georgemb Build tags? AFAIK tags are something static and this plugin is designed to build branches and PR, concepts that involve changes in our source code.

There needs to be a way to build a "release". The two obvious patterns are:

1. Somehow tell Jenkins this should be release and have it create a tag.
2. Have Jenkins detect that a tag was set and build it as a release (like Travis does).

With pipeline (aka Jenkinsfile) situation is much more worse: you can't checkout specified tag (parameters don't pass to branch specifier as environment variables).
But pipeline script (Jenkinsfile) loaded immediatly after checkout and you can't checkout right commit via Jenkinsfile and restart pipeline. So, I did not find correct solution for this situation.
For workaround my problem I use patched git-plugin (https://github.com/jenkinsci/git-plugin/pull/408).

recena Sorry that I missed your initial reply.

Tag building is around releases. Under almost every workflow of git, when someone creates a tag they are marking some sort of release. It would be great if Jenkins would know about this common work flow and do a build. Added logic to the build script could be added to perform extra actions when building a release.

Github has a releases page for every project. Integration of builds on tags could populate the releases tab with information/assets from the build.

Jenkin's has the ability to create tags on every build (useless), and the ability to create a tag on a particular build. The latter is sometimes useful, however under almost all circumstances is not adequate.

We also need the ability to tell jenkins to build a tag. Impossible with multibranch pipeline.

Currently i need to have 3 jobs of same application:
1. multibranch pipeline
2. single branch pipeline
3. singlebranch pipeline with custom groovy script

1 is for building all commits in all branches (running tests etc).
2 is for building and pushing docker image to registry
3 is to notify 2 to build specific commit (by selecting a tag using input

node('go'){
    
    stage 'Notify other job'
    def gitUrl = 'ssh://git@URL'

    git([url: gitUrl, branch: 'master', credentialsId: 'asdf'])

    sh('git show-ref --tags > tags')
    def tags = readFile('tags').trim()
    def userInput = input([ message: 'Please select git tag', parameters: [[$class: 'ChoiceParameterDefinition', choices: tags, description: '', name: 'Tag']]])

    echo ("selected tag: "+userInput)
    def sha1 = userInput.split(' ')[0]
    echo ("selected sha1: "+ sha1)
    
    sh("curl \"http://URL:8080/git/notifyCommit?url="+gitUrl+"&sha1="+sha1+"\"")
}

Why cant the multibranch job listen to notifyCommits with sha1?
Another solution is to fix the parameters so they could be sent to a multibranch pipeline script which then do git checkout based on tag.