builds: Fire Event if Build was triggered by clearing the last image ID

User Story

As an OpenShift cluster admin
I want to be alerted if something cleared the LastImageTriggeredID in a BuildConfig
So that I am aware that cluster users are relying on deprecated behavior.

Acceptance Criteria

• Cluster administrators can use system information to identify if a build was triggered by having the LastImagechangeTriggerID cleared
• Deprecation notice regarding this behavior is visible in the web console.

Launch Checklist

Dependencies identified
Blockers noted and expected delivery timelines set
Design is implementable
Acceptance criteria agreed upon
Story estimated

Notes

After review with the monitoring team, we agreed to use Warning events rather than alerts. To properly create an alert for this behavior, we would have needed to introduce a metric with unbound cardinality. Such metrics can lead to performance degradation in the cluster monitoring system.

When the LastImageChangeTriggerID is cleared in a BuildConfig object, a warning event is created which should appear in relevant contexts within the Web Console.

Guiding Questions

User Story

• Is this intended for an administrator, application developer, or other type of OpenShift user?
• What experience level is this intended for? New, experienced, etc.?
• Why is this story important? What problems does this solve? What benefit(s) will the customer experience?
• Is this part of a larger epic or initiative? If so, ensure that the story is linked to the appropriate epic and/or initiative.

Acceptance Criteria

• How should a customer use and/or configure the feature?
• Are there any prerequisites for using/enabling the feature?

Notes

• Is this a new feature, or an enhancement of an existing feature? If the latter, list the feature and docs reference.
• Are there any new terms, abbreviations, or commands introduced with this story? Ex: a new command line argument, a new custom resource.
• Are there any recommended best practices when using this feature?
• On feature completion, are there any known issues that customers should be aware of?