Push Jobs Server Sent Events Feed

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The Push Jobs server provides feeds of events associated with actions, via the Server-Sent-Events (SSE) protocol. There are two SSE feeds available:

  1. Job Feed: Stream of events for a particular job
  2. Organization Feed: Stream of events for all jobs across an organization

Event Types

As mandated by the SSE protocol, each event has:

  • a type-specifier (event)
  • an ID (id)
  • data

The structure of an individual event appears as follows:

event: EVENT_TYPE
id: EVENT_ID
data: {"timestamp": "2014-07-10 05:17:44.995958Z", ...}
  • EVENT_TYPE varies depending on the stream you request. In a Job Feed you could receive start, quorum_vote, quorum_succeeded, run_start, run_complete, job_complete, rehab, and summary. In the Organization Feed you could receive start, job_complete, and start_of_history.
  • EVENT_ID is not globally unique. It is an opaque string that is unique only to the individual stream.
  • data is a JSON object which content depends on the event. However, the JSON object for each event type includes a server-based timestamp in ISO8601 format.

In addition, SSE allows comments in the stream, indicated by a starting colon. Push Jobs Server uses comments to send “no-op” events every 15 (configurable) seconds, as a form of keepalive for the socket.

start

This event is issued when a job is requested.

Example Event

event: start
id: dcd37f50-2d77-4761-895b-33134dbf87d5
data: {"timestamp":"2014-07-10 05:17:44.995958Z","job":"768b8d57-3cd0-434c-9f98-77e52cb96b86","command":"chef-client","run_timeout":300,"user":"rebecca","quorum":3,"node_count":3}

where:

  • job is the Job ID. (Not present in Job Feed)
  • command is the command that was run
  • run_timeout is the timeout in seconds specified in the job request
  • user is the user making the job request
  • quorum is the number of clients required to accept the command as specified in the job request
  • node_count is the number of nodes in the request

quorum_vote

This event is issued as each node responds to the quorum request. (Not available in Organization Feed)

Example Event

event: quorum_vote
id: dcd37f50-2d77-4761-895b-33134dbf87d5
data: {"timestamp":"2014-07-10 05:17:44.995958Z","node":"NODE1","status":"success"}

where:

  • node is the name of the node responding to the vote
  • status is one of the following: client_died_while_voting (node went offline during voting), failure (node rejected the job), lost_availability (node become unavailable during voting), success (node accepted the job), unexpected_commit (node attempted to vote twice)

quorum_succeeded

This event is issued when the vote is complete, and the nodes are told to run the command. (Not available in Organization Feed)

Please note: there is no corresponding quorum_failed event. If the quorum fails, then the job_complete event will include a “quorum_failed” status.

Example Event

event: quorum_succeeded
id: dcd37f50-2d77-4761-895b-33134dbf87d5
data: {"timestamp": "2014-07-10 05:17:44.995958Z"}

run_start

This event is issued as each node acknowledges that it is running the command. (Not available in Organization Feed)

Example Event

event: run_start
id: dcd37f50-2d77-4761-895b-33134dbf87d5
data: {"timestamp":"2014-07-10 05:17:44.995958Z","node":"NODE1"}

where:

  • node is the name of the node

run_complete

This event is issued as each node completes the command. (Not available in Organization Feed)

Example Event

event: run_complete,
id: dcd37f50-2d77-4761-895b-33134dbf87d5
data: {"timestamp":"2014-07-10 05:17:44.995958Z","node":"NODE1","status":"crashed"}

where:

  • node is the name of the node
  • status is one of the following: client_died_while_running (node went offline before finishing the run), crashed (node terminated run without returning status), failure (run failed), run_nacked (node rejected the run after quorum was reached), run_nacked_while_running (node rejected the run after starting it), or success (the run completed successfully),

job_complete

This event is issued when the job completes.

Example Event

event: job_complete
id: dcd37f50-2d77-4761-895b-33134dbf87d5
data: {"timestamp":"2014-07-10 05:17:44.995958Z","job":"768b8d57-3cd0-434c-9f98-77e52cb96b86","status":"complete"}

where:

  • job is the Job ID (Not present in Job Feed)
  • status is one of the following: aborted (the job was aborted), complete (the job completed), quorum_failed (the command was not run on any nodes), or timed_out (the command timed out)

start_of_history

This synthetic event is issued when the Last-Event-ID header is not recognized. (Not available in Job Feed)

Example Event

event: start_of_history
id: dcd37f50-2d77-4761-895b-33134dbf87d5
data: {"timestamp":"2014-07-10 05:17:44.995958Z"}

rehab

This event is issued when the server detects an abnormality with a node and attempts to repair it. (Not available in Organization Feed)

event: rehab
id: dcd37f50-2d77-4761-895b-33134dbf87d5
data: {"timestamp":"2014-07-10 05:17:44.995958Z","node":"NODE1"}

summary

This event is issued when a request for the Job Feed comes in after the job has completed. (Not available in Organization Feed)

event: summary
id: dcd37f50-2d77-4761-895b-33134dbf87d5
data: {"timestamp":"2014-07-10 05:17:44.995958Z","id":"aaaaaaaaaaaa25fd67fa8715fd547d3d","command":"chef-client", ... }

where:

  • data is the same Job Summary you would get from the job/ID endpoint

Event Stream Examples

An event stream should follow a standard structure:

Job Feed (Normal Run Execution)

  1. start
  2. 0 or more quorum_vote
  3. quorum_succeeded
  4. 1 or more run_start
  5. 1 or more run_complete
  6. job_complete

Request

Accept: text/event-stream
GET /organizations/ORG_NAME/pushy/jobs_status_feed/JOBID

Response

The response will return something similar to:

event: start
id: dcd37f50-2d77-4761-895b-33134dbf87d1
data: {"timestamp":"2014-07-10 05:17:40.995958Z","command":"ls /etc/chef","run_timeout":300,"user":"rebecca","quorum":2,"node_count":2}

event: quorum_vote
id: dcd37f50-2d77-4761-895b-33134dbf87d2
data: {"timestamp":"2014-07-10 05:17:41.995958Z","node":"NODE1","status":"success"}

event: quorum_vote
id: dcd37f50-2d77-4761-895b-33134dbf87d3
timestamp:
data: {"timestamp":"2014-07-10 05:17:42.995958Z","node":"NODE2","status":"success"}

event: quorum_succeeded
id: dcd37f50-2d77-4761-895b-33134dbf87d4
data: {"timestamp":"2014-07-10 05:17:43.995958Z"}

event: run_start
id: dcd37f50-2d77-4761-895b-33134dbf87d5
data: {"timestamp":"2014-07-10 05:17:44.995958Z","node":"NODE1"}

event: run_start
id: dcd37f50-2d77-4761-895b-33134dbf87d6
data: {"timestamp":"2014-07-10 05:17:45.995958Z","node":"NODE2"}

event: run_complete
id: dcd37f50-2d77-4761-895b-33134dbf87d7
data: {"timestamp":"2014-07-10 05:17:46.995958Z","node":"NODE1","status":"success"}

event: run_complete
id: dcd37f50-2d77-4761-895b-33134dbf87d58
timestamp: "
data: {"timestamp":"2014-07-10 05:17:47.995958Z","node":"NODE2","status":"success"}

event: job_complete
id: dcd37f50-2d77-4761-895b-33134dbf87d9
data": {"timestamp":"2014-07-10 05:17:48.995958Z","status":"complete"}

Job Feed (Failed Quorum)

  1. start
  2. 1+ quorum_failed
  3. job_complete

Request

Accept: text/event-stream
GET /organizations/ORG_NAME/pushy/jobs_status_feed/JOBID

Response

The response will return something similar to:

event: start
id: dcd37f50-2d77-4761-895b-33134dbf87d1
data": {"timestamp":"2014-07-10 05:17:40.995958Z","command":"ls /etc/chef","run_timeout":300,"user":"rebecca","quorum":2,"node_count":2}

event: quorum_vote
id: dcd37f50-2d77-4761-895b-33134dbf87d2
data": {"timestamp":"2014-07-10 05:17:41.995958Z","node":"NODE","status":"failure"}

event: quorum_vote
id: dcd37f50-2d77-4761-895b-33134dbf87d3
data": {"timestamp":"2014-07-10 05:17:42.995958Z","node":"NODE2","status":"success"}

event: job_complete
id: dcd37f50-2d77-4761-895b-33134dbf87d9
data": {"timestamp":"2014-07-10 05:17:48.995958","status":"quorum_failed"}

Organization Feed

  1. start (job=B)
  2. job_complete (job=A)
  3. start (job=C)
  4. job_complete (job=C)
  5. job_complete (job=B)

Request

Accept: text/event-stream
GET /organizations/ORG_NAME/pushy/jobs_status_feed/JOBID

Response

The response will return something similar to:

event: start
id: dcd37f50-2d77-4761-895b-33134dbf87d1
data: {"timestamp":"2014-07-10 05:10:40.995958Z","job":"B","command":"chef-client","run_timeout":300,"user":"rebecca","quorum":2,"node_count":2}

event: job_complete
id: dcd37f50-2d77-4761-895b-33134dbf87d2
data: {"timestamp":"2014-07-10 05:15:48.995958Z","job":"A","status":"success"}

event: start
id: dcd37f50-2d77-4761-895b-33134dbf87d3
data: {"timestamp":"2014-07-10 05:17:40.995958Z","job":"C","command":"cat /etc/passwd","run_timeout":300,"user":"charles","quorum":2,"node_count":2}

event: job_complete
id: dcd37f50-2d77-4761-895b-33134dbf87d4
data: {"timestamp":"2014-07-10 05:17:41.995958Z","job":"C","status":"success"}

event: job_complete
id: dcd37f50-2d77-4761-895b-33134dbf87d5
data: {"timestamp":"2014-07-10 05:20:48.995958Z","job":"B","status":"success"}

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https://docs.chef.io/server_sent_events/