RabbitMQ 入门教程
概述
RabbitMQ 是一个开源的消息代理和队列服务器，实现了高级消息队列协议 (AMQP)。它能够接收、存储和转发消息数据。本教程将引导你完成搭建RabbitMQ环境、编写生产者与消费者程序的过程。
安装与配置
1. 安装RabbitMQ
Linux
```bash
sudo apt-get update
sudo apt-get install rabbitmq-server
```
Windows
- 下载安装包: https://www.rabbitmq.com/download.html
- 运行安装向导
2. 启动服务
```bash
sudo service rabbitmq-server start
```
3. 配置环境
创建用户
```bash
rabbitmqctl add_user myuser mypassword
```
设置权限
```bash
rabbitmqctl set_user_tags myuser administrator
rabbitmqctl set_permissions -p / myuser ".*" ".*" ".*"
```
开发环境准备
Python开发环境
安装Pika库
```bash
pip install pika
```
示例代码
生产者
文件: `producer.py`
```python
import pika
connection = pika.BlockingConnection(pika.ConnectionParameters('localhost'))
channel = connection.channel()
声明队列
channel.queue_declare(queue='hello')
发送消息
channel.basic_publish(exchange='',
routing_key='hello',
body='Hello World!')
print(" [x] Sent 'Hello World!'")
connection.close()
```
消费者
文件: `consumer.py`
```python
import pika
def callback(ch, method, properties, body):
print(" [x] Received %r" % body)
connection = pika.BlockingConnection(pika.ConnectionParameters('localhost'))
channel = connection.channel()
声明队列
channel.queue_declare(queue='hello')
消费消息
channel.basic_consume(queue='hello',
on_message_callback=callback,
auto_ack=True)
print(' [*] Waiting for messages. To exit press CTRL+C')
channel.start_consuming()
```
运行示例
启动生产者
```bash
python producer.py
```
启动消费者
```bash
python consumer.py
```
高级特性
1. 工作队列
生产者 (`work_queue_producer.py`)
```python
import pika
import time
connection = pika.BlockingConnection(pika.ConnectionParameters('localhost'))
channel = connection.channel()
channel.queue_declare(queue='task_queue', durable=True)
message = "Hello World!"
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()
```
消费者 (`work_queue_consumer.py`)
```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()
```
2. 发布/订阅模式
生产者 (`pubsub_producer.py`)
```python
import pika
connection = pika.BlockingConnection(pika.ConnectionParameters('localhost'))
channel = connection.channel()
channel.exchange_declare(exchange='logs', exchange_type='fanout')
message = "Hello World!"
channel.basic_publish(exchange='logs',
routing_key='',
body=message)
print(" [x] Sent %r" % message)
connection.close()
```
消费者 (`pubsub_consumer.py`)
```python
import pika
import sys
def callback(ch, method, properties, body):
print(" [x] Received %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()
```
总结
通过以上步骤，你已经了解了如何使用Python和RabbitMQ进行基本的消息传递。RabbitMQ提供了许多高级特性和功能，可以支持复杂的系统架构需求。
```