aioredis

asyncio (PEP 3156) Redis client library.

The library is intended to provide simple and clear interface to Redis based on asyncio.

Features

hiredis parser Yes
Pure-python parser TBD
Low-level & High-level APIs Yes
Connections Pool Yes
Pipelining support Yes
Pub/Sub support Yes
Redis Cluster support WIP
Trollius (python 2.7) No
Tested python versions 3.3, 3.4, 3.5
Tested for Redis server 2.6, 2.8, 3.0, 3.2
Support for dev Redis server through low-level API

Installation

The easiest way to install aioredis is by using the package on PyPi:

pip install aioredis

Requirements

Contribute

Feel free to file an issue or make pull request if you find any bugs or have some suggestions for library improvement.

License

The aioredis is offered under MIT license.


Contents

Getting started

Commands Pipelining

Commands pipelining is built-in.

Every command is sent to transport at-once (ofcourse if no TypeError/ValueError was raised)

When you making a call with await / yield from you will be waiting result, and then gather results.

Simple example show both cases (get source code):

# No pipelining;
async def wait_each_command():
    val = await redis.get('foo')    # wait until `val` is available
    cnt = await redis.incr('bar')   # wait until `cnt` is available
    return val, cnt

# Sending multiple commands and then gathering results
async def pipelined():
    fut1 = redis.get('foo')      # issue command and return future
    fut2 = redis.incr('bar')     # issue command and return future
    # block until results are available
    val, cnt = await asyncio.gather(fut1, fut2)
    return val, cnt

Note

For convenience aioredis provides pipeline() method allowing to execute bulk of commands as one (get source code):

# Explicit pipeline
async def explicit_pipeline():
    pipe = redis.pipeline()
    fut1 = pipe.get('foo')
    fut2 = pipe.incr('bar')
    result = await pipe.execute()
    val, cnt = await asyncio.gather(fut1, fut2)
    assert result == [val, cnt]
    return val, cnt

Multi/Exec transactions

aioredis provides several ways for executing transactions:

  • when using raw connection you can issue Multi/Exec commands manually;
  • when using aioredis.Redis instance you can use multi_exec() transaction pipeline.

multi_exec() method creates and returns new MultiExec object which is used for buffering commands and then executing them inside MULTI/EXEC block.

Here is a simple example (get source code):

1
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5
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7
async def transaction():
    tr = redis.multi_exec()
    future1 = tr.set('foo', '123')
    future2 = tr.set('bar', '321')
    result = await tr.execute()
    assert result == await asyncio.gather(future1, future2)
    return result

As you can notice await is only used at line 5 with tr.execute and not with tr.set(...) calls.

Warning

It is very important not to await buffered command (ie tr.set('foo', '123')) as it will block forever.

The following code will block forever:

tr = redis.multi_exec()
await tr.incr('foo')   # that's all. we've stuck!

Pub/Sub mode

aioredis provides support for Redis Publish/Subscribe messaging.

To switch connection to subscribe mode you must execute subscribe command by yield’ing from subscribe() it returns a list of Channel objects representing subscribed channels.

As soon as connection is switched to subscribed mode the channel will receive and store messages (the Channel object is basically a wrapper around asyncio.Queue). To read messages from channel you need to use get() or get_json() coroutines.

Note

In Pub/Sub mode redis connection can only receive messages or issue (P)SUBSCRIBE / (P)UNSUBSCRIBE commands.

Pub/Sub example (get source code):

sub = await aioredis.create_redis(
     ('localhost', 6379))

ch1, ch2 = await sub.subscribe('channel:1', 'channel:2')
assert isinstance(ch1, aioredis.Channel)
assert isinstance(ch2, aioredis.Channel)

async def async_reader(channel):
    while await channel.wait_message():
        msg = await channel.get(encoding='utf-8')
        # ... process message ...
        print("message in {}: {}".format(channel.name, msg))

tsk1 = asyncio.ensure_future(async_reader(ch1))

# Or alternatively:

async def async_reader2(channel):
    while True:
        msg = await channel.get(encoding='utf-8')
        if msg is None:
            break
        # ... process message ...
        print("message in {}: {}".format(channel.name, msg))

tsk2 = asyncio.ensure_future(async_reader2(ch2))

Pub/Sub example (get source code):

async def reader(channel):
    while (await channel.wait_message()):
        msg = await channel.get(encoding='utf-8')
        # ... process message ...
        print("message in {}: {}".format(channel.name, msg))

        if msg == STOPWORD:
            return

with await pool as redis:
    channel, = await redis.subscribe('channel:1')
    await reader(channel)  # wait for reader to complete
    await redis.unsubscribe('channel:1')

# Explicit redis usage
redis = await pool.acquire()
try:
    channel, = await redis.subscribe('channel:1')
    await reader(channel)  # wait for reader to complete
    await redis.unsubscribe('channel:1')
finally:
    pool.release(redis)

Python 3.5 async with / async for support

aioredis is compatible with PEP 492.

Pool can be used with async with (get source code):

pool = await aioredis.create_pool(
    ('localhost', 6379))
async with pool.get() as conn:
    value = await conn.get('my-key')
    print('raw value:', value)

It also can be used with await:

pool = await aioredis.create_pool(
    ('localhost', 6379))
# This is exactly the same as:
#   with (yield from pool) as conn:
with await pool as conn:
    value = await conn.get('my-key')
    print('raw value:', value)

New scan-family commands added with support of async for (get source code):

redis = await aioredis.create_redis(
    ('localhost', 6379))

async for key in redis.iscan(match='something*'):
    print('Matched:', key)

async for name, val in redis.ihscan(key, match='something*'):
    print('Matched:', name, '->', val)

async for val in redis.isscan(key, match='something*'):
    print('Matched:', val)

async for val, score in redis.izscan(key, match='something*'):
    print('Matched:', val, ':', score)

SSL/TLS support

Though Redis server does not support data encryption it is still possible to setup Redis server behind SSL proxy. For such cases aioredis library support secure connections through asyncio SSL support. See BaseEventLoop.create_connection for details.

aioredis — API Reference

Connection

Redis Connection is the core function of the library. Connection instances can be used as is or through pool or high-level API.

Connection usage is as simple as:

import asyncio
import aioredis

async def connect_tcp():
    conn = await aioredis.create_connection(
        ('localhost', 6379))
    val = await conn.execute('GET', 'my-key')

async def connect_unixsocket():
    conn = await aioredis.create_connection(
        '/path/to/redis/socket')
    val = await conn.execute('GET', 'my-key')

asyncio.get_event_loop().run_until_complete(connect_tcp())
asyncio.get_event_loop().run_until_complete(connect_unixsocket())
coroutine aioredis.create_connection(address, *, db=0, password=None, ssl=None, encoding=None, loop=None)

Creates Redis connection.

Parameters:
  • address (tuple or str) – An address where to connect. Can be a (host, port) tuple or unix domain socket path string.
  • db (int) – Redis database index to switch to when connected.
  • password (str or None) – Password to use if redis server instance requires authorization.
  • ssl (ssl.SSLContext or True or None) – SSL context that is passed through to asyncio.BaseEventLoop.create_connection().
  • encoding (str or None) – Codec to use for response decoding.
  • loop (EventLoop) – An optional event loop instance (uses asyncio.get_event_loop() if not specified).
Returns:

RedisConnection instance.

class aioredis.RedisConnection

Bases: abc.AbcConnection

Redis connection interface.

address

Redis server address; either IP-port tuple or unix socket str (read-only). IP is either IPv4 or IPv6 depending on resolved host part in initial address.

New in version v0.2.8.

db

Current database index (read-only).

encoding

Current codec for response decoding (read-only).

closed

Set to True if connection is closed (read-only).

in_transaction

Set to True when MULTI command was issued (read-only).

pubsub_channels

Read-only dict with subscribed channels. Keys are bytes, values are Channel instances.

pubsub_patterns

Read-only dict with subscribed patterns. Keys are bytes, values are Channel instances.

in_pubsub

Indicates that connection is in PUB/SUB mode. Provides the number of subscribed channels. Read-only.

execute(command, *args, encoding=_NOTSET)

Execute Redis command.

The method is not a coroutine itself but instead it writes to underlying transport and returns a asyncio.Future waiting for result.

Parameters:
  • command (str, bytes, bytearray) – Command to execute
  • encoding (str or None) – Keyword-only argument for overriding response decoding. By default will use connection-wide encoding. May be set to None to skip response decoding.
Raises:
Returns:

Returns bytes or int reply (or str if encoding was set)

execute_pubsub(command, *channels_or_patterns)

Method to execute Pub/Sub commands. The method is not a coroutine itself but returns a asyncio.gather() coroutine. Method also accept aioredis.Channel instances as command arguments:

>>> ch1 = Channel('A', is_pattern=False, loop=loop)
>>> await conn.execute_pubsub('subscribe', ch1)
[[b'subscribe', b'A', 1]]

Changed in version v0.3: The method accept Channel instances.

Parameters:
  • command (str, bytes, bytearray) – One of the following Pub/Sub commands: subscribe, unsubscribe, psubscribe, punsubscribe.
  • *channels_or_patterns – Channels or patterns to subscribe connection to or unsubscribe from. At least one channel/pattern is required.
Returns:

Returns a list of subscribe/unsubscribe messages, ex:

>>> await conn.execute_pubsub('subscribe', 'A', 'B')
[[b'subscribe', b'A', 1], [b'subscribe', b'B', 2]]

close()

Closes connection.

Mark connection as closed and schedule cleanup procedure.

wait_closed()

Coroutine waiting for connection to get closed.

select(db)

Changes current db index to new one.

Parameters:

db (int) – New redis database index.

Raises:
Return True:

Always returns True or raises exception.

auth(password)

Send AUTH command.

Parameters:password (str) – Plain-text password
Return bool:True if redis replied with ‘OK’.

Connections Pool

The library provides connections pool. The basic usage is as follows:

import asyncio
import aioredis

async def sample_pool():
    pool = await aioredis.create_pool(('localhost', 6379))
    val = await pool.execute('get', 'my-key')
aioredis.create_pool(address, *, db=0, password=None, ssl=None, encoding=None, minsize=1, maxsize=10, commands_factory=_NOTSET, loop=None)

A coroutine that instantiates a pool of RedisConnection.

By default it creates pool of Redis instances, but it is also possible to create plain connections pool by passing lambda conn: conn as commands_factory.

Changed in version v0.2.7: minsize default value changed from 10 to 1.

Changed in version v0.2.8: Disallow arbitrary RedisPool maxsize.

Deprecated since version v0.2.9: commands_factory argument is deprecated and will be removed in v0.3.

Parameters:
  • address (tuple or str) – An address where to connect. Can be a (host, port) tuple or unix domain socket path string.
  • db (int) – Redis database index to switch to when connected.
  • password (str or None) – Password to use if redis server instance requires authorization.
  • ssl (ssl.SSLContext or True or None) – SSL context that is passed through to asyncio.BaseEventLoop.create_connection().
  • encoding (str or None) – Codec to use for response decoding.
  • minsize (int) – Minimum number of free connection to create in pool. 1 by default.
  • maxsize (int) – Maximum number of connection to keep in pool. 10 by default. Must be greater then 0. None is disallowed.
  • commands_factory (callable) – A factory to be passed to create_redis call. Redis by default. Deprecated since v0.2.8
  • loop (EventLoop) – An optional event loop instance (uses asyncio.get_event_loop() if not specified).
Returns:

RedisPool instance.

class aioredis.RedisPool

Redis connections pool.

minsize

A minimum size of the pool (read-only).

maxsize

A maximum size of the pool (read-only).

size

Current pool size — number of free and used connections (read-only).

freesize

Current number of free connections (read-only).

db

Currently selected db index (read-only).

encoding

Current codec for response decoding (read-only).

closed

True if pool is closed.

New in version v0.2.8.

coroutine clear()

Closes and removes all free connections in the pool.

coroutine select(db)

Changes db index for all free connections in the pool.

Parameters:db (int) – New database index.
coroutine acquire()

Acquires a connection from free pool. Creates new connection if needed.

Raises:aioredis.PoolClosedError – if pool is already closed
release(conn)

Returns used connection back into pool.

When returned connection has db index that differs from one in pool the connection will be dropped. When queue of free connections is full the connection will be dropped.

Note

This method is not a coroutine.

Parameters:conn (aioredis.RedisConnection) – A RedisConnection instance.
close()

Close all free and in-progress connections and mark pool as closed.

New in version v0.2.8.

coroutine wait_closed()

Wait until pool gets closed (when all connections are closed).

New in version v0.2.8.


Pub/Sub Channel object

Channel object is a wrapper around queue for storing received pub/sub messages.

class aioredis.Channel(name, is_pattern, loop=None)

Bases: abc.AbcChannel

Object representing Pub/Sub messages queue. It’s basically a wrapper around asyncio.Queue.

name

Holds encoded channel/pattern name.

is_pattern

Set to True for pattern channels.

is_active

Set to True if there are messages in queue and connection is still subscribed to this channel.

coroutine get(*, encoding=None, decoder=None)

Coroutine that waits for and returns a message.

Return value is message received or None signifying that channel has been unsubscribed and no more messages will be received.

Parameters:
  • encoding (str) – If not None used to decode resulting bytes message.
  • decoder (callable) – If specified used to decode message, ex. json.loads()
Raises:

aioredis.ChannelClosedError – If channel is unsubscribed and has no more messages.

get_json(*, encoding="utf-8")

Shortcut to get(encoding="utf-8", decoder=json.loads)

coroutine wait_message()

Waits for message to become available in channel.

Main idea is to use it in loops:

>>> ch = redis.channels['channel:1']
>>> while await ch.wait_message():
...     msg = await ch.get()
coroutine async-for iter()

Same as get() method but it is a native coroutine.

Usage example:

>>> async for msg in ch.iter():
...     print(msg)

New in version 0.2.5: Available for Python 3.5 only


Exceptions

exception aioredis.RedisError

Base exception class for aioredis exceptions.

exception aioredis.ProtocolError

Raised when protocol error occurs. When this type of exception is raised connection must be considered broken and must be closed.

exception aioredis.ReplyError

Raised for Redis error replies.

exception aioredis.ConnectionClosedError

Raised if connection to server was lost/closed.

exception aioredis.PipelineError

Raised from pipeline() if any pipelined command raised error.

exception aioredis.MultiExecError

Same as PipelineError but raised when executing multi_exec block.

exception aioredis.WatchVariableError

Raised if watched variable changed (EXEC returns None). Subclass of MultiExecError.

exception aioredis.ChannelClosedError

Raised from aioredis.Channel.get() when Pub/Sub channel is unsubscribed and messages queue is empty.

exception aioredis.PoolClosedError

Raised from aioredis.RedisPool.acquire() when pool is already closed.

Exceptions Hierarchy

Exception
   RedisError
      ProtocolError
      ReplyError
         PipelineError
            MultiExecError
               WatchVariableError
      ChannelClosedError
      ConnectionClosedError
      PoolClosedError

Commands Interface

The library provides high-level API implementing simple interface to Redis commands.

coroutine aioredis.create_redis(address, *, db=0, password=None, ssl=None, encoding=None, commands_factory=Redis, loop=None)

This coroutine creates high-level Redis interface instance.

Parameters:
  • address (tuple or str) – An address where to connect. Can be a (host, port) tuple or unix domain socket path string.
  • db (int) – Redis database index to switch to when connected.
  • password (str or None) – Password to use if redis server instance requires authorization.
  • ssl (ssl.SSLContext or True or None) – SSL context that is passed through to asyncio.BaseEventLoop.create_connection().
  • encoding (str or None) – Codec to use for response decoding.
  • commands_factory (callable) – A factory accepting single parameter – RedisConnection instance and returning an object providing high-level interface to Redis. Redis by default.
  • loop (EventLoop) – An optional event loop instance (uses asyncio.get_event_loop() if not specified).
coroutine aioredis.create_reconnecting_redis(address, *, db=0, password=None, ssl=None, encoding=None, commands_factory=Redis, loop=None)

Like create_redis() this coroutine creates high-level Redis interface instance that may reconnect to redis server between requests. Accepts same arguments as create_redis().

The reconnect process is done at most once, at the start of the request. So if your request is broken in the middle of sending or receiving reply, it will not be repeated but an exception is raised.

Note

There are two important differences between create_redis() and create_reconnecting_redis():

  1. The create_reconnecting_redis() does not establish connection “right now”, it defers connection establishing to the first request.
  2. Methods of Redis() factory returned do not buffer commands until you yield from it. I.e. they are real coroutines not the functions returning future. It may impact your pipelining.
class aioredis.Redis(connection)

High-level Redis commands interface.

For details see mixins reference.

aioredis.Redis — Commands Mixins Reference

This section contains reference for mixins implementing Redis commands.

Descriptions are taken from docstrings so may not contain proper markup.

class aioredis.Redis(connection)

High-level Redis interface.

Gathers in one place Redis commands implemented in mixins.

For commands details see: http://redis.io/commands/#connection

auth(password)

Authenticate to server.

This method wraps call to aioredis.RedisConnection.auth()

closed

True if connection is closed.

connection

aioredis.RedisConnection instance.

db

Currently selected db index.

echo(message, *, encoding=<object object>)

Echo the given string.

encoding

Current set codec or None.

in_transaction

Set to True when MULTI command was issued.

ping(*, encoding=<object object>)

Ping the server.

quit()

Close the connection.

select(db)

Change the selected database for the current connection.

This method wraps call to aioredis.RedisConnection.select()

Generic commands

class aioredis.commands.GenericCommandsMixin

Generic commands mixin.

For commands details see: http://redis.io/commands/#generic

delete(key, *keys)

Delete a key.

dump(key)

Dump a key.

exists(key, *keys)

Check if key(s) exists.

Changed in version v0.2.9: Accept multiple keys; return type changed from bool to int.

expire(key, timeout)

Set a timeout on key.

if timeout is float it will be multiplied by 1000 coerced to int and passed to pexpire method.

Otherwise raises TypeError if timeout argument is not int.

expireat(key, timestamp)

Set expire timestamp on key.

if timeout is float it will be multiplied by 1000 coerced to int and passed to pexpire method.

Otherwise raises TypeError if timestamp argument is not int.

keys(pattern, *, encoding=<object object>)

Returns all keys matching pattern.

migrate(host, port, key, dest_db, timeout, copy=False, replace=False)

Atomically transfer a key from a Redis instance to another one.

move(key, db)

Move key from currently selected database to specified destination.

Raises:
object_encoding(key)

Returns the kind of internal representation used in order to store the value associated with a key (OBJECT ENCODING).

object_idletime(key)

Returns the number of seconds since the object is not requested by read or write operations (OBJECT IDLETIME).

object_refcount(key)

Returns the number of references of the value associated with the specified key (OBJECT REFCOUNT).

persist(key)

Remove the existing timeout on key.

pexpire(key, timeout)

Set a milliseconds timeout on key.

Raises:TypeError – if timeout is not int
pexpireat(key, timestamp)

Set expire timestamp on key, timestamp in milliseconds.

Raises:TypeError – if timeout is not int
pttl(key)

Returns time-to-live for a key, in milliseconds.

Special return values (starting with Redis 2.8):

  • command returns -2 if the key does not exist.
  • command returns -1 if the key exists but has no associated expire.
randomkey(*, encoding=<object object>)

Return a random key from the currently selected database.

rename(key, newkey)

Renames key to newkey.

Raises:ValueError – if key == newkey
renamenx(key, newkey)

Renames key to newkey only if newkey does not exist.

Raises:ValueError – if key == newkey
restore(key, ttl, value)

Creates a key associated with a value that is obtained via DUMP.

scan(cursor=0, match=None, count=None)

Incrementally iterate the keys space.

Usage example:

>>> match = 'something*'
>>> cur = b'0'
>>> while cur:
...     cur, keys = await redis.scan(cur, match=match)
...     for key in keys:
...         print('Matched:', key)
sort(key, *get_patterns, by=None, offset=None, count=None, asc=None, alpha=False, store=None)

Sort the elements in a list, set or sorted set.

ttl(key)

Returns time-to-live for a key, in seconds.

Special return values (starting with Redis 2.8): * command returns -2 if the key does not exist. * command returns -1 if the key exists but has no associated expire.

type(key)

Returns the string representation of the value’s type stored at key.

Python 3.5 async/await support

class aioredis.commands.GenericCommandsMixin
async-for iscan(*, match=None, count=None)

Incrementally iterate the keys space using async for.

Usage example:

>>> async for key in redis.iscan(match='something*'):
...     print('Matched:', key)

See also GenericCommandsMixin.scan().

Geo commands

class aioredis.commands.GeoCommandsMixin

Geo commands mixin.

For commands details see: http://redis.io/commands#geo

geoadd(key, longitude, latitude, member, *args, **kwargs)

Add one or more geospatial items in the geospatial index represented using a sorted set.

geodist(key, member1, member2, unit='m')

Returns the distance between two members of a geospatial index.

Return type:list[float or None]
geohash(key, member, *args, **kwargs)

Returns members of a geospatial index as standard geohash strings.

geopos(key, member, *args, **kwargs)

Returns longitude and latitude of members of a geospatial index.

Return type:list[GeoPoint or None]
georadius(key, longitude, latitude, radius, unit='m', *, with_dist=False, with_hash=False, with_coord=False, count=None, sort=None, encoding=<object object>)

Query a sorted set representing a geospatial index to fetch members matching a given maximum distance from a point.

Return value follows Redis convention:

  • if none of WITH* flags are set – list of strings returned:

    >>> await redis.georadius('Sicily', 15, 37, 200, 'km')
    [b"Palermo", b"Catania"]
    
  • if any flag (or all) is set – list of named tuples returned:

    >>> await redis.georadius('Sicily', 15, 37, 200, 'km',
    ...                       with_dist=True)
    [GeoMember(name=b"Palermo", dist=190.4424, hash=None, coord=None),
     GeoMember(name=b"Catania", dist=56.4413, hash=None, coord=None)]
    
Raises:
Return type:

list[str] or list[GeoMember]

georadiusbymember(key, member, radius, unit='m', *, with_dist=False, with_hash=False, with_coord=False, count=None, sort=None, encoding=<object object>)

Query a sorted set representing a geospatial index to fetch members matching a given maximum distance from a member.

Return value follows Redis convention:

  • if none of WITH* flags are set – list of strings returned:

    >>> await redis.georadiusbymember('Sicily', 'Palermo', 200, 'km')
    [b"Palermo", b"Catania"]
    
  • if any flag (or all) is set – list of named tuples returned:

    >>> await redis.georadiusbymember('Sicily', 'Palermo', 200, 'km',
    ...                               with_dist=True)
    [GeoMember(name=b"Palermo", dist=190.4424, hash=None, coord=None),
     GeoMember(name=b"Catania", dist=56.4413, hash=None, coord=None)]
    
Raises:
Return type:

list[str] or list[GeoMember]

class aioredis.commands.GeoPoint(longitude, latitude)
class aioredis.commands.GeoMember(member, dist, hash, coord)

Strings commands

class aioredis.commands.StringCommandsMixin

String commands mixin.

For commands details see: http://redis.io/commands/#string

append(key, value)

Append a value to key.

bitcount(key, start=None, end=None)

Count set bits in a string.

Raises:TypeError – if only start or end specified.
bitop_and(dest, key, *keys)

Perform bitwise AND operations between strings.

bitop_not(dest, key)

Perform bitwise NOT operations between strings.

bitop_or(dest, key, *keys)

Perform bitwise OR operations between strings.

bitop_xor(dest, key, *keys)

Perform bitwise XOR operations between strings.

bitpos(key, bit, start=None, end=None)

Find first bit set or clear in a string.

Raises:ValueError – if bit is not 0 or 1
decr(key)

Decrement the integer value of a key by one.

decrby(key, decrement)

Decrement the integer value of a key by the given number.

Raises:TypeError – if decrement is not int
get(key, *, encoding=<object object>)

Get the value of a key.

getbit(key, offset)

Returns the bit value at offset in the string value stored at key.

Raises:
getrange(key, start, end, *, encoding=<object object>)

Get a substring of the string stored at a key.

Raises:TypeError – if start or end is not int
getset(key, value, *, encoding=<object object>)

Set the string value of a key and return its old value.

incr(key)

Increment the integer value of a key by one.

incrby(key, increment)

Increment the integer value of a key by the given amount.

Raises:TypeError – if increment is not int
incrbyfloat(key, increment)

Increment the float value of a key by the given amount.

Raises:TypeError – if increment is not int
mget(key, *keys, encoding=<object object>)

Get the values of all the given keys.

mset(key, value, *pairs)

Set multiple keys to multiple values.

Raises:TypeError – if len of pairs is not event number
msetnx(key, value, *pairs)

Set multiple keys to multiple values, only if none of the keys exist.

Raises:TypeError – if len of pairs is not event number
psetex(key, milliseconds, value)

Set the value and expiration in milliseconds of a key.

Raises:TypeError – if milliseconds is not int
set(key, value, *, expire=0, pexpire=0, exist=None)

Set the string value of a key.

Raises:TypeError – if expire or pexpire is not int
setbit(key, offset, value)

Sets or clears the bit at offset in the string value stored at key.

Raises:
  • TypeError – if offset is not int
  • ValueError – if offset is less then 0 or value is not 0 or 1
setex(key, seconds, value)

Set the value and expiration of a key.

If seconds is float it will be multiplied by 1000 coerced to int and passed to psetex method.

Raises:TypeError – if seconds is neither int nor float
setnx(key, value)

Set the value of a key, only if the key does not exist.

setrange(key, offset, value)

Overwrite part of a string at key starting at the specified offset.

Raises:
strlen(key)

Get the length of the value stored in a key.

Hash commands

class aioredis.commands.HashCommandsMixin

Hash commands mixin.

For commands details see: http://redis.io/commands#hash

hdel(key, field, *fields)

Delete one or more hash fields.

hexists(key, field)

Determine if hash field exists.

hget(key, field, *, encoding=<object object>)

Get the value of a hash field.

hgetall(key, *, encoding=<object object>)

Get all the fields and values in a hash.

hincrby(key, field, increment=1)

Increment the integer value of a hash field by the given number.

hincrbyfloat(key, field, increment=1.0)

Increment the float value of a hash field by the given number.

hkeys(key, *, encoding=<object object>)

Get all the fields in a hash.

hlen(key)

Get the number of fields in a hash.

hmget(key, field, *fields, encoding=<object object>)

Get the values of all the given fields.

hmset(key, field, value, *pairs)

Set multiple hash fields to multiple values.

hmset_dict(key, *args, **kwargs)

Set multiple hash fields to multiple values.

dict can be passed as first positional argument:

>>> await redis.hmset_dict(
...     'key', {'field1': 'value1', 'field2': 'value2'})

or keyword arguments can be used:

>>> await redis.hmset_dict(
...     'key', field1='value1', field2='value2')

or dict argument can be mixed with kwargs:

>>> await redis.hmset_dict(
...     'key', {'field1': 'value1'}, field2='value2')

Note

dict and kwargs not get mixed into single dictionary, if both specified and both have same key(s) – kwargs will win:

>>> await redis.hmset_dict('key', {'foo': 'bar'}, foo='baz')
>>> await redis.hget('key', 'foo', encoding='utf-8')
'baz'
hscan(key, cursor=0, match=None, count=None)

Incrementally iterate hash fields and associated values.

hset(key, field, value)

Set the string value of a hash field.

hsetnx(key, field, value)

Set the value of a hash field, only if the field does not exist.

hstrlen(key, field)

Get the length of the value of a hash field.

hvals(key, *, encoding=<object object>)

Get all the values in a hash.

Python 3.5 async/await support

class aioredis.commands.HashCommandsMixin
async-for ihscan(key, *, match=None, count=None)

Incrementally iterate sorted set items using async for.

Usage example:

>>> async for name, val in redis.ihscan(key, match='something*'):
...     print('Matched:', name, '->', val)

See also HashCommandsMixin.hscan().

List commands

class aioredis.commands.ListCommandsMixin

List commands mixin.

For commands details see: http://redis.io/commands#list

blpop(key, *keys, timeout=0, encoding=<object object>)

Remove and get the first element in a list, or block until one is available.

Raises:
brpop(key, *keys, timeout=0, encoding=<object object>)

Remove and get the last element in a list, or block until one is available.

Raises:
brpoplpush(sourcekey, destkey, timeout=0, encoding=<object object>)

Remove and get the last element in a list, or block until one is available.

Raises:
lindex(key, index, *, encoding=<object object>)

Get an element from a list by its index.

Raises:TypeError – if index is not int
linsert(key, pivot, value, before=False)

Inserts value in the list stored at key either before or after the reference value pivot.

llen(key)

Returns the length of the list stored at key.

lpop(key, *, encoding=<object object>)

Removes and returns the first element of the list stored at key.

lpush(key, value, *values)

Insert all the specified values at the head of the list stored at key.

lpushx(key, value)

Inserts value at the head of the list stored at key, only if key already exists and holds a list.

lrange(key, start, stop, *, encoding=<object object>)

Returns the specified elements of the list stored at key.

Raises:TypeError – if start or stop is not int
lrem(key, count, value)

Removes the first count occurrences of elements equal to value from the list stored at key.

Raises:TypeError – if count is not int
lset(key, index, value)

Sets the list element at index to value.

Raises:TypeError – if index is not int
ltrim(key, start, stop)

Trim an existing list so that it will contain only the specified range of elements specified.

Raises:TypeError – if start or stop is not int
rpop(key, *, encoding=<object object>)

Removes and returns the last element of the list stored at key.

rpoplpush(sourcekey, destkey, *, encoding=<object object>)

Atomically returns and removes the last element (tail) of the list stored at source, and pushes the element at the first element (head) of the list stored at destination.

rpush(key, value, *values)

Insert all the specified values at the tail of the list stored at key.

rpushx(key, value)

Inserts value at the tail of the list stored at key, only if key already exists and holds a list.

Set commands

class aioredis.commands.SetCommandsMixin

Set commands mixin.

For commands details see: http://redis.io/commands#set

sadd(key, member, *members)

Add one or more members to a set.

scard(key)

Get the number of members in a set.

sdiff(key, *keys)

Subtract multiple sets.

sdiffstore(destkey, key, *keys)

Subtract multiple sets and store the resulting set in a key.

sinter(key, *keys)

Intersect multiple sets.

sinterstore(destkey, key, *keys)

Intersect multiple sets and store the resulting set in a key.

sismember(key, member)

Determine if a given value is a member of a set.

smembers(key, *, encoding=<object object>)

Get all the members in a set.

smove(sourcekey, destkey, member)

Move a member from one set to another.

spop(key, *, encoding=<object object>)

Remove and return a random member from a set.

srandmember(key, count=None, *, encoding=<object object>)

Get one or multiple random members from a set.

srem(key, member, *members)

Remove one or more members from a set.

sscan(key, cursor=0, match=None, count=None)

Incrementally iterate Set elements.

sunion(key, *keys)

Add multiple sets.

sunionstore(destkey, key, *keys)

Add multiple sets and store the resulting set in a key.

Python 3.5 async/await support

class aioredis.commands.SetCommandsMixin
async-for isscan(key, *, match=None, count=None)

Incrementally iterate set elements using async for.

Usage example:

>>> async for val in redis.isscan(key, match='something*'):
...     print('Matched:', val)

See also SetCommandsMixin.sscan().

Sorted Set commands

class aioredis.commands.SortedSetCommandsMixin

Sorted Sets commands mixin.

For commands details see: http://redis.io/commands/#sorted_set

zadd(key, score, member, *pairs)

Add one or more members to a sorted set or update its score.

Raises:
zcard(key)

Get the number of members in a sorted set.

zcount(key, min=-inf, max=inf, *, exclude=None)

Count the members in a sorted set with scores within the given values.

Raises:
zincrby(key, increment, member)

Increment the score of a member in a sorted set.

Raises:TypeError – increment is not float or int
zinterstore(destkey, key, *keys, with_weights=False, aggregate=None)

Intersect multiple sorted sets and store result in a new key.

Parameters:with_weights (bool) – when set to true each key must be a tuple in form of (key, weight)
zlexcount(key, min=b'-', max=b'+', include_min=True, include_max=True)

Count the number of members in a sorted set between a given lexicographical range.

Raises:
zrange(key, start=0, stop=-1, withscores=False)

Return a range of members in a sorted set, by index.

Raises:
zrangebylex(key, min=b'-', max=b'+', include_min=True, include_max=True, offset=None, count=None)

Return a range of members in a sorted set, by lexicographical range.

Raises:
zrangebyscore(key, min=-inf, max=inf, withscores=False, offset=None, count=None, *, exclude=None)

Return a range of members in a sorted set, by score.

Raises:
zrank(key, member)

Determine the index of a member in a sorted set.

zrem(key, member, *members)

Remove one or more members from a sorted set.

zremrangebylex(key, min=b'-', max=b'+', include_min=True, include_max=True)

Remove all members in a sorted set between the given lexicographical range.

Raises:
zremrangebyrank(key, start, stop)

Remove all members in a sorted set within the given indexes.

Raises:
zremrangebyscore(key, min=-inf, max=inf, *, exclude=None)

Remove all members in a sorted set within the given scores.

Raises:TypeError – if min or max is not int or float
zrevrange(key, start, stop, withscores=False)

Return a range of members in a sorted set, by index, with scores ordered from high to low.

Raises:TypeError – if start or stop is not int
zrevrangebyscore(key, max=inf, min=-inf, *, exclude=None, withscores=False, offset=None, count=None)

Return a range of members in a sorted set, by score, with scores ordered from high to low.

Raises:
zrevrank(key, member)

Determine the index of a member in a sorted set, with scores ordered from high to low.

zscan(key, cursor=0, match=None, count=None)

Incrementally iterate sorted sets elements and associated scores.

zscore(key, member)

Get the score associated with the given member in a sorted set.

zunionstore(destkey, key, *keys, with_weights=False, aggregate=None)

Add multiple sorted sets and store result in a new key.

Python 3.5 async/await support

class aioredis.commands.SortedSetCommandsMixin
async-for izscan(key, *, match=None, count=None)

Incrementally iterate sorted set items using async for.

Usage example:

>>> async for val, score in redis.izscan(key, match='something*'):
...     print('Matched:', val, ':', score)

See also SortedSetCommandsMixin.zscan().

Server commands

class aioredis.commands.ServerCommandsMixin

Server commands mixin.

For commands details see: http://redis.io/commands/#server

bgrewriteaof()

Asynchronously rewrite the append-only file.

bgsave()

Asynchronously save the dataset to disk.

client_getname(encoding=<object object>)

Get the current connection name.

client_kill()

Kill the connection of a client.

Warning

Not Implemented

client_list()

Get the list of client connections.

Returns list of ClientInfo named tuples.

client_pause(timeout)

Stop processing commands from clients for timeout milliseconds.

Raises:
client_setname(name)

Set the current connection name.

config_get(parameter='*')

Get the value of a configuration parameter(s).

If called without argument will return all parameters.

Raises:TypeError – if parameter is not string
config_resetstat()

Reset the stats returned by INFO.

config_rewrite()

Rewrite the configuration file with the in memory configuration.

config_set(parameter, value)

Set a configuration parameter to the given value.

dbsize()

Return the number of keys in the selected database.

debug_object(key)

Get debugging information about a key.

debug_segfault(key)

Make the server crash.

flushall()

Remove all keys from all databases.

flushdb()

Remove all keys from the current database.

info(section='default')

Get information and statistics about the server.

If called without argument will return default set of sections. For available sections, see http://redis.io/commands/INFO

Raises:ValueError – if section is invalid
lastsave()

Get the UNIX time stamp of the last successful save to disk.

monitor()

Listen for all requests received by the server in real time.

Warning

Will not be implemented for now.

role()

Return the role of the server instance.

Returns named tuples describing role of the instance. For fields information see http://redis.io/commands/role#output-format

save()

Synchronously save the dataset to disk.

shutdown(save=None)

Synchronously save the dataset to disk and then shut down the server.

slaveof(host=<object object>, port=None)

Make the server a slave of another instance, or promote it as master.

Calling slaveof(None) will send SLAVEOF NO ONE.

Changed in version v0.2.6: slaveof() form deprecated in favour of explicit slaveof(None).

slowlog_get(length=None)

Returns the Redis slow queries log.

slowlog_len(length=None)

Returns length of Redis slow queries log.

slowlog_reset()

Resets Redis slow queries log.

sync()

Redis-server internal command used for replication.

time()

Return current server time.

HyperLogLog commands

class aioredis.commands.HyperLogLogCommandsMixin

HyperLogLog commands mixin.

For commands details see: http://redis.io/commands#hyperloglog

pfadd(key, value, *values)

Adds the specified elements to the specified HyperLogLog.

pfcount(key, *keys)

Return the approximated cardinality of the set(s) observed by the HyperLogLog at key(s).

pfmerge(destkey, sourcekey, *sourcekeys)

Merge N different HyperLogLogs into a single one.

Transaction commands

class aioredis.commands.TransactionsCommandsMixin

Transaction commands mixin.

For commands details see: http://redis.io/commands/#transactions

Transactions HOWTO:

>>> tr = redis.multi_exec()
>>> result_future1 = tr.incr('foo')
>>> result_future2 = tr.incr('bar')
>>> try:
...     result = await tr.execute()
... except MultiExecError:
...     pass    # check what happened
>>> result1 = await result_future1
>>> result2 = await result_future2
>>> assert result == [result1, result2]
multi_exec()

Returns MULTI/EXEC pipeline wrapper.

Usage:

>>> tr = redis.multi_exec()
>>> fut1 = tr.incr('foo')   # NO `await` as it will block forever!
>>> fut2 = tr.incr('bar')
>>> result = await tr.execute()
>>> result
[1, 1]
>>> await asyncio.gather(fut1, fut2)
[1, 1]
pipeline()

Returns Pipeline object to execute bulk of commands.

It is provided for convenience. Commands can be pipelined without it.

Example:

>>> pipe = redis.pipeline()
>>> fut1 = pipe.incr('foo') # NO `await` as it will block forever!
>>> fut2 = pipe.incr('bar')
>>> result = await pipe.execute()
>>> result
[1, 1]
>>> await asyncio.gather(fut1, fut2)
[1, 1]
>>> #
>>> # The same can be done without pipeline:
>>> #
>>> fut1 = redis.incr('foo')    # the 'INCRY foo' command already sent
>>> fut2 = redis.incr('bar')
>>> await asyncio.gather(fut1, fut2)
[2, 2]
unwatch()

Forget about all watched keys.

watch(key, *keys)

Watch the given keys to determine execution of the MULTI/EXEC block.

class aioredis.commands.Pipeline(connection, commands_factory=lambda conn: conn, *, loop=None)

Commands pipeline.

Buffers commands for execution in bulk.

This class implements __getattr__ method allowing to call methods on instance created with commands_factory.

Parameters:
coroutine execute(*, return_exceptions=False)

Executes all buffered commands and returns result.

Any exception that is raised by any command is caught and raised later when processing results.

If return_exceptions is set to True then all collected errors are returned in resulting list otherwise single aioredis.PipelineError exception is raised (containing all collected errors).

Parameters:return_exceptions (bool) – Raise or return exceptions.
Raises:aioredis.PipelineError – Raised when any command caused error.
class aioredis.commands.MultiExec(connection, commands_factory=lambda conn: conn, *, loop=None)

Bases: Pipeline.

Multi/Exec pipeline wrapper.

See Pipeline for parameters description.

coroutine execute(*, return_exceptions=False)

Executes all buffered commands and returns result.

see Pipeline.execute() for details.

Parameters:

return_exceptions (bool) – Raise or return exceptions.

Raises:

Scripting commands

class aioredis.commands.ScriptingCommandsMixin

Set commands mixin.

For commands details see: http://redis.io/commands#scripting

eval(script, keys=[], args=[])

Execute a Lua script server side.

evalsha(digest, keys=[], args=[])

Execute a Lua script server side by its SHA1 digest.

script_exists(digest, *digests)

Check existence of scripts in the script cache.

script_flush()

Remove all the scripts from the script cache.

script_kill()

Kill the script currently in execution.

script_load(script)

Load the specified Lua script into the script cache.

Server commands

class aioredis.commands.ServerCommandsMixin

Server commands mixin.

For commands details see: http://redis.io/commands/#server

bgrewriteaof()

Asynchronously rewrite the append-only file.

bgsave()

Asynchronously save the dataset to disk.

client_getname(encoding=<object object>)

Get the current connection name.

client_kill()

Kill the connection of a client.

Warning

Not Implemented

client_list()

Get the list of client connections.

Returns list of ClientInfo named tuples.

client_pause(timeout)

Stop processing commands from clients for timeout milliseconds.

Raises:
client_setname(name)

Set the current connection name.

config_get(parameter='*')

Get the value of a configuration parameter(s).

If called without argument will return all parameters.

Raises:TypeError – if parameter is not string
config_resetstat()

Reset the stats returned by INFO.

config_rewrite()

Rewrite the configuration file with the in memory configuration.

config_set(parameter, value)

Set a configuration parameter to the given value.

dbsize()

Return the number of keys in the selected database.

debug_object(key)

Get debugging information about a key.

debug_segfault(key)

Make the server crash.

flushall()

Remove all keys from all databases.

flushdb()

Remove all keys from the current database.

info(section='default')

Get information and statistics about the server.

If called without argument will return default set of sections. For available sections, see http://redis.io/commands/INFO

Raises:ValueError – if section is invalid
lastsave()

Get the UNIX time stamp of the last successful save to disk.

monitor()

Listen for all requests received by the server in real time.

Warning

Will not be implemented for now.

role()

Return the role of the server instance.

Returns named tuples describing role of the instance. For fields information see http://redis.io/commands/role#output-format

save()

Synchronously save the dataset to disk.

shutdown(save=None)

Synchronously save the dataset to disk and then shut down the server.

slaveof(host=<object object>, port=None)

Make the server a slave of another instance, or promote it as master.

Calling slaveof(None) will send SLAVEOF NO ONE.

Changed in version v0.2.6: slaveof() form deprecated in favour of explicit slaveof(None).

slowlog_get(length=None)

Returns the Redis slow queries log.

slowlog_len(length=None)

Returns length of Redis slow queries log.

slowlog_reset()

Resets Redis slow queries log.

sync()

Redis-server internal command used for replication.

time()

Return current server time.

Pub/Sub commands

Also see aioredis.Channel.

class aioredis.commands.PubSubCommandsMixin

Pub/Sub commands mixin.

For commands details see: http://redis.io/commands/#pubsub

channels

Returns read-only channels dict.

See pubsub_channels

in_pubsub

Indicates that connection is in PUB/SUB mode.

Provides the number of subscribed channels.

patterns

Returns read-only patterns dict.

See pubsub_patterns

psubscribe(pattern, *patterns)

Switch connection to Pub/Sub mode and subscribe to specified patterns.

Arguments can be instances of Channel.

Returns asyncio.gather() coroutine which when done will return a list of subscribed Channel objects with is_pattern property set to True.

publish(channel, message)

Post a message to channel.

publish_json(channel, obj)

Post a JSON-encoded message to channel.

pubsub_channels(pattern=None)

Lists the currently active channels.

pubsub_numpat()

Returns the number of subscriptions to patterns.

pubsub_numsub(*channels)

Returns the number of subscribers for the specified channels.

punsubscribe(pattern, *patterns)

Unsubscribe from specific patterns.

Arguments can be instances of Channel.

subscribe(channel, *channels)

Switch connection to Pub/Sub mode and subscribe to specified channels.

Arguments can be instances of Channel.

Returns asyncio.gather() coroutine which when done will return a list of Channel objects.

unsubscribe(channel, *channels)

Unsubscribe from specific channels.

Arguments can be instances of Channel.

Cluster commands

Warning

Current release (0.3.0) of the library does not support Redis Cluster in a full manner. It provides only several API methods which may be changed in future.

aioredis.abc — Interfaces Reference

This module defines several abstract classes that must be used when implementing custom connection managers or other features.

class aioredis.abc.AbcConnection

Bases: abc.ABC

Abstract connection interface.

address

Connection address.

close()

Perform connection(s) close and resources cleanup.

closed

Flag indicating if connection is closing or already closed.

db

Current selected DB index.

encoding

Current set connection codec.

execute(command, *args, **kwargs)

Execute redis command.

execute_pubsub(command, *args, **kwargs)

Execute Redis (p)subscribe/(p)unsubscribe commands.

in_pubsub

Returns number of subscribed channels.

Can be tested as bool indicating Pub/Sub mode state.

pubsub_channels

Read-only channels dict.

pubsub_patterns

Read-only patterns dict.

coroutine wait_closed()

Coroutine waiting until all resources are closed/released/cleaned up.

class aioredis.abc.AbcPool

Bases: aioredis.abc.AbcConnection

Abstract connections pool interface.

Inherited from AbcConnection so both have common interface for executing Redis commands.

coroutine acquire()

Acquires connection from pool.

address

Connection address or None.

get_connection()

Gets free connection from pool in a sync way.

If no connection available — returns None.

release(conn)

Releases connection to pool.

Parameters:conn (AbcConnection) – Owned connection to be released.
class aioredis.abc.AbcChannel

Bases: abc.ABC

Abstract Pub/Sub Channel interface.

close()

Marks Channel as closed, no more messages will be sent to it.

Called by RedisConnection when channel is unsubscribed or connection is closed.

coroutine get()

Wait and return new message.

Will raise ChannelClosedError if channel is not active.

is_active

Flag indicating that channel has unreceived messages and not marked as closed.

is_pattern

Boolean flag indicating if channel is pattern channel.

name

Encoded channel name or pattern.

put_nowait(data)

Send data to channel.

Called by RedisConnection when new message received. For pattern subscriptions data will be a tuple of channel name and message itself.

aioredis.pubsub module

Module provides a Pub/Sub listener interface implementing multi-producers, single-consumer queue pattern.

class aioredis.pubsub.Receiver(loop=None)

Multi-producers, single-consumer Pub/Sub queue.

Can be used in cases where a single consumer task must read messages from several different channels (where pattern subscriptions may not work well or channels can be added/removed dynamically).

Example use case:

>>> from aioredis.pubsub import Receiver
>>> from aioredis.abc import AbcChannel
>>> mpsc = Receiver(loop=loop)
>>> async def reader(mpsc):
...     async for channel, msg in mpsc.iter():
...         assert isinstance(channel, AbcChannel)
...         print("Got {!r} in channel {!r}".format(msg, channel))
>>> asyncio.ensure_future(reader(mpsc))
>>> await redis.subscribe(mpsc.channel('channel:1'),
...                       mpsc.channel('channel:3'))
...                       mpsc.channel('channel:5'))
>>> await redis.psubscribe(mpsc.pattern('hello'))
>>> # publishing 'Hello world' into 'hello-channel'
>>> # will print this message:
Got b'Hello world' in channel b'hello-channel'
>>> # when all is done:
>>> await redis.unsubscribe('channel:1', 'channel:3', 'channel:5')
>>> await redis.punsubscribe('hello')
>>> mpsc.stop()
>>> # any message received after stop() will be ignored.

To do: few words regarding exclusive channel usage.

channel(name)

Create a channel.

Returns _Sender object implementing AbcChannel.

channels

Read-only channels dict.

coroutine get(*, encoding=None, decoder=None)

Wait for and return pub/sub message from one of channels.

Return value is either: * tuple of two elements: channel & message; * tuple of three elements: pattern channel, (target channel & message); * or None in case Receiver is stopped.

Raises:aioredis.ChannelClosedError – If listener is stopped and all messages have been received.
is_active

Returns True if listener has any active subscription.

pattern(pattern)

Create a pattern channel.

Returns _Sender object implementing AbcChannel.

patterns

Read-only patterns dict.

stop()

Stop receiving messages.

All new messages after this call will be ignored, so you must call unsubscribe before stopping this listener.

coroutine wait_message()

Blocks until new message appear.

class aioredis.pubsub._Sender(receiver, name, is_pattern, *, loop)

Write-Only Channel.

Does not allow direct .get() calls.

Bases: aioredis.abc.AbcChannel

Not to be used directly, returned by Receiver.channel() or Receiver.pattern() calls.

Examples of aioredis usage

Below is a list of examples from aioredis/examples (see for more).

Every example is a correct python program that can be executed.

Python 3.5 examples

Low-level connection usage example

get source code

import asyncio
import aioredis


def main():
    loop = asyncio.get_event_loop()

    async def go():
        conn = await aioredis.create_connection(
            ('localhost', 6379), encoding='utf-8')

        ok = await conn.execute('set', 'my-key', 'some value')
        assert ok == 'OK', ok

        str_value = await conn.execute('get', 'my-key')
        raw_value = await conn.execute('get', 'my-key', encoding=None)
        assert str_value == 'some value'
        assert raw_value == b'some value'

        print('str value:', str_value)
        print('raw value:', raw_value)

        # optionally close connection
        conn.close()
    loop.run_until_complete(go())


if __name__ == '__main__':
    main()

Connections pool example

get source code

import asyncio
import aioredis


def main():
    loop = asyncio.get_event_loop()

    async def go():
        pool = await aioredis.create_pool(
            ('localhost', 6379),
            minsize=5, maxsize=10)
        with await pool as redis:    # high-level redis API instance
            await redis.set('my-key', 'value')
            val = await redis.get('my-key')
        print('raw value:', val)
        pool.close()
        await pool.wait_closed()    # closing all open connections

    loop.run_until_complete(go())


if __name__ == '__main__':
    main()

Commands example

get source code

import asyncio
import aioredis


def main():
    loop = asyncio.get_event_loop()

    async def go():
        redis = await aioredis.create_redis(
            ('localhost', 6379))
        await redis.set('my-key', 'value')
        val = await redis.get('my-key')
        print(val)

        # gracefully closing underlying connection
        redis.close()
        await redis.wait_closed()
    loop.run_until_complete(go())


if __name__ == '__main__':
    main()

Transaction example

get source code

import asyncio
import aioredis


def main():
    loop = asyncio.get_event_loop()

    async def go():
        redis = await aioredis.create_redis(
            ('localhost', 6379))
        await redis.delete('foo', 'bar')
        tr = redis.multi_exec()
        fut1 = tr.incr('foo')
        fut2 = tr.incr('bar')
        res = await tr.execute()
        res2 = await asyncio.gather(fut1, fut2)
        print(res)
        assert res == res2

        redis.close()
        await redis.wait_closed()

    loop.run_until_complete(go())


if __name__ == '__main__':
    main()

Pub/Sub example

get source code

import asyncio
import aioredis


def main():
    loop = asyncio.get_event_loop()

    async def reader(ch):
        while (await ch.wait_message()):
            msg = await ch.get_json()
            print("Got Message:", msg)

    async def go():
        pub = await aioredis.create_redis(
            ('localhost', 6379))
        sub = await aioredis.create_redis(
            ('localhost', 6379))
        res = await sub.subscribe('chan:1')
        ch1 = res[0]

        tsk = asyncio.ensure_future(reader(ch1))

        res = await pub.publish_json('chan:1', ["Hello", "world"])
        assert res == 1

        await sub.unsubscribe('chan:1')
        await tsk
        sub.close()
        pub.close()

    loop.run_until_complete(go())


if __name__ == '__main__':
    main()

Scan command example

get source code

import asyncio
import aioredis


def main():
    """Scan command example."""
    loop = asyncio.get_event_loop()

    async def go():
        redis = await aioredis.create_redis(
            ('localhost', 6379))

        await redis.mset('key:1', 'value1', 'key:2', 'value2')
        cur = b'0'  # set initial cursor to 0
        while cur:
            cur, keys = await redis.scan(cur, match='key:*')
            print("Iteration results:", keys)

        redis.close()
        await redis.wait_closed()
    loop.run_until_complete(go())


if __name__ == '__main__':
    import os
    if 'redis_version:2.6' not in os.environ.get('REDIS_VERSION', ''):
        main()

Python 3.4 examples (using yield from)

Located in aioredis/examples/py34

Low-level connection usage example

get source code

import asyncio
import aioredis


def main():
    loop = asyncio.get_event_loop()

    @asyncio.coroutine
    def go():
        conn = yield from aioredis.create_connection(
            ('localhost', 6379), encoding='utf-8')

        ok = yield from conn.execute('set', 'my-key', 'some value')
        assert ok == 'OK', ok

        str_value = yield from conn.execute('get', 'my-key')
        raw_value = yield from conn.execute('get', 'my-key', encoding=None)
        assert str_value == 'some value'
        assert raw_value == b'some value'

        print('str value:', str_value)
        print('raw value:', raw_value)

        # optionally close connection
        conn.close()
    loop.run_until_complete(go())


if __name__ == '__main__':
    main()

Connections pool example

get source code

import asyncio
import aioredis


def main():
    loop = asyncio.get_event_loop()

    @asyncio.coroutine
    def go():
        pool = yield from aioredis.create_pool(
            ('localhost', 6379),
            minsize=5, maxsize=10)
        with (yield from pool) as redis:    # high-level redis API instance
            yield from redis.set('my-key', 'value')
            val = yield from redis.get('my-key')
        print('raw value:', val)
        pool.close()
        yield from pool.wait_closed()    # closing all open connections

    loop.run_until_complete(go())


if __name__ == '__main__':
    main()

Commands example

get source code

import asyncio
import aioredis


def main():
    loop = asyncio.get_event_loop()

    @asyncio.coroutine
    def go():
        redis = yield from aioredis.create_redis(
            ('localhost', 6379))
        yield from redis.set('my-key', 'value')
        val = yield from redis.get('my-key')
        print(val)

        # optinally closing underlying connection
        redis.close()
    loop.run_until_complete(go())


if __name__ == '__main__':
    main()

Transaction example

get source code

import asyncio
import aioredis


def main():
    loop = asyncio.get_event_loop()

    @asyncio.coroutine
    def go():
        redis = yield from aioredis.create_redis(
            ('localhost', 6379))
        yield from redis.delete('foo', 'bar')
        tr = redis.multi_exec()
        fut1 = tr.incr('foo')
        fut2 = tr.incr('bar')
        res = yield from tr.execute()
        res2 = yield from asyncio.gather(fut1, fut2)
        print(res)
        assert res == res2
        redis.close()
        yield from redis.wait_closed()

    loop.run_until_complete(go())


if __name__ == '__main__':
    main()

Pub/Sub example

get source code

import asyncio
import aioredis


def main():
    loop = asyncio.get_event_loop()

    @asyncio.coroutine
    def reader(ch):
        while (yield from ch.wait_message()):
            msg = yield from ch.get_json()
            print("Got Message:", msg)

    @asyncio.coroutine
    def go():
        pub = yield from aioredis.create_redis(
            ('localhost', 6379))
        sub = yield from aioredis.create_redis(
            ('localhost', 6379))
        res = yield from sub.subscribe('chan:1')
        ch1 = res[0]

        tsk = asyncio.async(reader(ch1))

        res = yield from pub.publish_json('chan:1', ["Hello", "world"])
        assert res == 1

        yield from sub.unsubscribe('chan:1')
        yield from tsk
        sub.close()
        pub.close()

    loop.run_until_complete(go())


if __name__ == '__main__':
    main()

Scan command example

get source code

import asyncio
import aioredis


def main():
    """Scan command example."""
    loop = asyncio.get_event_loop()

    @asyncio.coroutine
    def go():
        redis = yield from aioredis.create_redis(
            ('localhost', 6379))

        yield from redis.mset('key:1', 'value1', 'key:2', 'value2')
        cur = b'0'  # set initial cursor to 0
        while cur:
            cur, keys = yield from redis.scan(cur, match='key:*')
            print("Iteration results:", keys)

        redis.close()
        yield from redis.wait_closed()
    loop.run_until_complete(go())


if __name__ == '__main__':
    import os
    if 'redis_version:2.6' not in os.environ.get('REDIS_VERSION', ''):
        main()

Contributing

To start contributing you must read all the following.

First you must fork/clone repo from github:

$ git clone git@github.com:aio-libs/aioredis.git

Next, you should install all python dependencies, it is as easy as running single command:

$ make devel

this command will install:

  • sphinx for building documentation;
  • pytest for running tests;
  • flake8 for code linting;
  • and few other packages.

Code style

Code must be pep8 compliant.

You can check it with following command:

$ make flake

Running tests

You can run tests in any of the following ways:

# will run tests in a verbose mode
$ make test
# or
$ py.test

# will run tests with coverage report
$ make cov
# or
$ py.test --cov

SSL tests

Running SSL tests requires following additional programs to be installed:

  • openssl – to generate test key and certificate;
  • socat – to make SSL proxy;

To install these on Ubuntu and generate test key & certificate run:

$ sudo apt-get install socat openssl
$ make certificate

Different Redis server versions

To run tests against different redises use --redis-server command line option:

$ py.test --redis-server=/path/to/custom/redis-server

UVLoop

To run tests with uvloop:

$ pip install uvloop
$ py.test --uvloop

Note

Until Python 3.5.2 EventLoop has no create_future method so aioredis won’t benefit from uvloop’s futures.

Writing tests

aioredis uses pytest tool.

Tests are located under /tests directory.

Pure Python 3.5 tests (ie the ones using async/await syntax) must be prefixed with py35_, for instance see:

tests/py35_generic_commands_tests.py
tests/py35_pool_test.py

Fixtures

There is a number of fixtures that can be used to write tests:

loop

Current event loop used for test. This is a function-scope fixture. Using this fixture will always create new event loop and set global one to None.

def test_with_loop(loop):
    @asyncio.coroutine
    def do_something():
        pass
    loop.run_until_complete(do_something())
unused_port()

Finds and returns free TCP port.

def test_bind(unused_port):
    port = unused_port()
    assert 1024 < port <= 65535
coroutine create_connection(*args, **kw)

Wrapper around aioredis.create_connection(). Only difference is that it registers connection to be closed after test case, so you should not be worried about unclosed connections.

coroutine create_redis(*args, **kw)

Wrapper around aioredis.create_redis().

coroutine create_pool(*args, **kw)

Wrapper around aioredis.create_pool().

redis

Redis client instance.

pool

RedisPool instance.

server

Redis server instance info. Namedtuple with following properties:

name
server instance name.
port
Bind port.
unixsocket
Bind unixsocket path.
version
Redis server version tuple.
serverB

Second predefined Redis server instance info.

start_server(name)

Start Redis server instance. Redis instances are cached by name.

Returns:server info tuple, see server.
Return type:tuple
ssl_proxy(unsecure_port)

Start SSL proxy.

Parameters:unsecure_port (int) – Redis server instance port
Returns:secure_port and ssl_context pair
Return type:tuple

Helpers

aioredis also updates pytest‘s namespace with several helpers.

pytest.redis_version(*version, reason)

Marks test with minimum redis version to run.

Example:

@pytest.redis_version(3, 2, 0, reason="HSTRLEN new in redis 3.2.0")
def test_hstrlen(redis):
    pass
pytest.logs(logger, level=None)

Adopted version of unittest.TestCase.assertEqual(), see it for details.

Example:

def test_logs(create_connection, server):
    with pytest.logs('aioredis', 'DEBUG') as cm:
        conn yield from create_connection(server.tcp_address)
    assert cm.output[0].startswith(
      'DEBUG:aioredis:Creating tcp connection')
pytest.assert_almost_equal(first, second, places=None, msg=None, delta=None)

Adopted version of unittest.TestCase.assertAlmostEqual().

pytest.raises_regex(exc_type, message)

Adopted version of unittest.TestCase.assertRaisesRegex().

Releases

Recent

0.3.0 (2017-01-11)

NEW:

  • Pub/Sub connection commands accept Channel instances (see #168);
  • Implement new Pub/Sub MPSC (multi-producers, single-consumer) Queue – aioredis.pubsub.Receiver (see #176);
  • Add aioredis.abc module providing abstract base classes defining interface for basic lib components; (see #176);
  • Implement Geo commands support (see #177 and #179);

FIX:

  • Minor tests fixes;

MISC:

  • Update examples and docs to use async/await syntax also keeping yield from examples for history (see #173);
  • Reflow Travis CI configuration; add Python 3.6 section (see #170);
  • Add AppVeyor integration to run tests on Windows (see #180);
  • Update multiple development requirements;

0.2.9 (2016-10-24)

NEW:

  • Allow multiple keys in EXISTS command (see #156 and #157);

FIX:

  • Close RedisPool when connection to Redis failed (see #136);
  • Add simple INFO command argument validation (see #140);
  • Remove invalid uses of next()

MISC:

  • Update devel.rst docs; update Pub/Sub Channel docs (cross-refs);
  • Update MANIFEST.in to include docs, examples and tests in source bundle;

0.2.8 (2016-07-22)

NEW:

  • Add hmset_dict command (see #130);
  • Add RedisConnection.address property;
  • RedisPool minsize/maxsize must not be None;
  • Implement close()/wait_closed()/closed interface for pool (see #128);

FIX:

  • Add test for hstrlen;
  • Test fixes

MISC:

  • Enable Redis 3.2.0 on Travis;
  • Add spell checking when building docs (see #132);
  • Documentation updated;

0.2.7 (2016-05-27)

  • create_pool() minsize default value changed to 1;
  • Fixed cancellation of wait_closed (see #118);
  • Fixed time() convertion to float (see #126);
  • Fixed hmset() method to return bool instead of b'OK' (see #126);
  • Fixed multi/exec + watch issue (changed watch variable was causing tr.execute() to fail) (see #121);
  • Replace asyncio.Future uses with utility method (get ready to Python 3.5.2 loop.create_future());
  • Tests switched from unittest to pytest (see #126);
  • Documentation updates;

0.2.6 (2016-03-30)

  • Fixed Multi/Exec transactions cancellation issue (see #110 and #114);
  • Fixed Pub/Sub subscribe concurrency issue (see #113 and #115);
  • Add SSL/TLS support (see #116);
  • aioredis.ConnectionClosedError raised in execute_pubsub as well (see #108);
  • Redis.slaveof() method signature changed: now to disable replication one should call redis.slaveof(None) instead of redis.slaveof();
  • More tests added;

0.2.5 (2016-03-02)

  • Close all Pub/Sub channels on connection close (see #88);
  • Add iter() method to aioredis.Channel allowing to use it with async for (see #89);
  • Inline code samples in docs made runnable and downloadable (see #92);
  • Python 3.5 examples converted to use async/await syntax (see #93);
  • Fix Multi/Exec to honor encoding parameter (see #94 and #97);
  • Add debug message in create_connection (see #90);
  • Replace asyncio.async calls with wrapper that respects asyncio version (see #101);
  • Use NODELAY option for TCP sockets (see #105);
  • New aioredis.ConnectionClosedError exception added. Raised if connection to Redis server is lost (see #108 and #109);
  • Fix RedisPool to close and drop connection in subscribe mode on release;
  • Fix aioredis.util.decode to recursively decode list responses;
  • More examples added and docs updated;
  • Add google groups link to README;
  • Bump year in LICENSE and docs;

0.2.4 (2015-10-13)

  • Python 3.5 async support:
    • New scan commands API (iscan, izscan, ihscan);
    • Pool made awaitable (allowing with await pool: ... and async with pool.get() as conn: constructs);
  • Fixed dropping closed connections from free pool (see #83);
  • Docs updated;

0.2.3 (2015-08-14)

  • Redis cluster support work in progress;
  • Fixed pool issue causing pool growth over max size & acquire call hangs (see #71);
  • info server command result parsing implemented;
  • Fixed behavior of util functions (see #70);
  • hstrlen command added;
  • Few fixes in examples;
  • Few fixes in documentation;

0.2.2 (2015-07-07)

  • Decoding data with encoding parameter now takes into account list (array) replies (see #68);

  • encoding parameter added to following commands:

    • generic commands: keys, randomkey;
    • hash commands: hgetall, hkeys, hmget, hvals;
    • list commands: blpop, brpop, brpoplpush, lindex, lpop, lrange, rpop, rpoplpush;
    • set commands: smembers, spop, srandmember;
    • string commands: getrange, getset, mget;
  • Backward incompatibility:

    ltrim command now returns bool value instead of ‘OK’;

  • Tests updated;

0.2.1 (2015-07-06)

  • Logging added (aioredis.log module);
  • Fixed issue with wait_message in pub/sub (see #66);

0.2.0 (2015-06-04)

  • Pub/Sub support added;
  • Fix in zrevrangebyscore command (see #62);
  • Fixes/tests/docs;

Historical

0.1.5 (2014-12-09)

  • AutoConnector added;
  • wait_closed method added for clean connections shutdown;
  • zscore command fixed;
  • Test fixes;

0.1.4 (2014-09-22)

  • Dropped following Redis methods – Redis.multi(), Redis.exec(), Redis.discard();

  • Redis.multi_exec hack’ish property removed;

  • Redis.multi_exec() method added;

  • High-level commands implemented:

    • generic commands (tests);
    • transactions commands (api stabilization).
  • Backward incompatibilities:

    • Following sorted set commands’ API changed:

      zcount, zrangebyscore, zremrangebyscore, zrevrangebyscore;

    • set string command’ API changed;

0.1.3 (2014-08-08)

  • RedisConnection.execute refactored to support commands pipelining (see #33);
  • Several fixes;
  • WIP on transactions and commands interface;
  • High-level commands implemented and tested:
    • hash commands;
    • hyperloglog commands;
    • set commands;
    • scripting commands;
    • string commands;
    • list commands;

0.1.2 (2014-07-31)

  • create_connection, create_pool, create_redis functions updated: db and password arguments made keyword-only (see #26);
  • Fixed transaction handling (see #32);
  • Response decoding (see #16);

0.1.1 (2014-07-07)

  • Transactions support (in connection, high-level commands have some issues);
  • Docs & tests updated.

0.1.0 (2014-06-24)

  • Initial release;
  • RedisConnection implemented;
  • RedisPool implemented;
  • Docs for RedisConnection & RedisPool;
  • WIP on high-level API.

Glossary

asyncio

Reference implementation of PEP 3156

See https://pypi.python.org/pypi/asyncio

error replies
Redis server replies that start with - (minus) char. Usually starts with -ERR.
hiredis

Python extension that wraps protocol parsing code in hiredis.

See https://pypi.python.org/pypi/hiredis

pytest
A mature full-featured Python testing tool. See http://pytest.org/latest/
uvloop
Is an ultra fast implementation of asyncio event loop on top of libuv. See https://github.com/MagicStack/uvloop

Indices and tables