Camunda Message Streaming

This library allows BPMN designers to declaratively define what values, from an incoming JSON based message, will be used to correlate to a Process or a Process Instance (e.g. Execution). Message values are evaluated at runtime using JSON Path expressions which are stored within the BPMN.

The following Message Events are supported:

Start Events

Intermediate Catch Events

Interrupting & Non-interrupting Boundary Catch Events

Receive Tasks

The following extension semantics are currently supported

Using the modeler you can assign extensions to a Start Event, Message Catch Event, Boundary Event, or a Receive Task.

Note: {prefix} defaults to ultimate.workflow but can be configured via the application properties

{prefix}.topic={topic-name}

Sets the topic value you wish to save with the extension data, to be used for message consumers to establish connections for correlation messages.

Example usage:

String topic = messageTypeExtensionData.getTopic();

topicContainerManager.createOrStartConsumer(topic, listener);

{prefix}.business-process-key={json-path}

Assigns the business process key that will be used to start a new process or match on a currently running process

Note: This can also be declared as {prefix}.match-var.business-process-key={json-path} Java equivalent:

processEngine.getRuntimeService()
    .createMessageCorrelation("com.acme.messages.important-event")
    .processInstanceBusinessKey("key")

{prefix}.match-var.{variable-name}={json-path}

Creates a match requirement on a variable whose name is defined by {variable-name}

Java equivalent:

processEngine.getRuntimeService()
    .createMessageCorrelation("com.acme.messages.important-event")
    .processVariableValueEquals("key", "value")

{prefix}.match-local-var.{variable-name}={json-path}

Creates a match requirement on a local variable whose name is defined by {variable-name}

Java equivalent:

processEngine.getRuntimeService()
    .createMessageCorrelation("com.acme.messages.important-event")
    .variableValueEquals("key", "value")

{prefix}.input-var.{variable-name}={json-path}

Sets a variable, whose name is defined by {variable-name}

Java equivalent:

processEngine.getRuntimeService()
    .createMessageCorrelation("com.acme.messages.important-event")
    .setVariable("key", "value")

Links

• Getting Started Guide
• Correlation Logic Example
• References