Allow setting migrations timeout value from tox

The MIGRATIONS_TIMEOUT value is the timeout for the migrations tests
in seconds.
Can now be set ad environment variable, default to 60 seconds.

Change-Id: I20045a7c0c08a37038b4707791f6b67f715c4877

ironic/tests/unit/db/sqlalchemy/test_migrations.py

@@ -37,6 +37,7 @@ For postgres on Ubuntu this can be done with the following commands:
 import collections
 import contextlib
 import json
+import os
 from unittest import mock
 
 from alembic import script
@@ -61,7 +62,8 @@ LOG = logging.getLogger(__name__)
 
 # NOTE(vdrok): This was introduced after migration tests started taking more
 # time in gate. Timeout value in seconds for tests performing migrations.
-MIGRATIONS_TIMEOUT = 300
+# Can be modified in tox.ini as env variable.
+MIGRATIONS_TIMEOUT = os.getenv('MIGRATIONS_TIMEOUT', 60)
 
 
 @contextlib.contextmanager
@@ -188,8 +190,8 @@ class MigrationCheckersMixin(object):
         self.engine = enginefacade.writer.get_engine()
         self.config = migration._alembic_config()
         self.migration_api = migration
-        self.useFixture(fixtures.Timeout(MIGRATIONS_TIMEOUT,
-                                         gentle=True))
+        self.useFixture(fixtures.Timeout(int(MIGRATIONS_TIMEOUT),
+                                         gentle=False))
 
     def test_walk_versions(self):
         self._walk_versions(self.engine, self.config)
@@ -1439,8 +1441,8 @@ class ModelsMigrationSyncMixin(object):
     def setUp(self):
         super(ModelsMigrationSyncMixin, self).setUp()
         self.engine = enginefacade.writer.get_engine()
-        self.useFixture(fixtures.Timeout(MIGRATIONS_TIMEOUT,
-                                         gentle=True))
+        self.useFixture(fixtures.Timeout(int(MIGRATIONS_TIMEOUT),
+                                         gentle=False))
 
     def get_metadata(self):
         return models.Base.metadata

tox.ini

@@ -10,6 +10,7 @@ setenv = VIRTUAL_ENV={envdir}
          PYTHONDONTWRITEBYTECODE=1
          LANGUAGE=en_US
          LC_ALL=en_US.UTF-8
+         MIGRATIONS_TIMEOUT={env:MIGRATIONS_TIMEOUT:60}
          OS_LOG_CAPTURE={env:OS_LOG_CAPTURE:true}
          OS_STDOUT_CAPTURE={env:OS_STDOUT_CAPTURE:true}
          OS_STDERR_CAPTURE={env:OS_STDERR_CAPTURE:true}