python - 使用 python socketserver 如何将变量传递给处理程序类的构造函数

Question

我想将我的数据库连接传递给 EchoHandler 类，但是我完全不知道该怎么做或访问 EchoHandler 类。

class EchoHandler(SocketServer.StreamRequestHandler):    def handle(self):        print self.client_address, 'connected'if __name__ == '__main__':    conn = MySQLdb.connect (host = "10.0.0.5", user = "user", passwd = "pass", db = "database")    SocketServer.ForkingTCPServer.allow_reuse_address = 1    server = SocketServer.ForkingTCPServer(('10.0.0.6', 4242), EchoHandler)    print "Server listening on localhost:4242..."    try:        server.allow_reuse_address        server.serve_forever()    except KeyboardInterrupt:        print "\nbailing..."

Answer 1

不幸的是，没有一种简单的方法可以直接从服务器外部访问处理程序。

您有两个选项可以将信息传递给 EchoHandler 实例:

1. 将连接存储为服务器的属性(在调用 server_forever() 之前添加 server.conn = conn)，然后通过 self.server.conn.
2. 您可以覆盖服务器的 finish_request 并在那里分配值(您必须将其传递给 EchoHandler 的构造函数并覆盖 EchoHandler.__init__)。这是一个更加困惑的解决方案，它几乎需要您将连接存储在服务器上。

我的最佳选择:

class EchoHandler(SocketServer.StreamRequestHandler):
    def handle(self):
        # I have no idea why you would print this but this is an example
        print( self.server.conn );
        print self.client_address, 'connected'

if __name__ == '__main__':
    SocketServer.ForkingTCPServer.allow_reuse_address = 1

    server = SocketServer.ForkingTCPServer(('10.0.0.6', 4242), EchoHandler)
    server.conn = MySQLdb.connect (host = "10.0.0.5", 
                     user = "user", passwd = "pass", db = "database")
    # continue as normal