Message Send connector
The Message Send connector can publish or correlate BPMN messages.
It either calls the PublishMessage RPC of the Zeebe API to send messages buffered by Zeebe, or the Correlate a message REST API to get the ID of the process instance that received the message without buffering.
The element template allows you to select the mode:
publish message (with buffer)correlate message (with result)
and fill all parameters directly in the modeler.
Publish message (buffered) parameters
| Parameter | Type | Description | Default / Optional |
|---|---|---|---|
| Message name | string | Name of the message. Must match a receiving message event. | Required |
| Correlation key | string | Value for correlating with a process instance. Can be empty to start a new instance. | Optional |
| Payload | JSON | Variables to transfer to the receiving process instance. Example: {"customerName": cust_name}. Multiple variables can be defined. | Required |
| Time to live | int | Time in milliseconds to buffer the message. | No buffer |
| Message ID | string | Unique message ID for idempotency. Ensures the message is delivered only once until correlated. | Optional |
| Tenant ID | string | Tenant ID of the receiving instance. | <default> |
| Request timeout | int | Timeout for the publish message command. | Connector default |
Response
| Field | Type | Description |
|---|---|---|
| messageKey | int64 | Unique ID of the published message |
| tenantId | string | Tenant ID of the message |
Correlate message (with result) parameters
| Parameter | Type | Description | Default / Optional |
|---|---|---|---|
| Message name | string | Name of the message. Must match a receiving message event. | Required |
| Correlation key | string | Value for correlating with a process instance. Can be empty to start a new instance. | Optional |
| Payload | JSON | Variables to transfer to the receiving process instance. Example: {"customerName": cust_name}. Multiple variables can be defined. | Required |
| Tenant ID | string | Tenant ID of the receiving instance. | <default> |
| Request timeout | int | Timeout for the correlate message command. | Connector default |
Response
| Field | Type | Description |
|---|---|---|
| messageKey | int64 | Unique ID of the correlated message |
| processInstanceKey | int64 | Key of the first process instance the message correlated with |
| tenantId | string | Tenant ID of the message |
The connector raises an incident with a detailed error message containing the 404 status
Not foundif the message could not be correlated.