System hooks not working for latest Gitlab (version 9)

[bmaehr]

Issue

Gitlab has changed the structure of the webhook messages. The repository url is not detected anymore.

Context

• Gitlab-Hook plugin version: 1.4.6
• Gitlab version: 9.3.6
• Jenkins version: 2.69
• Job type: Freestyle

Logs & Traces

Problem description

Gitlab has changed the structure of the webhook messages:

Note: Starting from GitLab 8.5:

the repository key is deprecated in favor of the project key
the project.ssh_url key is deprecated in favor of the project.git_ssh_url key
the project.http_url key is deprecated in favor of the project.git_http_url key

https://docs.gitlab.com/ce/user/project/integrations/webhooks.html