Add new db api method to get recent successes by metadata

This commit adds a new function to the DB API,
get_recent_successful_runs_by_run_metadata(), which is used to return
a list of recent Run objects for all runs with a provided key value
run_metadata pair.

Change-Id: Id6ca7e7a4cd1f913d9f84efae5f48d247dd9ed64

releasenotes/notes/add-recent-successful-runs-by-meta-560c35bcd21ac98e.yaml

@@ -0,0 +1,5 @@
+---
+features:
+  - A new DB API function, get_recent_successful_runs_by_run_metadata, was
+    added. This enabled returning a list of recent successful runs with a key
+    value run_metadata pair.

subunit2sql/db/api.py

@@ -1733,3 +1733,29 @@ def get_all_test_run_metadata_keys(session=None):
     session = session or get_session()
     keys = session.query(models.TestRunMetadata.key).distinct().all()
     return [key[0] for key in keys]
+
+
+def get_recent_successful_runs_by_run_metadata(key, value, num_runs=10,
+                                               start_date=None, session=None):
+    """Get a list of recent successful runs for a given run metadata pair
+
+    :param str key: The run_metadata key to get successful runs
+    :param str value: The run_metadata value to get successful runs
+    :param int num_runs: The number of results to fetch, defaults to 10
+    :param datetime start_date: The optional starting dates to get runs from.
+                                Nothing older than this date will be returned
+    :param session: Optional session object if one isn't provided a new session
+                    will be acquired for the duration of this operation
+
+    :return list: The list of recent failed Run objects
+    :rtype: subunit2sql.models.Run
+    """
+    session = session or get_session()
+    query = db_utils.model_query(models.Run, session).join(
+        models.RunMetadata, models.Run.id == models.RunMetadata.run_id).filter(
+            models.RunMetadata.key == key,
+            models.RunMetadata.value == value)
+    query = _filter_runs_by_date(query, start_date)
+    return query.filter(models.Run.passes >= 1).filter(
+        models.Run.fails == 0).order_by(
+            models.Run.run_at.desc()).limit(num_runs).all()

subunit2sql/tests/db/test_api.py

@@ -1149,3 +1149,29 @@ class TestDatabaseAPI(base.TestCase):
         self.assertIn((test_c.id,), res)
         self.assertIn((test_b.id,), res)
         self.assertIn((test_a.id,), res)
+
+    def test_get_recent_successful_runs_by_run_metadata_no_start_date(self):
+        run_a = api.create_run(fails=0, passes=1)
+        api.create_run()
+        run_c = api.create_run(fails=0, passes=2)
+        api.add_run_metadata({'fake_key': 'fake_value'}, run_a.id)
+        api.add_run_metadata({'zeon': 'zaku'}, run_c.id)
+        results = api.get_recent_successful_runs_by_run_metadata('zeon',
+                                                                 'zaku')
+        self.assertEqual(1, len(results))
+        self.assertEqual(run_c.id, results[0].id)
+
+    def test_get_recent_successful_runs_by_run_metadata_with_start_date(self):
+        run_a = api.create_run(fails=0, passes=1)
+        api.create_run()
+        run_c = api.create_run(fails=0, passes=2)
+        run_d = api.create_run(fails=0, passes=3,
+                               run_at=datetime.datetime(1914, 6, 28,
+                                                        10, 45, 0))
+        api.add_run_metadata({'fake_key': 'fake_value'}, run_a.id)
+        api.add_run_metadata({'zeon': 'zaku'}, run_c.id)
+        api.add_run_metadata({'zeon': 'zaku'}, run_d.id)
+        results = api.get_recent_successful_runs_by_run_metadata(
+            'zeon', 'zaku', start_date=datetime.date(1970, 1, 1))
+        self.assertEqual(1, len(results))
+        self.assertEqual(run_c.id, results[0].id)