[MESOS-5936] Operator SUBSCRIBE api should provdide more task metadata than just state changes

• Type: Improvement
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.0.0
• Fix Version/s: 1.1.0
• Component/s: HTTP API, json api
• Labels: mesosphere
• Target Version/s: 1.1.0
• Epic Link: Operator API v1 Improvements
• Assignee: Zhitao Li
• Reporter: Steven Schlansker
• Shepherd: Anand Mazumdar
• Created: 29/Jul/16 22:20
• Updated: 08/Oct/16 04:18
• Resolved: 08/Oct/16 04:18

Description

I am starting to use the new Operator event subscription API to get notified of task changes. The initial TASK_STAGING event has a good amount of information, but unfortunately future events like TASK_RUNNING include almost no metadata. This means that any task information that cannot be determined until the task launches (in my particular case, the IP address assigned by the Docker containerizer) is not available through the event stream.

Here is a gist of a single task that was launched, comparing the information in 'state.json' vs the subscribed events:

https://gist.github.com/stevenschlansker/c1d32aa9ce37a73f9c4d64347397d3b8

Note particularly how the IP address never shows in the event stream.

Task updates should expose the task information that changed. If this is too onerous, maybe the subscription call can take optional sets of data to include, with the first one being additional task metadata.

A possible workaround is to use the task events to fetch 'state.json' separately, but this is inherently racy and totally undermines the utility of the event stream api.

Issue Links

• contains: MESOS-6066 Operator SUBSCRIBE api should include timestamps