Subscribe method.
The format of this filter is $share/{ShareName}/{filter}, where
- $share is a string literal identifying the subscription as a shared subscriptions.
- {ShareName} is a string at least one character long that must not include /, + or #.
- {filter} is a full topic filter formatted just as in a non-shared subscription.
Unsubscribing is done by passing the same value to the Unsubscribe method.
A shared subscription behaves the same way as a non-shared subscription, except that the $share/{ShareName} portion of the topic filter is ignored when filtering publication topics, and that the server will distribute delivery of messages amongst the group, with each message delivered to only one client per group per topic.
Shared subscriptions can be implemented without any additional properties or methods, simply by using the Subscribe and Unsubscribe methods. However, if it is necessary to verify that the feature is supported by the server, check the "SharedSubscriptionAvailable" value of the ConnAckProperties config.
Shared Subscription Example
mqtt1.Subscribe("$share/myShareGroup/myTopicFilter/subTopic", 2);
Subscription Options
MQTT 5 defines three subscription options which can be configured on a per-subscription basis and are useful for message bridge applications:
- No Local flag - indicates that messages must not be forwarded to a connection with a ClientId equal to the ClientId of the publishing connection (cannot be set on a shared subscription).
- Retain As Published flag - indicates that messages forwarded using this subscription keep the retain flag they were published with (as opposed to always being set to False).
- Retain Handling option - specifies whether retained messages are sent when the subscription is established. Possible values are:
0 Send retained messages at the time of the subscribe 1 Send retained messages at subscribe only if the subscription does not currently exist 2 Do not send retained messages at the time of the subscribe
To specify these options in the subscribe method, the class has three corresponding configuration settings (TopicNLArray, TopicRAPArray and TopicRHArray) which each take a string value in the form of a comma-separated list. Each element in the list corresponds to a topic filter passed to the Subscribe method, as with TopicQOSArray.
If the subscription is only for one topic, these lists would have only one value. If the number of elements in the string is less than the number of topic filters in the subscription, the final element will be applied to all remaining topics.
Subscription Options Example
mqtt1.Connected = true;
mqtt1.Config("TopicNLArray=true, false, true"); // TestTopic1 = true, TestTopic2 = false, TestTopic3 = true
mqtt1.Config("TopicRAPArray=false"); // TestTopic1 = false, TestTopic2 = false, TestTopic3 = false
mqtt1.Config("TopicRHArray=1, 0"); // // TestTopic1 = 1, TestTopic2 = 0, TestTopic3 = 0
mqtt1.Subscribe("TestTopic1, TestTopic2, TestTopic3", 1);
Subscription Identifiers
MQTT 5 allows clients to specify a numeric subscription identifier which will be returned with messages delivered for that subscription.
To do so with the class, set the SubscriptionIdentifier configuration setting before calling Subscribe. To update the identifier, call Subscribe with a new SubscriptionIdentifier.
To verify that a server supports subscription identifiers, check the "SubscriptionIdentifiersAvailable" value in the ConnAckProperties configuration setting. See the SubscriptionIdentifiers property of the MQTTMessage type for details on returning the ids associated with messages.
Note that a topic may have multiple identifiers associated with it (due to wildcards), and the same identifier may be associated with multiple topics.
Subscription Options Example
mqtt1.Connected = true;
mqtt1.OnMessageAck += (o, e) => {
String ids = mqtt1.IncomingMessages[e.Index].SubscriptionIdentifiers; // ids = "123,321"
};
mqtt1.Config("SubscriptionIdentifier=123");
mqtt1.Subscribe("test_topic/subtopic", 1);
mqtt1.Config("SubscriptionIdentifier=321");
mqtt1.Subscribe("test_topic/+", 1);
mqtt2.Connected = true;
mqtt2.PublishMessage("test_topic/subtopic", 1, "hello world");
Unsubscribe Method (IPWorksIoT_MQTT Class)
Unsubscribes the class from one or more topic filters.
Object Oriented Interface
public function doUnsubscribe($topicfilter);
Procedural Interface
ipworksiot_mqtt_do_unsubscribe($res, $topicfilter);
Remarks
This method unsubscribes the class from one or more topic filters. The string passed for TopicFilter must contain one or more valid topic filter strings, separated by the delimiter string specified by the TopicDelimiter configuration setting (, by default).
The Unsubscribed event will fire when the server has acknowledged the unsubscribe request. However, note that the server's acknowledgment doesn't specify which topics a client was unsubscribed from. Please refer to the Unsubscribed event for more information.
To successfully unsubscribe from a topic filter, the exact filter must be passed to Unsubscribe, regardless of whether or not if contains wildcards. The server ignores any topic filters in an unsubscribe request which do not exactly match that of an existing subscription.
It is impossible to partially unsubscribe from a topic filter with wildcards (that is, if a client is subscribed to a topic filter home/floor1/+/#, requesting to unsubscribe from a topic filter home/floor1/livingRoom/temperature does nothing).
Similarly, because topic filters in an unsubscribe request are simply compared character-by-character with existing subscriptions rather than being interpreted, it is not possible to perform an action such as unsubscribing from all currently subscribed topics by passing "#" for TopicFilter.
Unsubscribe Example
// Unsubscribe from topic filters; have to use the exact same strings as before. If this
// was to be called after calling the code example shown for the Subscribe() method, we
// would still be subscribed to the "home" topic filter.
mqtt1.Unsubscribe("home/floor1/+/temperature,home/floor2/#");
Connected Event (IPWorksIoT_MQTT Class)
This event is fired immediately after a connection completes (or fails).
Object Oriented Interface
public function fireConnected($param);
Procedural Interface
ipworksiot_mqtt_register_callback($res, 1, array($this, 'fireConnected'));
Parameter List
'statuscode'
'description'
Remarks
If the connection is made normally, StatusCode is 0 and Description is "OK".
If the connection fails, StatusCode has the error code returned by the Transmission Control Protocol (TCP)/IP stack. Description contains a description of this code. The value of StatusCode is equal to the value of the error.
Please refer to the Error Codes section for more information.
ConnectionStatus Event (IPWorksIoT_MQTT Class)
This event is fired to indicate changes in the connection state.
Object Oriented Interface
public function fireConnectionStatus($param);
Procedural Interface
ipworksiot_mqtt_register_callback($res, 2, array($this, 'fireConnectionStatus'));
Parameter List
'connectionevent'
'statuscode'
'description'
Remarks
The ConnectionStatus event is fired when the connection state changes: for example, completion of a firewall or proxy connection or completion of a security handshake.
The ConnectionEvent parameter indicates the type of connection event. Values may include the following:
Firewall connection complete. | |
Secure Sockets Layer (SSL) or S/Shell handshake complete (where applicable). | |
Remote host connection complete. | |
Remote host disconnected. | |
SSL or S/Shell connection broken. | |
Firewall host disconnected. |
Disconnected Event (IPWorksIoT_MQTT Class)
This event is fired when a connection is closed.
Object Oriented Interface
public function fireDisconnected($param);
Procedural Interface
ipworksiot_mqtt_register_callback($res, 3, array($this, 'fireDisconnected'));
Parameter List
'statuscode'
'description'
Remarks
If the connection is broken normally, StatusCode is 0 and Description is "OK".
If the connection is broken for any other reason, StatusCode has the error code returned by the Transmission Control Protocol (TCP/IP) subsystem. Description contains a description of this code. The value of StatusCode is equal to the value of the TCP/IP error.
Please refer to the Error Codes section for more information.
Error Event (IPWorksIoT_MQTT Class)
Information about errors during data delivery.
Object Oriented Interface
public function fireError($param);
Procedural Interface
ipworksiot_mqtt_register_callback($res, 4, array($this, 'fireError'));
Parameter List
'errorcode'
'description'
Remarks
The Error event is fired in case of exceptional conditions during message processing. Normally the class fails with an error.
The ErrorCode parameter contains an error code, and the Description parameter contains a textual description of the error. For a list of valid error codes and their descriptions, please refer to the Error Codes section.
Log Event (IPWorksIoT_MQTT Class)
Fires once for each log message.
Object Oriented Interface
public function fireLog($param);
Procedural Interface
ipworksiot_mqtt_register_callback($res, 5, array($this, 'fireLog'));
Parameter List
'loglevel'
'message'
'logtype'
Remarks
This event fires once for each log message generated by the class. The verbosity is controlled by the LogLevel setting.
LogLevel indicates the level of the Message. Possible values are:
0 (None) | No events are logged. |
1 (Info - default) | Informational events are logged. |
2 (Verbose) | Detailed data is logged. |
3 (Debug) | Debug data is logged. |
LogType identifies the type of log entry. Possible values are:
- Info: General information about the class.
- Packet: Packet content logging.
- Reconnect: Reconnection status messages.
- Session: Session status messages.
MessageAck Event (IPWorksIoT_MQTT Class)
Fired when an incoming or outgoing message has completed all acknowledgment steps.
Object Oriented Interface
public function fireMessageAck($param);
Procedural Interface
ipworksiot_mqtt_register_callback($res, 6, array($this, 'fireMessageAck'));
Parameter List
'packetid'
'direction'
'index'
'responsecode'
Remarks
The MessageAck event fires once an incoming or outgoing message with a QoS of 1 or 2 has successfully completed all acknowledgment steps as required by its QoS level. (Note that this event does not fire for messages with a QoS of 0 since they do not require acknowledgment.)
- PacketId: The Id of the original PUBLISH packet for the message.
- Direction: Shows whether the client (0) or the server (1) is sending the data.
- Index: The index at which the message resides in either the IncomingMessage* properties or OutgoingMessage* properties.
- ResponseCode: In MQTT 5, all response packets contain Reason Codes. This argument contains any code encountered in message acknowledgment packets (PUBACK, PUBREC, PUBREL, PUBCOMP).
Possible MQTT-specific values for ResponseCode are:
Value | Applicable packets | Description |
0 | PUBACK, PUBREC, PUBREL, PUBCOMP | Success |
16 | PUBACK, PUBREC | No matching subscribers |
128 | PUBACK, PUBREC | Unspecified error |
131 | PUBACK, PUBREC | Implementation specific error |
135 | PUBACK, PUBREC | Not authorized |
144 | PUBACK, PUBREC | Topic Name invalid |
145 | PUBACK, PUBREC | Packet Identifier in use |
146 | PUBREL, PUBCOMP | Packet Identifier not found |
Inbound Message Processing
Incoming messages with a QoS of 1 follow these steps:
- The message is added to IncomingMessage* when the class receives the PUBLISH packet.
- The class sends a PUBACK (publish acknowledgment) packet in response.
- The MessageAck event is fired.
- The message is removed from IncomingMessage*.
- The MessageIn event is fired.
Incoming messages with a QoS of 2 follow these steps:
- The message is added to IncomingMessage* when the class receives the PUBLISH packet.
- The class sends a PUBREC (publish received) packet in response.
- The class waits to receive a PUBREL (publish release) packet.
- The class sends a PUBCOMP (publish complete) packet in response.
- The MessageAck event is fired.
- The message is removed from IncomingMessage*.
- The MessageIn event is fired.
Outbound Message Processing
Outgoing messages with a QoS of 1 follow these steps:
- The class sends the PUBLISH packet, then adds the message to OutgoingMessage*.
- The class waits to receive a PUBACK (publish acknowledgment) packet.
- The MessageAck event is fired.
- The message is removed from OutgoingMessage*.
- The MessageOut event is fired.
Outgoing messages with a QoS of 2 follow these steps:
- The class sends the PUBLISH packet, then adds the message to OutgoingMessage*.
- The class waits to receive a PUBREC (publish received) packet.
- The class sends a PUBREL (publish release) packet in response.
- The class waits to receive a PUBCOMP (publish complete) packet.
- The MessageAck event is fired.
- The message is removed from OutgoingMessage*.
- The MessageOut event is fired.
In MQTT 3.1.1, the RepublishInterval configuration setting, if set to a non-zero value (default), controls how long the class will wait to receive a PUBACK (for QoS 1) or PUBREC (for QoS 2) before automatically republishing an outgoing message. In MQTT 5, messages are only republished if the client is disconnected before receiving a PUBACK or PUBREC.
MessageIn Event (IPWorksIoT_MQTT Class)
Fired when an incoming message has been received and/or fully acknowledged.
Object Oriented Interface
public function fireMessageIn($param);
Procedural Interface
ipworksiot_mqtt_register_callback($res, 7, array($this, 'fireMessageIn'));
Parameter List
'packetid'
'topic'
'qos'
'message'
'retained'
'duplicate'
Remarks
The MessageIn event fires once for each incoming message either immediately after it is received (QoS 0), or after it has been fully acknowledged (QoS 1 and 2).
- PacketId: The message packet Id. This will always be -1 if QOS is 0.
- Topic: The message's topic string.
- QOS: The message's QoS level.
- Message: The message data.
- Retained: Whether or not this message was received as a result of subscribing to a topic.
- Duplicate: Whether or not the server has indicated that this message is a duplicate of another message sent previously.
Refer to MessageAck for more information about QoS 1 and 2 message processing steps.
// MessageIn event handler.
mqtt1.OnMessageIn += (s, e) => {
Console.WriteLine("Received message from topic '" + e.Topic + "' with QoS " + e.QOS + ":");
Console.WriteLine(e.Message);
};
MessageOut Event (IPWorksIoT_MQTT Class)
Fired when an outgoing message has been sent and/or fully acknowledged.
Object Oriented Interface
public function fireMessageOut($param);
Procedural Interface
ipworksiot_mqtt_register_callback($res, 8, array($this, 'fireMessageOut'));
Parameter List
'packetid'
'topic'
'qos'
'message'
'retained'
'duplicate'
Remarks
The MessageOut event fires once for each outgoing message either immediately after it is sent (QoS 0), or after it has been fully acknowledged by the receiver (QoS 1 and 2).
- PacketId: The message packet Id. This will always be -1 if QOS is 0.
- Topic: The message's topic string.
- QOS: The message's QoS level.
- Message: The message data.
- Retained: Whether or not this message was sent with the "Retain" flag set.
- Duplicate: Whether or not this message was sent with the "Duplicate" flag set.
Refer to MessageAck for more information about QoS 1 and 2 message processing steps.
// MessageOut event handler.
mqtt1.OnMessageOut += (s, e) => {
Console.WriteLine("Send message to topic '" + e.Topic + "' with QoS " + e.QOS + ":");
Console.WriteLine(e.Message);
};
ReadyToSend Event (IPWorksIoT_MQTT Class)
Fired when the class is ready to send data.
Object Oriented Interface
public function fireReadyToSend($param);
Procedural Interface
ipworksiot_mqtt_register_callback($res, 9, array($this, 'fireReadyToSend'));
Parameter List
Remarks
The ReadyToSend event indicates that the underlying TCP/IP subsystem is ready to accept data after a call to PublishData or PublishMessage fails due to a WOULDBLOCK condition. The event is also fired immediately after a connection to the remote host is established.
SSLServerAuthentication Event (IPWorksIoT_MQTT Class)
Fired after the server presents its certificate to the client.
Object Oriented Interface
public function fireSSLServerAuthentication($param);
Procedural Interface
ipworksiot_mqtt_register_callback($res, 10, array($this, 'fireSSLServerAuthentication'));
Parameter List
'certencoded'
'certsubject'
'certissuer'
'status'
'accept'
Remarks
During this event, the client can decide whether or not to continue with the connection process. The Accept parameter is a recommendation on whether to continue or close the connection. This is just a suggestion: application software must use its own logic to determine whether or not to continue.
When Accept is False, Status shows why the verification failed (otherwise, Status contains the string OK). If it is decided to continue, you can override and accept the certificate by setting the Accept parameter to True.
SSLStatus Event (IPWorksIoT_MQTT Class)
Shows the progress of the secure connection.
Object Oriented Interface
public function fireSSLStatus($param);
Procedural Interface
ipworksiot_mqtt_register_callback($res, 11, array($this, 'fireSSLStatus'));
Parameter List
'message'
Remarks
The event is fired for informational and logging purposes only. This event tracks the progress of the connection.
Subscribed Event (IPWorksIoT_MQTT Class)
Fires for each topic filter subscription the server acknowledges.
Object Oriented Interface
public function fireSubscribed($param);
Procedural Interface
ipworksiot_mqtt_register_callback($res, 12, array($this, 'fireSubscribed'));
Parameter List
'topicfilter'
'qos'
'responsecode'
Remarks
This event fires each time the server has acknowledged a topic filter subscription request (that is, calling Subscribe with multiple topic filters will cause this to fire multiple times).
- TopicFilter: The topic filter subscription request being acknowledged.
- QOS: The QoS level the server has granted for the subscription.
- ResponseCode: Indicates the result of the subscription request.
Possible values for ResponseCode are:
- 0: Success, QoS 0 granted
- 1: Success, QoS 1 granted
- 2: Success, QoS 2 granted
- 128: Unspecified error
- 131: Implementation specific error; The SUBSCRIBE is valid but the Server does not accept it.
- 135: Not authorized; The Client is not authorized to make this subscription.
- 143: Topic Filter invalid; The Topic Filter is correctly formed but is not allowed for this Client.
- 145: Packet Identifier in use
- 151: Quota exceeded; An implementation or administrative imposed limit has been exceeded.
- 158: Shared Subscriptions not supported
- 161: Shared Subscriptions not supported
- 162: Wildcard Subscriptions not supported
Keep in mind that the server may have chosen to grant a lower QoS than was requested under certain circumstances (e.g., if the server doesn't support the requested QoS).
Note: the server is not required to acknowledge a subscription before it begins delivering messages for that subscription.
Unsubscribed Event (IPWorksIoT_MQTT Class)
Fires when the server has acknowledged an unsubscribe request.
Object Oriented Interface
public function fireUnsubscribed($param);
Procedural Interface
ipworksiot_mqtt_register_callback($res, 13, array($this, 'fireUnsubscribed'));
Parameter List
'topicfilters'
'responsecode'
Remarks
This event fires when the server has acknowledged an unsubscribe request sent with Unsubscribe (that is, unlike the Subscribed event, this event fires only once for each call to Unsubscribe, regardless of how many topic filters are passed to it).
Note that in MQTT 3.1.1, servers do not specify which topic filters a client has been successfully unsubscribed in their acknowledgments. In fact, they will still acknowledge an unsubscribe request even if none of the topic filters included matched existing subscriptions. It is up to the client to keep track of what topics it is subscribed to; the TopicFilters parameter is provided as a convenience, its value simply a copy of the value passed to Unsubscribe originally.
Possible values for ResponseCode are:
- 0: Success; The subscription is deleted.
- 17: No subscription existed; No matching Topic Filter is being used by the Client.
- 128: Unspecified error; The unsubscribe could not be completed and the Server either does not wish to reveal the reason or none of the other Reason Codes apply.
- 131: Implementation specific error; The UNSUBSCRIBE is valid but the Server does not accept it.
- 135: Not authorized; The Client is not authorized to unsubscribe.
- 143: Topic Filter invalid; The Topic Filter is correctly formed but is not allowed for this Client.
- 145: Packet Identifier in use; The specified Packet Identifier is already in use.
Config Settings (MQTT Class)
The class accepts one or more of the following configuration settings. Configuration settings are similar in functionality to properties, but they are rarely used. In order to avoid "polluting" the property namespace of the class, access to these internal properties is provided through the Config method.MQTT Config Settings
This value is sent to the server in the CONNECT packet and must be set before calling Connect. It is also available in the ConnectProperties config. See the TopicAlias config for more details.
Valid only for MQTT 5.
The values listed below are available. If a value is absent in the CONNACK packet, the client should treat its value as the default listed.
Name | Type | Default | Description |
AssignedClientIdentifier | String | N/A | The Client Identifier which was assigned by the Server because a zero length Client Identifier was found in the CONNECT packet. |
MaximumQoS | Integer | 2 | The maximum accepted QoS of PUBLISH packets to be received by the server. |
MaximumPacketSize | Integer | Unlimited | Maximum packet size in bytes the server is willing to accept. |
ReasonString | String | N/A | A human readable string designed for diagnostics. |
ReceiveMaximum | Integer | 65,535 | Number of QoS 1 and QoS 2 publications the server is willing to process concurrently for the client. |
ResponseInformation | String | N/A | String used as the basis for creating a Response Topic. |
RetainAvailable | Boolean | True | Indicates whether the client may send PUBLISH packets with Retain set to True. |
ServerKeepAlive | Integer | Value in CONNECT | Keep Alive time assigned by server. If specified by server this value overrides the value requested by the client. |
ServerTopicAliasMax | Integer | 0 | See ServerTopicAliasMax. |
SessionExpInterval | Integer | Value in CONNECT | Defines the length of time for which the client and server must store session state data after disconnection. If included in the CONNACK and different than the SessionExpInterval which the client requested in the CONNECT packet, this value overrides the client-requested value and must be followed by the client. |
SharedSubscriptionAvailable | Boolean | True | Indicates whether the server supports shared subscriptions. |
SubscriptionIdentifiersAvailable | Boolean | True | Indicates whether the server supports subscription identifiers. |
WildcardSubscriptionAvaiable | Boolean | True | Indicates whether the server supports wildcard subscriptions. |
Read-only. Valid only for MQTT 5.
To reset an individual value so that it is no longer included in the CONNECT packet (after it has previously been set), set it to "", or -1 for integers. To reset all ConnectProperties values, set the config JSON string to "".
Name | Type | Default | Description |
ClientTopicAliasMax | Integer | 0 | See ClientTopicAliasMax. |
MaximumPacketSize | Integer | Unlimited | Maximum Packet Size the Client is willing to accept (cannot be 0). |
ReceiveMaximum | Integer | 65,535 | The number of QoS 1 and QoS 2 publications the client is willing to process concurrently. |
RequestProblemInformation | Boolean | True | Indicates the server is allowed to return a Reason String and or User Properties on packets other than PUBLISH, CONNACK or DISCONNECT. |
RequestResponseInformation | Boolean | False | Indicates the client requests the server to return response information in the CONNACK packet. |
SessionExpInterval | Integer | 0 | See SessionExpInterval. |
To set these values, set the ConnectProperties config to a string JSON object containing one or more key/value pairs to set. For example, to set all values:
{ "ClientTopicAliasMax":"20", "MaximumPacketSize":"128000", "ReceiveMaximum":"12", "RequestResponseInformation":"false", "RequestProblemInformation":"true", "SessionExpInterval":"1234" }
Valid only for MQTT 5.
Supported properties are:
Name | Type | Default | Description |
SessionExpInterval | Integer | Value in CONNECT | Can only be sent by client. A new length of time for the client and server to store session state data. Cannot be non-zero if the client set it to zero in the CONNECT packet. If absent, the client and server should use the value specified in the CONNECT packet. |
ReasonString | String | N/A | A human readable string designed for diagnostics. |
To reset an individual value so that it is no longer included in the DISCONNECT packet (after it has previously been set), set it to "", or -1 for integers. To reset all DisconnectProperties values, set the config JSON string to "".
Valid only for MQTT 5.
To specify a code as the client, set this value before calling Disconnect.
This value will be populated when the class receives a DISCONNECT packet from the server.
For a full list of values applicable to be sent by the client, server or both, see the MQTT 5 specification. They include:
- 0x00: Normal disconnection - Close the connection normally. Do not send the Will Message.
- 0x04: Disconnect with Will Message (Client only) - The Client wishes to disconnect but requires that the Server also publishes its Will Message.
- 0x80: Unspecified error - The Connection is closed but the sender either does not wish to reveal the reason, or none of the other Reason Codes apply.
Valid only for MQTT 5.
This setting is ignored when messages are published with a QoS of 0.
Note: The Duplicate flag in an MQTT PUBLISH packet refers to the Id of the packet, not the message itself. According to the MQTT specification, it is possible (and perfectly legal) that a client could receive two QoS 1 PUBLISH packets with different Ids despite having the exact same message data.
Read-only. Valid only for MQTT 5.
Read-only. Valid only for MQTT 5.
Read-only. Valid only for MQTT 5.
0 (None) | No events are logged. |
1 (Info - default) | Informational events are logged. |
2 (Verbose) | Detailed data is logged. |
3 (Debug) | Debug data is logged. |
To reset an individual value so that it is no longer included in the PUBLISH packet (after it has previously been set), set it to "", or -1 for integers. To reset all OutgoingMessageProperties values, set the config JSON string to "".
Name | Type | Default | Description |
ContentType | String | N/A | String describing content of message to be sent to all subscribers receiving the message. |
CorrelationData | String | N/A | Hex-encoded binary string used by the sender of a request message to identify which request the response message is for when received (See ResponseTopic). |
MessageExpInterval | Integer | No exp. | Length of time after which the server must stop delivery to a subscriber if not yet processed. |
PayloadFormatIndicator | Integer | 0x00 | 0x00 = unspecified bytes. 0x01 = UTF-8 encoded character data. Sent to all subscribers receiving the message. |
ResponseTopic | String | N/A | See ResponseTopic. |
TopicAlias | Integer | N/A | See TopicAlias. |
UserProperty | String | "" | String key:value pair to be included in the header properties. The UserProperty can appear multiple times to represent multiple name, value pairs. |
To set these values, set the OutgoingMessageProperties config to a string JSON object containing one or more key/value pairs to set. For example:
{ "ContentType":"plain/text", "CorrelationData":"00000000", "MessageExpInterval":"1000", "PayloadFormatIndicator":"1", "ResponseTopic": "ResponseTopic", "TopicAlias":"1", "UserProperty":"prp1:val1", "UserProperty":"prp2:val2" }Valid only for MQTT 5.
By default, this setting is 0 and no User Properties are sent in the outgoing message.
Code Example
mqtt1.Connected = true;
mqtt.Config("OutgoingUserPropCount=1");
mqtt.Config("OutgoingUserPropName[0]=prp1");
mqtt.Config("OutgoingUserPropValue[0]=val1");
mqtt1.PublishMessage(topic, 1, "hello");
Valid only for MQTT 5.
The size of this array is controlled by the OutgoingUserPropCount configuration setting.
Valid only for MQTT 5.
The size of this array is controlled by the OutgoingUserPropCount configuration setting.
Valid only for MQTT 5.
The default RepublishInterval is 60 seconds. Specify a RepublishInterval of 0 to prevent the class from automatically republishing messages.
In MQTT 5, messages are only republished if the client is disconnected before receiving a PUBACK or PUBREC. This property is only valid for MQTT 3.1.1.
To send a Request Message, set this value before calling PublishMessage.
To reset the value once it has been previously set, so that it is no longer included in future packets, set it to "".
ResponseTopic and Correlation Data are also accessible in the OutgoingMessageProperties config.
Valid only for MQTT 5.
Publishing a non-empty message with the Retain flag set and a non-zero QoS will cause the server to store it (replacing any previously retained message in the process) so that it can be delivered to any clients which subscribe to the topic in the future. (If the QoS is 0, the server can store the message, but it is not required to do so indefinitely, if at all.)
If the class publishes an empty message with the Retain flag set, then (regardless of its QoS) the server will remove any previously retained message for the topic.
Note that messages with the Retain flag set are still processed by the server and delivered as usual to clients currently subscribed to the topic, regardless of whether they are empty or not. Also note that retained messages are not part of a session's state, they are retained until they are either removed or replaced by another retained message, regardless of whether or not the client connected with CleanSession set to True.
MQTT 5 Notes
In MQTT 5, the "RetainAvailable" value in the ConnAckProperties config indicates whether the client may send messages with the Retain flag set to True.
This property is also accessible in the ConnAckProperties config.
Read-only. Valid only for MQTT 5.
The server may return a different Session Expiration Interval in the ConnAckProperties, overriding this value. Additionally, the client may send a new value in the DisconnectProperties (as long as it was not 0 originally).
See CleanSession for more details on stored sessions in MQTT 5. This property also available in ConnectProperties.
Valid only for MQTT 5.
If CleanSession is True when Connect is called, this will always return False.
Note that this value applies only to SUBSCRIBE packets and not to outgoing or incoming messages. The client is not permitted to send a PUBLISH packet with a subscription id - the server will include it when it sends PUBLISH packets to subscribing clients if those clients have established ids. To access subscription ids of incoming messages, see the "SubscriptionIdentifiers" field in the MQTTMessage type.
To reset the value once it has been previously set, so that it is no longer included in future packets, set it to -1.
See the Subscribe method for details on subscription identifiers. Valid only for MQTT 5.
A sender can modify the Topic Alias mapping by sending another PUBLISH in the same Network Connection with the same Topic Alias value and a different non-zero length Topic Name.
Note that a topic alias must have a value greater than zero and less than or equal to ServerTopicAliasMax. Topic alias mappings exist only within a connection and are not a part of stored session state data. The Topic Alias mappings used by the Client and Server are independent from each other.
To reset the value once it has been previously set, so that it is no longer included in future packets, set it to -1.
Also accessible in the OutgoingMessageProperties config.
Code Example
mqtt1.Connected = true;
mqtt1.Config("TopicAlias=1"); // map 1 to topic "PublishWithTopicAlias"
mqtt1.PublishMessage(topic, 1, "hello");
mqtt1.Config("TopicAlias=1"); // set topic alias 1 to publish with empty topic filter
mqtt1.PublishMessage("", 1, "hello");
Valid only for MQTT 5.
For topic filters subscribed to with a True flag, messages will not be forwarded to the same ClientId they were published from.
By default, this value is empty and all flags are False.
See the Subscribe method for more details on Subscription Options. Valid only for MQTT 5.
If this setting is set to the empty string (default) when Subscribe is called with multiple topic filters, the class will use the QoS value passed to Subscribe for all of them.
For topic filters subscribed to with a True flag, messages forwarded for this subscription will keep the retain flag they were published with (as opposed to always being set to False).
By default, this value is empty and all flags are False.
See the Subscribe method for more details on Subscription Options. Valid only for MQTT 5.
- 0 = send retained messages at the time of the subscribe
- 1 = send retained messages at subscribe only if the subscription does not currently exist
- 2 = do not send retained messages at the time of the subscribe
By default, this value is empty and all values are 0.
See the Subscribe method for more details on Subscription Options. Valid only for MQTT 5.
To reset an individual value so that it is no longer included in the CONNECT packet (after it has previously been set), set it to "", or -1 for integers. To reset all WillProperties values, set the config JSON string to "".
Name | Type | Default | Description |
ContentType | String | N/A | String describing content of will message. |
CorrelationData | String | N/A | Hex-encoded binary string used by the sender of a request message to identify which request the response message is for when received. |
MessageExpInterval | Integer | No exp. | Length of time after which the server must stop delivery of the will message to a subscriber if not yet processed. |
PayloadFormatIndicator | Integer | 0x00 | 0x00 = unspecified bytes. |
ReponseTopic | String | N/A | Used as a topic name for a response message. |
WillDelayInterval | Integer | 0 | Delay in seconds after disconnection until the server should publish the client WillMessage. |
Note that these values will be ignored if WillTopic is empty.
To set these values, set the ConnectProperties config to a string JSON object containing one or more key/value pairs to set. For example, to set all values:
{ "ContentType":"text/plain", "CorrelationData":"00000000", "MessageExpInterval":"3600", "PayloadFormatIndicator":"1", "ResponseTopic": "ResponseTopic", "WillDelayInterval":"10" }
Valid only for MQTT 5.
Refer to WillTopic for more information.
See Retain for general information about how retained messages are handled by the server.
Refer to WillTopic for more information.
TCPClient Config Settings
If the FirewallHost setting is set to a Domain Name, a DNS request is initiated. Upon successful termination of the request, the FirewallHost setting is set to the corresponding address. If the search is not successful, an error is returned.
Note: This setting is provided for use by classs that do not directly expose Firewall properties.
Note: This setting is provided for use by classs that do not directly expose Firewall properties.
Note: This configuration setting is provided for use by classs that do not directly expose Firewall properties.
0 | No firewall (default setting). |
1 | Connect through a tunneling proxy. FirewallPort is set to 80. |
2 | Connect through a SOCKS4 Proxy. FirewallPort is set to 1080. |
3 | Connect through a SOCKS5 Proxy. FirewallPort is set to 1080. |
10 | Connect through a SOCKS4A Proxy. FirewallPort is set to 1080. |
Note: This setting is provided for use by classs that do not directly expose Firewall properties.
Note: This setting is provided for use by classs that do not directly expose Firewall properties.
Note: This value is not applicable in macOS.
In the case that Linger is True (default), two scenarios determine how long the connection will linger. In the first, if LingerTime is 0 (default), the system will attempt to send pending data for a connection until the default IP timeout expires.
In the second scenario, if LingerTime is a positive value, the system will attempt to send pending data until the specified LingerTime is reached. If this attempt fails, then the system will reset the connection.
The default behavior (which is also the default mode for stream sockets) might result in a long delay in closing the connection. Although the class returns control immediately, the system could hold system resources until all pending data are sent (even after your application closes).
Setting this property to False forces an immediate disconnection. If you know that the other side has received all the data you sent (e.g., by a client acknowledgment), setting this property to False might be the appropriate course of action.
In multi-homed hosts (machines with more than one IP interface) setting LocalHost to the value of an interface will make the class initiate connections (or accept in the case of server classs) only through that interface.
If the class is connected, the LocalHost setting shows the IP address of the interface through which the connection is made in internet dotted format (aaa.bbb.ccc.ddd). In most cases, this is the address of the local host, except for multi-homed hosts (machines with more than one IP interface).
Setting this to 0 (default) enables the system to choose a port at random. The chosen port will be shown by LocalPort after the connection is established.
LocalPort cannot be changed once a connection is made. Any attempt to set this when a connection is active will generate an error.
This; setting is useful when trying to connect to services that require a trusted port in the client side. An example is the remote shell (rsh) service in UNIX systems.
If an EOL string is found in the input stream before MaxLineLength bytes are received, the DataIn event is fired with the EOL parameter set to True, and the buffer is reset.
If no EOL is found, and MaxLineLength bytes are accumulated in the buffer, the DataIn event is fired with the EOL parameter set to False, and the buffer is reset.
The minimum value for MaxLineLength is 256 bytes. The default value is 2048 bytes.
www.google.com;www.nsoftware.com
Note: This value is not applicable in Java.
By default, this config is set to false.
0 | IPv4 Only |
1 | IPv6 Only |
2 | IPv6 with IPv4 fallback |
SSL Config Settings
When enabled, SSL packet logs are output using the SSLStatus event, which will fire each time an SSL packet is sent or received.
Enabling this setting has no effect if SSLProvider is set to Platform.
The path set by this property should point to a directory containing CA certificates in PEM format. The files each contain one CA certificate. The files are looked up by the CA subject name hash value, which must hence be available. If more than one CA certificate with the same name hash value exist, the extension must be different (e.g. 9d66eef0.0, 9d66eef0.1 etc). OpenSSL recommends to use the c_rehash utility to create the necessary links. Please refer to the OpenSSL man page SSL_CTX_load_verify_locations(3) for details.
The file set by this property should contain a list of CA certificates in PEM format. The file can contain several CA certificates identified by
-----BEGIN CERTIFICATE-----
... (CA certificate in base64 encoding) ...
-----END CERTIFICATE-----
sequences. Before, between, and after the certificates text is allowed which can be used e.g. for descriptions of the certificates. Please refer to the OpenSSL man page SSL_CTX_load_verify_locations(3) for details.
The format of this string is described in the OpenSSL man page ciphers(1) section "CIPHER LIST FORMAT". Please refer to it for details. The default string "DEFAULT" is determined at compile time and is normally equivalent to "ALL:!ADH:RC4+RSA:+SSLv2:@STRENGTH".
By default OpenSSL uses the device file "/dev/urandom" to seed the PRNG and setting OpenSSLPrngSeedData is not required. If set, the string specified is used to seed the PRNG.
If set to true, the class will reuse the context if and only if the following criteria are met:
- The target host name is the same.
- The system cache entry has not expired (default timeout is 10 hours).
- The application process that calls the function is the same.
- The logon session is the same.
- The instance of the class is the same.
The value is formatted as a list of paths separated by semicolons. The class will check for the existence of each file in the order specified. When a file is found the CA certificates within the file will be loaded and used to determine the validity of server or client certificates.
The default value is:
/etc/ssl/ca-bundle.pem;/etc/pki/tls/certs/ca-bundle.crt;/etc/ssl/certs/ca-certificates.crt;/etc/pki/tls/cacert.pem
-----BEGIN CERTIFICATE----- MIIEKzCCAxOgAwIBAgIRANTET4LIkxdH6P+CFIiHvTowDQYJKoZIhvcNAQELBQAw ... eWHV5OW1K53o/atv59sOiW5K3crjFhsBOd5Q+cJJnU+SWinPKtANXMht+EDvYY2w F0I1XhM+pKj7FjDr+XNj -----END CERTIFICATE----- \r \n -----BEGIN CERTIFICATE----- MIIEFjCCAv6gAwIBAgIQetu1SMxpnENAnnOz1P+PtTANBgkqhkiG9w0BAQUFADBp .. d8q23djXZbVYiIfE9ebr4g3152BlVCHZ2GyPdjhIuLeH21VbT/dyEHHA -----END CERTIFICATE-----
When set to 0 (default) the CRL check will not be performed by the class. When set to 1, it will attempt to perform the CRL check, but will continue without an error if the server's certificate does not support CRL. When set to 2, it will perform the CRL check and will throw an error if CRL is not supported.
This configuration setting is only supported in the Java, C#, and C++ editions. In the C++ edition, it is only supported on Windows operating systems.
When set to 0 (default) the class will not perform an OCSP check. When set to 1, it will attempt to perform the OCSP check, but will continue without an error if the server's certificate does not support OCSP. When set to 2, it will perform the OCSP check and will throw an error if OCSP is not supported.
This configuration setting is only supported in the Java, C#, and C++ editions. In the C++ edition, it is only supported on Windows operating systems.
Please note that this setting contains the minimum cipher strength requested from the security library. The actual cipher strength used for the connection is shown by the SSLStatus event.
Use this setting with caution. Requesting a lower cipher strength than necessary could potentially cause serious security vulnerabilities in your application.
When the provider is OpenSSL, SSLCipherStrength is currently not supported. This functionality is instead made available through the OpenSSLCipherList config setting.
By default, the enabled cipher suites will include all available ciphers ("*").
The special value "*" means that the class will pick all of the supported cipher suites. If SSLEnabledCipherSuites is set to any other value, only the specified cipher suites will be considered.
Multiple cipher suites are separated by semicolons.
Example values when SSLProvider is set to Platform:
obj.config("SSLEnabledCipherSuites=*");
obj.config("SSLEnabledCipherSuites=CALG_AES_256");
obj.config("SSLEnabledCipherSuites=CALG_AES_256;CALG_3DES");
Possible values when SSLProvider is set to Platform include:
- CALG_3DES
- CALG_3DES_112
- CALG_AES
- CALG_AES_128
- CALG_AES_192
- CALG_AES_256
- CALG_AGREEDKEY_ANY
- CALG_CYLINK_MEK
- CALG_DES
- CALG_DESX
- CALG_DH_EPHEM
- CALG_DH_SF
- CALG_DSS_SIGN
- CALG_ECDH
- CALG_ECDH_EPHEM
- CALG_ECDSA
- CALG_ECMQV
- CALG_HASH_REPLACE_OWF
- CALG_HUGHES_MD5
- CALG_HMAC
- CALG_KEA_KEYX
- CALG_MAC
- CALG_MD2
- CALG_MD4
- CALG_MD5
- CALG_NO_SIGN
- CALG_OID_INFO_CNG_ONLY
- CALG_OID_INFO_PARAMETERS
- CALG_PCT1_MASTER
- CALG_RC2
- CALG_RC4
- CALG_RC5
- CALG_RSA_KEYX
- CALG_RSA_SIGN
- CALG_SCHANNEL_ENC_KEY
- CALG_SCHANNEL_MAC_KEY
- CALG_SCHANNEL_MASTER_HASH
- CALG_SEAL
- CALG_SHA
- CALG_SHA1
- CALG_SHA_256
- CALG_SHA_384
- CALG_SHA_512
- CALG_SKIPJACK
- CALG_SSL2_MASTER
- CALG_SSL3_MASTER
- CALG_SSL3_SHAMD5
- CALG_TEK
- CALG_TLS1_MASTER
- CALG_TLS1PRF
obj.config("SSLEnabledCipherSuites=*");
obj.config("SSLEnabledCipherSuites=TLS_DHE_DSS_WITH_AES_128_CBC_SHA");
obj.config("SSLEnabledCipherSuites=TLS_DHE_DSS_WITH_AES_128_CBC_SHA;TLS_DH_ANON_WITH_AES_128_CBC_SHA");
Possible values when SSLProvider is set to Internal include:
- TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384
- TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256
- TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256
- TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384
- TLS_ECDH_ECDSA_WITH_AES_256_GCM_SHA384
- TLS_RSA_WITH_AES_256_GCM_SHA384
- TLS_RSA_WITH_AES_128_GCM_SHA256
- TLS_ECDH_ECDSA_WITH_AES_128_GCM_SHA256
- TLS_DHE_DSS_WITH_AES_256_GCM_SHA384
- TLS_DHE_RSA_WITH_AES_256_GCM_SHA384
- TLS_ECDH_RSA_WITH_AES_256_GCM_SHA384
- TLS_ECDH_RSA_WITH_AES_128_GCM_SHA256
- TLS_DHE_RSA_WITH_AES_128_GCM_SHA256
- TLS_DHE_DSS_WITH_AES_128_GCM_SHA256
- TLS_DH_RSA_WITH_AES_128_GCM_SHA256 (Not Recommended)
- TLS_DH_RSA_WITH_AES_256_GCM_SHA384 (Not Recommended)
- TLS_DH_DSS_WITH_AES_128_GCM_SHA256 (Not Recommended)
- TLS_DH_DSS_WITH_AES_256_GCM_SHA384 (Not Recommended)
- TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA384
- TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256
- TLS_ECDH_ECDSA_WITH_AES_256_CBC_SHA384
- TLS_DHE_DSS_WITH_AES_256_CBC_SHA256
- TLS_RSA_WITH_AES_256_CBC_SHA256
- TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384
- TLS_ECDH_RSA_WITH_AES_256_CBC_SHA384
- TLS_DHE_RSA_WITH_AES_256_CBC_SHA256
- TLS_DHE_RSA_WITH_AES_128_CBC_SHA256
- TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256
- TLS_RSA_WITH_AES_128_CBC_SHA256
- TLS_ECDH_ECDSA_WITH_AES_128_CBC_SHA256
- TLS_ECDH_RSA_WITH_AES_128_CBC_SHA256
- TLS_DHE_DSS_WITH_AES_128_CBC_SHA256
- TLS_RSA_WITH_AES_256_CBC_SHA
- TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA
- TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA
- TLS_ECDH_ECDSA_WITH_AES_256_CBC_SHA
- TLS_DHE_RSA_WITH_AES_256_CBC_SHA
- TLS_ECDH_RSA_WITH_AES_256_CBC_SHA
- TLS_DHE_DSS_WITH_AES_256_CBC_SHA
- TLS_RSA_WITH_AES_128_CBC_SHA
- TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA
- TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA
- TLS_ECDH_ECDSA_WITH_AES_128_CBC_SHA
- TLS_ECDH_RSA_WITH_AES_128_CBC_SHA
- TLS_DHE_RSA_WITH_AES_128_CBC_SHA
- TLS_DHE_DSS_WITH_AES_128_CBC_SHA
- TLS_ECDHE_ECDSA_WITH_3DES_EDE_CBC_SHA
- TLS_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA
- TLS_ECDH_ECDSA_WITH_3DES_EDE_CBC_SHA
- TLS_ECDH_RSA_WITH_3DES_EDE_CBC_SHA
- TLS_DHE_RSA_WITH_3DES_EDE_CBC_SHA
- TLS_DHE_DSS_WITH_3DES_EDE_CBC_SHA
- TLS_RSA_WITH_3DES_EDE_CBC_SHA
- TLS_RSA_WITH_DES_CBC_SHA
- TLS_DHE_RSA_WITH_DES_CBC_SHA
- TLS_DHE_DSS_WITH_DES_CBC_SHA
- TLS_RSA_WITH_RC4_128_MD5
- TLS_RSA_WITH_RC4_128_SHA
When TLS 1.3 is negotiated (see SSLEnabledProtocols) only the following cipher suites are supported:
- TLS_AES_256_GCM_SHA384
- TLS_CHACHA20_POLY1305_SHA256
- TLS_AES_128_GCM_SHA256
SSLEnabledCipherSuites is used together with SSLCipherStrength.
Not all supported protocols are enabled by default (the value of this setting is 4032). If you want more granular control over the enabled protocols, you can set this property to the binary 'OR' of one or more of the following values:
TLS1.3 | 12288 (Hex 3000) |
TLS1.2 | 3072 (Hex C00) (Default) |
TLS1.1 | 768 (Hex 300) (Default) |
TLS1 | 192 (Hex C0) (Default) |
SSL3 | 48 (Hex 30) [Platform Only] |
SSL2 | 12 (Hex 0C) [Platform Only] |
SSLEnabledProtocols - TLS 1.3 Notes
By default when TLS 1.3 is enabled the class will use the internal TLS implementation when the SSLProvider is set to Automatic for all editions.
In editions which are designed to run on Windows SSLProvider can be set to Platform to use the platform implementation instead of the internal implementation. When configured in this manner, please note that the platform provider is only supported on Windows 11 / Windows Server 2022 and up. The default internal provider is available on all platforms and is not restricted to any specific OS version.
If set to 1 (Platform provider) please be aware of the following notes:
- The platform provider is only available on Windows 11 / Windows Server 2022 and up.
- SSLEnabledCipherSuites and other similar SSL configuration settings are not supported.
- If SSLEnabledProtocols includes both TLS 1.3 and TLS 1.2 the above restrictions are still applicable even if TLS 1.2 is negotiated. Enabling TLS 1.3 with the platform provider changes the implementation used for all TLS versions.
SSLEnabledProtocols: SSL2 and SSL3 Notes:
SSL 2.0 and 3.0 are not supported by the class when the SSLProvider is set to internal. To use SSL 2.0 or SSL 3.0, the platform security API must have the protocols enabled and SSLProvider needs to be set to platform.
This setting is only applicable when SSLProvider is set to Internal.
If set to True all certificates returned by the server will be present in the Encoded parameter of the SSLServerAuthentication event. This includes the leaf certificate, any intermediate certificate, and the root certificate.
When set, the class will save the session secrets in the same format as the SSLKEYLOGFILE environment variable functionality used by most major browsers and tools such as Chrome, Firefox, and cURL. This file can then be used in tools such as Wireshark to decrypt TLS traffice for debugging purposes. When writing to this file the class will only append, it will not overwrite previous values.
Note: This setting is only applicable when SSLProvider is set to Internal.
Note: For server components (e.g. TCPServer) this is a per-connection setting accessed by passing the ConnectionId. For example:
server.Config("SSLNegotiatedCipher[connId]");
Note: For server components (e.g.TCPServer) this is a per-connection setting accessed by passing the ConnectionId. For example:
server.Config("SSLNegotiatedCipherStrength[connId]");
Note: For server components (e.g. TCPServer) this is a per-connection setting accessed by passing the ConnectionId. For example:
server.Config("SSLNegotiatedCipherSuite[connId]");
Note: For server components (e.g. TCPServer) this is a per-connection setting accessed by passing the ConnectionId. For example:
server.Config("SSLNegotiatedKeyExchange[connId]");
Note: For server components (e.g. TCPServer) this is a per-connection setting accessed by passing the ConnectionId. For example:
server.Config("SSLNegotiatedKeyExchangeStrength[connId]");
Note: For server components (e.g. TCPServer) this is a per-connection setting accessed by passing the ConnectionId. For example:
server.Config("SSLNegotiatedVersion[connId]");
0x00000001 | Ignore time validity status of certificate. |
0x00000002 | Ignore time validity status of CTL. |
0x00000004 | Ignore non-nested certificate times. |
0x00000010 | Allow unknown Certificate Authority. |
0x00000020 | Ignore wrong certificate usage. |
0x00000100 | Ignore unknown certificate revocation status. |
0x00000200 | Ignore unknown CTL signer revocation status. |
0x00000400 | Ignore unknown Certificate Authority revocation status. |
0x00000800 | Ignore unknown Root revocation status. |
0x00008000 | Allow test Root certificate. |
0x00004000 | Trust test Root certificate. |
0x80000000 | Ignore non-matching CN (certificate CN not-matching server name). |
This functionality is currently not available when the provider is OpenSSL.
The value of this setting is a newline (CrLf) separated list of certificates. For instance:
-----BEGIN CERTIFICATE----- MIIEKzCCAxOgAwIBAgIRANTET4LIkxdH6P+CFIiHvTowDQYJKoZIhvcNAQELBQAw ... eWHV5OW1K53o/atv59sOiW5K3crjFhsBOd5Q+cJJnU+SWinPKtANXMht+EDvYY2w F0I1XhM+pKj7FjDr+XNj -----END CERTIFICATE----- \r \n -----BEGIN CERTIFICATE----- MIIEFjCCAv6gAwIBAgIQetu1SMxpnENAnnOz1P+PtTANBgkqhkiG9w0BAQUFADBp .. d8q23djXZbVYiIfE9ebr4g3152BlVCHZ2GyPdjhIuLeH21VbT/dyEHHA -----END CERTIFICATE-----
When specified the class will verify that the server certificate signature algorithm is among the values specified in this setting. If the server certificate signature algorithm is unsupported the class fails with an error.
The format of this value is a comma separated list of hash-signature combinations. For instance:
component.SSLProvider = TCPClientSSLProviders.sslpInternal;
component.Config("SSLEnabledProtocols=3072"); //TLS 1.2
component.Config("TLS12SignatureAlgorithms=sha256-rsa,sha256-dsa,sha1-rsa,sha1-dsa");
The default value for this setting is sha512-ecdsa,sha512-rsa,sha512-dsa,sha384-ecdsa,sha384-rsa,sha384-dsa,sha256-ecdsa,sha256-rsa,sha256-dsa,sha224-ecdsa,sha224-rsa,sha224-dsa,sha1-ecdsa,sha1-rsa,sha1-dsa.
In order to not restrict the server's certificate signature algorithm, specify an empty string as the value for this setting, which will cause the signature_algorithms TLS 1.2 extension to not be sent.
The default value is ecdhe_secp256r1,ecdhe_secp384r1,ecdhe_secp521r1.
When using TLS 1.2 and SSLProvider is set to Internal, the values refer to the supported groups for ECC. The following values are supported:
- "ecdhe_secp256r1" (default)
- "ecdhe_secp384r1" (default)
- "ecdhe_secp521r1" (default)
The default value is set to balance common supported groups and the computational resources required to generate key shares. As a result only some groups are included by default in this setting.
Note: All supported groups can always be used during the handshake even if not listed here, but if a group is used which is not present in this list it will incur an additional round trip and time to generate the key share for that group.
In most cases this setting does not need to be modified. This should only be modified if there is a specific reason to do so.
The default value is ecdhe_x25519,ecdhe_secp256r1,ecdhe_secp384r1,ffdhe_2048,ffdhe_3072
The values are ordered from most preferred to least preferred. The following values are supported:
- "ecdhe_x25519" (default)
- "ecdhe_x448"
- "ecdhe_secp256r1" (default)
- "ecdhe_secp384r1" (default)
- "ecdhe_secp521r1"
- "ffdhe_2048" (default)
- "ffdhe_3072" (default)
- "ffdhe_4096"
- "ffdhe_6144"
- "ffdhe_8192"
- "ed25519" (default)
- "ed448" (default)
- "ecdsa_secp256r1_sha256" (default)
- "ecdsa_secp384r1_sha384" (default)
- "ecdsa_secp521r1_sha512" (default)
- "rsa_pkcs1_sha256" (default)
- "rsa_pkcs1_sha384" (default)
- "rsa_pkcs1_sha512" (default)
- "rsa_pss_sha256" (default)
- "rsa_pss_sha384" (default)
- "rsa_pss_sha512" (default)
The default value is ecdhe_x25519,ecdhe_x448,ecdhe_secp256r1,ecdhe_secp384r1,ecdhe_secp521r1,ffdhe_2048,ffdhe_3072,ffdhe_4096,ffdhe_6144,ffdhe_8192
The values are ordered from most preferred to least preferred. The following values are supported:
- "ecdhe_x25519" (default)
- "ecdhe_x448" (default)
- "ecdhe_secp256r1" (default)
- "ecdhe_secp384r1" (default)
- "ecdhe_secp521r1" (default)
- "ffdhe_2048" (default)
- "ffdhe_3072" (default)
- "ffdhe_4096" (default)
- "ffdhe_6144" (default)
- "ffdhe_8192" (default)
Socket Config Settings
Note: This option is not valid for UDP ports.
Some TCP/IP implementations do not support variable buffer sizes. If that is the case, when the class is activated the InBufferSize reverts to its defined size. The same happens if you attempt to make it too large or too small.
Some TCP/IP implementations do not support variable buffer sizes. If that is the case, when the class is activated the OutBufferSize reverts to its defined size. The same happens if you attempt to make it too large or too small.
Base Config Settings
The following is a list of valid code page identifiers:
Identifier | Name |
037 | IBM EBCDIC - U.S./Canada |
437 | OEM - United States |
500 | IBM EBCDIC - International |
708 | Arabic - ASMO 708 |
709 | Arabic - ASMO 449+, BCON V4 |
710 | Arabic - Transparent Arabic |
720 | Arabic - Transparent ASMO |
737 | OEM - Greek (formerly 437G) |
775 | OEM - Baltic |
850 | OEM - Multilingual Latin I |
852 | OEM - Latin II |
855 | OEM - Cyrillic (primarily Russian) |
857 | OEM - Turkish |
858 | OEM - Multilingual Latin I + Euro symbol |
860 | OEM - Portuguese |
861 | OEM - Icelandic |
862 | OEM - Hebrew |
863 | OEM - Canadian-French |
864 | OEM - Arabic |
865 | OEM - Nordic |
866 | OEM - Russian |
869 | OEM - Modern Greek |
870 | IBM EBCDIC - Multilingual/ROECE (Latin-2) |
874 | ANSI/OEM - Thai (same as 28605, ISO 8859-15) |
875 | IBM EBCDIC - Modern Greek |
932 | ANSI/OEM - Japanese, Shift-JIS |
936 | ANSI/OEM - Simplified Chinese (PRC, Singapore) |
949 | ANSI/OEM - Korean (Unified Hangul Code) |
950 | ANSI/OEM - Traditional Chinese (Taiwan; Hong Kong SAR, PRC) |
1026 | IBM EBCDIC - Turkish (Latin-5) |
1047 | IBM EBCDIC - Latin 1/Open System |
1140 | IBM EBCDIC - U.S./Canada (037 + Euro symbol) |
1141 | IBM EBCDIC - Germany (20273 + Euro symbol) |
1142 | IBM EBCDIC - Denmark/Norway (20277 + Euro symbol) |
1143 | IBM EBCDIC - Finland/Sweden (20278 + Euro symbol) |
1144 | IBM EBCDIC - Italy (20280 + Euro symbol) |
1145 | IBM EBCDIC - Latin America/Spain (20284 + Euro symbol) |
1146 | IBM EBCDIC - United Kingdom (20285 + Euro symbol) |
1147 | IBM EBCDIC - France (20297 + Euro symbol) |
1148 | IBM EBCDIC - International (500 + Euro symbol) |
1149 | IBM EBCDIC - Icelandic (20871 + Euro symbol) |
1200 | Unicode UCS-2 Little-Endian (BMP of ISO 10646) |
1201 | Unicode UCS-2 Big-Endian |
1250 | ANSI - Central European |
1251 | ANSI - Cyrillic |
1252 | ANSI - Latin I |
1253 | ANSI - Greek |
1254 | ANSI - Turkish |
1255 | ANSI - Hebrew |
1256 | ANSI - Arabic |
1257 | ANSI - Baltic |
1258 | ANSI/OEM - Vietnamese |
1361 | Korean (Johab) |
10000 | MAC - Roman |
10001 | MAC - Japanese |
10002 | MAC - Traditional Chinese (Big5) |
10003 | MAC - Korean |
10004 | MAC - Arabic |
10005 | MAC - Hebrew |
10006 | MAC - Greek I |
10007 | MAC - Cyrillic |
10008 | MAC - Simplified Chinese (GB 2312) |
10010 | MAC - Romania |
10017 | MAC - Ukraine |
10021 | MAC - Thai |
10029 | MAC - Latin II |
10079 | MAC - Icelandic |
10081 | MAC - Turkish |
10082 | MAC - Croatia |
12000 | Unicode UCS-4 Little-Endian |
12001 | Unicode UCS-4 Big-Endian |
20000 | CNS - Taiwan |
20001 | TCA - Taiwan |
20002 | Eten - Taiwan |
20003 | IBM5550 - Taiwan |
20004 | TeleText - Taiwan |
20005 | Wang - Taiwan |
20105 | IA5 IRV International Alphabet No. 5 (7-bit) |
20106 | IA5 German (7-bit) |
20107 | IA5 Swedish (7-bit) |
20108 | IA5 Norwegian (7-bit) |
20127 | US-ASCII (7-bit) |
20261 | T.61 |
20269 | ISO 6937 Non-Spacing Accent |
20273 | IBM EBCDIC - Germany |
20277 | IBM EBCDIC - Denmark/Norway |
20278 | IBM EBCDIC - Finland/Sweden |
20280 | IBM EBCDIC - Italy |
20284 | IBM EBCDIC - Latin America/Spain |
20285 | IBM EBCDIC - United Kingdom |
20290 | IBM EBCDIC - Japanese Katakana Extended |
20297 | IBM EBCDIC - France |
20420 | IBM EBCDIC - Arabic |
20423 | IBM EBCDIC - Greek |
20424 | IBM EBCDIC - Hebrew |
20833 | IBM EBCDIC - Korean Extended |
20838 | IBM EBCDIC - Thai |
20866 | Russian - KOI8-R |
20871 | IBM EBCDIC - Icelandic |
20880 | IBM EBCDIC - Cyrillic (Russian) |
20905 | IBM EBCDIC - Turkish |
20924 | IBM EBCDIC - Latin-1/Open System (1047 + Euro symbol) |
20932 | JIS X 0208-1990 & 0121-1990 |
20936 | Simplified Chinese (GB2312) |
21025 | IBM EBCDIC - Cyrillic (Serbian, Bulgarian) |
21027 | Extended Alpha Lowercase |
21866 | Ukrainian (KOI8-U) |
28591 | ISO 8859-1 Latin I |
28592 | ISO 8859-2 Central Europe |
28593 | ISO 8859-3 Latin 3 |
28594 | ISO 8859-4 Baltic |
28595 | ISO 8859-5 Cyrillic |
28596 | ISO 8859-6 Arabic |
28597 | ISO 8859-7 Greek |
28598 | ISO 8859-8 Hebrew |
28599 | ISO 8859-9 Latin 5 |
28605 | ISO 8859-15 Latin 9 |
29001 | Europa 3 |
38598 | ISO 8859-8 Hebrew |
50220 | ISO 2022 Japanese with no halfwidth Katakana |
50221 | ISO 2022 Japanese with halfwidth Katakana |
50222 | ISO 2022 Japanese JIS X 0201-1989 |
50225 | ISO 2022 Korean |
50227 | ISO 2022 Simplified Chinese |
50229 | ISO 2022 Traditional Chinese |
50930 | Japanese (Katakana) Extended |
50931 | US/Canada and Japanese |
50933 | Korean Extended and Korean |
50935 | Simplified Chinese Extended and Simplified Chinese |
50936 | Simplified Chinese |
50937 | US/Canada and Traditional Chinese |
50939 | Japanese (Latin) Extended and Japanese |
51932 | EUC - Japanese |
51936 | EUC - Simplified Chinese |
51949 | EUC - Korean |
51950 | EUC - Traditional Chinese |
52936 | HZ-GB2312 Simplified Chinese |
54936 | Windows XP: GB18030 Simplified Chinese (4 Byte) |
57002 | ISCII Devanagari |
57003 | ISCII Bengali |
57004 | ISCII Tamil |
57005 | ISCII Telugu |
57006 | ISCII Assamese |
57007 | ISCII Oriya |
57008 | ISCII Kannada |
57009 | ISCII Malayalam |
57010 | ISCII Gujarati |
57011 | ISCII Punjabi |
65000 | Unicode UTF-7 |
65001 | Unicode UTF-8 |
Identifier | Name |
1 | ASCII |
2 | NEXTSTEP |
3 | JapaneseEUC |
4 | UTF8 |
5 | ISOLatin1 |
6 | Symbol |
7 | NonLossyASCII |
8 | ShiftJIS |
9 | ISOLatin2 |
10 | Unicode |
11 | WindowsCP1251 |
12 | WindowsCP1252 |
13 | WindowsCP1253 |
14 | WindowsCP1254 |
15 | WindowsCP1250 |
21 | ISO2022JP |
30 | MacOSRoman |
10 | UTF16String |
0x90000100 | UTF16BigEndian |
0x94000100 | UTF16LittleEndian |
0x8c000100 | UTF32String |
0x98000100 | UTF32BigEndian |
0x9c000100 | UTF32LittleEndian |
65536 | Proprietary |
- Product: The product the license is for.
- Product Key: The key the license was generated from.
- License Source: Where the license was found (e.g., RuntimeLicense, License File).
- License Type: The type of license installed (e.g., Royalty Free, Single Server).
- Last Valid Build: The last valid build number for which the license will work.
This setting only works on these classes: AS3Receiver, AS3Sender, Atom, Client(3DS), FTP, FTPServer, IMAP, OFTPClient, SSHClient, SCP, Server(3DS), Sexec, SFTP, SFTPServer, SSHServer, TCPClient, TCPServer.
Setting this configuration setting to true tells the class to use the internal implementation instead of using the system security libraries.
On Windows, this setting is set to false by default. On Linux/macOS, this setting is set to true by default.
To use the system security libraries for Linux, OpenSSL support must be enabled. For more information on how to enable OpenSSL, please refer to the OpenSSL Notes section.
Trappable Errors (MQTT Class)
MQTT Errors
500 MQTT protocol error. Refer to the error message for more information. | |
501 Packet Id pool exhausted, no more packet Ids are available. | |
502 Invalid topic name. Refer to the error message for more information. | |
503 Invalid topic filter. Refer to the error message for more information. | |
504 Message data is malformed. | |
505 Invalid QoS value. Refer to the error message for more information. |
WebSocket Errors
4001 Error transmitting packet. | |
4002 Error sending CLOSE packet. | |
4003 General protocol error. |
HTTP Errors
118 Firewall Error. Error description contains detailed message. | |
143 Busy executing current method. | |
151 HTTP protocol error. The error message has the server response. | |
152 No server specified in URL | |
153 Specified URLScheme is invalid. | |
155 Range operation is not supported by server. | |
156 Invalid cookie index (out of range). | |
301 Interrupted. | |
302 Can't open AttachedFile. |
The class may also return one of the following error codes, which are inherited from other classes.
TCPClient Errors
100 You cannot change the RemotePort at this time. A connection is in progress. | |
101 You cannot change the RemoteHost (Server) at this time. A connection is in progress. | |
102 The RemoteHost address is invalid (0.0.0.0). | |
104 Already connected. If you want to reconnect, close the current connection first. | |
106 You cannot change the LocalPort at this time. A connection is in progress. | |
107 You cannot change the LocalHost at this time. A connection is in progress. | |
112 You cannot change MaxLineLength at this time. A connection is in progress. | |
116 RemotePort cannot be zero. Please specify a valid service port number. | |
117 You cannot change the UseConnection option while the class is active. | |
135 Operation would block. | |
201 Timeout. | |
211 Action impossible in control's present state. | |
212 Action impossible while not connected. | |
213 Action impossible while listening. | |
301 Timeout. | |
302 Could not open file. | |
434 Unable to convert string to selected CodePage. | |
1105 Already connecting. If you want to reconnect, close the current connection first. | |
1117 You need to connect first. | |
1119 You cannot change the LocalHost at this time. A connection is in progress. | |
1120 Connection dropped by remote host. |
SSL Errors
270 Cannot load specified security library. | |
271 Cannot open certificate store. | |
272 Cannot find specified certificate. | |
273 Cannot acquire security credentials. | |
274 Cannot find certificate chain. | |
275 Cannot verify certificate chain. | |
276 Error during handshake. | |
280 Error verifying certificate. | |
281 Could not find client certificate. | |
282 Could not find server certificate. | |
283 Error encrypting data. | |
284 Error decrypting data. |
TCP/IP Errors
10004 [10004] Interrupted system call. | |
10009 [10009] Bad file number. | |
10013 [10013] Access denied. | |
10014 [10014] Bad address. | |
10022 [10022] Invalid argument. | |
10024 [10024] Too many open files. | |
10035 [10035] Operation would block. | |
10036 [10036] Operation now in progress. | |
10037 [10037] Operation already in progress. | |
10038 [10038] Socket operation on non-socket. | |
10039 [10039] Destination address required. | |
10040 [10040] Message too long. | |
10041 [10041] Protocol wrong type for socket. | |
10042 [10042] Bad protocol option. | |
10043 [10043] Protocol not supported. | |
10044 [10044] Socket type not supported. | |
10045 [10045] Operation not supported on socket. | |
10046 [10046] Protocol family not supported. | |
10047 [10047] Address family not supported by protocol family. | |
10048 [10048] Address already in use. | |
10049 [10049] Can't assign requested address. | |
10050 [10050] Network is down. | |
10051 [10051] Network is unreachable. | |
10052 [10052] Net dropped connection or reset. | |
10053 [10053] Software caused connection abort. | |
10054 [10054] Connection reset by peer. | |
10055 [10055] No buffer space available. | |
10056 [10056] Socket is already connected. | |
10057 [10057] Socket is not connected. | |
10058 [10058] Can't send after socket shutdown. | |
10059 [10059] Too many references, can't splice. | |
10060 [10060] Connection timed out. | |
10061 [10061] Connection refused. | |
10062 [10062] Too many levels of symbolic links. | |
10063 [10063] File name too long. | |
10064 [10064] Host is down. | |
10065 [10065] No route to host. | |
10066 [10066] Directory not empty | |
10067 [10067] Too many processes. | |
10068 [10068] Too many users. | |
10069 [10069] Disc Quota Exceeded. | |
10070 [10070] Stale NFS file handle. | |
10071 [10071] Too many levels of remote in path. | |
10091 [10091] Network subsystem is unavailable. | |
10092 [10092] WINSOCK DLL Version out of range. | |
10093 [10093] Winsock not loaded yet. | |
11001 [11001] Host not found. | |
11002 [11002] Non-authoritative 'Host not found' (try again or check DNS setup). | |
11003 [11003] Non-recoverable errors: FORMERR, REFUSED, NOTIMP. | |
11004 [11004] Valid name, no data record (check DNS setup). |