#285 Add base class for ProxySQL tests

Proxy config population is still not working because I'm not able to
access the admin port on MacOS (via boot2docker). Moving development
into the cloud .. :)

test/proxysql_test.py

@@ -0,0 +1,82 @@
+import subprocess
+import time
+from unittest import TestCase
+
+from docker import Client
+from docker.utils import kwargs_from_env
+import MySQLdb
+
+class ProxySQLTest(TestCase):
+
+	DOCKER_COMPOSE_FILE = "./docker/1backend"
+
+	@classmethod
+	def _startup_docker_services(cls):
+		# We have to perform docker-compose build + docker-compose up,
+		# instead of just doing the latter because of a bug which will give a
+		# 500 internal error for the Docker bug. When this is fixed, we should
+		# remove this first extra step.
+		subprocess.call(["docker-compose", "build"], cwd=cls.DOCKER_COMPOSE_FILE)
+		subprocess.call(["docker-compose", "up", "-d"], cwd=cls.DOCKER_COMPOSE_FILE)
+
+	@classmethod
+	def _shutdown_docker_services(cls):
+		subprocess.call(["docker-compose", "stop"], cwd=cls.DOCKER_COMPOSE_FILE)
+		subprocess.call(["docker-compose", "rm", "--force"], cwd=cls.DOCKER_COMPOSE_FILE)
+
+	@classmethod
+	def _get_proxysql_container(cls):
+		containers = Client(**kwargs_from_env()).containers()
+		for container in containers:
+			if 'proxysql' in container['image']:
+				return container
+
+	@classmethod
+	def _get_mysql_containers(cls):
+		result = []
+		containers = Client(**kwargs_from_env()).containers()
+		for container in containers:
+			if 'proxysql' not in container['Image']:
+				result.append(container)
+		return result
+
+	@classmethod
+	def _populate_mysql_containers_with_dump(cls):
+		mysql_containers = cls._get_mysql_containers()
+		# We have already added the SQL dump to the container by using
+		# the ADD mysql command in the Dockerfile for mysql -- check it
+		# out. The standard agreed location is at /tmp/schema.sql.
+		#
+		# Unfortunately we can't do this step at runtime due to limitations
+		# on how transfer between host and container is supposed to work by
+		# design. See the Dockerfile for MySQL for more details.
+		for mysql_container in mysql_containers:
+			container_id = mysql_container['Names'][0][1:]
+			subprocess.call(["docker", "exec", container_id, "bash", "/tmp/import_schema.sh"])
+
+	@classmethod
+	def _populate_proxy_configuration_with_backends(cls):
+		pass
+
+	@classmethod
+	def setUpClass(cls):
+		cls._shutdown_docker_services()
+		cls._startup_docker_services()
+
+		# TODO(andrei): figure out a more reliable method to wait for
+		# MySQL to start up within the container. Otherwise, there will be
+		# an error when we try to initialize the MySQL instance with the dump.
+		time.sleep(30)
+		cls._populate_mysql_containers_with_dump()
+
+		cls._populate_proxy_configuration_with_backends()
+
+	@classmethod
+	def tearDownClass(cls):
+		pass
+
+	def test_asd(self):
+		self.assertEqual(1, 1)
+
+	def test_asdf(self):
+		self.assertEqual(1, 1)