Allow running tests with multiple schedulers

The number of schedulers can be defined via the ZUUL_SCHEDULER_COUNT
environment variable (also forwarded by tox).

Disclaimer: running the tests with multiple schedulers will still fail
as not all test support multiple schedulers yet.

Change-Id: Ie11467dcf0fc36a5e167adcbd29ac4f256e0b3c5

tests/base.py

@@ -130,6 +130,7 @@ import tests.fakegitlab
 FIXTURE_DIR = os.path.join(os.path.dirname(__file__), 'fixtures')
 
 KEEP_TEMPDIRS = bool(os.environ.get('KEEP_TEMPDIRS', False))
+SCHEDULER_COUNT = int(os.environ.get('ZUUL_SCHEDULER_COUNT', 1))
 
 
 def repack_repo(path):
@@ -4488,6 +4489,7 @@ class ZuulTestCase(BaseTestCase):
     git_url_with_auth: bool = False
     log_console_port: int = 19885
     validate_tenants = None
+    scheduler_count = SCHEDULER_COUNT
 
     def __getattr__(self, name):
         """Allows to access fake connections the old way, e.g., using
@@ -4665,7 +4667,8 @@ class ZuulTestCase(BaseTestCase):
         self.builds = self.executor_server.running_builds
 
         self.scheds = SchedulerTestManager(self.validate_tenants)
-        self.createScheduler()
+        for _ in range(self.scheduler_count):
+            self.createScheduler()
 
         self.merge_server = None
 

tests/unit/test_configloader.py

@@ -954,6 +954,7 @@ class TestTenantExtra(TenantParserTestCase):
 
 class TestTenantDuplicate(TenantParserTestCase):
     tenant_config_file = 'config/tenant-parser/duplicate.yaml'
+    scheduler_count = 1
 
     def setUp(self):
         with testtools.ExpectedException(Exception, 'Duplicate configuration'):

tox.ini

@@ -28,6 +28,7 @@ passenv =
   YARN_REGISTRY
   ZUUL_MYSQL_HOST
   ZUUL_POSTGRES_HOST
+  ZUUL_SCHEDULER_COUNT
   ZUUL_TEST_ROOT
   ZUUL_ZK_HOST
   ZUUL_ZK_CA