python使用redis实现消息队列(异步)的实现完整例程

pip install aioredis

export APP_ENV=development

export REDIS_URL="192.168.70.130/"
export REDIS_USER=
export REDIS_PASSWord=
export REDIS_HOST="192.168.70.130"
export REDIS_PORT=6379

import os
from dotenv import load_dotenv
import aioredis
import asyncio

load_dotenv()

class Redis():
  def __init__(self):
    """initialize connection """
    self.REDIS_URL = os.environ['REDIS_URL']
    self.REDIS_PASSWORD = os.environ['REDIS_PASSWORD']
    self.REDIS_USER = os.environ['REDIS_USER']
    self.connection_url = f"redis://{self.REDIS_USER}:{self.REDIS_PASSWORD}@{self.REDIS_URL}"
    self.REDIS_HOST = os.environ['REDIS_HOST']
    self.REDIS_PORT = os.environ['REDIS_PORT']
   
  async def create_connection(self):
    self.connection = aioredis.from_url(
      self.connection_url, db=0)

    return self.connection


class Producer:
  def __init__(self, redis_client):
    self.redis_client = redis_client

  async def add_to_stream(self, data: dict, stream_channel):
    """将一条数据添加到队列

    Args:
      data (dict): _description_
      stream_channel (_type_): _description_

    Returns:
      _type_: _description_
    """
    try:
      msg_id = await self.redis_client.xadd(name=stream_channel, id="*", fields=data)
      print(f"Message id {msg_id} added to {stream_channel} stream")
      return msg_id

    except Exception as e:
      raise Exception(f"Error sending msg to stream => {e}")

class StreamConsumer:
  def __init__(self, redis_client):
    self.redis_client = redis_client

  async def consume_stream(self, count: int, block: int, stream_channel):
    """读取队列中的消息，但是并不删除

    Args:
      count (int): _description_
      block (int): _description_
      stream_channel (_type_): _description_

    Returns:
      _type_: _description_
    """
    response = await self.redis_client.xread(
      streams={stream_channel: '0-0'}, count=count, block=block)

    return response

  async def delete_message(self, stream_channel, message_id):
    """成功消费数据后，调用此函数删除队列数据

    Args:
      stream_channel (_type_): _description_
      message_id (_type_): _description_
    """
    await self.redis_client.xdel(stream_channel, message_id)


async def main():
  redis_conn = await Redis().create_connection()
  produce = Producer(redis_conn)
  consumer = StreamConsumer(redis_conn)
  # 添加一个消息到队列中
  data = {'xiaoming4':123}
  await produce.add_to_stream(data=data,stream_channel='message_channel')
 
  # 从队列中拿出最新的1条数据
  data = await consumer.consume_stream(1,block=0,stream_channel='message_channel')
  print(data)
 
  # 轮询等待队列中的新消息
  response = await consumer.consume_stream(stream_channel="message_channel", count=1, block=0)
  if response:
    for stream, messagees in response:
      print('stream:',stream)
      for message in messagees:
        print('message: ',message)
        message_id = message[0]
        print('message_id: ',message_id)
        message_content = message[1]
        print('message_content: ',message_content)
        print('注意里面的键、值都变成了byte类型，需要进行解码:')
        message_content:dict
        print('message_content_decode: ',{k.decode('utf-8'):v.decode('utf-8') for k,v in message_content.items()})

  # 消费成功后删除队列中的消息
  await consumer.delete_message(
    stream_channel='message_channel',message_id=message_id
  )  

if __name__ == '__main__':
  asyncio.run(main())