RabbitMQ应用示例

更多详情参考官方文档：https://www.rabbitmq.com/tutorials/tutorial-six-python.html

参考博客：https://blog.csdn.net/weixin_41896508/article/details/80997828

微服务通信RPC

01-HelloWorld(简单的消息队列)

　　send.py　　

import pika
#与RabbitMQ服务器建立连接
credential = pika.PlainCredentials('yang','abc123456')#erase_on_connect是否清楚凭证
connection = pika.BlockingConnection(pika.ConnectionParameters('localhost',credentials=credential))
#创建频道
channel = connection.channel()#channel_number参数指定频道编号，建议默认pika自行管理
#创建频道传递消息的队列
channel.queue_declare(queue='hello')

#向频道队列中发送消息
channel.basic_publish(exchange='',
                      routing_key='hello',
                      body='hello world!')

print('[x]消息发送成功！')
connection.close()#断开连接

send.py

　　receive.py

import pika
credentials = pika.PlainCredentials('yang','abc123456')
connection = pika.BlockingConnection(pika.ConnectionParameters(host='127.0.0.1',port=5672,credentials=credentials))
channel = connection.channel()
channel.queue_declare(queue='hello')

def callback(ch, method, properties, body):
    print(f'{body.decode()}')

channel.basic_consume(queue='hello',
                      auto_ack=True,#开启自动确认关闭手动确认
                      on_message_callback=callback)

print(' [*] Waiting for messages. ')
channel.start_consuming()

recieve.py

02-WorkQueues（任务队列）

　　new_task.py　　

'''
任务生产者将任务发送到指定队列中，多个工作者进行均分协同处理（启多个工作者）
'''
import pika
credentials = pika.PlainCredentials('yang','abc123456')
connection = pika.BlockingConnection(pika.ConnectionParameters('127.0.0.1',5672,credentials=credentials))
channel = connection.channel()

channel.queue_declare(queue='work_queue',durable=True)#durable=True指定消息持久化，出现异常不会丢失。注意basic_publish需要设置参数

for i in range(1000):
    message = f'new_task{i}...'
    channel.basic_publish(
        exchange='',
        routing_key='work_queue',
        body=message,
        properties = pika.BasicProperties(delivery_mode=2, )# 支持数据持久化:2代表消息是持久
    )
    print(f'Send>>>{message}')

connection.close()

new_task.py

　　worker.py

import time
import random
import pika
credentials = pika.PlainCredentials('yang','abc123456')
connection = pika.BlockingConnection(pika.ConnectionParameters('127.0.0.1',5672,credentials=credentials))
channel = connection.channel()

channel.queue_declare(queue='work_queue',durable=True)#durable=True指定消息持久化，出现异常不会丢失

def callback(ch, method, properties, body):
    print(f'Rceive>>{body}')
    time.sleep(random.random())
    print(f'Done--{body.decode()}')
    # 手动确认机制（在消费者挂掉没有给确认时，消息不会丢失）
    ch.basic_ack(delivery_tag=method.delivery_tag)

channel.basic_qos(prefetch_count=1)#此设置确保在没有进行确认之前当前接受得任务只有1个（不设置默认是平均分配）
channel.basic_consume(
    queue='work_queue',
    on_message_callback=callback
)

channel.start_consuming()

worker.py

03-PublishSubcribe(订阅发布)

　　publish.py　

'''
发布者发布一条任务，通过交换机发送到与此交换机简历连接的所有队列中进行共享（启多个订阅者）
'''
import pika
credentials = pika.PlainCredentials('yang','abc123456')
connection = pika.BlockingConnection(pika.ConnectionParameters(host='127.0.0.1', port=5672, credentials=credentials))

channel = connection.channel()

#创建频道的交换器（交换器负责将任务发送到连接词交换器的所有的队列中）
channel.exchange_declare(exchange='logs',
                         exchange_type='fanout',#创建一个fanout(广播)类型的交换机exchange，名字为logs
                         durable=True)#durabl持久化

for i in range(1000):
    message = f'new_task{i}...'
    channel.basic_publish(
        exchange='logs',#指定交换机
        routing_key='',#无需指定路由键队列，由交换机进行发送
        body=message,
        properties = pika.BasicProperties(delivery_mode=2, )# delivery_mode支持数据持久化:2代表消息是持久
    )
    print(f'Send>>>{message}')

connection.close()

publish.py

　　subcribe.py

import pika
credentials = pika.PlainCredentials('yang','abc123456')
connection = pika.BlockingConnection(pika.ConnectionParameters(host='127.0.0.1', port=5672, credentials=credentials))

channel = connection.channel()

#与交换器建立连接
channel.exchange_declare(exchange='logs',exchange_type='fanout',durable=True)#durable持久化

#确定消息队列（不指定队列名，每个订阅者rabbirmq服务器连接都会创建一个随机队列）
result= channel.queue_declare(queue='',exclusive=True,durable=True)#exclusive=True当断开连接时，队列销毁(持久化没有用，设置了断开销毁)
queue_name= result.method.queue
#与交换机新建的的随机队列进行绑定
channel.queue_bind(exchange='logs',queue=queue_name)

def callback(ch, method, properties, body):
    print(f'Rceive>>{body}')
    print(f'Done--{body.decode()}')
    # 手动确认机制（在消费者挂掉没有给确认时，消息不会丢失）
    ch.basic_ack(delivery_tag=method.delivery_tag)

channel.basic_consume(
    queue=queue_name,
    on_message_callback=callback
)

channel.start_consuming()

subcribe.py

06-RPC(远程过程调用)

　　rpc_client.py

import pika
import uuid

class RpcClient(object):
    def __init__(self):
        credentials = pika.PlainCredentials('yang', 'abc123456')
        self.connection = pika.BlockingConnection(pika.ConnectionParameters('127.0.0.1', 5672, credentials=credentials))

        self.channel = self.connection.channel()

        # 随机创建一个唯一队列
        result = self.channel.queue_declare(queue='', exclusive=True)
        self.callback_queue = result.method.queue

        # 接收回调队列中的消息
        self.channel.basic_consume(
            queue=self.callback_queue,
            on_message_callback=self.on_response,
            auto_ack=True)

    def on_response(self, ch, method, props, body):
        if self.corr_id == props.correlation_id:
            self.response = body

    def call(self, m, n):
        self.response = None
        self.corr_id = str(uuid.uuid4())
        # 想通信队列放入消息
        self.channel.basic_publish(
            exchange='',
            routing_key='rpc_queue',
            properties=pika.BasicProperties(
                delivery_mode=2,#持久化参数
                # content_type='application/json',#指定body数据类型，不指定则为字符串(有待测试)
                reply_to=self.callback_queue,  # 指定回调队列
                correlation_id=self.corr_id,  # 指定本次请求标识id
            ),
            body=str(m) + ',' + str(n)
        )

        while self.response is None:
            self.connection.process_data_events()
        return int(self.response)

clinet_rpc = RpcClient()

print(" [x] Requesting add(30,30)")
response = clinet_rpc.call(30,20)
print(" [.] Got %r" % response)

rpc_client.py

　　rpc_server.py

import pika

credentials = pika.PlainCredentials('yang', 'abc123456')
connection = pika.BlockingConnection(pika.ConnectionParameters('127.0.0.1', 5672, credentials=credentials))
channel = connection.channel()

channel.queue_declare(queue='rpc_queue', durable=True)  # durable=True消息持久化

def add(m, n):
    return m + n

def on_request(ch, method, props, body):
    m, n = body.decode().split(',')
    response = add(int(m), int(n))

    #将响应信息放入指定的回调队列中
    channel.basic_publish(
        exchange='',
        routing_key=props.reply_to,#请求指定的响应队列
        properties=pika.BasicProperties(correlation_id=props.correlation_id,),#请求设定的标识（无需设置持久化，每次响应之后回调队列销毁）
        body=str(response)
    )
    ch.basic_ack(delivery_tag=method.delivery_tag)  # 手动回复确认

channel.basic_qos(prefetch_count=1)  # 在没有确认前只分配一个任务
channel.basic_consume(
    queue='rpc_queue',
    on_message_callback=on_request,
)

print('Awaiting RPC requests...')
channel.start_consuming()

rpc_server.py