Refactor action messaging to report on No Data state

[Zacqary]

Breaking Change Note

This causes a breakage in the beta feature of Metrics Alerting, and is therefore okay to release in 7.8.

Metrics alerts will no longer expose context.valueOf, context.metricOf, or context.thresholdOf to action messages. These are replaced by the variable context.reason, which explains the reason for the alert firing and automatically includes the metric, threshold, and current value of all configured conditions.

Any alerts configured in 7.7 will still function as normally, but their action messages may no longer provide useful information and have to be reconfigured. The new default action message will show an example of how to use context.reason.

Summary

Closes #64080

• Adds the context.alertState and context.reason values to action messages
  • alertState can be ALERT, NO DATA, or ERROR (Adding messaging for OK states will come in a later PR)
  • reason is a description of why the alertState was triggered: for ALERT it describes the current metric value(s) that have crossed a configured threshold, for NO DATA it lists metrics that haven't reported data, and for ERROR it lists metrics that could not be queried
• Adds a checkbox to enable or disable sending action messages on NO DATA/ERROR states. It is unchecked by default.
• Updates the default action message to reflect these changes

Note: Tooltip changed to "or if the alert fails to query Elasticsearch" in a commit after this screenshot was taken to better comply with EUI writing style

Checklist

• Any text added follows EUI's writing guidelines, uses sentence case text and includes i18n support
• Unit or functional tests were updated or added to match the most common scenarios

[elasticmachine]

Pinging @elastic/logs-metrics-ui (Team:logs-metrics-ui)

[Zacqary]

@elasticmachine merge upstream

[Zacqary]

Per discussion with @hbharding I pushed a change to the default action message from

Because {{context.reason}}

to

Reason:
{{context.reason}}

Each alert reason will now be separated by line breaks instead of semicolons (log messages convert line breaks to semicolons anyway)

[Zacqary]

@elasticmachine merge upstream

[Zacqary]

@elasticmachine merge upstream

[kibanamachine]

💚 Build Succeeded

• continuous-integration/kibana-ci/pull-request
• Commit: 909e6e0

History

• 💔 Build #43815 failed acf27e9
• 💔 Build #43566 failed 79488c4
• 💚 Build #43533 succeeded a4dba3a
• 💚 Build #43151 succeeded 5dfae65
• 💚 Build #43136 succeeded 782028d

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@elasticmachine merge upstream