Is there an easy way in Jenkins to list all all builds marked as keep-forever? And then, ideally, one click to either unmark the build as keep-forever or to immediately del
The following XPath query against Jenkins will list the URLs of all builds marked 'Keep Forever':
http://[jenkins_server]/api/xml?depth=2&xpath=/hudson/job/build[keepLog="true"]/url&wrapper=forever
Enter it in the browser and see what it returns.
Now, you can embed it into XSLT-based HTML to get a list with links to those builds. To delete the build you can provide a button that invokes Jenkins CLI:
java -jar jenkins-cli.jar -s http://[jenkins_server]/ delete-builds [job-name] [build-num]
Unfortunately, I do not know how to disable 'keep build forever' with CLI without deleting it.