Creates one database per sql test

A lot of sql tests are failing when running concurrently on the same
database. This patch drastically reduces the number of errors found
by creating one database for each test.

Related to blueprint sql-unit-tests-on-real-backend

Change-Id: I5a5f3a9f141c45a6c3c645e3b18089f442d29138

ceilometer/tests/db.py

@@ -28,6 +28,7 @@ from oslo.config import fixture as fixture_config
 from oslotest import mockpatch
 import six
 from six.moves.urllib import parse as urlparse
+import sqlalchemy
 import testscenarios.testcase
 from testtools import testcase
 
@@ -66,10 +67,6 @@ class MongoDbManager(fixtures.Fixture):
 
 
 class SQLManager(fixtures.Fixture):
-
-    def __init__(self, url):
-        self._url = url
-
     def setUp(self):
         super(SQLManager, self).setUp()
         self.connection = storage.get_connection(
@@ -81,7 +78,31 @@ class SQLManager(fixtures.Fixture):
 
     @property
     def url(self):
-        return self._url
+        return self._url.replace('template1', self._db_name)
+
+
+class PgSQLManager(SQLManager):
+
+    def __init__(self, url):
+        self._url = url
+        self._db_name = 'ceilometer_%s' % uuid.uuid4().hex
+        self._engine = sqlalchemy.create_engine(self._url)
+        self._conn = self._engine.connect()
+        self._conn.connection.set_isolation_level(0)
+        self._conn.execute(
+            'CREATE DATABASE %s WITH TEMPLATE template0;' % self._db_name)
+        self._conn.connection.set_isolation_level(1)
+
+
+class MySQLManager(SQLManager):
+
+    def __init__(self, url):
+        self._url = url
+        self._db_name = 'ceilometer_%s' % uuid.uuid4().hex
+        self._engine = sqlalchemy.create_engine(
+            self._url.replace('template1', ''))
+        self._conn = self._engine.connect()
+        self._conn.execute('CREATE DATABASE %s;' % self._db_name)
 
 
 class HBaseManager(fixtures.Fixture):
@@ -143,8 +164,8 @@ class TestBase(testscenarios.testcase.WithScenarios, test_base.BaseTestCase):
 
     DRIVER_MANAGERS = {
         'mongodb': MongoDbManager,
-        'mysql': SQLManager,
-        'postgresql': SQLManager,
+        'mysql': MySQLManager,
+        'postgresql': PgSQLManager,
         'db2': MongoDbManager,
         'sqlite': SQLiteManager,
         'hbase': HBaseManager,

setup-test-env-mysql.sh

@@ -22,9 +22,7 @@ mkfifo ${MYSQL_DATA}/out
 mysqld --datadir=${MYSQL_DATA} --pid-file=${MYSQL_DATA}/mysql.pid --socket=${MYSQL_DATA}/mysql.socket --skip-networking --skip-grant-tables &> ${MYSQL_DATA}/out &
 # Wait for MySQL to start listening to connections
 wait_for_line "mysqld: ready for connections." ${MYSQL_DATA}/out
-export CEILOMETER_TEST_MYSQL_URL="mysql://root@localhost/ceilometer?unix_socket=${MYSQL_DATA}/mysql.socket&charset=utf8"
-
-mysql -S ${MYSQL_DATA}/mysql.socket -e 'CREATE DATABASE ceilometer;'
+export CEILOMETER_TEST_MYSQL_URL="mysql://root@localhost/template1?unix_socket=${MYSQL_DATA}/mysql.socket&charset=utf8"
 
 # Yield execution to venv command
 $*