How to prevent a GitLab CI/CD pipeline from running on tag events

How to prevent a GitLab CI/CD pipeline from running on tag events

According to the GitLab CI/CD documentation, a tag event in GitLab CI/CD is a push event (just like any other push of a commit on any branch), meaning that jobs will run for tag events unless $CI_PIPELINE_SOURCE = "push" is excluded in the rules section.

Now, in some scenarios—such as when we want to run both tag and release in the same pipeline—, a tag event should not trigger an additional pipeline run. Following this StackOverflow post, this is possible by excluding tag push events by checking if the CI_COMMIT_TAG variable has a non-empty value.

the_job:
	stage: the_stage
	script: 
		- echo "Doing my job."
		- ...
	rules:
		- if: '$CI_PIPELINE_SOURCE != "push" || $CI_COMMIT_TAG == null'
		  when: never