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redis-py

The Python interface to the Redis key-value store.

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Installation | Usage | Advanced Topics | Contributing


Note: redis-py 5.0 is the last version of redis-py that supports Python 3.7, as it has reached end of life. redis-py 5.1 supports Python 3.8+.
Note: redis-py 6.1.0 is the last version of redis-py that supports Python 3.8, as it has reached end of life. redis-py 6.2.0 supports Python 3.9+.


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Installation

Start a redis via docker (for Redis versions >= 8.0):

docker run -p 6379:6379 -it redis:latest

Start a redis via docker (for Redis versions < 8.0):

docker run -p 6379:6379 -it redis/redis-stack:latest

To install redis-py, simply:

$ pip install redis

For faster performance, install redis with hiredis support, this provides a compiled response parser, and for most cases requires zero code changes. By default, if hiredis >= 1.0 is available, redis-py will attempt to use it for response parsing.

$ pip install "redis[hiredis]"

Looking for a high-level library to handle object mapping? See redis-om-python!

Supported Redis Versions

The most recent version of this library supports Redis version 7.2, 7.4, 8.0 and 8.2.

The table below highlights version compatibility of the most-recent library versions and redis versions.

Library version Supported redis versions
3.5.3 <= 6.2 Family of releases
>= 4.5.0 Version 5.0 to 7.0
>= 5.0.0 Version 5.0 to 7.4
>= 6.0.0 Version 7.2 to current

Usage

Basic Example

>>> import redis
>>> r = redis.Redis(host='localhost', port=6379, db=0)
>>> r.set('foo', 'bar')
True
>>> r.get('foo')
b'bar'

The above code connects to localhost on port 6379, sets a value in Redis, and retrieves it. All responses are returned as bytes in Python, to receive decoded strings, set decode_responses=True. For this, and more connection options, see these examples.

RESP3 Support

redis-py supports RESP3 starting with version 5.0. Starting with redis-py 8.0, clients use RESP3 on the wire by default while preserving legacy RESP2-compatible Python response shapes for existing applications.

Set protocol=3 explicitly when your application should receive RESP3-specific response shapes or when you want the wire protocol choice to be visible in code. To force RESP2 on the wire, set protocol=2. To opt in to protocol-independent response shapes, set legacy_responses=False.

For new projects, we recommend opting out of legacy response compatibility by setting legacy_responses=False. This makes redis-py return unified Python response shapes for affected commands whether the connection uses RESP2 or RESP3. Existing applications can keep the default legacy-compatible behavior while they migrate response handling at their own pace.

>>> import redis
>>> r = redis.Redis(host='localhost', port=6379, db=0, legacy_responses=False)

See the unified responses migration guide for activation instructions and command-by-command response differences. For RESP3-specific behavior, see the RESP3 features guide.

Connection Pools

By default, redis-py uses a connection pool to manage connections. Each instance of a Redis class receives its own connection pool. You can however define your own redis.ConnectionPool.

>>> pool = redis.ConnectionPool(host='localhost', port=6379, db=0)
>>> r = redis.Redis(connection_pool=pool)

Alternatively, you might want to look at Async connections, or Cluster connections, or even Async Cluster connections.

Redis Commands

There is built-in support for all of the out-of-the-box Redis commands. They are exposed using the raw Redis command names (HSET, HGETALL, etc.) except where a word (i.e. del) is reserved by the language. The complete set of commands can be found here, or the documentation.

Advanced Topics

The official Redis command documentation does a great job of explaining each command in detail. redis-py attempts to adhere to the official command syntax. There are a few exceptions:

For more details, please see the documentation on advanced topics page.

Pipelines

The following is a basic example of a Redis pipeline, a method to optimize round-trip calls, by batching Redis commands, and receiving their results as a list.

>>> pipe = r.pipeline()
>>> pipe.set('foo', 5)
>>> pipe.set('bar', 18.5)
>>> pipe.set('blee', "hello world!")
>>> pipe.execute()
[True, True, True]

PubSub

The following example shows how to utilize Redis Pub/Sub to subscribe to specific channels.

>>> r = redis.Redis(...)
>>> p = r.pubsub()
>>> p.subscribe('my-first-channel', 'my-second-channel', ...)
>>> p.get_message()
{'pattern': None, 'type': 'subscribe', 'channel': b'my-second-channel', 'data': 1}

Redis’ search and query capabilities default dialect

Release 6.0.0 introduces a client-side default dialect for Redis’ search and query capabilities. By default, the client now overrides the server-side dialect with version 2, automatically appending DIALECT 2 to commands like FT.AGGREGATE and FT.SEARCH.

Important: Be aware that the query dialect may impact the results returned. If needed, you can revert to a different dialect version by configuring the client accordingly.

>>> from redis.commands.search.field import TextField
>>> from redis.commands.search.query import Query
>>> from redis.commands.search.index_definition import IndexDefinition
>>> import redis

>>> r = redis.Redis(host='localhost', port=6379, db=0)
>>> r.ft().create_index(
>>>     (TextField("name"), TextField("lastname")),
>>>     definition=IndexDefinition(prefix=["test:"]),
>>> )

>>> r.hset("test:1", "name", "James")
>>> r.hset("test:1", "lastname", "Brown")

>>> # Query with default DIALECT 2
>>> query = "@name: James Brown"
>>> q = Query(query)
>>> res = r.ft().search(q)

>>> # Query with explicit DIALECT 1
>>> query = "@name: James Brown"
>>> q = Query(query).dialect(1)
>>> res = r.ft().search(q)

You can find further details in the query dialect documentation.

Multi-database client (Active-Active)

The multi-database client allows your application to connect to multiple Redis databases, which are typically replicas of each other. It is designed to work with Redis Software and Redis Cloud Active-Active setups. The client continuously monitors database health, detects failures, and automatically fails over to the next healthy database using a configurable strategy. When the original database becomes healthy again, the client can automatically switch back to it.
This is useful when:

  1. You have more than one Redis deployment. This might include two independent Redis servers or two or more Redis databases replicated across multiple active-active Redis Enterprise clusters.
  2. You want your application to connect to one deployment at a time and to fail over to the next available deployment if the first deployment becomes unavailable.

For the complete failover configuration options and examples, see the Multi-database client docs.


Author

redis-py is developed and maintained by Redis Inc. It can be found here, or downloaded from pypi.

Special thanks to:

Redis

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