The Message Handler accepts amphorae heartbeats and stores them
The Controller's Message Handler accepts health updates from amphorae and stores them in the HA database. The updates are very-low-
Blueprint information
- Status:
- Not started
- Approver:
- None
- Priority:
- Undefined
- Drafter:
- Jamie McCarthy
- Direction:
- Needs approval
- Assignee:
- None
- Definition:
- New
- Series goal:
- None
- Implementation:
-
Unknown
- Milestone target:
- None
- Started by
- Completed by
Related branches
Related bugs
Sprints
Whiteboard
We've decided that we're using a HealthMixIn class, per amphora-
We've decided that an amphora's health_daemon will confirm its identity to the handler by combining a format version number, its amphora UUID (different from its nova instance ID), and a sequence number, and cryptographically signing it. This must fit into 512 bytes to guarantee a single UDP packet. Using openssl seems like overkill. Possible python module: https:/
I believe that as scaling becomes important, heartbeats will be aggregated before updates are written, perhaps at a 1-second resolution (so e.g. a single MySQL UPDATE can commit all changes from that controller in that second). But to try to do this optimization for 0.5 would be premature.
Work Items
Work items:
Decide on a thread framework/model: TODO
Figure out the best/standard module to open the UDP socket listener and register a callback: TODO
Decide on a format to receive the amphora's UUID, sequence number, and version it: TODO
Decide which data store will be used (MySQL? in-memory dict?) and how to handle the first heartbeat: TODO
Decide how the public part of each amphora's key used to sign its heartbeats will be made available to the message handler: TODO
