向python套接字服务器发送命令和参数

Question

我目前正在设置一个服务器，其中包含以下内容：

try:
    while 1:
        #wait to accept a connection - blocking call
        conn, addr = s.accept()
        print time.ctime() + ' Connection from: ' + addr[0] + ':' + str(addr[1])
        #start new thread takes 1st argument as a function name to be run, second is the tuple of arguments to the function.
        start_new_thread(shreddingclient ,(conn,))

except KeyboardInterrupt:
    print "Exiting gracefully anyway"
finally:
    s.close()

我还在想，能够向服务器def shredding client发送命令和参数也会很好。

我搜索了很多，并在客户端上找到了类似的东西。

def send_data(self, com, arg):
       content={"command": com, "arg": arg}
       return json.dumps(content)

我的问题是：

def shreddingclient将如何接受命令，即执行其他def的参数？

(这是为了避免shreddingclient将是一个巨大的if/elif函数)

Answer 1

假设您只要求在从json接收命令并将其解码为dict之后才发出命令，则可以使用另一个dict将命令名映射到实现这些命令的函数。在这里，msg是传递给shredderclient的解码消息dict。

def command1(msg):
    print(msg['arg'])

def command2(msg):
    print(msg['arg'])

dispatch_table = {'command1':command1, 'command2':command2}

def process_message(msg):
    try:
        cmd = dispatch_table[msg['command']]
    except KeyError:
        print('invalid command')
        return None
    cmd(msg)

Answer 2

如果使用dispatcher，一个简单的示例如下：

dispatcher = {'command_1': func_1,
              'command_2': func_2,
              ...}

当你收到数据时：

data = json.loads(content)
command = data['command']
args, kwargs = data['args'], data['kwargs']
try:
    res = dispatcher[command](*args, **kwargs)
except KeyError:
    print "Unknown command"