promoted-image-governor

README

promoted-image-governor

What it does

promoted-image-governor is a tool with the following features:

• Delete the tags that are not promoted by any ci-operator' config on each integration image stream on app.ci and every build-farm cluster. An image stream is an integration image stream if it has a promoted tag.
• Generate the image mapping files for the quay.io/openshift organization.
• Explain why an imagestreamtag exists.

Why it exists

• Delete the stale images that were promoted in the past but are no more.
• Reduce the manual work on the maintenance of the mapping files and enforce their correctness.
• Save the effort of reversing engineering on which ci-operator's configuration promotes some image.

How it works

Regulate the image streams

• Collect all image streams with promoted tags
• Delete the tags if it meets none of the following criteria:
  • a promoted tag defined by a ci-operator's config
  • a mirrored tag by the release-controllers' config.
  • a tag matching the regular expression specified by --ignored-image-stream-tags flag

Maintain the mapping files

• Read the config file and the release-controllers' config
• Genenerate the mapping files

Explain

Looks for the ci-operator's configuration that promotes the image stream tag.

How is it deployed

The periodic job periodic-promoted-image-governor (definition) uses promoted-image-governor to regulate the image streams with promoted tags on every build-farm cluster.

The pre-submit job pull-ci-openshift-release-openshift-image-mirror-mappings (definition) uses promoted-image-governor to ensure the mapping files to be aligned with the output of the tool.

explain is a local utility:

$ istag=ocp/4.9:cli make explain
                 tag              explanation
         ocp/4.9:cli openshift/oc@release-4.9