要實(shí)現(xiàn)RabbitMQ的同步返回結(jié)果,可以使用RabbitMQ的RPC機(jī)制。RPC(Remote Procedure Call)是一種進(jìn)程間通信的方式,它允許一個(gè)程序調(diào)用另一個(gè)程序中的函數(shù)或方法,就像調(diào)用本地函數(shù)一樣。
下面是實(shí)現(xiàn)RabbitMQ同步返回結(jié)果的大致步驟:
具體實(shí)現(xiàn)步驟如下:
以下是一個(gè)簡單的示例代碼:
RPC客戶端:
import pika
import uuid
class RpcClient:
def __init__(self):
self.connection = pika.BlockingConnection(pika.ConnectionParameters('localhost'))
self.channel = self.connection.channel()
result = self.channel.queue_declare(queue='', exclusive=True)
self.callback_queue = result.method.queue
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.correlation_id == props.correlation_id:
self.response = body
def call(self, message):
self.response = None
self.correlation_id = str(uuid.uuid4())
self.channel.basic_publish(
exchange='',
routing_key='rpc_queue',
properties=pika.BasicProperties(
reply_to=self.callback_queue,
correlation_id=self.correlation_id,
),
body=message)
while self.response is None:
self.connection.process_data_events()
return self.response
rpc_client = RpcClient()
response = rpc_client.call('Hello, World!')
print(response)
RPC服務(wù)器:
import pika
class RpcServer:
def __init__(self):
self.connection = pika.BlockingConnection(pika.ConnectionParameters('localhost'))
self.channel = self.connection.channel()
self.channel.queue_declare(queue='rpc_queue')
self.channel.basic_qos(prefetch_count=1)
self.channel.basic_consume(queue='rpc_queue', on_message_callback=self.on_request)
def on_request(self, ch, method, props, body):
message = body.decode()
response = self.process_request(message)
ch.basic_publish(
exchange='',
routing_key=props.reply_to,
properties=pika.BasicProperties(correlation_id=props.correlation_id),
body=str(response))
ch.basic_ack(delivery_tag=method.delivery_tag)
def process_request(self, message):
# 處理請(qǐng)求的邏輯
response = 'Hello, ' + message
return response
rpc_server = RpcServer()
rpc_server.channel.start_consuming()
在上面的示例代碼中,客戶端發(fā)送請(qǐng)求消息時(shí),將回調(diào)隊(duì)列的名稱作為消息屬性的值發(fā)送給服務(wù)器。服務(wù)器在處理請(qǐng)求時(shí),將結(jié)果發(fā)送到回調(diào)隊(duì)列??蛻舳嗽诎l(fā)送請(qǐng)求后,開始監(jiān)聽回調(diào)隊(duì)列,等待接收結(jié)果??蛻舳私邮盏浇Y(jié)果后,將結(jié)果返回給調(diào)用者。
注意:上述示例代碼是使用Python的pika庫實(shí)現(xiàn)的,如果使用其他編程語言,可以參考相應(yīng)語言的RabbitMQ RPC實(shí)現(xiàn)方式。