A pytest plugin for tests that rely on a running MySQL or MariaDB database. It provides process and client fixtures.
Warning
Tested with MySQL 8.0+ and MariaDB 10.11+.
The plugin contains three fixtures:
- mysql - a function-scoped client fixture that drops the test database after each test to ensure repeatability.
- mysql_proc - a session-scoped process fixture that starts a local MySQL instance on first use and stops it at the end of the test session.
- mysql_noproc - a session-scoped fixture that connects to an already running MySQL instance.
Simply include one of these fixtures in your test fixture list.
You can also create additional MySQL client and process fixtures if you need to:
from pytest_mysql import factories from getpass import getuser mysql_my_proc = factories.mysql_proc( port=None, user=getuser()) mysql_my = factories.mysql('mysql_my_proc')
Note
Each MySQL process fixture can be configured in a different way than the others through the fixture factory arguments.
Install MySQL or MariaDB on the machine where tests are executed.
This plugin relies on binaries provided by those installations (for example mysqld and mysqladmin).
Use mysql_proc to start a local MySQL process from installed binaries.
Use mysql_noproc to connect to an already running MySQL/MariaDB server.
Install the plugin:
pip install pytest-mysql
Create a minimal test that uses the built-in fixture:
def test_mysql_fixture_available(mysql): assert mysql is not None
Run your tests:
pytest -q
You can define settings in three ways: fixture factory arguments, command-line options, and pytest.ini configuration options.
These settings are applied in the following order:
Fixture factory argumentCommand-line optionConfiguration option in your pytest.ini file
| MySQL/MariaDB option | Fixture factory argument | Command line option | pytest.ini option | Noproc process fixture | Default |
|---|---|---|---|---|---|
| Path to executable | mysqld_exec | --mysql-mysqld | mysql_mysqld | mysqld | |
| Path to safe executable | mysqld_safe | --mysql-mysqld-safe | mysql_mysqld_safe | mysqld_safe | |
| Path to mysql_install_db for legacy installations | install_db | --mysql-install-db | mysql_install_db | mysql_install_db | |
| Path to Admin executable | admin_executable | --mysql-admin | mysql_admin | mysqladmin | |
| Database hostname | host | --mysql-host | mysql_host | yes | localhost |
| Database port | port | --mysql-port | mysql_port | yes (3306) | random |
| Free port search count | port_search_count | --mysql-port-search-count | mysql_port_search_count | 5 | |
| MySQL user to work with | user | --mysql-user | mysql_user | root | |
| User's password | passwd | --mysql-passwd | mysql_passwd | ||
| Test database name | dbname | --mysql-dbname | mysql_dbname | test | |
| Starting parameters | params | --mysql-params | mysql_params |
Example usage:
pass it as an argument in your own fixture
mysql_proc = factories.mysql_proc( port=8888)
use
--mysql-portcommand line option when you run your testspytest tests --mysql-port=8888
specify your port as
mysql_portin yourpytest.inifileTo do so, put a line like the following under the
[pytest]section of yourpytest.ini:[pytest] mysql_port = 8888
The examples below show advanced integration patterns after your first smoke test is passing.
This example shows how to populate the database and create an SQLAlchemy ORM connection:
The sample below is a simplified session fixture from pyramid_fullauth tests:
from sqlalchemy import create_engine from sqlalchemy.orm import scoped_session, sessionmaker from sqlalchemy.pool import NullPool from zope.sqlalchemy import register @pytest.fixture def db_session(mysql): """Session for SQLAlchemy.""" from pyramid_fullauth.models import Base # pylint:disable=import-outside-toplevel # assumes setting, these can be obtained from pytest-mysql config or mysql_proc connection = f'mysql+mysqldb://root:@127.0.0.1:3307/tests?charset=utf8' engine = create_engine(connection, echo=False, poolclass=NullPool) pyramid_basemodel.Session = scoped_session(sessionmaker(extension=ZopeTransactionExtension())) pyramid_basemodel.bind_engine( engine, pyramid_basemodel.Session, should_create=True, should_drop=True) yield pyramid_basemodel.Session transaction.commit() Base.metadata.drop_all(engine) @pytest.fixture def user(db_session): """Test user fixture.""" from pyramid_fullauth.models import User from tests.tools import DEFAULT_USER new_user = User(**DEFAULT_USER) db_session.add(new_user) transaction.commit() return new_user def test_remove_last_admin(db_session, user): """ Sample test checks internal login, but shows usage in tests with SQLAlchemy """ user = db_session.merge(user) user.is_admin = True transaction.commit() user = db_session.merge(user) with pytest.raises(AttributeError): user.is_admin = False
Note
See the original code at pyramid_fullauth's conftest file. Depending on your needs, that in between code can fire alembic migrations in case of sqlalchemy stack or any other code
To connect to MySQL or MariaDB running in Docker, use noproc fixtures.
docker run --name some-db -e MYSQL_ALLOW_EMPTY_PASSWORD=yes -d mysql --expose 3306
docker run --name some-db -e MARIADB_ALLOW_EMPTY_PASSWORD=yes -d mariadb --expose 3306
This starts MySQL/MariaDB in a Docker container, but using a locally installed MySQL or MariaDB instance is similar.
In tests, make sure your tests use the mysql_noproc fixture like this:
mysql_in_docker = factories.mysql_noproc() mysql = factories.mysql("mysql_in_docker") def test_mysql_docker(mysql): """Run test.""" cur = mysql.cursor() cur.query("CREATE TABLE pet (name VARCHAR(20), owner VARCHAR(20), species VARCHAR(20), sex CHAR(1), birth DATE, death DATE);") mysql.commit() cur.close()
And run tests:
pytest --mysql-host=127.0.0.1
MySQL and MariaDB refuse to run as root by default, but we can force them by setting user=root in the configuration file.
However, the most common and secure approach is to change the user that runs tests in Docker:
USER nobody
This line should switch your Docker process to run as user nobody. See this comment for example.
- Bug tracker: https://github.com/dbfixtures/pytest-mysql/issues
Install pipenv and --dev dependencies first, then run:
pipenv run tbump [NEW_VERSION]