Gitlab Merge request events not triggering Jenkins Multi-branch pipeline

Question

I'm trying to trigger Jenkins Multi-branch pipeline job with GitLab Webhook on Merge request events.

When I'm testing the Webhook, I'm getting this message:

Hook executed successfully but returned HTTP 409

When I'm setting different GitLab Webhook, like Tag push events, it works.

Is GitLab Merge request events Webhook not supported with Jenkins multi-branch pipeline? Am i missing something?

If it's not supported, does anyone have workaround for that?

Thanks!

Answer 1

https://github.com/jenkinsci/gitlab-plugin#git-configuration-for-multibranch-pipelineworkflow-jobs

Yeah, the readme notes that this functionality is not supported. Merge Events are just ignored as of now.

In this thread a user suggests some plugins that may add this support. I have not tried them myself and can not vouch.
https://github.com/jenkinsci/gitlab-plugin/issues/416