RabbitMQ 入门教程

1. 引言

RabbitMQ 是一个开源的消息代理和队列服务器，实现高级消息队列协议 (AMQP)。它能帮助开发者实现应用程序间的解耦、异步处理、流量削峰等需求。

2. 安装与配置

2.1 安装RabbitMQ

2.1.1 Ubuntu

```bash

sudo apt-get update

sudo apt-get install rabbitmq-server

```

2.1.2 Windows

1. 下载安装包: [RabbitMQ Download](https://www.rabbitmq.com/download.html)

2. 运行安装向导。

2.2 启动服务

```bash

sudo service rabbitmq-server start

```

2.3 配置管理插件

```bash

sudo rabbitmq-plugins enable rabbitmq_management

```

2.4 访问管理界面

- 浏览器访问: `http://localhost:15672/`

- 默认用户名/密码: `guest/guest`

3. Python 开发环境准备

3.1 安装pika库

```bash

pip install pika

```

4. Hello World 示例

4.1 发送端 - send.py

```python

import pika

connection = pika.BlockingConnection(pika.ConnectionParameters('localhost'))

channel = connection.channel()

channel.queue_declare(queue='hello')

channel.basic_publish(exchange='',

routing_key='hello',

body='Hello World!')

print(" [x] Sent 'Hello World!'")

connection.close()

```

4.2 接收端 - receive.py

```python

import pika

def callback(ch, method, properties, body):

print(" [x] Received %r" % body)

connection = pika.BlockingConnection(pika.ConnectionParameters('localhost'))

channel = connection.channel()

channel.queue_declare(queue='hello')

channel.basic_consume(queue='hello',

on_message_callback=callback,

auto_ack=True)

print(' [*] Waiting for messages. To exit press CTRL+C')

channel.start_consuming()

```

5. 工作队列

5.1 创建工作队列

```python

import pika

import time

connection = pika.BlockingConnection(pika.ConnectionParameters('localhost'))

channel = connection.channel()

channel.queue_declare(queue='task_queue', durable=True)

message = "A message"

channel.basic_publish(exchange='',

routing_key='task_queue',

body=message,

properties=pika.BasicProperties(

delivery_mode=2, # make message persistent

))

print(" [x] Sent %r" % message)

connection.close()

```

5.2 消费者

```python

import pika

import time

def callback(ch, method, properties, body):

print(" [x] Received %r" % body)

time.sleep(body.count(b'.'))

print(" [x] Done")

ch.basic_ack(delivery_tag=method.delivery_tag)

connection = pika.BlockingConnection(pika.ConnectionParameters('localhost'))

channel = connection.channel()

channel.queue_declare(queue='task_queue', durable=True)

print(' [*] Waiting for messages. To exit press CTRL+C')

channel.basic_qos(prefetch_count=1)

channel.basic_consume(queue='task_queue',

on_message_callback=callback)

channel.start_consuming()

```

6. 发布/订阅模式

6.1 发布者

```python

import pika

connection = pika.BlockingConnection(pika.ConnectionParameters('localhost'))

channel = connection.channel()

channel.exchange_declare(exchange='logs', exchange_type='fanout')

message = "Log message"

channel.basic_publish(exchange='logs',

routing_key='',

body=message)

print(" [x] Sent %r" % message)

connection.close()

```

6.2 订阅者

```python

import pika

import sys

def callback(ch, method, properties, body):

print(" [x] %r" % body)

connection = pika.BlockingConnection(pika.ConnectionParameters('localhost'))

channel = connection.channel()

channel.exchange_declare(exchange='logs', exchange_type='fanout')

result = channel.queue_declare(queue='', exclusive=True)

queue_name = result.method.queue

channel.queue_bind(exchange='logs', queue=queue_name)

print(' [*] Waiting for logs. To exit press CTRL+C')

channel.basic_consume(queue=queue_name,

on_message_callback=callback,

auto_ack=True)

channel.start_consuming()

```

7. 路由模式

7.1 发布者

```python

import pika

connection = pika.BlockingConnection(pika.ConnectionParameters('localhost'))

channel = connection.channel()

channel.exchange_declare(exchange='direct_logs', exchange_type='direct')

severity = "info"

message = "Info message"

channel.basic_publish(exchange='direct_logs',

routing_key=severity,

body=message)

print(" [x] Sent %r:%r" % (severity, message))

connection.close()

```

7.2 订阅者

```python

import pika

def callback(ch, method, properties, body):

print(" [x] %r:%r" % (method.routing_key, body))

connection = pika.BlockingConnection(pika.ConnectionParameters('localhost'))

channel = connection.channel()

channel.exchange_declare(exchange='direct_logs', exchange_type='direct')

severities = ["info", "warning"]

result = channel.queue_declare(queue='', exclusive=True)

queue_name = result.method.queue

for severity in severities:

channel.queue_bind(exchange='direct_logs',

queue=queue_name,

routing_key=severity)

print(' [*] Waiting for logs. To exit press CTRL+C')

channel.basic_consume(queue=queue_name,

on_message_callback=callback,

auto_ack=True)

channel.start_consuming()

```

8. 主题模式

8.1 发布者

```python

import pika

connection = pika.BlockingConnection(pika.ConnectionParameters('localhost'))

channel = connection.channel()

channel.exchange_declare(exchange='topic_logs', exchange_type='topic')

routing_key = "kern.critical"

message = "Kernel critical message"

channel.basic_publish(exchange='topic_logs',

routing_key=routing_key,

body=message)

print(" [x] Sent %r:%r" % (routing_key, message))

connection.close()

```

8.2 订阅者

```python

import pika

def callback(ch, method, properties, body):

print(" [x] %r:%r" % (method.routing_key, body))

connection = pika.BlockingConnection(pika.ConnectionParameters('localhost'))

channel = connection.channel()

channel.exchange_declare(exchange='topic_logs', exchange_type='topic')

result = channel.queue_declare(queue='', exclusive=True)

queue_name = result.method.queue

binding_keys = ["kern.*", "*.critical"]

for binding_key in binding_keys:

channel.queue_bind(exchange='topic_logs',

queue=queue_name,

routing_key=binding_key)

print(' [*] Waiting for logs. To exit press CTRL+C')

channel.basic_consume(queue=queue_name,

on_message_callback=callback,

auto_ack=True)

channel.start_consuming()

```