report_stages: surface a link from slave build to its master

BUG=chromium:496752
TEST=Unit tests enhanced to use fake_cidb, and use a master_build_id.
Verified that unit tests are exercising new code path.

Change-Id: I89497e449e29cc2c52474e37688891a086e29c48
Reviewed-on: https://chromium-review.googlesource.com/275314
Trybot-Ready: Aviv Keshet <akeshet@chromium.org>
Tested-by: Aviv Keshet <akeshet@chromium.org>
Reviewed-by: David James <davidjames@chromium.org>
Commit-Queue: Aviv Keshet <akeshet@chromium.org>

3 files changed, 29 insertions, 17 deletions

diff --git a/cbuildbot/stages/generic_stages_unittest.py b/cbuildbot/stages/generic_stages_unittest.py
index 42eafd359..435bd3442 100644
--- a/cbuildbot/stages/generic_stages_unittest.py
+++ b/cbuildbot/stages/generic_stages_unittest.py
@@ -73,7 +73,8 @@ class StageTestCase(cros_test_lib.MockOutputTestCase,
 
   def _Prepare(self, bot_id=None, extra_config=None, cmd_args=None,
                extra_cmd_args=None, build_id=DEFAULT_BUILD_ID,
-               waterfall=constants.WATERFALL_INTERNAL):
+               waterfall=constants.WATERFALL_INTERNAL,
+               master_build_id=None):
     """Prepare a BuilderRun at self._run for this test.
 
     This method must allow being called more than once.  Subclasses can
@@ -99,6 +100,7 @@ class StageTestCase(cros_test_lib.MockOutputTestCase,
         self._run.options.branch_name to be set to 'some-branch-name'.
       build_id: mock build id
       waterfall: One of constants.CIDB_KNOWN_WATERFALLS.
+      master_build_id: mock build id of master build.
     """
     # Use cbuildbot parser to create options object and populate default values.
     parser = cbuildbot._CreateParser()
@@ -151,6 +153,9 @@ class StageTestCase(cros_test_lib.MockOutputTestCase,
     if build_id is not None:
       self._run.attrs.metadata.UpdateWithDict({'build_id': build_id})
 
+    if master_build_id is not None:
+      self._run.options.master_build_id = master_build_id
+
     self._run.attrs.metadata.UpdateWithDict({'buildbot-master-name': waterfall})
 
     if self.RELEASE_TAG is not None:
diff --git a/cbuildbot/stages/report_stages.py b/cbuildbot/stages/report_stages.py
index ecd96d7c7..1d57d3ac6 100644
--- a/cbuildbot/stages/report_stages.py
+++ b/cbuildbot/stages/report_stages.py
@@ -163,6 +163,15 @@ class BuildStartStage(generic_stages.BuilderStage):
         logging.info('Inserted build_id %s into cidb database type %s.',
                      build_id, db_type)
 
+        master_build_id = d['master_build_id']
+        if master_build_id is not None:
+          master_build_status = db.GetBuildStatus(master_build_id)
+          master_url = tree_status.ConstructDashboardURL(
+              master_build_status['waterfall'],
+              master_build_status['builder_name'],
+              master_build_status['build_number'])
+          cros_build_lib.PrintBuildbotLink('Link to master build',
+                                           master_url)
 
   def HandleSkip(self):
     """Ensure that re-executions use the same db instance as initial db."""
diff --git a/cbuildbot/stages/report_stages_unittest.py b/cbuildbot/stages/report_stages_unittest.py
index 9729559b8..200d9a45b 100644
--- a/cbuildbot/stages/report_stages_unittest.py
+++ b/cbuildbot/stages/report_stages_unittest.py
@@ -66,7 +66,8 @@ class BuildReexecutionStageTest(generic_stages_unittest.AbstractStageTestCase):
     """Test that master/slave version mismatch causes failure."""
     master_release_tag = '9999.0.0-rc1'
     master_build_id = self.fake_db.InsertBuild(
-        'master', 'waterfall', 2, 'master config', 'master hostname')
+        'master', constants.WATERFALL_INTERNAL, 2, 'master config',
+        'master hostname')
     master_metadata = metadata_lib.CBuildbotMetadata()
     master_metadata.UpdateKeyDictWithDict(
         'version', {'full' : 'R39-9999.0.0-rc1',
@@ -87,11 +88,16 @@ class BuildStartStageTest(generic_stages_unittest.AbstractStageTestCase):
   """Tests that BuildStartStage behaves as expected."""
 
   def setUp(self):
-    self.mock_cidb = mock.MagicMock()
-    cidb.CIDBConnectionFactory.SetupMockCidb(self.mock_cidb)
+    self.db = fake_cidb.FakeCIDBConnection()
+    cidb.CIDBConnectionFactory.SetupMockCidb(self.db)
     retry_stats.SetupStats()
-    os.environ['BUILDBOT_MASTERNAME'] = 'chromiumos'
-    self._Prepare(build_id=None)
+    os.environ['BUILDBOT_MASTERNAME'] = constants.WATERFALL_EXTERNAL
+
+    master_build_id = self.db.InsertBuild(
+        'master_build', constants.WATERFALL_EXTERNAL, 1,
+        'master_build_config', 'bot_hostname')
+
+    self._Prepare(build_id=None, master_build_id=master_build_id)
 
   def testUnknownWaterfall(self):
     """Test that an assertion is thrown if master name is not valid."""
@@ -100,18 +106,10 @@ class BuildStartStageTest(generic_stages_unittest.AbstractStageTestCase):
 
   def testPerformStage(self):
     """Test that a normal run of the stage does a database insert."""
-    self.PatchObject(self.mock_cidb, 'InsertBuild', return_value=31337)
-
     self.RunStage()
-    self.mock_cidb.InsertBuild.assert_called_once_with(
-        bot_hostname=mock.ANY,
-        build_config='x86-generic-paladin',
-        build_number=1234321,
-        builder_name=mock.ANY,
-        master_build_id=None,
-        waterfall='chromiumos',
-        timeout_seconds=mock.ANY)
-    self.assertEqual(self._run.attrs.metadata.GetValue('build_id'), 31337)
+
+    build_id = self._run.attrs.metadata.GetValue('build_id')
+    self.assertGreater(build_id, 0)
     self.assertEqual(self._run.attrs.metadata.GetValue('db_type'),
                      cidb.CONNECTION_TYPE_MOCK)