fix(mysql): add dialect parameter instead of hardcoded mysql dialect (testcontainers#739)

closes
testcontainers#727

* add parameter `dialect`;
* tests fixing and add some assertions

Author: nightblure

modules/mysql/testcontainers/mysql/__init__.py

@@ -31,14 +31,14 @@ class MySqlContainer(DbContainer):
         The example will spin up a MySql database to which you can connect with the credentials
         passed in the constructor. Alternatively, you may use the :code:`get_connection_url()`
         method which returns a sqlalchemy-compatible url in format
-        :code:`dialect+driver://username:password@host:port/database`.
+        :code:`mysql+dialect://username:password@host:port/database`.
 
         .. doctest::
 
             >>> import sqlalchemy
             >>> from testcontainers.mysql import MySqlContainer
 
-            >>> with MySqlContainer('mysql:5.7.17') as mysql:
+            >>> with MySqlContainer("mysql:5.7.17", dialect="pymysql") as mysql:
             ...     engine = sqlalchemy.create_engine(mysql.get_connection_url())
             ...     with engine.begin() as connection:
             ...         result = connection.execute(sqlalchemy.text("select version()"))
@@ -64,6 +64,7 @@ class MySqlContainer(DbContainer):
     def __init__(
         self,
         image: str = "mysql:latest",
+        dialect: Optional[str] = None,
         username: Optional[str] = None,
         root_password: Optional[str] = None,
         password: Optional[str] = None,
@@ -72,6 +73,10 @@ def __init__(
         seed: Optional[str] = None,
         **kwargs,
     ) -> None:
+        if dialect is not None and dialect.startswith("mysql+"):
+            msg = "Please remove 'mysql+' prefix from dialect parameter"
+            raise ValueError(msg)
+
         raise_for_deprecated_parameter(kwargs, "MYSQL_USER", "username")
         raise_for_deprecated_parameter(kwargs, "MYSQL_ROOT_PASSWORD", "root_password")
         raise_for_deprecated_parameter(kwargs, "MYSQL_PASSWORD", "password")
@@ -85,6 +90,9 @@ def __init__(
         self.password = password or environ.get("MYSQL_PASSWORD", "test")
         self.dbname = dbname or environ.get("MYSQL_DATABASE", "test")
 
+        self.dialect = dialect or environ.get("MYSQL_DIALECT", None)
+        self._db_url_dialect_part = "mysql" if self.dialect is None else f"mysql+{self.dialect}"
+
         if self.username == "root":
             self.root_password = self.password
         self.seed = seed
@@ -105,7 +113,11 @@ def _connect(self) -> None:
 
     def get_connection_url(self) -> str:
         return super()._create_connection_url(
-            dialect="mysql+pymysql", username=self.username, password=self.password, dbname=self.dbname, port=self.port
+            dialect=self._db_url_dialect_part,
+            username=self.username,
+            password=self.password,
+            dbname=self.dbname,
+            port=self.port,
         )
 
     def _transfer_seed(self) -> None:

modules/mysql/tests/test_mysql.py

@@ -11,9 +11,14 @@
 
 @pytest.mark.inside_docker_check
 def test_docker_run_mysql():
-    config = MySqlContainer("mysql:8.3.0")
+    config = MySqlContainer("mysql:8.3.0", dialect="pymysql")
     with config as mysql:
-        engine = sqlalchemy.create_engine(mysql.get_connection_url())
+        connection_url = mysql.get_connection_url()
+
+        assert mysql.dialect == "pymysql"
+        assert connection_url.startswith("mysql+pymysql://")
+
+        engine = sqlalchemy.create_engine(connection_url)
         with engine.begin() as connection:
             result = connection.execute(sqlalchemy.text("select version()"))
             for row in result:
@@ -22,7 +27,7 @@ def test_docker_run_mysql():
 
 @pytest.mark.skipif(is_arm(), reason="mysql container not available for ARM")
 def test_docker_run_legacy_mysql():
-    config = MySqlContainer("mysql:5.7.44")
+    config = MySqlContainer("mysql:5.7.44", dialect="pymysql")
     with config as mysql:
         engine = sqlalchemy.create_engine(mysql.get_connection_url())
         with engine.begin() as connection:
@@ -35,7 +40,7 @@ def test_docker_run_legacy_mysql():
 def test_docker_run_mysql_8_seed():
     # Avoid pytest CWD path issues
     SEEDS_PATH = (Path(__file__).parent / "seeds").absolute()
-    config = MySqlContainer("mysql:8", seed=SEEDS_PATH)
+    config = MySqlContainer("mysql:8", dialect="pymysql", seed=str(SEEDS_PATH))
     with config as mysql:
         engine = sqlalchemy.create_engine(mysql.get_connection_url())
         with engine.begin() as connection:
@@ -45,7 +50,7 @@ def test_docker_run_mysql_8_seed():
 
 @pytest.mark.parametrize("version", ["11.3.2", "10.11.7"])
 def test_docker_run_mariadb(version: str):
-    with MySqlContainer(f"mariadb:{version}") as mariadb:
+    with MySqlContainer(f"mariadb:{version}", dialect="pymysql") as mariadb:
         engine = sqlalchemy.create_engine(mariadb.get_connection_url())
         with engine.begin() as connection:
             result = connection.execute(sqlalchemy.text("select version()"))
@@ -55,14 +60,29 @@ def test_docker_run_mariadb(version: str):
 
 def test_docker_env_variables():
     with (
-        mock.patch.dict("os.environ", MYSQL_USER="demo", MYSQL_DATABASE="custom_db"),
+        mock.patch.dict("os.environ", MYSQL_DIALECT="pymysql", MYSQL_USER="demo", MYSQL_DATABASE="custom_db"),
         MySqlContainer("mariadb:10.6.5").with_bind_ports(3306, 32785) as container,
     ):
         url = container.get_connection_url()
         pattern = r"mysql\+pymysql:\/\/demo:test@[\w,.]+:(3306|32785)\/custom_db"
         assert re.match(pattern, url)
 
 
+@pytest.mark.parametrize(
+    "dialect",
+    [
+        "mysql+pymysql",
+        "mysql+mariadb",
+        "mysql+mysqldb",
+    ],
+)
+def test_mysql_dialect_expecting_error_on_mysql_prefix(dialect: str):
+    match = f"Please remove *.* prefix from dialect parameter"
+
+    with pytest.raises(ValueError, match=match):
+        _ = MySqlContainer("mariadb:10.6.5", dialect=dialect)
+
+
 # This is a feature in the generic DbContainer class
 # but it can't be tested on its own
 # so is tested in various database modules:
@@ -75,18 +95,18 @@ def test_quoted_password():
     user = "root"
     password = "p@$%25+0&%rd :/!=?"
     quoted_password = "p%40%24%2525+0%26%25rd %3A%2F%21%3D%3F"
-    driver = "pymysql"
-    with MySqlContainer("mariadb:10.6.5", username=user, password=password) as container:
+    dialect = "pymysql"
+    with MySqlContainer("mariadb:10.6.5", dialect=dialect, username=user, password=password) as container:
         host = container.get_container_host_ip()
         port = container.get_exposed_port(3306)
-        expected_url = f"mysql+{driver}://{user}:{quoted_password}@{host}:{port}/test"
+        expected_url = f"mysql+{dialect}://{user}:{quoted_password}@{host}:{port}/test"
         url = container.get_connection_url()
         assert url == expected_url
 
         with sqlalchemy.create_engine(expected_url).begin() as connection:
             connection.execute(sqlalchemy.text("select version()"))
 
-        raw_pass_url = f"mysql+{driver}://{user}:{password}@{host}:{port}/test"
+        raw_pass_url = f"mysql+{dialect}://{user}:{password}@{host}:{port}/test"
         with pytest.raises(Exception):
             with sqlalchemy.create_engine(raw_pass_url).begin() as connection:
                 connection.execute(sqlalchemy.text("select version()"))