Fix gitutils to use release-id

With the new release identification / naming schema [1] (like:
2023.1 Antelope) new stable branch naming was introduced (like:
stable/2023.1). This was not handled in check_branch_sha method
in validate.py, as the method still searches stable/$series.

This patch fixes this by reading the 'release-id' field from
series_status.yaml if present and uses it as stable/<release-id>
for the branch search.

[1] https://governance.openstack.org/tc/reference/release-naming.html

Change-Id: I014b1d6dc561be4db0fc8faa85fb3133e851acfc

openstack_releases/gitutils.py

@@ -19,6 +19,7 @@ import subprocess
 
 from openstack_releases import links
 from openstack_releases import processutils
+from openstack_releases import series_status
 
 # Disable warnings about insecure connections.
 from requests.packages import urllib3
@@ -29,6 +30,20 @@ LOG = logging.getLogger(__name__)
 GIT_TAG_TEMPLATE = 'https://opendev.org/%s/src/tag/%s'
 
 
+def get_stable_branch_id(series):
+    """Retrieve the stable branch ID of the series.
+
+    Returns the release-id if the series has such field, otherwise
+    returns the series name. This is needed for the new stable branch
+    naming style: stable/2023.1 (versus the old style: stable/zed).
+    """
+    series_status_data = series_status.SeriesStatus.default()
+    release_id = series_status_data[series].release_id
+    if release_id is None:
+        release_id = series
+    return str(release_id)
+
+
 def find_modified_deliverable_files():
     "Return a list of files modified by the most recent commit."
     results = processutils.check_output(
@@ -248,7 +263,7 @@ def check_branch_sha(workdir, repo, series, sha):
     if stable/N exists we could not create stable/N-1).
 
     """
-    remote_match = 'remotes/origin/stable/%s' % series
+    remote_match = 'remotes/origin/stable/%s' % get_stable_branch_id(series)
     try:
         containing_branches = _filter_branches(
             processutils.check_output(

openstack_releases/tests/test_validate.py

@@ -875,7 +875,11 @@ class TestValidateReleaseBranchMembership(base.BaseTestCase):
         self.assertEqual(0, len(self.ctx.warnings))
         self.assertEqual(0, len(self.ctx.errors))
 
-    def test_not_descendent(self):
+    @mock.patch('openstack_releases.gitutils.get_stable_branch_id')
+    def test_not_descendent(self, get_stable_branch_id):
+        get_stable_branch_id.configure_mock(
+            return_value='meiji',
+        )
         deliv = deliverable.Deliverable(
             team='team',
             series='meiji',