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gitlab-org--gitlab-foss/doc/web_hooks/web_hooks.md
Jacob Vosmaer 5bd32954f6 Remove space
2016-05-09 13:52:20 +02:00

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Webhooks

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

Project webhooks allow you to trigger an URL if new code is pushed or a new issue is created.

You can configure webhooks to listen for specific events like pushes, issues or merge requests. GitLab will send a POST request with data to the webhook URL.

Webhooks can be used to update an external issue tracker, trigger CI builds, update a backup mirror, or even deploy to your production server.

Webhook endpoint tips

If you are writing your own endpoint (web server) that will receive GitLab webhooks keep in mind the following things:

  • Your endpoint should send its HTTP response as fast as possible. If you wait too long, GitLab may decide the hook failed and retry it.
  • Your endpoint should ALWAYS return a valid HTTP response. If you do not do this then GitLab will think the hook failed and retry it. Most HTTP libraries take care of this for you automatically but if you are writing a low-level hook this is important to remember.
  • GitLab ignores the HTTP status code returned by your endpoint.

SSL Verification

By default, the SSL certificate of the webhook endpoint is verified based on an internal list of Certificate Authorities, which means the certificate cannot be self-signed.

You can turn this off in the webhook settings in your GitLab projects.

SSL Verification

Push events

Triggered when you push to the repository except when pushing tags.

Request header:

X-Gitlab-Event: Push Hook

Request body:

{
  "object_kind": "push",
  "before": "95790bf891e76fee5e1747ab589903a6a1f80f22",
  "after": "da1560886d4f094c3e6c9ef40349f7d38b5d27d7",
  "ref": "refs/heads/master",
  "checkout_sha": "da1560886d4f094c3e6c9ef40349f7d38b5d27d7",
  "user_id": 4,
  "user_name": "John Smith",
  "user_email": "john@example.com",
  "user_avatar": "https://s.gravatar.com/avatar/d4c74594d841139328695756648b6bd6?s=8://s.gravatar.com/avatar/d4c74594d841139328695756648b6bd6?s=80",
  "project_id": 15,
  "project":{
    "name":"Diaspora",
    "description":"",
    "web_url":"http://example.com/mike/diaspora",
    "avatar_url":null,
    "git_ssh_url":"git@example.com:mike/diaspora.git",
    "git_http_url":"http://example.com/mike/diaspora.git",
    "namespace":"Mike",
    "visibility_level":0,
    "path_with_namespace":"mike/diaspora",
    "default_branch":"master",
    "homepage":"http://example.com/mike/diaspora",
    "url":"git@example.com:mike/diaspora.git",
    "ssh_url":"git@example.com:mike/diaspora.git",
    "http_url":"http://example.com/mike/diaspora.git"
  },
  "repository":{
    "name": "Diaspora",
    "url": "git@example.com:mike/diaspora.git",
    "description": "",
    "homepage": "http://example.com/mike/diaspora",
    "git_http_url":"http://example.com/mike/diaspora.git",
    "git_ssh_url":"git@example.com:mike/diaspora.git",
    "visibility_level":0
  },
  "commits": [
    {
      "id": "b6568db1bc1dcd7f8b4d5a946b0b91f9dacd7327",
      "message": "Update Catalan translation to e38cb41.",
      "timestamp": "2011-12-12T14:27:31+02:00",
      "url": "http://example.com/mike/diaspora/commit/b6568db1bc1dcd7f8b4d5a946b0b91f9dacd7327",
      "author": {
        "name": "Jordi Mallach",
        "email": "jordi@softcatala.org"
      },
      "added": ["CHANGELOG"],
      "modified": ["app/controller/application.rb"],
      "removed": []
    },
    {
      "id": "da1560886d4f094c3e6c9ef40349f7d38b5d27d7",
      "message": "fixed readme",
      "timestamp": "2012-01-03T23:36:29+02:00",
      "url": "http://example.com/mike/diaspora/commit/da1560886d4f094c3e6c9ef40349f7d38b5d27d7",
      "author": {
        "name": "GitLab dev user",
        "email": "gitlabdev@dv6700.(none)"
      },
      "added": ["CHANGELOG"],
      "modified": ["app/controller/application.rb"],
      "removed": []
    }
  ],
  "total_commits_count": 4
}

Tag events

Triggered when you create (or delete) tags to the repository.

Request header:

X-Gitlab-Event: Tag Push Hook

Request body:

{
  "object_kind": "tag_push",
  "before": "0000000000000000000000000000000000000000",
  "after": "82b3d5ae55f7080f1e6022629cdb57bfae7cccc7",
  "ref": "refs/tags/v1.0.0",
  "checkout_sha": "82b3d5ae55f7080f1e6022629cdb57bfae7cccc7",
  "user_id": 1,
  "user_name": "John Smith",
  "user_avatar": "https://s.gravatar.com/avatar/d4c74594d841139328695756648b6bd6?s=8://s.gravatar.com/avatar/d4c74594d841139328695756648b6bd6?s=80",
  "project_id": 1,
  "project":{
    "name":"Example",
    "description":"",
    "web_url":"http://example.com/jsmith/example",
    "avatar_url":null,
    "git_ssh_url":"git@example.com:jsmith/example.git",
    "git_http_url":"http://example.com/jsmith/example.git",
    "namespace":"Jsmith",
    "visibility_level":0,
    "path_with_namespace":"jsmith/example",
    "default_branch":"master",
    "homepage":"http://example.com/jsmith/example",
    "url":"git@example.com:jsmith/example.git",
    "ssh_url":"git@example.com:jsmith/example.git",
    "http_url":"http://example.com/jsmith/example.git"
  },
  "repository":{
    "name": "Example",
    "url": "ssh://git@example.com/jsmith/example.git",
    "description": "",
    "homepage": "http://example.com/jsmith/example",
    "git_http_url":"http://example.com/jsmith/example.git",
    "git_ssh_url":"git@example.com:jsmith/example.git",
    "visibility_level":0
  },
  "commits": [],
  "total_commits_count": 0
}

Issues events

Triggered when a new issue is created or an existing issue was updated/closed/reopened.

Request header:

X-Gitlab-Event: Issue Hook

Request body:

{
  "object_kind": "issue",
  "user": {
    "name": "Administrator",
    "username": "root",
    "avatar_url": "http://www.gravatar.com/avatar/e64c7d89f26bd1972efa854d13d7dd61?s=40\u0026d=identicon"
  },
  "project":{
    "name":"Gitlab Test",
    "description":"Aut reprehenderit ut est.",
    "web_url":"http://example.com/gitlabhq/gitlab-test",
    "avatar_url":null,
    "git_ssh_url":"git@example.com:gitlabhq/gitlab-test.git",
    "git_http_url":"http://example.com/gitlabhq/gitlab-test.git",
    "namespace":"GitlabHQ",
    "visibility_level":20,
    "path_with_namespace":"gitlabhq/gitlab-test",
    "default_branch":"master",
    "homepage":"http://example.com/gitlabhq/gitlab-test",
    "url":"http://example.com/gitlabhq/gitlab-test.git",
    "ssh_url":"git@example.com:gitlabhq/gitlab-test.git",
    "http_url":"http://example.com/gitlabhq/gitlab-test.git"
  },
  "repository":{
    "name": "Gitlab Test",
    "url": "http://example.com/gitlabhq/gitlab-test.git",
    "description": "Aut reprehenderit ut est.",
    "homepage": "http://example.com/gitlabhq/gitlab-test"
  },
  "object_attributes": {
    "id": 301,
    "title": "New API: create/update/delete file",
    "assignee_id": 51,
    "author_id": 51,
    "project_id": 14,
    "created_at": "2013-12-03T17:15:43Z",
    "updated_at": "2013-12-03T17:15:43Z",
    "position": 0,
    "branch_name": null,
    "description": "Create new API for manipulations with repository",
    "milestone_id": null,
    "state": "opened",
    "iid": 23,
    "url": "http://example.com/diaspora/issues/23",
    "action": "open"
  },
  "assignee": {
    "name": "User1",
    "username": "user1",
    "avatar_url": "http://www.gravatar.com/avatar/e64c7d89f26bd1972efa854d13d7dd61?s=40\u0026d=identicon"
  }
}

Comment events

Triggered when a new comment is made on commits, merge requests, issues, and code snippets. The note data will be stored in object_attributes (e.g. note, noteable_type). The payload will also include information about the target of the comment. For example, a comment on a issue will include the specific issue information under the issue key. Valid target types:

  1. commit
  2. merge_request
  3. issue
  4. snippet

Comment on commit

Request header:

X-Gitlab-Event: Note Hook

Request body:

{
  "object_kind": "note",
  "user": {
    "name": "Administrator",
    "username": "root",
    "avatar_url": "http://www.gravatar.com/avatar/e64c7d89f26bd1972efa854d13d7dd61?s=40\u0026d=identicon"
  },
  "project_id": 5,
  "project":{
    "name":"Gitlab Test",
    "description":"Aut reprehenderit ut est.",
    "web_url":"http://example.com/gitlabhq/gitlab-test",
    "avatar_url":null,
    "git_ssh_url":"git@example.com:gitlabhq/gitlab-test.git",
    "git_http_url":"http://example.com/gitlabhq/gitlab-test.git",
    "namespace":"GitlabHQ",
    "visibility_level":20,
    "path_with_namespace":"gitlabhq/gitlab-test",
    "default_branch":"master",
    "homepage":"http://example.com/gitlabhq/gitlab-test",
    "url":"http://example.com/gitlabhq/gitlab-test.git",
    "ssh_url":"git@example.com:gitlabhq/gitlab-test.git",
    "http_url":"http://example.com/gitlabhq/gitlab-test.git"
  },
  "repository":{
    "name": "Gitlab Test",
    "url": "http://example.com/gitlab-org/gitlab-test.git",
    "description": "Aut reprehenderit ut est.",
    "homepage": "http://example.com/gitlab-org/gitlab-test"
  },
  "object_attributes": {
    "id": 1243,
    "note": "This is a commit comment. How does this work?",
    "noteable_type": "Commit",
    "author_id": 1,
    "created_at": "2015-05-17 18:08:09 UTC",
    "updated_at": "2015-05-17 18:08:09 UTC",
    "project_id": 5,
    "attachment":null,
    "line_code": "bec9703f7a456cd2b4ab5fb3220ae016e3e394e3_0_1",
    "commit_id": "cfe32cf61b73a0d5e9f13e774abde7ff789b1660",
    "noteable_id": null,
    "system": false,
    "st_diff": {
      "diff": "--- /dev/null\n+++ b/six\n@@ -0,0 +1 @@\n+Subproject commit 409f37c4f05865e4fb208c771485f211a22c4c2d\n",
      "new_path": "six",
      "old_path": "six",
      "a_mode": "0",
      "b_mode": "160000",
      "new_file": true,
      "renamed_file": false,
      "deleted_file": false
    },
    "url": "http://example.com/gitlab-org/gitlab-test/commit/cfe32cf61b73a0d5e9f13e774abde7ff789b1660#note_1243"
  },
  "commit": {
    "id": "cfe32cf61b73a0d5e9f13e774abde7ff789b1660",
    "message": "Add submodule\n\nSigned-off-by: Dmitriy Zaporozhets \u003cdmitriy.zaporozhets@gmail.com\u003e\n",
    "timestamp": "2014-02-27T10:06:20+02:00",
    "url": "http://example.com/gitlab-org/gitlab-test/commit/cfe32cf61b73a0d5e9f13e774abde7ff789b1660",
    "author": {
      "name": "Dmitriy Zaporozhets",
      "email": "dmitriy.zaporozhets@gmail.com"
    }
  }
}

Comment on merge request

Request header:

X-Gitlab-Event: Note Hook

Request body:

{
  "object_kind": "note",
  "user": {
    "name": "Administrator",
    "username": "root",
    "avatar_url": "http://www.gravatar.com/avatar/e64c7d89f26bd1972efa854d13d7dd61?s=40\u0026d=identicon"
  },
  "project_id": 5,
  "project":{
    "name":"Gitlab Test",
    "description":"Aut reprehenderit ut est.",
    "web_url":"http://example.com/gitlab-org/gitlab-test",
    "avatar_url":null,
    "git_ssh_url":"git@example.com:gitlab-org/gitlab-test.git",
    "git_http_url":"http://example.com/gitlab-org/gitlab-test.git",
    "namespace":"Gitlab Org",
    "visibility_level":10,
    "path_with_namespace":"gitlab-org/gitlab-test",
    "default_branch":"master",
    "homepage":"http://example.com/gitlab-org/gitlab-test",
    "url":"http://example.com/gitlab-org/gitlab-test.git",
    "ssh_url":"git@example.com:gitlab-org/gitlab-test.git",
    "http_url":"http://example.com/gitlab-org/gitlab-test.git"
  },
  "repository":{
    "name": "Gitlab Test",
    "url": "http://localhost/gitlab-org/gitlab-test.git",
    "description": "Aut reprehenderit ut est.",
    "homepage": "http://example.com/gitlab-org/gitlab-test"
  },
  "object_attributes": {
    "id": 1244,
    "note": "This MR needs work.",
    "noteable_type": "MergeRequest",
    "author_id": 1,
    "created_at": "2015-05-17 18:21:36 UTC",
    "updated_at": "2015-05-17 18:21:36 UTC",
    "project_id": 5,
    "attachment": null,
    "line_code": null,
    "commit_id": "",
    "noteable_id": 7,
    "system": false,
    "st_diff": null,
    "url": "http://example.com/gitlab-org/gitlab-test/merge_requests/1#note_1244"
  },
  "merge_request": {
    "id": 7,
    "target_branch": "markdown",
    "source_branch": "master",
    "source_project_id": 5,
    "author_id": 8,
    "assignee_id": 28,
    "title": "Tempora et eos debitis quae laborum et.",
    "created_at": "2015-03-01 20:12:53 UTC",
    "updated_at": "2015-03-21 18:27:27 UTC",
    "milestone_id": 11,
    "state": "opened",
    "merge_status": "cannot_be_merged",
    "target_project_id": 5,
    "iid": 1,
    "description": "Et voluptas corrupti assumenda temporibus. Architecto cum animi eveniet amet asperiores. Vitae numquam voluptate est natus sit et ad id.",
    "position": 0,
    "locked_at": null,
    "source":{
      "name":"Gitlab Test",
      "description":"Aut reprehenderit ut est.",
      "web_url":"http://example.com/gitlab-org/gitlab-test",
      "avatar_url":null,
      "git_ssh_url":"git@example.com:gitlab-org/gitlab-test.git",
      "git_http_url":"http://example.com/gitlab-org/gitlab-test.git",
      "namespace":"Gitlab Org",
      "visibility_level":10,
      "path_with_namespace":"gitlab-org/gitlab-test",
      "default_branch":"master",
      "homepage":"http://example.com/gitlab-org/gitlab-test",
      "url":"http://example.com/gitlab-org/gitlab-test.git",
      "ssh_url":"git@example.com:gitlab-org/gitlab-test.git",
      "http_url":"http://example.com/gitlab-org/gitlab-test.git"
    },
    "target": {
      "name":"Gitlab Test",
      "description":"Aut reprehenderit ut est.",
      "web_url":"http://example.com/gitlab-org/gitlab-test",
      "avatar_url":null,
      "git_ssh_url":"git@example.com:gitlab-org/gitlab-test.git",
      "git_http_url":"http://example.com/gitlab-org/gitlab-test.git",
      "namespace":"Gitlab Org",
      "visibility_level":10,
      "path_with_namespace":"gitlab-org/gitlab-test",
      "default_branch":"master",
      "homepage":"http://example.com/gitlab-org/gitlab-test",
      "url":"http://example.com/gitlab-org/gitlab-test.git",
      "ssh_url":"git@example.com:gitlab-org/gitlab-test.git",
      "http_url":"http://example.com/gitlab-org/gitlab-test.git"
    },
    "last_commit": {
      "id": "562e173be03b8ff2efb05345d12df18815438a4b",
      "message": "Merge branch 'another-branch' into 'master'\n\nCheck in this test\n",
      "timestamp": "2015-04-08T21: 00:25-07:00",
      "url": "http://example.com/gitlab-org/gitlab-test/commit/562e173be03b8ff2efb05345d12df18815438a4b",
      "author": {
        "name": "John Smith",
        "email": "john@example.com"
      }
    },
    "work_in_progress": false,
    "assignee": {
      "name": "User1",
      "username": "user1",
      "avatar_url": "http://www.gravatar.com/avatar/e64c7d89f26bd1972efa854d13d7dd61?s=40\u0026d=identicon"
    }
  }
}

Comment on issue

Request header:

X-Gitlab-Event: Note Hook

Request body:

{
  "object_kind": "note",
  "user": {
    "name": "Administrator",
    "username": "root",
    "avatar_url": "http://www.gravatar.com/avatar/e64c7d89f26bd1972efa854d13d7dd61?s=40\u0026d=identicon"
  },
  "project_id": 5,
  "project":{
    "name":"Gitlab Test",
    "description":"Aut reprehenderit ut est.",
    "web_url":"http://example.com/gitlab-org/gitlab-test",
    "avatar_url":null,
    "git_ssh_url":"git@example.com:gitlab-org/gitlab-test.git",
    "git_http_url":"http://example.com/gitlab-org/gitlab-test.git",
    "namespace":"Gitlab Org",
    "visibility_level":10,
    "path_with_namespace":"gitlab-org/gitlab-test",
    "default_branch":"master",
    "homepage":"http://example.com/gitlab-org/gitlab-test",
    "url":"http://example.com/gitlab-org/gitlab-test.git",
    "ssh_url":"git@example.com:gitlab-org/gitlab-test.git",
    "http_url":"http://example.com/gitlab-org/gitlab-test.git"
  },
  "repository":{
    "name":"diaspora",
    "url":"git@example.com:mike/diaspora.git",
    "description":"",
    "homepage":"http://example.com/mike/diaspora"
  },
  "object_attributes": {
    "id": 1241,
    "note": "Hello world",
    "noteable_type": "Issue",
    "author_id": 1,
    "created_at": "2015-05-17 17:06:40 UTC",
    "updated_at": "2015-05-17 17:06:40 UTC",
    "project_id": 5,
    "attachment": null,
    "line_code": null,
    "commit_id": "",
    "noteable_id": 92,
    "system": false,
    "st_diff": null,
    "url": "http://example.com/gitlab-org/gitlab-test/issues/17#note_1241"
  },
  "issue": {
    "id": 92,
    "title": "test",
    "assignee_id": null,
    "author_id": 1,
    "project_id": 5,
    "created_at": "2015-04-12 14:53:17 UTC",
    "updated_at": "2015-04-26 08:28:42 UTC",
    "position": 0,
    "branch_name": null,
    "description": "test",
    "milestone_id": null,
    "state": "closed",
    "iid": 17
  }
}

Comment on code snippet

Request header:

X-Gitlab-Event: Note Hook

Request body:

{
  "object_kind": "note",
  "user": {
    "name": "Administrator",
    "username": "root",
    "avatar_url": "http://www.gravatar.com/avatar/e64c7d89f26bd1972efa854d13d7dd61?s=40\u0026d=identicon"
  },
  "project_id": 5,
  "project":{
    "name":"Gitlab Test",
    "description":"Aut reprehenderit ut est.",
    "web_url":"http://example.com/gitlab-org/gitlab-test",
    "avatar_url":null,
    "git_ssh_url":"git@example.com:gitlab-org/gitlab-test.git",
    "git_http_url":"http://example.com/gitlab-org/gitlab-test.git",
    "namespace":"Gitlab Org",
    "visibility_level":10,
    "path_with_namespace":"gitlab-org/gitlab-test",
    "default_branch":"master",
    "homepage":"http://example.com/gitlab-org/gitlab-test",
    "url":"http://example.com/gitlab-org/gitlab-test.git",
    "ssh_url":"git@example.com:gitlab-org/gitlab-test.git",
    "http_url":"http://example.com/gitlab-org/gitlab-test.git"
  },
  "repository":{
    "name":"Gitlab Test",
    "url":"http://example.com/gitlab-org/gitlab-test.git",
    "description":"Aut reprehenderit ut est.",
    "homepage":"http://example.com/gitlab-org/gitlab-test"
  },
  "object_attributes": {
    "id": 1245,
    "note": "Is this snippet doing what it's supposed to be doing?",
    "noteable_type": "Snippet",
    "author_id": 1,
    "created_at": "2015-05-17 18:35:50 UTC",
    "updated_at": "2015-05-17 18:35:50 UTC",
    "project_id": 5,
    "attachment": null,
    "line_code": null,
    "commit_id": "",
    "noteable_id": 53,
    "system": false,
    "st_diff": null,
    "url": "http://example.com/gitlab-org/gitlab-test/snippets/53#note_1245"
  },
  "snippet": {
    "id": 53,
    "title": "test",
    "content": "puts 'Hello world'",
    "author_id": 1,
    "project_id": 5,
    "created_at": "2015-04-09 02:40:38 UTC",
    "updated_at": "2015-04-09 02:40:38 UTC",
    "file_name": "test.rb",
    "expires_at": null,
    "type": "ProjectSnippet",
    "visibility_level": 0
  }
}

Merge request events

Triggered when a new merge request is created, an existing merge request was updated/merged/closed or a commit is added in the source branch.

Request header:

X-Gitlab-Event: Merge Request Hook

Request body:

{
  "object_kind": "merge_request",
  "user": {
    "name": "Administrator",
    "username": "root",
    "avatar_url": "http://www.gravatar.com/avatar/e64c7d89f26bd1972efa854d13d7dd61?s=40\u0026d=identicon"
  },
  "object_attributes": {
    "id": 99,
    "target_branch": "master",
    "source_branch": "ms-viewport",
    "source_project_id": 14,
    "author_id": 51,
    "assignee_id": 6,
    "title": "MS-Viewport",
    "created_at": "2013-12-03T17:23:34Z",
    "updated_at": "2013-12-03T17:23:34Z",
    "st_commits": null,
    "st_diffs": null,
    "milestone_id": null,
    "state": "opened",
    "merge_status": "unchecked",
    "target_project_id": 14,
    "iid": 1,
    "description": "",
    "source":{
      "name":"Awesome Project",
      "description":"Aut reprehenderit ut est.",
      "web_url":"http://example.com/awesome_space/awesome_project",
      "avatar_url":null,
      "git_ssh_url":"git@example.com:awesome_space/awesome_project.git",
      "git_http_url":"http://example.com/awesome_space/awesome_project.git",
      "namespace":"Awesome Space",
      "visibility_level":20,
      "path_with_namespace":"awesome_space/awesome_project",
      "default_branch":"master",
      "homepage":"http://example.com/awesome_space/awesome_project",
      "url":"http://example.com/awesome_space/awesome_project.git",
      "ssh_url":"git@example.com:awesome_space/awesome_project.git",
      "http_url":"http://example.com/awesome_space/awesome_project.git"
    },
    "target": {
      "name":"Awesome Project",
      "description":"Aut reprehenderit ut est.",
      "web_url":"http://example.com/awesome_space/awesome_project",
      "avatar_url":null,
      "git_ssh_url":"git@example.com:awesome_space/awesome_project.git",
      "git_http_url":"http://example.com/awesome_space/awesome_project.git",
      "namespace":"Awesome Space",
      "visibility_level":20,
      "path_with_namespace":"awesome_space/awesome_project",
      "default_branch":"master",
      "homepage":"http://example.com/awesome_space/awesome_project",
      "url":"http://example.com/awesome_space/awesome_project.git",
      "ssh_url":"git@example.com:awesome_space/awesome_project.git",
      "http_url":"http://example.com/awesome_space/awesome_project.git"
    },
    "last_commit": {
      "id": "da1560886d4f094c3e6c9ef40349f7d38b5d27d7",
      "message": "fixed readme",
      "timestamp": "2012-01-03T23:36:29+02:00",
      "url": "http://example.com/awesome_space/awesome_project/commits/da1560886d4f094c3e6c9ef40349f7d38b5d27d7",
      "author": {
        "name": "GitLab dev user",
        "email": "gitlabdev@dv6700.(none)"
      }
    },
    "work_in_progress": false,
    "url": "http://example.com/diaspora/merge_requests/1",
    "action": "open",
    "assignee": {
      "name": "User1",
      "username": "user1",
      "avatar_url": "http://www.gravatar.com/avatar/e64c7d89f26bd1972efa854d13d7dd61?s=40\u0026d=identicon"
    }
  }
}

Example webhook receiver

If you want to see GitLab's webhooks in action for testing purposes you can use a simple echo script running in a console session.

Save the following file as print_http_body.rb.

require 'webrick'

server = WEBrick::HTTPServer.new(:Port => ARGV.first)
server.mount_proc '/' do |req, res|
  puts req.body
end

trap 'INT' do
  server.shutdown
end
server.start

Pick an unused port (e.g. 8000) and start the script: ruby print_http_body.rb 8000. Then add your server as a webhook receiver in GitLab as http://my.host:8000/.

When you press 'Test Hook' in GitLab, you should see something like this in the console.

{"before":"077a85dd266e6f3573ef7e9ef8ce3343ad659c4e","after":"95cd4a99e93bc4bbabacfa2cd10e6725b1403c60",<SNIP>}
example.com - - [14/May/2014:07:45:26 EDT] "POST / HTTP/1.1" 200 0
- -> /