redis-websocket-api 0.0.4

Redis-over-WebSocket API on top of websockets and aioredis

An extensible Redis-over-WebSocket API on top of websockets and aioredis.

Installation

For basic functionality:

pip install redis_websocket_api

With geo extension (filtering messages by extent, projection transformation):

pip install redis_websocket_api[geo]

Server-Side Usage

Start the WebsocketServer like this:

from aioredis import create_redis_pool
from redis_websocket_api import WebsocketServer

REDIS_ADDRESS = ('localhost', 6379)


WebsocketServer(
    redis=loop.run_until_complete(create_redis_pool(REDIS_ADDRESS)),
    subscriber=loop.run_until_complete(create_redis_pool(REDIS_ADDRESS)),
    read_timeout=30,
    keep_alive_timeout=120,
).listen(
    host='localhost',
    port=8000,
    channel_names=('public_channel_1', 'public_channel_2'),
)

Have a look at examples/demo.py for an example with the GeoCommandsMixin added.

Client-Side Usage

WebsocketHandler

The default functionality provides the following interface to the web client (expecting the requests over a websocket connection):

• GET key translates to hvals key
• GET key hkey translates to hget key hkey
• SUB key subscribes the websocket to a redis channel (using a single redis connection pool for all clients)
• DEL key unsubscribes the client from the channel
• PING causes a PONG response (to avoid timeouts)

Subclass of WebsocketHandler with GeoCommandsMixin added

By adding the GeoCommandsMixin the web client can use

• BBOX left bottom right top to only receive GeoJSON features within this box plus all messages which are not valid GeoJSON
• PROJECTION epsg:number causes all future GeoJSON features to be transformed to the given projection

See examples/demo.py for how to use an extended WebsocketHandler subclass.

Geo commands are currently limited to LineString, Polygon, and Point geometries.

Build your own protocol

Using the commands listed above for communicating from client to server is completly optional and determinded by the Mixin classes added to the WebsocketHandlerBase.