Fix Gitlab trigger payload bug when commits is empty

Gitlab will occasionally send trigger payloads with an empty commit list (and a null checkout_ha) for branches that have been deleted. Properly handle that case.

buildtrigger/gitlabhandler.py

@@ -28,7 +28,7 @@ GITLAB_WEBHOOK_PAYLOAD_SCHEMA = {
       'type': 'string',
     },
     'checkout_sha': {
-      'type': 'string',
+      'type': ['string', 'null'],
     },
     'repository': {
       'type': 'object',
@@ -65,8 +65,7 @@ GITLAB_WEBHOOK_PAYLOAD_SCHEMA = {
         },
         'required': ['url', 'message', 'timestamp'],
       },
-      'minItems': 1,
+    },
-    }
   },
   'required': ['ref', 'checkout_sha', 'repository'],
 }
@@ -94,6 +93,11 @@ def get_transformed_webhook_payload(gl_payload, default_branch=None, lookup_user
 
   payload = JSONPathDict(gl_payload)
 
+  # Check for empty commits. The commits list will be empty if the branch is deleted.
+  commits = payload['commits']
+  if not commits:
+    raise SkipRequestException
+
   config = SafeDictSetter()
   config['commit'] = payload['checkout_sha']
   config['ref'] = payload['ref']

test/test_prepare_trigger.py

@@ -8,8 +8,20 @@ from buildtrigger.bitbuckethandler import get_transformed_webhook_payload as bb_
 from buildtrigger.bitbuckethandler import get_transformed_commit_info as bb_commit
 from buildtrigger.githubhandler import get_transformed_webhook_payload as gh_webhook
 from buildtrigger.gitlabhandler import get_transformed_webhook_payload as gl_webhook
+from buildtrigger.triggerutil import SkipRequestException
 
 class TestPrepareTrigger(unittest.TestCase):
+  def assertSkipped(self, filename, processor, *args, **kwargs):
+    with open('test/triggerjson/%s.json' % filename) as f:
+      payload = json.loads(f.read())
+
+    nargs = [payload]
+    nargs.extend(args)
+
+    with self.assertRaises(SkipRequestException):
+      processor(*nargs, **kwargs)
+
+
   def assertSchema(self, filename, expected, processor, *args, **kwargs):
     with open('test/triggerjson/%s.json' % filename) as f:
       payload = json.loads(f.read())
@@ -349,6 +361,9 @@ class TestPrepareTrigger(unittest.TestCase):
     self.assertSchema('github_webhook_missing', expected, gh_webhook)
 
 
+  def test_gitlab_webhook_nocommit_payload(self):
+    self.assertSkipped('gitlab_webhook_nocommit', gl_webhook)
+
   def test_gitlab_webhook_payload_with_lookup(self):
     expected = {
       'commit': u'fb88379ee45de28a0a4590fddcbd8eff8b36026e',

test/triggerjson/gitlab_webhook_nocommit.json

@@ -0,0 +1,44 @@
+{
+  "object_kind": "push",
+  "event_name": "push",
+  "before": "cc66287314cb154c986665a6c29377ef42edee60",
+  "after": "0000000000000000000000000000000000000000",
+  "ref": "refs\/heads\/foobar",
+  "checkout_sha": null,
+  "message": null,
+  "user_id": 750047,
+  "user_name": "Joseph Schorr",
+  "user_email": "joseph.schorr@coreos.com",
+  "user_avatar": "https:\/\/secure.gravatar.com\/avatar\/63e4521c07d2312d8e20c3a6cad36f57?s=80&d=identicon",
+  "project_id": 1756744,
+  "project": {
+    "name": "some-test-project",
+    "description": "",
+    "web_url": "https:\/\/gitlab.com\/joseph.schorr\/some-test-project",
+    "avatar_url": null,
+    "git_ssh_url": "git@gitlab.com:joseph.schorr\/some-test-project.git",
+    "git_http_url": "https:\/\/gitlab.com\/joseph.schorr\/some-test-project.git",
+    "namespace": "joseph.schorr",
+    "visibility_level": 0,
+    "path_with_namespace": "joseph.schorr\/some-test-project",
+    "default_branch": "master",
+    "homepage": "https:\/\/gitlab.com\/joseph.schorr\/some-test-project",
+    "url": "git@gitlab.com:joseph.schorr\/some-test-project.git",
+    "ssh_url": "git@gitlab.com:joseph.schorr\/some-test-project.git",
+    "http_url": "https:\/\/gitlab.com\/joseph.schorr\/some-test-project.git"
+  },
+  "commits": [
+
+  ],
+  "total_commits_count": 0,
+  "repository": {
+    "name": "some-test-project",
+    "url": "git@gitlab.com:joseph.schorr\/some-test-project.git",
+    "description": "",
+    "homepage": "https:\/\/gitlab.com\/joseph.schorr\/some-test-project",
+    "git_http_url": "https:\/\/gitlab.com\/joseph.schorr\/some-test-project.git",
+    "git_ssh_url": "git@gitlab.com:joseph.schorr\/some-test-project.git",
+    "visibility_level": 0
+  }
+}
+