What this PR does / why we need it:
Currently log level detection works only for a fixed set of default labels. The list in reality is unbounded, customers use any label or field such as log_level, logging_level, etc. There have been quite a few escalations and questions to Loki team concerning that it doesn't work properly when they something else apart from the default labels.
This PR adds an optional config to Loki that allows a tenant to specify custom labels for level detection.
The long term solution to this problem could be to leverage adaptive logs and patterns to make it robust. This is a temporary approach till we finalize on a better one.
[ ] Title matches the required conventional commits format, see here
Note that Promtail is considered to be feature complete, and future development for logs collection will be in Grafana Alloy. As such, feat PRs are unlikely to be accepted unless a case can be made for the feature actually being a bug fix to existing behavior.
[ ] Changes that require user attention or interaction to upgrade are documented in docs/sources/setup/upgrade/_index.md
[ ] If the change is deprecating or removing a configuration option, update the deprecated-config.yaml and deleted-config.yaml files respectively in the tools/deprecated-config-checker directory. Example PR
What this PR does / why we need it: Currently log level detection works only for a fixed set of default labels. The list in reality is unbounded, customers use any label or field such as log_level, logging_level, etc. There have been quite a few escalations and questions to Loki team concerning that it doesn't work properly when they something else apart from the default labels.
This PR adds an optional config to Loki that allows a tenant to specify custom labels for level detection.
The long term solution to this problem could be to leverage adaptive logs and patterns to make it robust. This is a temporary approach till we finalize on a better one.
Which issue(s) this PR fixes: Fixes #1194
Special notes for your reviewer:
Checklist
CONTRIBUTING.mdguide (required)featPRs are unlikely to be accepted unless a case can be made for the feature actually being a bug fix to existing behavior.docs/sources/setup/upgrade/_index.mddeprecated-config.yamlanddeleted-config.yamlfiles respectively in thetools/deprecated-config-checkerdirectory. Example PR