Struct ipworksiot::MQTTBroker

Properties   Methods   Events   Config Settings   Errors  

A lightweight, fully-featured MQTT broker implementation.

Syntax

ipworksiot::MQTTBroker

Remarks

The MQTTBroker struct provides a lightweight, fully-featured MQTT broker implementation with support for version 3.1.1. The struct supports plaintext and TLS-enabled connections over both standard TCP and WebSockets.

Configuring Listeners

The struct supports the following protocols:

Multiple protocols can be enabled (each on a different port): // Plaintext TCP mqttbroker.AddBrokerListener("127.0.0.1", PLAIN_PORT, (int)MQTTBrokerProtocols.mbpTCP, 0, null, null, null); // TCP with TLS mqttbroker.AddBrokerListener("127.0.0.1", SSL_PORT, (int)MQTTBrokerProtocols.mbpTLS, (int)CertStoreTypes.cstPFXFile, "test1.pfx", "test", "*"); // Plaintext WebSocket mqttbroker.AddBrokerListener("127.0.0.1", WS_PORT, (int)MQTTBrokerProtocols.mbpWS, 0, null, null, null); // WebSocket with TLS mqttbroker.AddBrokerListener("127.0.0.1", WSS_PORT, (int)MQTTBrokerProtocols.mbpWSS, (int)CertStoreTypes.cstPFXFile, "test2.pfx", "test", "*"); Once all listeners have been added, the broker can be started via the start_listening method.

Handling Sessions

broker.OnSessionRequest += (s,e) => { // Check e.UserName and e.Password if needed // Set Accept to true to accept the session request e.Accept = true; };

Handling Subscriptions

The ClientId is used to identify this client in subsequent actions.

The TopicFilter is the requested topic the client wishes to subscribe to.

The RequestedQoS is the client's preferred QoS level.

ReturnCode is used to confirm the maximum QoS level granted for this subscription or indicate a failure. This can be less than the client's RequestedQoS.

Incoming Messages

The on_message_receiving event fires when a message is initially received and contains message metadata.

The on_incoming_message_status event fires each time an incoming message's state is updated.

• MessageId: A unique identifier for this message.
• DUP: Whether or not the server has indicated that this message is a duplicate of another message received previously.
• QoS: The message's QoS level.
• Retain: Whether or not this message was received as a result of subscribing to a topic.
• PacketId: The message packet Id. This will always be -1 if QoS is 0.
• State: Information about the incoming message's state.
  • 6 - For an incoming QoS 1 message, which has been received from the client, but prior to sending the PUBACK for it. When the PUBACK is sent, the state will change to 10.
  • 7 - For an incoming QoS 2 message, which has been received from a client, but prior to sending the PUBREC for it,
  • 8 - For an incoming QoS 2 message, which has sent the PUBREC, but waiting to receive the PUBREL for it.
  • 9 - For an incoming QoS 2 message, which has received the PUBREL, but prior to sending the PUBCOMP for it. When the PUBCOMP is sent, the state will change to 10.
  • 10 - Message successfully received.

Outgoing Messages

The on_message_sending event fires when a message is initially sent to a client and contains message metadata.

The on_outgoing_message_status event fires each time an outgoing message's state is updated.

• MessageId: A unique identifier for this message.
• DUP: Whether or not the server has indicated that this message is a duplicate of another message sent previously.
• QoS: The message's QoS level.
• Retain: Whether or not this message is a retained message.
• PacketId: The message packet Id. This will always be -1 if QoS is 0.
• State: Information about the outgoing message's state.
  • 1 - Outgoing message is waiting to be sent
  • 2 - For an outgoing QoS 1 message, which has been sent to the client and waiting for the PUBACK. When the PUBACK is received, the state will change to 10.
  • 3 - For an outgoing QoS 2 message, which has been sent to the client and waiting for the PUBREC.
  • 4 - For an outgoing QoS 2 message, which has received the PUBREC, prior to sending the PUBREL for it.
  • 5 - For an outgoing QoS 2 message, which has sent the PUBREL. When the PUBCOMP is received, the state will change to 10.
  • 10 - Message successfully sent.

Saving and Loading Sessions

save_session returns a JSON string representing the client's subscriptions and messages. This can later be loaded via load_session to restore the client's state.

The format should be a JSON string with the following parameters: string sessiondata = broker.SaveSession("Client1"); // sessiondata may contain a JSON string with information like this: { "ClientId":"Client1", "Subscriptions":[{ // A collection of the client's subscribed topics "Topic":"topic name", "QoS":2, }], "IncomingMessages": [{ // A collection of incoming messages "MessageId":1, // The incoming message's ID "Topic":"A", // The incoming message's topic "Payload":"54657374", // hexadecimal message payload "QoS":2, // The incoming message's QoS level "DUP":false, // Whether this message is a duplicate "Retain":false, // Whether this is a retained message "PacketId":1, // This message's packet ID "State":3 // See IncomingMessageStatus event for State details }], "OutgoingMessages":[{ // A collection of outgoing messages "MessageId":2, "Topic":"A", "Payload":"54657374", "QoS":2, "DUP":false, "Retain":false, "PacketId":2, "State":3 // See OutgoingMessageStatus event for State details }] } // Later, the LoadSession method can be used to load the session data broker.LoadSession(sessiondata);

Object Lifetime

The new() method returns a mutable reference to a struct instance. The object itself is kept in the global list maintained by IPWorksIoT. Due to this, the MQTTBroker struct cannot be disposed of automatically. Please, call the dispose(&mut self) method of MQTTBroker when you have finished using the instance.

Property List

The following is the full list of the properties of the struct with short descriptions. Click on the links for further details.

Method List

The following is the full list of the methods of the struct with short descriptions. Click on the links for further details.

Event List

The following is the full list of the events fired by the struct with short descriptions. Click on the links for further details.

Config Settings

The following is a list of config settings for the struct with short descriptions. Click on the links for further details.

connection_count property (MQTTBroker Struct)

The number of records in the Connection arrays.

Syntax

fn connection_count(&self ) -> Result<i32, IPWorksIoTError> 

Default Value

0

Remarks

This property controls the size of the following arrays:

• connection_client_id
• connection_id
• connection_keep_alive
• connection_local_host
• connection_local_port
• connection_protocol
• connection_remote_host
• connection_remote_port
• connection_user_name

The array indices start at 0 and end at connection_count - 1.

This property is read-only.

Data Type

i32

connection_client_id property (MQTTBroker Struct)

A unique identifier for the client.

Syntax

fn connection_client_id(&self , ConnectionId : i32) -> Result<String, IPWorksIoTError> 

Default Value

""

Remarks

A unique identifier for the client.

The ConnectionId parameter specifies the index of the item in the array. The size of the array is controlled by the ConnectionCount property.

This property is read-only.

Data Type

String

connection_id property (MQTTBroker Struct)

This property contains an identifier generated by the struct to identify each connection.

Syntax

fn connection_id(&self , ConnectionId : i32) -> Result<i32, IPWorksIoTError> 

Default Value

0

Remarks

This field contains an identifier generated by the component to identify each connection. This identifier is unique to this connection.

The ConnectionId parameter specifies the index of the item in the array. The size of the array is controlled by the ConnectionCount property.

This property is read-only.

Data Type

i32

connection_keep_alive property (MQTTBroker Struct)

When set to 1, KEEPALIVE packets are enabled (for long connections).

Syntax

fn connection_keep_alive(&self , ConnectionId : i32) -> Result<i32, IPWorksIoTError> 

Default Value

0

Remarks

When set to 1, KEEPALIVE packets are enabled (for long connections).

This property enables the SO_KEEPALIVE option on the incoming connections. This option prevents long connections from timing out in case of inactivity.

NOTE: System Transmission Control Protocol (TCP)/IP stack implementations are not required to support SO_KEEPALIVE.

This property is shared among incoming connections. When the property is set, the corresponding value is set for incoming connections as they are accepted. Existing connections are not modified.

The ConnectionId parameter specifies the index of the item in the array. The size of the array is controlled by the ConnectionCount property.

This property is read-only.

Data Type

i32

connection_local_host property (MQTTBroker Struct)

This property shows the IP address of the interface through which the connection is passing.

Syntax

fn connection_local_host(&self , ConnectionId : i32) -> Result<String, IPWorksIoTError> 

Default Value

""

Remarks

This field shows the IP address of the interface through which the connection is passing.

LocalAddress is important for multihomed hosts so that it can be used to find the particular network interface through which an individual connection is going.

The ConnectionId parameter specifies the index of the item in the array. The size of the array is controlled by the ConnectionCount property.

This property is read-only.

Data Type

String

connection_local_port property (MQTTBroker Struct)

This property shows the Transmission Control Protocol (TCP) port on the local host through which the connection is passing.

Syntax

fn connection_local_port(&self , ConnectionId : i32) -> Result<i32, IPWorksIoTError> 

Default Value

0

Remarks

This field shows the Transmission Control Protocol (TCP) port on the local host through which the connection is passing.

The ConnectionId parameter specifies the index of the item in the array. The size of the array is controlled by the ConnectionCount property.

This property is read-only.

Data Type

i32

connection_protocol property (MQTTBroker Struct)

The protocol of the connected client.

Syntax

fn connection_protocol(&self , ConnectionId : i32) -> Result<i32, IPWorksIoTError> 

Possible Values

0   // TCP
1   // TLS
2   // WS
3   // WSS

Default Value

0

Remarks

The protocol of the connected client.

The struct supports the following protocols:

The ConnectionId parameter specifies the index of the item in the array. The size of the array is controlled by the ConnectionCount property.

This property is read-only.

Data Type

i32

connection_remote_host property (MQTTBroker Struct)

This property shows the IP address of the remote host through which the connection is coming.

Syntax

fn connection_remote_host(&self , ConnectionId : i32) -> Result<String, IPWorksIoTError> 

Default Value

""

Remarks

This field shows the IP address of the remote host through which the connection is coming.

The connection must be valid or an error will be fired.

If the component 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.

The ConnectionId parameter specifies the index of the item in the array. The size of the array is controlled by the ConnectionCount property.

This property is read-only.

Data Type

String

connection_remote_port property (MQTTBroker Struct)

This property shows the Transmission Control Protocol (TCP) port on the remote host through which the connection is coming.

Syntax

fn connection_remote_port(&self , ConnectionId : i32) -> Result<i32, IPWorksIoTError> 

Default Value

0

Remarks

This field shows the Transmission Control Protocol (TCP) port on the remote host through which the connection is coming.

The connection must be valid or an error will be fired.

The ConnectionId parameter specifies the index of the item in the array. The size of the array is controlled by the ConnectionCount property.

This property is read-only.

Data Type

i32

connection_user_name property (MQTTBroker Struct)

The username for this connected client.

Syntax

fn connection_user_name(&self , ConnectionId : i32) -> Result<String, IPWorksIoTError> 

Default Value

""

Remarks

The username for this connected client.

The ConnectionId parameter specifies the index of the item in the array. The size of the array is controlled by the ConnectionCount property.

This property is read-only.

Data Type

String

default_idle_timeout property (MQTTBroker Struct)

This property includes the default idle timeout for inactive clients.

Syntax

fn default_idle_timeout(&self ) -> Result<i32, IPWorksIoTError> 
fn set_default_idle_timeout(&self, value : i32) ->  Option<IPWorksIoTError> 

Default Value

0

Remarks

This property specifies the idle timeout (in seconds) for clients. When set to a positive value, the struct will disconnect idle clients after the specified timeout.

This applies only to clients that have not sent or received data within default_idle_timeout seconds.

If set to 0 (default), no idle timeout is applied.

NOTE: do_events must be called for the struct to check existing connections.

Data Type

i32

listener_count property (MQTTBroker Struct)

The number of records in the Listener arrays.

Syntax

fn listener_count(&self ) -> Result<i32, IPWorksIoTError> 

Default Value

0

Remarks

This property controls the size of the following arrays:

• listener_local_host
• listener_local_port
• listener_protocol
• listener_ssl_authenticate_clients
• listener_ssl_cert_store
• listener_ssl_cert_store_password
• listener_ssl_cert_store_type
• listener_ssl_cert_subject

The array indices start at 0 and end at listener_count - 1.

This property is read-only.

Data Type

i32

listener_local_host property (MQTTBroker Struct)

The name of the local host or user-assigned IP interface through which connections are initiated or accepted.

Syntax

fn listener_local_host(&self , ListenerIndex : i32) -> Result<String, IPWorksIoTError> 

Default Value

""

Remarks

The name of the local host or user-assigned IP interface through which connections are initiated or accepted.

The ListenerIndex parameter specifies the index of the item in the array. The size of the array is controlled by the ListenerCount property.

This property is read-only.

Data Type

String

listener_local_port property (MQTTBroker Struct)

This property includes the port in the local host for this listener.

Syntax

fn listener_local_port(&self , ListenerIndex : i32) -> Result<i32, IPWorksIoTError> 

Default Value

0

Remarks

This field includes the port in the local host for this listener.

The ListenerIndex parameter specifies the index of the item in the array. The size of the array is controlled by the ListenerCount property.

This property is read-only.

Data Type

i32

listener_protocol property (MQTTBroker Struct)

The struct supports the following protocols: 0 (mbpTCP) Plaintext TCP 1 (mbpTLS) SSL/TLS over TCP 2 (mbpWS) Plaintext WebSocket 3 (mbpWSS) SSL/TLS over WebSocket .

Syntax

fn listener_protocol(&self , ListenerIndex : i32) -> Result<i32, IPWorksIoTError> 

Possible Values

0   // TCP
1   // TLS
2   // WS
3   // WSS

Default Value

0

Remarks

The struct supports the following protocols:

The ListenerIndex parameter specifies the index of the item in the array. The size of the array is controlled by the ListenerCount property.

This property is read-only.

Data Type

i32

listener_ssl_authenticate_clients property (MQTTBroker Struct)

If set to True, the server asks the client(s) for a certificate.

Syntax

fn listener_ssl_authenticate_clients(&self , ListenerIndex : i32) -> Result<bool, IPWorksIoTError> 

Default Value

false

Remarks

If set to True, the server asks the client(s) for a certificate.

This is used in conjunction with the on_ssl_client_authentication event. Please refer to the documentation of the on_ssl_client_authentication event for details.

The ListenerIndex parameter specifies the index of the item in the array. The size of the array is controlled by the ListenerCount property.

This property is read-only.

Data Type

bool

listener_ssl_cert_store property (MQTTBroker Struct)

The name of the certificate store for the listener's certificate.

Syntax

fn listener_ssl_cert_store(&self , ListenerIndex : i32) -> Result<Vec<u8>, IPWorksIoTError> 

Default Value

"MY"

Remarks

The name of the certificate store for the listener's certificate.

The listener_store_type property denotes the type of the certificate store specified by listener_store. If the store is password-protected, specify the password in listener_store_password.

listener_store is used in conjunction with the listener_subject property to specify client certificates. If listener_store has a value, and listener_subject or listener_encoded is set, a search for a certificate is initiated. Please see the listener_subject property for details.

Designations of certificate stores are platform dependent.

The following designations are the most common User and Machine certificate stores in Windows:

When the certificate store type is cstPFXFile, this property must be set to the name of the file. When the type is cstPFXBlob, the property must be set to the binary contents of a PFX file (i.e., PKCS#12 certificate store).

The ListenerIndex parameter specifies the index of the item in the array. The size of the array is controlled by the ListenerCount property.

This property is read-only.

Data Type

Vec

listener_ssl_cert_store_password property (MQTTBroker Struct)

This is the password of the SSL certificate.

Syntax

fn listener_ssl_cert_store_password(&self , ListenerIndex : i32) -> Result<String, IPWorksIoTError> 

Default Value

""

Remarks

This is the password of the SSL certificate.

The ListenerIndex parameter specifies the index of the item in the array. The size of the array is controlled by the ListenerCount property.

This property is read-only.

Data Type

String

listener_ssl_cert_store_type property (MQTTBroker Struct)

This is the type of certificate store for this certificate.

Syntax

fn listener_ssl_cert_store_type(&self , ListenerIndex : i32) -> Result<i32, IPWorksIoTError> 

Possible Values

0   // User
1   // Machine
2   // PFXFile
3   // PFXBlob
4   // JKSFile
5   // JKSBlob
6   // PEMKeyFile
7   // PEMKeyBlob
8   // PublicKeyFile
9   // PublicKeyBlob
10   // SSHPublicKeyBlob
11   // P7BFile
12   // P7BBlob
13   // SSHPublicKeyFile
14   // PPKFile
15   // PPKBlob
16   // XMLFile
17   // XMLBlob
18   // JWKFile
19   // JWKBlob
20   // SecurityKey
21   // BCFKSFile
22   // BCFKSBlob
23   // PKCS11
99   // Auto

Default Value

0

Remarks

This is the type of certificate store for this certificate.

Designations of certificate stores are platform dependent.

The following designations are the most common User and Machine certificate stores in Windows:

When the certificate store type is cstPFXFile, this property must be set to the name of the file. When the type is cstPFXBlob, the property must be set to the binary contents of a PFX file (i.e., PKCS#12 certificate store).

The ListenerIndex parameter specifies the index of the item in the array. The size of the array is controlled by the ListenerCount property.

This property is read-only.

Data Type

i32

listener_ssl_cert_subject property (MQTTBroker Struct)

The subject of the SSL certificate.

Syntax

fn listener_ssl_cert_subject(&self , ListenerIndex : i32) -> Result<String, IPWorksIoTError> 

Default Value

""

Remarks

The subject of the SSL certificate.

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=example@email.com". Common fields and their meanings are as follows:

If a field value contains a comma, it must be quoted.

The ListenerIndex parameter specifies the index of the item in the array. The size of the array is controlled by the ListenerCount property.

This property is read-only.

Data Type

String

listening property (MQTTBroker Struct)

This property indicates whether the struct is listening for incoming connections on LocalPort.

Syntax

fn listening(&self ) -> Result<bool, IPWorksIoTError> 

Default Value

false

Remarks

This property indicates whether the struct is listening for connections on the port specified by the local_port property. Use the start_listening and stop_listening methods to control whether the struct is listening.

This property is read-only.

Data Type

bool

message_count property (MQTTBroker Struct)

The number of records in the Message arrays.

Syntax

fn message_count(&self ) -> Result<i32, IPWorksIoTError> 

Default Value

0

Remarks

This property controls the size of the following arrays:

• message_id
• message_payload
• message_topic

The array indices start at 0 and end at message_count - 1.

This property is read-only.

Data Type

i32

message_id property (MQTTBroker Struct)

Message identifier used to associate the message state.

Syntax

fn message_id(&self , MessageIndex : i32) -> Result<i64, IPWorksIoTError> 

Default Value

0

Remarks

Message identifier used to associate the message state.

The MessageIndex parameter specifies the index of the item in the array. The size of the array is controlled by the MessageCount property.

This property is read-only.

Data Type

i64

message_payload property (MQTTBroker Struct)

This message's raw data payload.

Syntax

fn message_payload(&self , MessageIndex : i32) -> Result<Vec<u8>, IPWorksIoTError> 

Default Value

""

Remarks

This message's raw data payload.

The MessageIndex parameter specifies the index of the item in the array. The size of the array is controlled by the MessageCount property.

This property is read-only.

Data Type

Vec

message_topic property (MQTTBroker Struct)

This message's topic.

Syntax

fn message_topic(&self , MessageIndex : i32) -> Result<String, IPWorksIoTError> 

Default Value

""

Remarks

This message's topic.

The MessageIndex parameter specifies the index of the item in the array. The size of the array is controlled by the MessageCount property.

This property is read-only.

Data Type

String

session_count property (MQTTBroker Struct)

The number of records in the Session arrays.

Syntax

fn session_count(&self ) -> Result<i32, IPWorksIoTError> 

Default Value

0

Remarks

This property controls the size of the following arrays:

• session_client_id
• session_incoming_messages
• session_outgoing_messages
• session_sub_granted_qo_s
• session_sub_topic_filters

The array indices start at 0 and end at session_count - 1.

This property is read-only.

Data Type

i32

session_client_id property (MQTTBroker Struct)

A unique identifier for the client.

Syntax

fn session_client_id(&self , SessionIndex : i32) -> Result<String, IPWorksIoTError> 

Default Value

""

Remarks

A unique identifier for the client.

The SessionIndex parameter specifies the index of the item in the array. The size of the array is controlled by the SessionCount property.

This property is read-only.

Data Type

String

session_incoming_messages property (MQTTBroker Struct)

A collection of incoming messages.

Syntax

fn session_incoming_messages(&self , SessionIndex : i32) -> Result<String, IPWorksIoTError> 

Default Value

""

Remarks

A collection of incoming messages.

The SessionIndex parameter specifies the index of the item in the array. The size of the array is controlled by the SessionCount property.

This property is read-only.

Data Type

String

session_outgoing_messages property (MQTTBroker Struct)

A collection of outgoing messages.

Syntax

fn session_outgoing_messages(&self , SessionIndex : i32) -> Result<String, IPWorksIoTError> 

Default Value

""

Remarks

A collection of outgoing messages.

The SessionIndex parameter specifies the index of the item in the array. The size of the array is controlled by the SessionCount property.

This property is read-only.

Data Type

String

session_sub_granted_qo_s property (MQTTBroker Struct)

The subscription's granted QoS level for the client.

Syntax

fn session_sub_granted_qo_s(&self , SessionIndex : i32) -> Result<String, IPWorksIoTError> 

Default Value

""

Remarks

The subscription's granted QoS level for the client.

The SessionIndex parameter specifies the index of the item in the array. The size of the array is controlled by the SessionCount property.

This property is read-only.

Data Type

String

session_sub_topic_filters property (MQTTBroker Struct)

The subscription topic filters for this client session.

Syntax

fn session_sub_topic_filters(&self , SessionIndex : i32) -> Result<String, IPWorksIoTError> 

Default Value

""

Remarks

The subscription topic filters for this client session.

The SessionIndex parameter specifies the index of the item in the array. The size of the array is controlled by the SessionCount property.

This property is read-only.

Data Type

String

ssl_provider property (MQTTBroker Struct)

The Secure Sockets Layer/Transport Layer Security (SSL/TLS) implementation to use.

Syntax

fn ssl_provider(&self ) -> Result<i32, IPWorksIoTError> 
fn set_ssl_provider(&self, value : i32) ->  Option<IPWorksIoTError> 

Possible Values

0   // Automatic
1   // Platform
2   // Internal

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 struct 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 as follows:

In most cases using the default value (Automatic) is recommended. The struct will select a provider depending on the current platform.

When Automatic is selected, on Windows, the struct will use the platform implementation. On Linux/macOS, the struct will use the internal implementation. When TLS 1.3 is enabled via SSLEnabledProtocols, the struct will always try and use the platform implementation. If the platform TLS 1.3 implementation is not available, the internal implementation will be used.

Data Type

i32

add_broker_listener method (MQTTBroker Struct)

Creates a new listener for the broker service.

Syntax

fn add_broker_listener(&self, local_host : &str, local_port : i32, protocol : i32, ssl_cert_store_type : i32, ssl_cert_store : &[u8], ssl_cert_store_password : &str, ssl_cert_subject : &str) -> Result<(), IPWorksIoTError>

Remarks

AddBrokerListener adds a new listener to the listeners collection. Any listeners must be configured before starting the broker. Multiple protocols can be supported by adding different listeners.

The struct supports the following protocols:

Certificate details can be provided via the following parameters:

config method (MQTTBroker Struct)

Sets or retrieves a configuration setting.

Syntax

fn config(&self, configuration_string : &str) ->  Result<String, IPWorksIoTError>

Remarks

config is a generic method available in every struct. It is used to set and retrieve configuration settings for the struct.

These settings are similar in functionality to properties, but they are rarely used. In order to avoid "polluting" the property namespace of the struct, 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.

disconnect method (MQTTBroker Struct)

This method disconnects the specified client.

Syntax

fn disconnect(&self, connection_id : i32) -> Result<(), IPWorksIoTError>

Remarks

Calling this method will disconnect the client specified by the connection_id parameter.

do_events method (MQTTBroker Struct)

This method processes events from the internal message queue.

Syntax

fn do_events(&self) -> Result<(), IPWorksIoTError>

Remarks

When do_events is called, the struct processes any available events. If no events are available, it waits for a preset period of time, and then returns.

interrupt method (MQTTBroker Struct)

This method interrupts a synchronous send to the remote host.

Syntax

fn interrupt(&self, connection_id : i32) -> Result<(), IPWorksIoTError>

Remarks

This property is called using the Connection Id if you wish to interrupt a connection and stop a file from uploading without disconnecting the client connected to the struct. If you use send_file to upload a file, the struct will run synchronously on that Connection Id until it is completed.

load_session method (MQTTBroker Struct)

Restores session data for a specified client, enabling resumption of pending operations or message delivery.

Syntax

fn load_session(&self, session_info : &str) -> Result<(), IPWorksIoTError>

Remarks

The load_session method is used to load prior client session information if required. This can be used after shutting down a broker to preserve session data and ensure messages can be redelivered once the broker is restarted.

The save_session method can be used to save session data, and the resulting string can be provided to the load_session method.

The format should be a JSON string with the following parameters: { "ClientId":"Client1", "Subscriptions":[{ // A collection of the client's subscribed topics "Topic":"topic name", "QoS":2, }], "IncomingMessages": [{ // A collection of incoming messages "MessageId":1, // The incoming message's ID "Topic":"A", // The incoming message's topic "Payload":"54657374", // hexadecimal message payload "QoS":2, // The incoming message's QoS level "DUP":false, // Whether this message is a duplicate "Retain":false, // Whether this is a retained message "PacketId":1, // This message's packet ID "State":3 // See IncomingMessageStatus event for State details }], "OutgoingMessages":[{ // A collection of outgoing messages "MessageId":2, "Topic":"A", "Payload":"54657374", "QoS":2, "DUP":false, "Retain":false, "PacketId":2, "State":3 // See OutgoingMessageStatus event for State details }] } Session data can be saved with save_session, then later loaded with load_session string sessiondata = broker.SaveSession("Client1"); // sessiondata contains session information for Client1 ... broker.LoadSession(sessiondata);

reset method (MQTTBroker Struct)

This method will reset the struct.

Syntax

fn reset(&self) -> Result<(), IPWorksIoTError>

Remarks

This method will reset the struct's properties to their default values.

save_session method (MQTTBroker Struct)

Saves the current state of a client session, including message queues and subscription data, for later retrieval.

Syntax

fn save_session(&self, client_id : &str) ->  Result<String, IPWorksIoTError>

Remarks

Returns a JSON string representing the client's subscriptions and messages. This can later be loaded via load_session to restore the client's state.

The format should be a JSON string with the following parameters: string sessiondata = broker.SaveSession("Client1"); // sessiondata may contain a JSON string with information like this: { "ClientId":"Client1", "Subscriptions":[{ // A collection of the client's subscribed topics "Topic":"topic name", "QoS":2, }], "IncomingMessages": [{ // A collection of incoming messages "MessageId":1, // The incoming message's ID "Topic":"A", // The incoming message's topic "Payload":"54657374", // hexadecimal message payload "QoS":2, // The incoming message's QoS level "DUP":false, // Whether this message is a duplicate "Retain":false, // Whether this is a retained message "PacketId":1, // This message's packet ID "State":3 // See IncomingMessageStatus event for State details }], "OutgoingMessages":[{ // A collection of outgoing messages "MessageId":2, "Topic":"A", "Payload":"54657374", "QoS":2, "DUP":false, "Retain":false, "PacketId":2, "State":3 // See OutgoingMessageStatus event for State details }] }

shutdown method (MQTTBroker Struct)

This method shuts down the server.

Syntax

fn shutdown(&self) -> Result<(), IPWorksIoTError>

Remarks

This method shuts down the server. Calling this method is equivalent to calling stop_listening and then breaking every client connection by calling disconnect.

start_listening method (MQTTBroker Struct)

This method starts listening for incoming connections.

Syntax

fn start_listening(&self) -> Result<(), IPWorksIoTError>

Remarks

This method begins listening for incoming connections on the port specified by local_port. Once listening, events will fire as new clients connect and data are transferred.

To stop listening for new connections, call stop_listening. To stop listening for new connections and to disconnect all existing clients, call shutdown.

stop_listening method (MQTTBroker Struct)

This method stops listening for new connections.

Syntax

fn stop_listening(&self) -> Result<(), IPWorksIoTError>

Remarks

This method stops listening for new connections. After being called, any new connection attempts will be rejected. Calling this method does not disconnect existing connections.

To stop listening and to disconnect all existing clients, call shutdown instead.

on_connected event (MQTTBroker Struct)

This event is fired immediately after a connection completes (or fails).

Syntax

// MQTTBrokerConnectedEventArgs carries the MQTTBroker Connected event's parameters.
pub struct MQTTBrokerConnectedEventArgs {
  fn connection_id(&self) -> i32
  fn status_code(&self) -> i32
  fn description(&self) -> &String
}

// MQTTBrokerConnectedEvent defines the signature of the MQTTBroker Connected event's handler function.
pub trait MQTTBrokerConnectedEvent {
  fn on_connected(&self, sender : MQTTBroker, e : &mut MQTTBrokerConnectedEventArgs);
}

impl <'a> MQTTBroker<'a> {
  pub fn on_connected(&self) -> &'a dyn MQTTBrokerConnectedEvent;
  pub fn set_on_connected(&mut self, value : &'a dyn MQTTBrokerConnectedEvent);
  ...
}

Remarks

If the connection is made normally, status_code is 0, and description is "OK".

If the connection fails, status_code has the error code returned by the system. description contains a description of this code. The value of status_code is equal to the value of the system error.

Please refer to the Error Codes section for more information.

on_connection_request event (MQTTBroker Struct)

This event is fired when a request for connection comes from a remote host.

Syntax

// MQTTBrokerConnectionRequestEventArgs carries the MQTTBroker ConnectionRequest event's parameters.
pub struct MQTTBrokerConnectionRequestEventArgs {
  fn address(&self) -> &String
  fn port(&self) -> i32
  fn accept(&self) -> bool
  fn set_accept(&self, value : bool)
}

// MQTTBrokerConnectionRequestEvent defines the signature of the MQTTBroker ConnectionRequest event's handler function.
pub trait MQTTBrokerConnectionRequestEvent {
  fn on_connection_request(&self, sender : MQTTBroker, e : &mut MQTTBrokerConnectionRequestEventArgs);
}

impl <'a> MQTTBroker<'a> {
  pub fn on_connection_request(&self) -> &'a dyn MQTTBrokerConnectionRequestEvent;
  pub fn set_on_connection_request(&mut self, value : &'a dyn MQTTBrokerConnectionRequestEvent);
  ...
}

Remarks

This event indicates an incoming connection. The connection is accepted by default. address and port will contain information about the remote host requesting the inbound connection. If you want to refuse it, you can set the accept parameter to False.

on_disconnected event (MQTTBroker Struct)

This event is fired when a connection is closed.

Syntax

// MQTTBrokerDisconnectedEventArgs carries the MQTTBroker Disconnected event's parameters.
pub struct MQTTBrokerDisconnectedEventArgs {
  fn connection_id(&self) -> i32
  fn status_code(&self) -> i32
  fn description(&self) -> &String
}

// MQTTBrokerDisconnectedEvent defines the signature of the MQTTBroker Disconnected event's handler function.
pub trait MQTTBrokerDisconnectedEvent {
  fn on_disconnected(&self, sender : MQTTBroker, e : &mut MQTTBrokerDisconnectedEventArgs);
}

impl <'a> MQTTBroker<'a> {
  pub fn on_disconnected(&self) -> &'a dyn MQTTBrokerDisconnectedEvent;
  pub fn set_on_disconnected(&mut self, value : &'a dyn MQTTBrokerDisconnectedEvent);
  ...
}

Remarks

If the connection is broken normally, status_code is 0, and description is "OK".

If the connection is broken for any other reason, status_code has the error code returned by the system. description contains a description of this code. The value of status_code is equal to the value of the system error.

Please refer to the Error Codes section for more information.

on_error event (MQTTBroker Struct)

This event fires information about errors during data delivery.

Syntax

// MQTTBrokerErrorEventArgs carries the MQTTBroker Error event's parameters.
pub struct MQTTBrokerErrorEventArgs {
  fn connection_id(&self) -> i32
  fn error_code(&self) -> i32
  fn description(&self) -> &String
}

// MQTTBrokerErrorEvent defines the signature of the MQTTBroker Error event's handler function.
pub trait MQTTBrokerErrorEvent {
  fn on_error(&self, sender : MQTTBroker, e : &mut MQTTBrokerErrorEventArgs);
}

impl <'a> MQTTBroker<'a> {
  pub fn on_error(&self) -> &'a dyn MQTTBrokerErrorEvent;
  pub fn set_on_error(&mut self, value : &'a dyn MQTTBrokerErrorEvent);
  ...
}

Remarks

The on_error event is fired in case of exceptional conditions during message processing. Normally, the struct fails with an error.

error_code contains an error code and description contains a textual description of the error. For a list of valid error codes and their descriptions, please refer to the Error Codes section.

connection_id indicates the connection for which the error is applicable.

on_incoming_message_status event (MQTTBroker Struct)

Fires when an incoming message's state is updated.

Syntax

// MQTTBrokerIncomingMessageStatusEventArgs carries the MQTTBroker IncomingMessageStatus event's parameters.
pub struct MQTTBrokerIncomingMessageStatusEventArgs {
  fn connection_id(&self) -> i32
  fn client_id(&self) -> &String
  fn message_id(&self) -> i64
  fn dup(&self) -> bool
  fn qo_s(&self) -> i32
  fn retain(&self) -> bool
  fn packet_id(&self) -> i32
  fn state(&self) -> i32
}

// MQTTBrokerIncomingMessageStatusEvent defines the signature of the MQTTBroker IncomingMessageStatus event's handler function.
pub trait MQTTBrokerIncomingMessageStatusEvent {
  fn on_incoming_message_status(&self, sender : MQTTBroker, e : &mut MQTTBrokerIncomingMessageStatusEventArgs);
}

impl <'a> MQTTBroker<'a> {
  pub fn on_incoming_message_status(&self) -> &'a dyn MQTTBrokerIncomingMessageStatusEvent;
  pub fn set_on_incoming_message_status(&mut self, value : &'a dyn MQTTBrokerIncomingMessageStatusEvent);
  ...
}

Remarks

The IncomingMessageStatus event fires each time an incoming message's state is updated.

• MessageId: A unique identifier for this message.
• DUP: Whether or not the server has indicated that this message is a duplicate of another message received previously.
• QoS: The message's QoS level.
• Retain: Whether or not this message was received as a result of subscribing to a topic.
• PacketId: The message packet Id. This will always be -1 if QoS is 0.
• State: Information about the incoming message's state.
  • 6 - For an incoming QoS 1 message, which has been received from the client, but prior to sending the PUBACK for it. When the PUBACK is sent, the state will change to 10.
  • 7 - For an incoming QoS 2 message, which has been received from a client, but prior to sending the PUBREC for it,
  • 8 - For an incoming QoS 2 message, which has sent the PUBREC, but waiting to receive the PUBREL for it.
  • 9 - For an incoming QoS 2 message, which has received the PUBREL, but prior to sending the PUBCOMP for it. When the PUBCOMP is sent, the state will change to 10.
  • 10 - Message successfully received.

on_log event (MQTTBroker Struct)

Fires once for each log message.

Syntax

// MQTTBrokerLogEventArgs carries the MQTTBroker Log event's parameters.
pub struct MQTTBrokerLogEventArgs {
  fn connection_id(&self) -> i32
  fn log_level(&self) -> i32
  fn message(&self) -> &String
  fn log_type(&self) -> &String
}

// MQTTBrokerLogEvent defines the signature of the MQTTBroker Log event's handler function.
pub trait MQTTBrokerLogEvent {
  fn on_log(&self, sender : MQTTBroker, e : &mut MQTTBrokerLogEventArgs);
}

impl <'a> MQTTBroker<'a> {
  pub fn on_log(&self) -> &'a dyn MQTTBrokerLogEvent;
  pub fn set_on_log(&mut self, value : &'a dyn MQTTBrokerLogEvent);
  ...
}

Remarks

This event fires once for each log message generated by the struct. The verbosity is controlled by the LogLevel setting.

LogLevel indicates the level of the Message. Possible values are:

LogType identifies the type of log entry. Possible values are:

• Info: General information about the struct.
• Session: Session status messages.
• Frame: Frame status messages.

on_message_received event (MQTTBroker Struct)

Fires when a new message is received from a client.

Syntax

// MQTTBrokerMessageReceivedEventArgs carries the MQTTBroker MessageReceived event's parameters.
pub struct MQTTBrokerMessageReceivedEventArgs {
  fn connection_id(&self) -> i32
  fn client_id(&self) -> &String
  fn message_id(&self) -> i64
}

// MQTTBrokerMessageReceivedEvent defines the signature of the MQTTBroker MessageReceived event's handler function.
pub trait MQTTBrokerMessageReceivedEvent {
  fn on_message_received(&self, sender : MQTTBroker, e : &mut MQTTBrokerMessageReceivedEventArgs);
}

impl <'a> MQTTBroker<'a> {
  pub fn on_message_received(&self) -> &'a dyn MQTTBrokerMessageReceivedEvent;
  pub fn set_on_message_received(&mut self, value : &'a dyn MQTTBrokerMessageReceivedEvent);
  ...
}

Remarks

This event fires each time a message is received from a client.

on_message_receiving event (MQTTBroker Struct)

Fires when a message is initially received from a client.

Syntax

// MQTTBrokerMessageReceivingEventArgs carries the MQTTBroker MessageReceiving event's parameters.
pub struct MQTTBrokerMessageReceivingEventArgs {
  fn connection_id(&self) -> i32
  fn client_id(&self) -> &String
  fn message_id(&self) -> i64
  fn dup(&self) -> bool
  fn qo_s(&self) -> i32
  fn retain(&self) -> bool
  fn packet_id(&self) -> i32
}

// MQTTBrokerMessageReceivingEvent defines the signature of the MQTTBroker MessageReceiving event's handler function.
pub trait MQTTBrokerMessageReceivingEvent {
  fn on_message_receiving(&self, sender : MQTTBroker, e : &mut MQTTBrokerMessageReceivingEventArgs);
}

impl <'a> MQTTBroker<'a> {
  pub fn on_message_receiving(&self) -> &'a dyn MQTTBrokerMessageReceivingEvent;
  pub fn set_on_message_receiving(&mut self, value : &'a dyn MQTTBrokerMessageReceivingEvent);
  ...
}

Remarks

The MessageReceiving event fires once for each incoming message immediately after it is received from a client.

• MessageId: A unique identifier for this message.
• DUP: Whether or not the server has indicated that this message is a duplicate of another message sent previously.
• QoS: The message's QoS level.
• Retain: Whether or not this message was received as a result of subscribing to a topic.
• PacketId: The message packet Id. This will always be -1 if QoS is 0.

on_message_sending event (MQTTBroker Struct)

Fires when a message is initially sent to a client.

Syntax

// MQTTBrokerMessageSendingEventArgs carries the MQTTBroker MessageSending event's parameters.
pub struct MQTTBrokerMessageSendingEventArgs {
  fn connection_id(&self) -> i32
  fn client_id(&self) -> &String
  fn message_id(&self) -> i64
  fn dup(&self) -> bool
  fn qo_s(&self) -> i32
  fn retain(&self) -> bool
  fn packet_id(&self) -> i32
}

// MQTTBrokerMessageSendingEvent defines the signature of the MQTTBroker MessageSending event's handler function.
pub trait MQTTBrokerMessageSendingEvent {
  fn on_message_sending(&self, sender : MQTTBroker, e : &mut MQTTBrokerMessageSendingEventArgs);
}

impl <'a> MQTTBroker<'a> {
  pub fn on_message_sending(&self) -> &'a dyn MQTTBrokerMessageSendingEvent;
  pub fn set_on_message_sending(&mut self, value : &'a dyn MQTTBrokerMessageSendingEvent);
  ...
}

Remarks

The MessageSending fires once for each outgoing message immediately after it is sent to a client.

• MessageId: A unique identifier for this message.
• DUP: Whether or not the server has indicated that this message is a duplicate of another message sent previously.
• QoS: The message's QoS level.
• Retain: Whether or not this message was received as a result of subscribing to a topic.
• PacketId: The message packet Id. This will always be -1 if QoS is 0.

on_message_sent event (MQTTBroker Struct)

Fires after a message is successfully delivered to a client, confirming transmission.

Syntax

// MQTTBrokerMessageSentEventArgs carries the MQTTBroker MessageSent event's parameters.
pub struct MQTTBrokerMessageSentEventArgs {
  fn connection_id(&self) -> i32
  fn client_id(&self) -> &String
  fn message_id(&self) -> i64
}

// MQTTBrokerMessageSentEvent defines the signature of the MQTTBroker MessageSent event's handler function.
pub trait MQTTBrokerMessageSentEvent {
  fn on_message_sent(&self, sender : MQTTBroker, e : &mut MQTTBrokerMessageSentEventArgs);
}

impl <'a> MQTTBroker<'a> {
  pub fn on_message_sent(&self) -> &'a dyn MQTTBrokerMessageSentEvent;
  pub fn set_on_message_sent(&mut self, value : &'a dyn MQTTBrokerMessageSentEvent);
  ...
}

Remarks

This event fires each time a message is delivered to a client.

on_outgoing_message_status event (MQTTBroker Struct)

Fired to provide the current delivery status of an outgoing message. Includes success or failure metadata.

Syntax

// MQTTBrokerOutgoingMessageStatusEventArgs carries the MQTTBroker OutgoingMessageStatus event's parameters.
pub struct MQTTBrokerOutgoingMessageStatusEventArgs {
  fn connection_id(&self) -> i32
  fn client_id(&self) -> &String
  fn message_id(&self) -> i64
  fn dup(&self) -> bool
  fn qo_s(&self) -> i32
  fn retain(&self) -> bool
  fn packet_id(&self) -> i32
  fn state(&self) -> i32
}

// MQTTBrokerOutgoingMessageStatusEvent defines the signature of the MQTTBroker OutgoingMessageStatus event's handler function.
pub trait MQTTBrokerOutgoingMessageStatusEvent {
  fn on_outgoing_message_status(&self, sender : MQTTBroker, e : &mut MQTTBrokerOutgoingMessageStatusEventArgs);
}

impl <'a> MQTTBroker<'a> {
  pub fn on_outgoing_message_status(&self) -> &'a dyn MQTTBrokerOutgoingMessageStatusEvent;
  pub fn set_on_outgoing_message_status(&mut self, value : &'a dyn MQTTBrokerOutgoingMessageStatusEvent);
  ...
}

Remarks

The OutgoingMessageStatus event fires each time an outgoing message's state is updated.

• MessageId: A unique identifier for this message.
• DUP: Whether or not the server has indicated that this message is a duplicate of another message sent previously.
• QoS: The message's QoS level.
• Retain: Whether or not this message is a retained message.
• PacketId: The message packet Id. This will always be -1 if QoS is 0.
• State: Information about the outgoing message's state.
  • 1 - Outgoing message is waiting to be sent
  • 2 - For an outgoing QoS 1 message, which has been sent to the client and waiting for the PUBACK. When the PUBACK is received, the state will change to 10.
  • 3 - For an outgoing QoS 2 message, which has been sent to the client and waiting for the PUBREC.
  • 4 - For an outgoing QoS 2 message, which has received the PUBREC, prior to sending the PUBREL for it.
  • 5 - For an outgoing QoS 2 message, which has sent the PUBREL. When the PUBCOMP is received, the state will change to 10.
  • 10 - Message successfully sent.

on_session_removed event (MQTTBroker Struct)

Fired when a client session is removed, indicating all resources associated with the session are cleaned up.

Syntax

// MQTTBrokerSessionRemovedEventArgs carries the MQTTBroker SessionRemoved event's parameters.
pub struct MQTTBrokerSessionRemovedEventArgs {
  fn client_id(&self) -> &String
}

// MQTTBrokerSessionRemovedEvent defines the signature of the MQTTBroker SessionRemoved event's handler function.
pub trait MQTTBrokerSessionRemovedEvent {
  fn on_session_removed(&self, sender : MQTTBroker, e : &mut MQTTBrokerSessionRemovedEventArgs);
}

impl <'a> MQTTBroker<'a> {
  pub fn on_session_removed(&self) -> &'a dyn MQTTBrokerSessionRemovedEvent;
  pub fn set_on_session_removed(&mut self, value : &'a dyn MQTTBrokerSessionRemovedEvent);
  ...
}

Remarks

The client with the associated ClientId will also be removed from the sessions collection when this event returns.

on_session_request event (MQTTBroker Struct)

Fires when a new session is requested.

Syntax

// MQTTBrokerSessionRequestEventArgs carries the MQTTBroker SessionRequest event's parameters.
pub struct MQTTBrokerSessionRequestEventArgs {
  fn connection_id(&self) -> i32
  fn client_id(&self) -> &String
  fn user_name(&self) -> &String
  fn password(&self) -> &String
  fn is_new(&self) -> bool
  fn accept(&self) -> bool
  fn set_accept(&self, value : bool)
}

// MQTTBrokerSessionRequestEvent defines the signature of the MQTTBroker SessionRequest event's handler function.
pub trait MQTTBrokerSessionRequestEvent {
  fn on_session_request(&self, sender : MQTTBroker, e : &mut MQTTBrokerSessionRequestEventArgs);
}

impl <'a> MQTTBroker<'a> {
  pub fn on_session_request(&self) -> &'a dyn MQTTBrokerSessionRequestEvent;
  pub fn set_on_session_request(&mut self, value : &'a dyn MQTTBrokerSessionRequestEvent);
  ...
}

Remarks

UserName and Password contain authentication credentials which can be verified in this event.

IsNew denotes whether this is a clean session from the client.

Accept can be set to false to reject the client. Set Accept to true to accept this client.

Example: broker.OnSessionRequest += (s,e) => { // Check e.UserName and e.Password if needed // Set Accept to true to accept the session request e.Accept = true; };

on_ssl_client_authentication event (MQTTBroker Struct)

This event is fired when the client presents its credentials to the server.

Syntax

// MQTTBrokerSSLClientAuthenticationEventArgs carries the MQTTBroker SSLClientAuthentication event's parameters.
pub struct MQTTBrokerSSLClientAuthenticationEventArgs {
  fn connection_id(&self) -> i32
  fn cert_encoded(&self) -> &[u8]
  fn cert_subject(&self) -> &String
  fn cert_issuer(&self) -> &String
  fn status(&self) -> &String
  fn accept(&self) -> bool
  fn set_accept(&self, value : bool)
}

// MQTTBrokerSSLClientAuthenticationEvent defines the signature of the MQTTBroker SSLClientAuthentication event's handler function.
pub trait MQTTBrokerSSLClientAuthenticationEvent {
  fn on_ssl_client_authentication(&self, sender : MQTTBroker, e : &mut MQTTBrokerSSLClientAuthenticationEventArgs);
}

impl <'a> MQTTBroker<'a> {
  pub fn on_ssl_client_authentication(&self) -> &'a dyn MQTTBrokerSSLClientAuthenticationEvent;
  pub fn set_on_ssl_client_authentication(&mut self, value : &'a dyn MQTTBrokerSSLClientAuthenticationEvent);
  ...
}

Remarks

This event enables the server to decide whether or not to continue. The accept parameter is a recommendation on whether to continue or to 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").

on_ssl_status event (MQTTBroker Struct)

This event is fired to show the progress of the secure connection.

Syntax

// MQTTBrokerSSLStatusEventArgs carries the MQTTBroker SSLStatus event's parameters.
pub struct MQTTBrokerSSLStatusEventArgs {
  fn connection_id(&self) -> i32
  fn message(&self) -> &String
}

// MQTTBrokerSSLStatusEvent defines the signature of the MQTTBroker SSLStatus event's handler function.
pub trait MQTTBrokerSSLStatusEvent {
  fn on_ssl_status(&self, sender : MQTTBroker, e : &mut MQTTBrokerSSLStatusEventArgs);
}

impl <'a> MQTTBroker<'a> {
  pub fn on_ssl_status(&self) -> &'a dyn MQTTBrokerSSLStatusEvent;
  pub fn set_on_ssl_status(&mut self, value : &'a dyn MQTTBrokerSSLStatusEvent);
  ...
}

Remarks

The event is fired for informational and logging purposes only. It is used to track the progress of the connection.

on_subscribe event (MQTTBroker Struct)

Fires when a client requests to subscribe to a topic.

Syntax

// MQTTBrokerSubscribeEventArgs carries the MQTTBroker Subscribe event's parameters.
pub struct MQTTBrokerSubscribeEventArgs {
  fn connection_id(&self) -> i32
  fn client_id(&self) -> &String
  fn topic_filter(&self) -> &String
  fn requested_qo_s(&self) -> i32
  fn return_code(&self) -> i32
  fn set_return_code(&self, value : i32)
}

// MQTTBrokerSubscribeEvent defines the signature of the MQTTBroker Subscribe event's handler function.
pub trait MQTTBrokerSubscribeEvent {
  fn on_subscribe(&self, sender : MQTTBroker, e : &mut MQTTBrokerSubscribeEventArgs);
}

impl <'a> MQTTBroker<'a> {
  pub fn on_subscribe(&self) -> &'a dyn MQTTBrokerSubscribeEvent;
  pub fn set_on_subscribe(&mut self, value : &'a dyn MQTTBrokerSubscribeEvent);
  ...
}

Remarks

The ClientId is used to identify this client in subsequent actions.

The TopicFilter is the requested topic the client wishes to subscribe to.

The RequestedQoS is the client's preferred QoS level.

ReturnCode is used to confirm the maximum QoS level granted for this subscription or indicate a failure. This can be less than the client's RequestedQoS.

on_unsubscribe event (MQTTBroker Struct)

Fires when a client unsubscribes from a topic, removing its subscription data.

Syntax

// MQTTBrokerUnsubscribeEventArgs carries the MQTTBroker Unsubscribe event's parameters.
pub struct MQTTBrokerUnsubscribeEventArgs {
  fn connection_id(&self) -> i32
  fn client_id(&self) -> &String
  fn topic_filter(&self) -> &String
}

// MQTTBrokerUnsubscribeEvent defines the signature of the MQTTBroker Unsubscribe event's handler function.
pub trait MQTTBrokerUnsubscribeEvent {
  fn on_unsubscribe(&self, sender : MQTTBroker, e : &mut MQTTBrokerUnsubscribeEventArgs);
}

impl <'a> MQTTBroker<'a> {
  pub fn on_unsubscribe(&self) -> &'a dyn MQTTBrokerUnsubscribeEvent;
  pub fn set_on_unsubscribe(&mut self, value : &'a dyn MQTTBrokerUnsubscribeEvent);
  ...
}

Remarks

The TopicFilter shows the topic this client is unsubscribing from.

Config Settings (MQTTBroker Struct)

TCPClient Config Settings

SSL Config Settings

-----BEGIN CERTIFICATE-----
MIIEKzCCAxOgAwIBAgIRANTET4LIkxdH6P+CFIiHvTowDQYJKoZIhvcNAQELBQAw
... Intermediate Cert ...
eWHV5OW1K53o/atv59sOiW5K3crjFhsBOd5Q+cJJnU+SWinPKtANXMht+EDvYY2w
F0I1XhM+pKj7FjDr+XNj
-----END CERTIFICATE-----
\r \n
-----BEGIN CERTIFICATE-----
MIIEFjCCAv6gAwIBAgIQetu1SMxpnENAnnOz1P+PtTANBgkqhkiG9w0BAQUFADBp
... Root Cert ...
d8q23djXZbVYiIfE9ebr4g3152BlVCHZ2GyPdjhIuLeH21VbT/dyEHHA
-----END CERTIFICATE-----

-----BEGIN CERTIFICATE-----
MIIEKzCCAxOgAwIBAgIRANTET4LIkxdH6P+CFIiHvTowDQYJKoZIhvcNAQELBQAw
... Intermediate Cert ...
eWHV5OW1K53o/atv59sOiW5K3crjFhsBOd5Q+cJJnU+SWinPKtANXMht+EDvYY2w
F0I1XhM+pKj7FjDr+XNj
-----END CERTIFICATE-----
\r \n
-----BEGIN CERTIFICATE-----
MIIEFjCCAv6gAwIBAgIQetu1SMxpnENAnnOz1P+PtTANBgkqhkiG9w0BAQUFADBp
... Root Cert ...
d8q23djXZbVYiIfE9ebr4g3152BlVCHZ2GyPdjhIuLeH21VbT/dyEHHA
-----END CERTIFICATE-----

-----BEGIN CERTIFICATE-----
MIIEKzCCAxOgAwIBAgIRANTET4LIkxdH6P+CFIiHvTowDQYJKoZIhvcNAQELBQAw
... Intermediate Cert...
eWHV5OW1K53o/atv59sOiW5K3crjFhsBOd5Q+cJJnU+SWinPKtANXMht+EDvYY2w
F0I1XhM+pKj7FjDr+XNj
-----END CERTIFICATE-----
\r \n
-----BEGIN CERTIFICATE-----
MIIEFjCCAv6gAwIBAgIQetu1SMxpnENAnnOz1P+PtTANBgkqhkiG9w0BAQUFADBp
... Root Cert...
d8q23djXZbVYiIfE9ebr4g3152BlVCHZ2GyPdjhIuLeH21VbT/dyEHHA
-----END CERTIFICATE-----

Socket Config Settings

Base Config Settings

Trappable Errors (MQTTBroker Struct)

MQTTBroker Errors

TCPClient Errors

SSL Errors

TCP/IP Errors