pytest-redis

What is this?

This is a pytest plugin that enables you to test your code that relies on a running Redis database. It allows you to specify additional fixtures for Redis process and client.

Quickstart: first test

1. Install the plugin and your test dependencies (as you normally do for your project).
2. Ensure Redis is available (local install or container). The redis-server executable must be on PATH, or pass it explicitly with --redis-exec. If Redis can't be found or started, pytest-redis raises RedisMisconfigured.
3. Create a test that uses the built-in fixture:

def test_can_connect(redisdb):
    redisdb.set("ping", "pong")
    assert redisdb.get("ping") == b"pong"

4. Run your tests:

pytest

The plugin contains four fixtures:

• redisdb - function-scoped client fixture that cleans all databases after each test.
• redisdb_async - function-scoped redis.asyncio client fixture, the asynchronous counterpart of redisdb. Requires the async extra, see Asynchronous Redis client.
• redis_proc - session-scoped fixture that starts Redis at first use and stops at the end of the tests.
• redis_noproc - no-process fixture that connects to an already running Redis instance.

Simply include one of these fixtures in your test fixture list.

How to use

#
def test_redis(redisdb):
    """Check that it's actually working on redis database."""
    redisdb.set('test1', 'test')
    redisdb.set('test2', 'test')

    my_functionality = MyRedisBasedComponent()
    my_functionality.do_something()
    assert my_functionality.did_something

    assert redisdb.get("did_it") == 1

The example above works as follows:

1. pytest runs tests
2. redis_proc starts redis database server
3. redisdb creates client connection to the server
4. test itself runs and finishes
5. redisdb cleans up the redis
6. redis_proc stops server (if that was the last test using it)
7. pytest ends running tests

You can also create additional redis client and process fixtures if you need to:

from pytest_redis import factories

redis_my_proc = factories.redis_proc(port=None)
redis_my = factories.redisdb('redis_my_proc')

def test_my_redis(redis_my):
    """Check that it's actually working on redis database."""
    redis_my.set('test1', 'test')
    redis_my.set('test2', 'test')

    my_functionality = MyRedisBasedComponent()
    my_functionality.do_something()
    assert my_functionality.did_something

    assert redis_my.get("did_it") == 1

Note

Each Redis process fixture can be configured in a different way than the others through the fixture factory arguments.

Asynchronous Redis client

redisdb_async is the asynchronous counterpart of redisdb. It yields a redis.asyncio.Redis client connected to the very same Redis instance the process fixtures manage, flushes all databases after each test and closes the client's connection pool on teardown.

It builds on pytest-asyncio, which is an optional dependency. Install it along with pytest-redis:

pip install 'pytest-redis[async]'

Then use the fixture from an async test:

import pytest

@pytest.mark.asyncio
async def test_redis_async(redisdb_async):
    """Check that it's actually working on redis database."""
    await redisdb_async.set('test1', 'test')

    assert await redisdb_async.get('test1') == b'test'

The redisdb_async factory takes the same arguments as redisdb, so additional async client fixtures are created the same way - including ones connecting to an already running server through redis_noproc:

from pytest_redis import factories

redis_my_proc = factories.redis_proc(port=None)
redis_my_async = factories.redisdb_async('redis_my_proc')
redis_external_async = factories.redisdb_async('redis_noproc')

Note

The process fixtures are shared between the sync and async client fixtures. redisdb and redisdb_async requested by the same test therefore talk to the same Redis instance.

Note

Without pytest-asyncio installed the fixture raises an ImportError pointing at the async extra, while the rest of pytest-redis keeps working as usual.

Connecting to already existing redis database

Some projects use already running Redis servers (i.e. on Docker instances). In order to connect to them, one would be using the redis_noproc fixture.

redis_external = factories.redisdb('redis_noproc')

def test_redis(redis_external):
    """Check that it's actually working on redis database."""
    redis_external.set('test1', 'test')
    redis_external.set('test2', 'test')

    my_functionality = MyRedisBasedComponent()
    my_functionality.do_something()
    assert my_functionality.did_something

    assert redis_external.get("did_it") == 1

Standard configuration options apply to it. Note that the modules configuration option has no effect with the redis_noproc fixture, it is the responsibility of the already running redis server to be properly started with extension modules, if needed.

By default the redis_noproc fixture would connect to Redis instance using 6379 port attempting to make a successful socket connection within 15 seconds. The fixture will block your test run within this timeout window. You can overwrite the timeout like so:

# set the blocking wait to 5 seconds
redis_noproc = factories.redis_noproc(startup_timeout=5)
redis_external = factories.redisdb('redis_noproc')

def test_redis(redis_external):
    """Check that it's actually working on redis database."""
    redis_external.set('test1', 'test')
    # etc etc

These are the configuration options that are working on all levels with the redis_noproc fixture:

Configuration

You can define your settings in three ways, it's fixture factory argument, command line option and pytest.ini configuration option. You can pick which you prefer, but remember that these settings are handled in the following order:

• Fixture factory argument
• Command line option
• Configuration option in your pytest.ini file

Configuration options

Redis server option	Fixture factory argument	Command line option	pytest.ini option	Noop process fixture	Default
executable	executable	--redis-exec	redis_exec		Look in PATH for redis-server via shutil.which
host	host	--redis-host	redis_host	host	127.0.0.1
port	port	--redis-port	redis_port	port	random
Free port search count	port_search_count	--redis-port-search-count	redis_port_search_count		5
username	username	--redis-username	redis_username	username	None
password	password	--redis-password	redis_password	password	None
connection timeout	timeout	--redis-timeout	redis_timeout		15
number of databases	db_count	--redis-db-count	redis_db_count		8
Whether to enable logging to the system logger	syslog	--redis-syslog	redis_syslog		False
Redis log verbosity level	loglevel	--redis-loglevel	redis_loglevel		notice
Compress dump files	compress	--redis-compress	redis_compress		True
Add checksum to RDB files	checksum	--redis-rdbcompress	redis_rdbchecksum		False
Save configuration	save	--redis-save	redis_save		""
Redis test instance data directory path	datadir	--redis-datadir	redis_datadir		""
Redis test instance extension module(s) path	modules (list of paths)	--redis-modules (comma-separated string)	redis_modules (comma-separated string)		""

Example usage:

• pass it as an argument in your own fixture

redis_proc = factories.redis_proc(port=8888)

• use --redis-port command line option when you run your tests

py.test tests --redis-port=8888

• specify your port as redis_port in your pytest.ini file.

  To do so, put a line like the following under the [pytest] section of your pytest.ini:

[pytest]
redis_port = 8888

Options below are for configuring redis client fixture.

Redis client option	Fixture factory argument	Command line option	pytest.ini option	Default
decode_response	decode	--redis-decode	redis_decode	False