Publish events directly

You can publish a CloudEvents event directly to an Eventarc Advanced bus in a supported format using the Google Cloud CLI or by sending a request to the Eventarc Publishing REST API. You can also use the Eventarc client libraries to access the Eventarc APIs from a supported language.

The message must conform to the CloudEvents specification.

gcloud

  1. Open a terminal.

  2. You can publish events to a bus by using the gcloud beta eventarc message-buses publish command. For example:

    gcloud beta eventarc message-buses publish BUS_NAME \
    --avro-message=AVRO_MESSAGE
    Or: 
    gcloud beta eventarc message-buses publish BUS_NAME \
    --json-message=JSON_MESSAGE
    Or: 
    gcloud beta eventarc message-buses publish BUS_NAME \
    --event-data=DATA_PAYLOAD \
    --event-id=EVENT_ID \
    --event-source=EVENT_SOURCE \
    --event-type=EVENT_TYPE \
    --event-attributes=EVENT_ATTRIBUTE

    Replace the following:

    • BUS_NAME: the ID or fully qualified identifier of the bus to which to publish the event.

    You must use only one of the following:

    • AVRO_MESSAGE: the event message in an Avro format according to this specification.
    • JSON_MESSAGE: the event message in a JSON format according to this specification.
    • DATA_PAYLOAD: the data of a published event.

    If using the --event-data flag, you must also use the following:

    • EVENT_ID: the event identifier. Event producers must ensure that source + id is unique for each distinct event.
    • EVENT_SOURCE: the event source of a published event.
    • EVENT_TYPE: the type of event related to the originating occurrence.

    If using the --event-data flag, you can optionally use the following:

    • EVENT_ATTRIBUTE: the attributes of a published event. You can repeat the --event-attributes flag to add more attributes.

      Note that events might include any number of additional custom CloudEvents attributes with distinct names (also known as extension attributes).

Examples:

gcloud beta eventarc message-buses publish my-bus \
    --event-id=1234 \
    --event-type=event-provider.event.v1.eventType \
    --event-source="//event-provider/event/source" \
    --event-data='{"key": "value"}' \
    --event-attributes=attribute1=value
 

gcloud beta eventarc message-buses publish my-bus --json-message @- << EOF
{
    "specversion" : "1.0",
    "type" : "com.example.someevent",
    "source" : "google.cloud.storage.object.v1.finalized",
    "id" : "A234-1234-1234",
    "time" : "2024-04-05T17:31:00Z",
    "bucket" : "bucketName",
    "datacontenttype" : "application/json",
    "data":{"key": "value"}
}
EOF

REST API

To publish an event to a bus, use the projects.locations.messageBuses.publish method.

Before using any of the request data, make the following replacements:

  • The full resource name of the bus in the format projects/PROJECT_ID/locations/LOCATION/messageBuses/BUS_NAME

    Replace the following:

    • PROJECT_ID: the Google Cloud project ID for the bus project.
    • LOCATION: the region in which the bus is deployed—for example, us-central1.
    • BUS_NAME: the name of the bus to which to publish the event.
  • SPEC_VERSION: the version of the CloudEvents specification which the event uses—for example, 1.0.
  • EVENT_TYPE: the type of event related to the originating occurrence.
  • EVENT_SOURCE: the event source of a published event.
  • EVENT_ID: the event identifier. Producers must ensure that source + id is unique for each distinct event.
  • CONTENT_TYPE (optional): the content type of data value. If a JSON format event has no datacontenttype attribute, then it is assumed that the data is a JSON value conforming to the application/json media type.
  • DATA_PAYLOAD (optional): the event payload encoded into the media format specified by datacontenttype and adhering to dataschema when those attributes are present.

Request JSON body: 

{
"jsonMessage":
  "{\"specversion\":\"SPEC_VERSION\",
  \"type\":\"EVENT_TYPE\",
  \"source\":\"EVENT_SOURCE\",
  \"id\":\"EVENT_ID\",
  \"datacontenttype\":\"CONTENT_TYPE\",
  \"data\":\"DATA_PAYLOAD\"}"
}

To send your request, expand one of these options:

If successful, the server returns an HTTP 200 OK status code and the empty response body in JSON format: 

200 OK

{}

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