STOMP Class

Properties Methods Events Configuration Settings Errors

A simple but powerful STOMP client implementation.

Syntax

ipworksiot.stomp()

Remarks

The STOMP class provides an easy-to-use STOMP client implementation that supports STOMP versions 1.1 and 1.2. The class supports both plaintext and TLS-enabled connections over TCP.

Connecting

Connecting to a STOMP server is easy; in the simplest case just call the Connect method, passing the server's hostname and port number.

When connecting to a STOMP server, the class sends information from the following properties, if populated:

In addition to the above properties, the following configuration settings can be set before connecting (though in most cases this is not necessary):

SupportedVersions: Controls which STOMP versions the class advertises support for.
VirtualHost: Controls the virtual host to connect to. If left empty (default), the value from RemoteHost is used.

Subscriptions & Receiving Messages

The Subscribe and Unsubscribe methods are used to subscribe to and unsubscribe from message destinations on the server.

When Subscribe is called, it will return a subscription Id. To unsubscribe, pass this subscription Id to the Unsubscribe method.

After subscribing to a message destination, any messages received will cause the MessageIn event to fire.

Basic Subscriptions Example

stomp1.OnMessageIn += (s, e) => {
  Console.WriteLine("Received message from destination '" + e.Destination + "':");
  Console.WriteLine(e.Data);
};

string subId = stomp1.Subscribe("test/a/b", false);
// Some time later...
stomp1.Unsubscribe(subId);

Refer to Subscribe, Unsubscribe, and MessageIn for more information about subscriptions and receiving messages.

Sending Messages

To send messages, use the SendMessage and SendData methods. SendMessage is used to send messages with string payloads, while SendData is used to send messages with binary payloads.

Send String Message Example

stomp1.SendMessage("test/a/b", "Hello, world!");

Send Binary Message Example

byte[] fileContent = File.ReadAllBytes("C:\test\stuff.dat");
stomp1.SendData("test/a/b", fileContent);

Refer to SendMessage and SendData for more information about sending messages.

Using Transactions

STOMP transactions are used to group messages together for processing on the server. Messages sent as part of a transaction will not be delivered by the server until the transaction is committed. If the transaction is aborted, the server will discard the messages without attempting to deliver them.

Basic Transaction Example

// Open a new transaction.
stomp1.BeginTransaction("txn1");
// Set the Transaction property to make sure that messages are sent as part of the transaction.
stomp1.Transaction = "txn1";

stomp1.SendMessage("test/a/b", "Hello, world!");
stomp1.SendMessage("test/a/b", "This is a test.");
stomp1.SendMessage("test/a/b", "Another test!");

// At this point, none of the messages sent above would have been delivered to any clients
// subscribed to the "test/a/b" destination yet, because the transaction is still open.

// If we close and commit the transaction, the server will then deliver the messages to subscribers,
// queue them, or process them in another manner; the behavior is server-dependent.
stomp1.CommitTransaction("txn1");

// Or, the transaction can be aborted, in which case the server will discard the messages
// without delivering them to the subscribers.
//stomp1.AbortTransaction("txn1");

// Reset (or change) the Transaction property after committing or aborting a transaction
// so that future messages are not associated with the previous transaction.
stomp1.Transaction = "";

Refer to BeginTransaction for more information about using transactions.

Property List

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


Connected	Triggers a connection or disconnection.
ContentType	The content type of the outgoing message.
Firewall	A set of properties related to firewall access.
Headers	User-defined headers added to outgoing messages.
IncomingHeartbeat	Specifies the server-to-class heartbeat timing.
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.
OutgoingHeartbeat	Specifies the class-to-server heartbeat timing.
ParsedHeaders	Headers parsed from incoming messages.
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 STOMP server (default is 61613). The default port for SSL is 61612.
RequestReceipts	Whether the class should request that the server provide message receipts.
SSLAcceptServerCert	Instructs the class to unconditionally accept the server certificate that matches the supplied certificate.
SSLCert	The certificate to be used during SSL negotiation.
SSLEnabled	Whether TLS/SSL is enabled.
SSLServerCert	The server certificate for the last established connection.
Subscriptions	Collection of current subscriptions.
Timeout	A timeout for the class.
TransactionId	Specifies the Id of the transaction that outgoing messages are associated with.
User	A username if authentication is to be used.

Method List

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


AbortTransaction	Aborts an existing transaction.
AddHeader	Adds a custom header to send with outgoing messages.
BeginTransaction	Begins a new transaction.
CommitTransaction	Commits an existing transaction.
Config	Sets or retrieves a configuration setting.
Connect	Connects to the remote host.
Disconnect	Disconnects from the remote host.
DoEvents	Processes events from the internal message queue.
Interrupt	Interrupt the current action and disconnects from the remote host.
Reset	Reset the class.
ResetHeaders	Clear the user-defined headers collection.
SendData	Publishes a message with a raw data payload.
SendMessage	Publishes a message with a string payload.
Subscribe	Subscribes to a message destination on the server.
Unsubscribe	Removes an existing subscription.

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	Fired immediately after a connection completes (or fails).
ConnectionStatus	Fired to indicate changes in connection state.
Disconnected	Fired when a connection is closed.
Error	Fired when a class or protocol error occurs.
Log	Fired once for each log message.
MessageIn	Fired when a message has been received.
MessageOut	Fired after a message has been sent.
ReadyToSend	Fired when the class is ready to send data.
ReceiptIn	Fires when the class receives a receipt from the server.
ReceiptOut	Fires when the class sends a STOMP frame that includes a 'receipt' header.
SSLServerAuthentication	Fired after the server presents its certificate to the client.
SSLStatus	Shows the progress of the secure connection.
Subscribed	Fired when the class has subscribed to a message destination on the server.
Unsubscribed	Fired when the class has unsubscribed from a message destination on the server.

Configuration Settings

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


AckTransactionId	The transaction Id to include when sending a message acknowledgment.
CollapseHeaders	Whether the class should collapse headers on incoming messages.
ErrorHeaders	Raw headers from a STOMP 'ERROR' frame.
LogLevel	The level of detail that is logged.
OpenTransactions	A comma-separated list of currently open transactions.
ProtocolVersion	The agreed-upon STOMP protocol version that the class is using.
RequestAckReceipts	Whether the class should request receipts for any message acknowledgments that are sent.
RequestSubscriptionReceipts	Whether the class should request receipts when sending subscribe and unsubscribe requests.
RequestTransactionReceipts	Whether the class should request receipts when sending begin, commit, and abort transaction requests.
SendCustomFrame	Sends a frame constructed using the supplied hex byte string.
ServerInfo	Information about the currently connected server.
SessionId	The server-assigned session Id.
SupportedVersions	Which STOMP protocol versions the class should advertise support for when connecting.
VirtualHost	The virtual host to connect to.
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.
SSLAcceptAnyServerCert	Whether to trust any certificate presented by the server.
SSLCACerts	A newline separated list of CA certificate to use during SSL client authentication.
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.
SSLNegotiatedCipher	Returns the negotiated ciphersuite.
SSLNegotiatedCipherStrength	Returns the negotiated ciphersuite strength.
SSLNegotiatedCipherSuite	Returns the negotiated ciphersuite.
SSLNegotiatedKeyExchange	Returns the negotiated key exchange algorithm.
SSLNegotiatedKeyExchangeStrength	Returns the negotiated key exchange algorithm strength.
SSLNegotiatedVersion	Returns the negotiated protocol version.
SSLProvider	The name of the security provider to use.
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 UseInternalSecurityAPI is True.
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.
UseInternalSecurityAPI	Tells the class whether or not to use the system security libraries or an internal implementation.

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