tests: Skip test for Pyro4 connection and added doc strings.

rhodecode/tests/vcs/test_hg_vcsserver_cache_invalidation.py

@@ -1,159 +1,189 b''
 # -*- coding: utf-8 -*-
 
 # Copyright (C) 2016-2016  RhodeCode GmbH
 #
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU Affero General Public License, version 3
 # (only), as published by the Free Software Foundation.
 #
 # This program is distributed in the hope that it will be useful,
 # but WITHOUT ANY WARRANTY; without even the implied warranty of
 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 # GNU General Public License for more details.
 #
 # You should have received a copy of the GNU Affero General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #
 # This program is dual-licensed. If you wish to learn more about the
 # RhodeCode Enterprise Edition, including its added features, Support services,
 # and proprietary license terms, please see https://rhodecode.com/licenses/
 
 import pytest
 
 from mock import call, patch
 
 from rhodecode.lib.vcs.backends.base import Reference
 
 
 class TestMercurialRemoteRepoInvalidation(object):
+    """
+    If the VCSServer is running with multiple processes or/and instances.
+    Operations on repositories are potentially handled by different processes
+    in a random fashion. The mercurial repository objects used in the VCSServer
+    are caching the commits of the repo. Therefore we have to invalidate the
+    VCSServer caching of these objects after a writing operation.
+    """
+
+    # Default reference used as a dummy during tests.
     default_ref = Reference('branch', 'default', None)
+
+    # Methods of vcsserver.hg.HgRemote that are "writing" operations.
     writing_methods = [
         'bookmark',
         'commit',
         'merge',
         'pull',
         'pull_cmd',
         'rebase',
         'strip',
         'tag',
     ]
 
     @pytest.mark.parametrize('method_name, method_args', [
         ('_local_merge', [default_ref, None, None, None, default_ref]),
         ('_local_pull', ['', default_ref]),
         ('bookmark', [None]),
         ('pull', ['', default_ref]),
         ('remove_tag', ['mytag', None]),
         ('strip', [None]),
         ('tag', ['newtag', None]),
     ])
     def test_method_invokes_invalidate_on_remote_repo(
             self, method_name, method_args, backend_hg):
         """
         Check that the listed methods are invalidating the VCSServer cache
         after invoking a writing method of their remote repository object.
         """
         tags = {'mytag': 'mytag-id'}
 
         def add_tag(name, raw_id, *args, **kwds):
             tags[name] = raw_id
 
         repo = backend_hg.repo.scm_instance()
         with patch.object(repo, '_remote') as remote:
             remote.lookup.return_value = ('commit-id', 'commit-idx')
             remote.tags.return_value = tags
             remote._get_tags.return_value = tags
             remote.tag.side_effect = add_tag
 
             # Invoke method.
             method = getattr(repo, method_name)
             method(*method_args)
 
             # Assert that every "writing" method is followed by an invocation
             # of the cache invalidation method.
             for counter, method_call in enumerate(remote.method_calls):
                 call_name = method_call[0]
                 if call_name in self.writing_methods:
                     next_call = remote.method_calls[counter + 1]
                     assert next_call == call.invalidate_vcs_cache()
 
     def _prepare_shadow_repo(self, pull_request):
         """
         Helper that creates a shadow repo that can be used to reproduce the
         CommitDoesNotExistError when pulling in from target and source
         references.
         """
         from rhodecode.model.pull_request import PullRequestModel
 
         target_vcs = pull_request.target_repo.scm_instance()
         target_ref = pull_request.target_ref_parts
         source_ref = pull_request.source_ref_parts
 
         # Create shadow repository.
         pr = PullRequestModel()
         workspace_id = pr._workspace_id(pull_request)
         shadow_repository_path = target_vcs._maybe_prepare_merge_workspace(
             workspace_id, target_ref)
         shadow_repo = target_vcs._get_shadow_instance(shadow_repository_path)
 
         # This will populate the cache of the mercurial repository object
         # inside of the VCSServer.
         shadow_repo.get_commit()
 
         return shadow_repo, source_ref, target_ref
 
     @pytest.mark.backends('hg')
-    def test_commit_does_not_exist_error_happens(self, pr_util):
+    def test_commit_does_not_exist_error_happens(self, pr_util, pylonsapp):
+        """
+        This test is somewhat special. It does not really test the system
+        instead it is more or less a precondition for the
+        "test_commit_does_not_exist_error_does_not_happen". It deactivates the
+        cache invalidation and asserts that the error occurs.
+        """
         from rhodecode.lib.vcs.exceptions import CommitDoesNotExistError
 
+        if pylonsapp.config['vcs.server.protocol'] != 'http':
+            pytest.skip('Test is intended for the HTTP protocol only.')
+
         pull_request = pr_util.create_pull_request()
         target_vcs = pull_request.target_repo.scm_instance()
         source_vcs = pull_request.source_repo.scm_instance()
         shadow_repo, source_ref, target_ref = self._prepare_shadow_repo(
             pull_request)
 
         # Pull from target and source references but without invalidation of
         # RemoteRepo objects and without VCSServer caching of mercurial
         # repository objects.
         with patch.object(shadow_repo._remote, 'invalidate_vcs_cache'):
             # NOTE: Do not use patch.dict() to disable the cache because it
             # restores the WHOLE dict and not only the patched keys.
             shadow_repo._remote._wire['cache'] = False
             shadow_repo._local_pull(target_vcs.path, target_ref)
             shadow_repo._local_pull(source_vcs.path, source_ref)
             shadow_repo._remote._wire.pop('cache')
 
         # Try to lookup the target_ref in shadow repo. This should work because
         # the shadow repo is a clone of the target and always contains all off
         # it's commits in the initial cache.
         shadow_repo.get_commit(target_ref.commit_id)
 
         # If we try to lookup the source_ref it should fail because the shadow
         # repo commit cache doesn't get invalidated. (Due to patched
         # invalidation and caching above).
         with pytest.raises(CommitDoesNotExistError):
             shadow_repo.get_commit(source_ref.commit_id)
 
     @pytest.mark.backends('hg')
-    def test_commit_does_not_exist_error_does_not_happen(self, pr_util):
+    def test_commit_does_not_exist_error_does_not_happen(
+            self, pr_util, pylonsapp):
+        """
+        This test simulates a pull request merge in which the pull operations
+        are handled by a different VCSServer process than all other operations.
+        Without correct cache invalidation this leads to an error when
+        retrieving the pulled commits afterwards.
+        """
+        if pylonsapp.config['vcs.server.protocol'] != 'http':
+            pytest.skip('Test is intended for the HTTP protocol only.')
+
         pull_request = pr_util.create_pull_request()
         target_vcs = pull_request.target_repo.scm_instance()
         source_vcs = pull_request.source_repo.scm_instance()
         shadow_repo, source_ref, target_ref = self._prepare_shadow_repo(
             pull_request)
 
         # Pull from target and source references without without VCSServer
         # caching of mercurial repository objects but with active invalidation
         # of RemoteRepo objects.
         # NOTE: Do not use patch.dict() to disable the cache because it
         # restores the WHOLE dict and not only the patched keys.
         shadow_repo._remote._wire['cache'] = False
         shadow_repo._local_pull(target_vcs.path, target_ref)
         shadow_repo._local_pull(source_vcs.path, source_ref)
         shadow_repo._remote._wire.pop('cache')
 
         # Try to lookup the target and source references in shadow repo. This
         # should work because the RemoteRepo object gets invalidated during the
         # above pull operations.
         shadow_repo.get_commit(target_ref.commit_id)
         shadow_repo.get_commit(source_ref.commit_id)