* Migrate old alerting templates to use $labels
* Fix imports
* Add test coverage and separate rewriting to Go templates
* Fix lint
* Check for additional closing braces
* Add logging of invalid message templates
* Fix tests
* Small fixes
* Update comments
* Panic on empty token
* Use logtest.Fake
* Fix lint
* Allow for spaces in variable names by not tokenizing spaces
* Add template function to deduplicate Labels in a Value map
* Fix behavior of mapLookupString
* Reference deduplicated labels in migrated message template
* Fix behavior of deduplicateLabelsFunc
* Don't create variable for parent logger
* Add more tests for deduplicateLabelsFunc
* Remove unused function
* Apply suggestions from code review
Co-authored by: Yuri Tseretyan <yuriy.tseretyan@grafana.com>
* Give label val merge function better name
* Extract template migration and escape literal tokens
* Consolidate + simplify template migration
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Co-authored-by: William Wernert <william.wernert@grafana.com>
This commit adds filterLabels, filterLabelsRe, removeLabels, and
removeLabelsRe functions to templates for custom labels and annotations.
It allows for use cases such as removing all private labels.
This commit moves templating from the state package to a sub-package
called template. This sub-package will be the logical package for
future ease-of-use improvements to templating custom annotations
and labels.