willholley opened a new pull request, #4475: URL: https://github.com/apache/couchdb/pull/4475
## Overview The `/_node/_local/_prometheus` is missing `# TYPE` annotations for some metrics. In addition, it contains no `# HELP` annotations, which are useful particularly where metrics do not strictly match those returned by the `_stats` or `_system` endpoints. This PR adds the missing `# TYPE` annotations and adds `# HELP` annotations to all metrics. The spec for the prometheus text format is at https://github.com/prometheus/docs/blob/main/content/docs/instrumenting/exposition_formats.md, for reference. ## couch_prometheus_util:to_prom/3 `couch_prometheus_util:to_prom/3` is replaced by `couch_prometheus_util:to_prom/4` which now expects a description alongside the metric name and type. ## couch_prometheus_util:couch_to_prom/3 `couch_prometheus_util:couch_to_prom/3` now extracts the metrics description from the object returned for each metric by `couch_stats`. In some cases, where the metrics are transformed e.g. from multiple metrics to a single metric with a tag, the description is explicitly changed to be more generic. ## Testing recommendations Unit tests are updated to expect the `# HELP` annotations alongside the `# TYPE` annotations for each metric. ## Related Issues or Pull Requests <!-- If your changes affect multiple components in different repositories please put links to those issues or pull requests here. --> ## Checklist - [ ] Code is written and works correctly - [ ] Changes are covered by tests - [ ] Any new configurable parameters are documented in `rel/overlay/etc/default.ini` - [ ] Documentation changes were made in the `src/docs` folder - [ ] Documentation changes were backported (separated PR) to affected branches -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
