Merge "Fix issue in Github connection with large diffs"

tests/unit/test_github_driver.py

@@ -18,9 +18,10 @@ from testtools.matchers import MatchesRegex, StartsWith
 import urllib
 import socket
 import time
-from unittest import skip
+from unittest import mock, skip
 
 import git
+import github3.exceptions
 
 from tests.base import ZuulTestCase, simple_layout, random_sha1
 from tests.base import ZuulWebFixture
@@ -114,6 +115,19 @@ class TestGithubDriver(ZuulTestCase):
         self.waitUntilSettled()
         self.assertEqual(1, len(self.history))
 
+    @simple_layout('layouts/basic-github.yaml', driver='github')
+    def test_pull_github_files_error(self):
+        A = self.fake_github.openFakePullRequest(
+            'org/project', 'master', 'A')
+
+        with mock.patch("tests.fakegithub.FakePull.files") as files_mock:
+            files_mock.side_effect = github3.exceptions.ServerError(
+                mock.MagicMock())
+            self.fake_github.emitEvent(A.getPullRequestOpenedEvent())
+            self.waitUntilSettled()
+        self.assertEqual(1, files_mock.call_count)
+        self.assertEqual(2, len(self.history))
+
     @simple_layout('layouts/basic-github.yaml', driver='github')
     def test_comment_event(self):
         A = self.fake_github.openFakePullRequest('org/project', 'master', 'A')

zuul/driver/github/githubconnection.py

@@ -1044,7 +1044,16 @@ class GithubConnection(BaseConnection):
         # Get the issue obj so we can get the labels (this is silly)
         issueobj = probj.issue()
         pr = probj.as_dict()
-        pr['files'] = [f.filename for f in probj.files()]
+        try:
+            pr['files'] = [f.filename for f in probj.files()]
+        except github3.exceptions.ServerError as exc:
+            # NOTE: For PRs with a lot of lines changed, Github will return
+            # an error (HTTP 500) because it can't generate the diff.
+            self.log.warning("Failed to get list of files from Github. "
+                             "Using empty file list to trigger update "
+                             "via the merger: %s", exc)
+            pr['files'] = []
+
         pr['labels'] = [l.name for l in issueobj.labels()]
         self.log.debug('Got PR %s#%s', project_name, number)
         self.log_rate_limit(self.log, github)