The MQTT driver supports reporters only. It is used to send MQTT message when items report.

Message Schema

An MQTT report uses this schema:

<mqtt schema>
<mqtt schema>.uuid

The item UUID. Each item enqueued into a Zuul pipeline is assigned a UUID which remains the same even as Zuul’s speculative execution algorithm re-orders pipeline contents.

<mqtt schema>.action

The reporter action name, e.g.: ‘start’, ‘success’, ‘failure’, ‘merge-failure’, …

<mqtt schema>.tenant

The tenant name.

<mqtt schema>.pipeline

The pipeline name.

<mqtt schema>.project

The project name.

<mqtt schema>.branch

The branch name.

<mqtt schema>.change_url

The change url.

<mqtt schema>.message

The report message.

<mqtt schema>.change

The change number.

<mqtt schema>.patchset

The patchset number.

<mqtt schema>.commit_id

The commit id number.

<mqtt schema>.owner

The owner username of the change.

<mqtt schema>.ref

The change reference.

<mqtt schema>.zuul_ref

The internal zuul change reference.

<mqtt schema>.trigger_time

The timestamp when the event was added to the scheduler.

<mqtt schema>.enqueue_time

The timestamp when the event was added to the pipeline.

<mqtt schema>.buildset

The buildset information.


The buildset global uuid.

<mqtt schema>.buildset.result

The buildset result

<mqtt schema>.buildset.builds

The list of builds.

<mqtt schema>.buildset.builds.job_name

The job name.

<mqtt schema>

The job voting status.

<mqtt schema>.buildset.builds.uuid

The build uuid (not present in start report).

<mqtt schema>.buildset.builds.execute_time

The build execute time.

<mqtt schema>.buildset.builds.start_time

The build start time (not present in start report).

<mqtt schema>.buildset.builds.end_time

The build end time (not present in start report).

<mqtt schema>.buildset.builds.log_url

The build log url (not present in start report).

<mqtt schema>.buildset.builds.web_url

The url to the build result page. Not present in start report.

<mqtt schema>.buildset.builds.result

The build results (not present in start report).

<mqtt schema>.buildset.builds.artifacts
Type: list

The build artifacts (not present in start report).

This is a list of dictionaries corresponding to the returned artifacts.

<mqtt schema>

The name of the artifact.

<mqtt schema>.buildset.builds.artifacts.url

The url of the artifact.

<mqtt schema>.buildset.builds.artifacts.metadata
Type: dict

The metadata of the artifact. This is a dictionary of arbitrary key values determined by the job.

Here is an example of a start message:

  'action': 'start',
  'tenant': '',
  'pipeline': 'check',
  'project': 'sf-jobs',
  'branch': 'master',
  'change_url': '',
  'message': 'Starting check jobs.',
  'trigger_time': '1524801056.2545864',
  'enqueue_time': '1524801093.5689457',
  'change': '3',
  'patchset': '1',
  'commit_id': '2db20c7fb26adf9ac9936a9e750ced9b4854a964',
  'owner': 'username',
  'ref': 'refs/changes/03/3/1',
  'zuul_ref': 'Zf8b3d7cd34f54cb396b488226589db8f',
  'buildset': {
    'uuid': 'f8b3d7cd34f54cb396b488226589db8f',
    'builds': [{
      'job_name': 'linters',
      'voting': True

Here is an example of a success message:

  'action': 'success',
  'tenant': '',
  'pipeline': 'check',
  'project': 'sf-jobs',
  'branch': 'master',
  'change_url': '',
  'message': 'Build succeeded.',
  'trigger_time': '1524801056.2545864',
  'enqueue_time': '1524801093.5689457',
  'change': '3',
  'patchset': '1',
  'commit_id': '2db20c7fb26adf9ac9936a9e750ced9b4854a964',
  'owner': 'username',
  'ref': 'refs/changes/03/3/1',
  'zuul_ref': 'Zf8b3d7cd34f54cb396b488226589db8f',
  'buildset': {
    'uuid': 'f8b3d7cd34f54cb396b488226589db8f',
    'builds': [{
      'job_name': 'linters',
      'voting': True
      'uuid': '16e3e55aca984c6c9a50cc3c5b21bb83',
      'execute_time': 1524801120.75632954,
      'start_time': 1524801179.8557224,
      'end_time': 1524801208.928095,
      'log_url': '',
      'web_url': '',
      'result': 'SUCCESS',
      'dependencies': [],
      'artifacts': [],

Connection Configuration

<mqtt connection>
<mqtt connection>.driver (required)

The connection must set driver=mqtt for MQTT connections.

<mqtt connection>.server
Default: localhost

MQTT server hostname or address to use.

<mqtt connection>.port
Default: 1883

MQTT server port.

<mqtt connection>.keepalive
Default: 60

Maximum period in seconds allowed between communications with the broker.

<mqtt connection>.user

Set a username for optional broker authentication.

<mqtt connection>.password

Set a password for optional broker authentication.

<mqtt connection>.ca_certs

A string path to the Certificate Authority certificate files to enable TLS connection.

<mqtt connection>.certfile

A strings pointing to the PEM encoded client certificate to enable client TLS based authentication. This option requires keyfile to be set too.

<mqtt connection>.keyfile

A strings pointing to the PEM encoded client private keys to enable client TLS based authentication. This option requires certfile to be set too.

<mqtt connection>.ciphers

A string specifying which encryption ciphers are allowable for this connection. More information in this openssl doc.

Reporter Configuration

A connection that uses the mqtt driver must be supplied to the reporter. Each pipeline must provide a topic name. For example:

- pipeline:
    name: check
        topic: "{tenant}/zuul/{pipeline}/{project}/{branch}/{change}"
        qos: 2

To report via MQTT message, the dictionaries passed to any of the pipeline reporter support the following attributes:


The MQTT topic to publish messages. The topic can be a format string that can use the following parameters: tenant, pipeline, project, branch, change, patchset and ref. MQTT topic can have hierarchy separated by /, more details in this doc

Default: 0

The quality of service level to use, it can be 0, 1 or 2. Read more in this guide