那些年被我坑过的Python——第十章Broker（rabbitMQ/redis）

基于RabbitMQ的direct任务驱动异步RPC程序实现：

RPC_dispatcher指令分发器：

 #!/usr/bin/env python
 # -*- coding:utf-8 -*-
 __Author__ = "Zhang Xuyao"

 import pika
 import uuid
 import time
 import threading

 class RpcDispatcher(object):
     def __init__(self, rMQ_addr):
         self.cmd_list = [
             "ls", "df", "free",
             "ip", "ifconfig", "tail",
             "head", "grep", "uptime",
             "date"
         ]
         self.task_dict = {}
         self.task_fin_dict = {}
         self.routing_key_list = []

         self.connection = pika.BlockingConnection(
             pika.ConnectionParameters(host=rMQ_addr)
         )
         self.channel = self.connection.channel()

         # 收数据用
         recv_queue = self.channel.queue_declare(exclusive=True)
         self.recv_queue_name = recv_queue.method.queue
         self.channel.basic_consume(self._on_response, queue=self.recv_queue_name)

         # 发数据用
         self.channel.exchange_declare(exchange='send', type='direct')
         self.send_queue = self.channel.queue_declare()
         self.send_queue_name = self.send_queue.method.queue

     # 获取指定通道的响应(4)###
     def _on_response(self, ch, method, parameters, msg):
         if parameters.correlation_id in self.task_dict:
             self.task_dict[parameters.correlation_id][parameters.app_id]["response"] = msg.decode("utf-8")
             ch.basic_ack(delivery_tag=method.delivery_tag)
             self.task_dict[parameters.correlation_id][parameters.app_id]["recv_time"] = time.time()
             fin_flag = False
             for host in self.task_dict[parameters.correlation_id]:
                 if self.task_dict[parameters.correlation_id][host]["response"] != None:
                     continue
                 else:

                     break
             # 执行结果全部收到就把记录转移到已经完成容器中，根据检查已经完成容器中的内容用于确定任务的状态
             else:
                 self.task_fin_dict[parameters.correlation_id] = self.task_dict[parameters.correlation_id]
                 del self.task_dict[parameters.correlation_id]

     # 发送请求（2）######
     def _on_request(self, input_cmd, host_list):
         print(RpcDispatcher.colorStr("[x]Requesting>>: '%s' on %s"
                                      % (cmd, tuple(host_list)), 33))
         self.response = None
         # 生成全局校验码
         corr_id = str(uuid.uuid4())
         print(RpcDispatcher.colorStr("[x]Task_id>>: %s"
                                      % corr_id, 34))
         self.task_dict[corr_id] = {}
         if host_list:
             for host in host_list:
                 self.task_dict[corr_id][host] = {
                     "cmd": input_cmd,
                     "response": None,
                     "req_time": time.time(),
                     "recv_time": None,
                 }
                 # 绑定routing_key准备并发布消息
                 self.channel.queue_bind(exchange='send',
                                         queue=self.send_queue_name,
                                         routing_key=host)
                 # 向执行器并发布消息指令
                 self.channel.basic_publish(exchange='send',
                                            routing_key=host,
                                            properties=pika.BasicProperties(
                                                reply_to=self.recv_queue_name,
                                                correlation_id=corr_id,
                                            ),
                                            body=str(input_cmd))
                 # 消息发布后解除routing_key绑定
                 self.channel.queue_unbind(exchange='send',
                                           queue=self.send_queue_name,
                                           routing_key=host)

             # 守护线程负责不断检测响应结果是否全部收到
             on_recv_thread = threading.Thread(target=self._on_recv, args=[corr_id, ])
             on_recv_thread.setDaemon(True)
             on_recv_thread.start()

     # 等待数据消息(3)
     def _on_recv(self, task_id):
         # 根据检查已经完成容器中的指定task_id是否存在来确定任务的状态，为空则继续收取消息
         while task_id not in self.task_fin_dict:
             self.connection.process_data_events()

     # 显示已经完成的任务编号（5）
     def show_task_fin(self):
         print("尚未查看的任务：")
         for task_id in self.task_fin_dict:
             value_list = tuple(self.task_fin_dict[task_id].values())
             host_list = tuple(self.task_fin_dict[task_id].keys())
             cmd = str(value_list[0]["cmd"])
             print(RpcDispatcher.colorStr("[task_id]: %s | [cmd_info]: '%s' | [host_list]: %s"
                                          % (task_id, cmd, host_list), 32))

     # 获取指定任务的执行结果（6）
     def get_response(self, task_id):
         if task_id in self.task_fin_dict:
             for host in self.task_fin_dict[task_id]:
                 response = self.task_fin_dict[task_id][host]["response"]
                 cmd_req = self.task_fin_dict[task_id][host]["cmd"]
                 time_cost = self.task_fin_dict[task_id][host]["recv_time"] - \
                             self.task_fin_dict[task_id][host]["req_time"]
                 time_cost = round(time_cost, 3)
                 print(RpcDispatcher.colorStr("Host: %s           | Cmd: '%s' \nTime Cost: %ss | Response: "
                                              % (host, cmd_req, time_cost), 33))
                 print(RpcDispatcher.colorStr(response, 36))
             del self.task_fin_dict[task_id]
         else:
             print("任务结果尚未全部返回")

     # 接收外部输入，调用请求（1）
     def call(self, cmd, host_list):
         return self._on_request(cmd, host_list)

     @staticmethod
     def colorStr(aStr, color_code):
         return "\033[0;" + str(color_code) + ";0m" + aStr + "\033[0m"

     def __del__(self):
         self.connection.close()

 if __name__ == '__main__':
     cmd_rpc = RpcDispatcher(rMQ_addr="localhost")
     while True:
         cmd = input("[$]Cmd>>:")
         if cmd.lower() != 'eof' and cmd.lower() != 'exit':
             if cmd.split()[0].lower() in ["$s"]:
                 cmd_rpc.show_task_fin()
             elif cmd.split()[0].lower() in ["$c"] and len(cmd.split()) == 2:
                 cmd_rpc.get_response(cmd.split()[1])
             else:
                 cmd_split = cmd.split()
                 has_host = cmd_split.count("--hosts")
                 if has_host != 1:
                     print(cmd_rpc.colorStr("Usage <cmd> --hosts <ip1>[,<ip2>[,<ip3>...]]", 35))
                     continue
                 else:
                     if len(cmd_split) <= cmd_split.index("--hosts") + 1:
                         print("请至少指定一个主机IP")
                         continue
                     host_list = cmd_split[cmd_split.index("--hosts") + 1].split(',')
                     cmd = " ".join(cmd_split[0:cmd_split.index("--hosts")]).strip()

                     if cmd.split()[0] in cmd_rpc.cmd_list:
                         cmd_rpc.call(cmd, host_list)
                     else:
                         print("您输入的命令暂不支持...")
                         continue
         else:
             break

RPC 指令分发器代码

RPC_executor指令执行器：

 #!/usr/bin/env python
 # -*- coding:utf-8 -*-
 __Author__ = "Zhang Xuyao"

 import pika
 import os, time

 class RpcExecutor(object):
     def __init__(self, rMQ_addr, ip):
         self.connection = pika.BlockingConnection(pika.ConnectionParameters(
             host=rMQ_addr))
         self.channel = self.connection.channel()

         # 接收命令用
         self.ip = ip
         self.channel.exchange_declare(exchange='send', type='direct')
         self.send_queue = self.channel.queue_declare()
         self.send_queue_name = self.send_queue.method.queue
         self.channel.queue_bind(exchange='send', routing_key=self.ip, queue=self.send_queue_name)
         self.channel.basic_consume(self._on_request, queue=self.send_queue_name)

     # 开始订阅消息
     def run(self):
         print(" [x] Awaiting RPC requests")
         self.channel.start_consuming()

     # 执行消息命令
     def exec_cmd(self, cmd_str):
         result = os.popen(cmd_str).read()
         if not result:
             return "命令没有输出结果"
         else:
             return result

     # 请求事件的回调函数
     def _on_request(self, ch, method, props, body):
         cmd_str = body.decode('utf-8')
         print(" [.] exec_cmd(%s)" % cmd_str)
         response = self.exec_cmd(cmd_str)

         # 发送命令结果，通过传来的queue进行发布，这里的app_id是额外增加的IP信息，区分于其他执行器的响应结果
         ch.basic_publish(exchange='',
                          routing_key=props.reply_to,
                          properties=pika.BasicProperties(
                              correlation_id=props.correlation_id,
                              app_id=self.ip
                          ),
                          body=str(response)
                          )
         # 消息反馈确认，确保对方确实收到了响应结果
         ch.basic_ack(delivery_tag=method.delivery_tag)

     def __del__(self):
         self.connection.close()

 if __name__ == '__main__':
     ip = input('请输入IP地址>>:')
     cmd_executor = RpcExecutor('localhost', ip)
     cmd_executor.run()

RPC 执行器代码