Target order in Web UI not stable

[Jean-Daniel]

What did you do?
Reload the target page in the prometheus Web Admin UI

What did you expect to see?
That the order of the target is the same across page reload

What did you see instead? Under which circumstances?
The target are display in random order that vary from one request to the other

Environment
Ubuntu 16.04

• System information:
  Linux 4.4.0-53-generic x86_64

• Prometheus version:
  prometheus, version 1.5.1 (branch: master, revision: c4686f7)

[gouthamve]

This is expected behaviour, we are ranging over a map. Can we know the usecase for consistent ordering? Thanks, Goutham

[Jean-Daniel]

Improving readability.

Sometimes, I have to refresh the page to check the status of a target did change from Down to Up, and having to search for the line position after each refresh is a little annoying, especially when the target list become large.

Sorting target by endpoint would also simplify the lookup of a specific target in the list.

[juliusv]

Agreed, having a consistent sort order would be nice for the refresh-and-check use case.

[juliusv]

Actually I'm not sure why it's not sorted already. https://golang.org/pkg/text/template/ says for ranges in templates: "If the value is a map and the keys are of basic type with a defined order ("comparable"), the elements will be visited in sorted key order.". And .TargetPools is a map[string][]*retrieval.Target, and strings are definitely comparable :)

[juliusv]

Ah of course. The jobs are sorted, but the targets ([]*retrieval.Target) within a job are not. So we just need to sort that slice.

[juliusv]

PR out in #2548

[lock]

This thread has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for related bugs.