prometheus / prometheus/client_js
enhancement: Cluster worker scrape timeouts/errors should be recorded
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- Dominant language
- JavaScript
- Stars
- 3.5k
- Forks
- 429
- Avg merge
- 3d 3h
- Merged PRs (30d)
- 22
Description
If a worker is heavily loaded or otherwise pathologically performant, a cluster master may time out when scraping that worker (https://github.com/siimon/prom-client/blob/master/lib/cluster.js#L51-L61). The cluster master then returns an incomplete set of data (since some subset of workers have returned data, but not necessarily all). I think it makes sense to record an error counter for clustered worker scrapes, such that it's exposed to downstream consumers.
If this feature makes sense, I am happy to implement it! (cc @dt-rush)
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Research direction
Start in lib/cluster.js at lines 51-61, where the cluster master scrapes workers and handles timeout or error cases. Trace the existing scrape behavior and tests, then verify that worker scrape timeouts and errors are represented by an exposed error counter without losing the existing scrape results.
Written by the indexing model from the issue text.
Assessment
- Tech stack
- javascript, nodejs
- Domain
- backend, observability
- Issue type
- Feature
- Difficulty
- 3/5
- Estimated time
- 1-2 days
- Activity status
- Active
- Clarity
- Mostly clear
- Newbie friendliness
- 68/100