华为云速建站模板,创建网站的费用,html登录注册页面代码,网站建设应用程序开发SocketServer 中非常重要的两个基类就是#xff1a;BaseServer 和 BaseRequestHandler在SocketServer 中也提供了对TCP以及UDP的高级封装#xff0c;这次我们主要通过分析关于TCP的处理逻辑来对SocketServer模块进行一个很好的理解和学习 TCPServer TCPServer 继承了BaseServ…SocketServer 中非常重要的两个基类就是BaseServer 和 BaseRequestHandler在SocketServer 中也提供了对TCP以及UDP的高级封装这次我们主要通过分析关于TCP的处理逻辑来对SocketServer模块进行一个很好的理解和学习 TCPServer TCPServer 继承了BaseServer初始化的时候进行了socket套接字的创建。 def __init__(self, server_address, RequestHandlerClass, bind_and_activateTrue):Constructor. May be extended, do not override.BaseServer.__init__(self, server_address, RequestHandlerClass)self.socket socket.socket(self.address_family,self.socket_type)if bind_and_activate:try:self.server_bind()self.server_activate()except:self.server_close()raise 在这里我们看到了我们非常熟悉的关于socket的创建的内容self.socket socket.socket(self.address_family, self.socket_type)通过socket模块创建了socket对象接着调用了server_bind和server_activate server_bind 源码内容如下 def server_bind(self):Called by constructor to bind the socket.May be overridden.if self.allow_reuse_address:self.socket.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)self.socket.bind(self.server_address)self.server_address self.socket.getsockname() 这里我们看到了非常熟悉的操作socket.bind方法以及设置了socket的相关属性 server_activate 源码内容如下 def server_activate(self):Called by constructor to activate the server.May be overridden.self.socket.listen(self.request_queue_size) 同样的这里的调用也非常简单就是执行了socket.listen get_request 在TCPServer类中我们还看到了get_request方法源码内容如下 def get_request(self):Get the request and client address from the socket.May be overridden.return self.socket.accept() 这个的调用其实我们可以在BaseServer这个基类中看到我们之前看过关于BaseServer中这个基类的源码我们可以从我们调用BaseServer基类中的serve_forever方法查看这里是调用了_handle_request_noblock方法我继续查看_handle_request_noblock这个源码 def _handle_request_noblock(self):Handle one request, without blocking.I assume that selector.select() has returned that the socket isreadable before this function was called, so there should be no risk ofblocking in get_request().try:request, client_address self.get_request()except OSError:returnif self.verify_request(request, client_address):try:self.process_request(request, client_address)except:self.handle_error(request, client_address)self.shutdown_request(request)else:self.shutdown_request(request) 可以看到这里最后是调用了process_request来处理请求继续查看源码 def process_request(self, request, client_address):Call finish_request.Overridden by ForkingMixIn and ThreadingMixIn.self.finish_request(request, client_address)self.shutdown_request(request)def finish_request(self, request, client_address):Finish one request by instantiating RequestHandlerClass.self.RequestHandlerClass(request, client_address, self) 从上面的代码我们可以到最后是在finish_request中实例化了RequestHandlerClass我们 这个时候查看一下BaseRequestHandler这个基类的源码如下: class BaseRequestHandler:Base class for request handler classes.This class is instantiated for each request to be handled. Theconstructor sets the instance variables request, client_addressand server, and then calls the handle() method. To implement aspecific service, all you need to do is to derive a class whichdefines a handle() method.The handle() method can find the request as self.request, theclient address as self.client_address, and the server (in case itneeds access to per-server information) as self.server. Since aseparate instance is created for each request, the handle() methodcan define other arbitrary instance variables.def __init__(self, request, client_address, server):self.request requestself.client_address client_addressself.server serverself.setup()try:self.handle()finally:self.finish()def setup(self):passdef handle(self):passdef finish(self):pass 在初始化函数里我们看到了调用setup()方法这setup在StreamRequestHandler会被重写 StreamRequestHandler TCPServer实现了使用tcp套接字的网络服务Handler方面则是对应的StreamRequestHandler。它继承了BaseRequestHandler。基类的setup方法和finish方法被它重写用于通过连接实现缓存文件的读写操作。 setup方法 源码内容如下 def setup(self):self.connection self.requestif self.timeout is not None:self.connection.settimeout(self.timeout)if self.disable_nagle_algorithm:self.connection.setsockopt(socket.IPPROTO_TCP,socket.TCP_NODELAY, True)self.rfile self.connection.makefile(rb, self.rbufsize)self.wfile self.connection.makefile(wb, self.wbufsize) 这里主要设置了对应连接的属性其中创建了两个对象非常重要:一个可读rfile和一个可写wfile的“文件”对象但是实际并不是创建了文件而是封装了读取数据和发送数据的操作抽象成了对文件的操作可以理解self.rfile 就是读取客户端数据的对象它有一些方法可以读取数据。self.wfile则是用来发送数据给客户端的对象。 整理流程(TCP) 实现TCP服务需要使用TCPServer和StreamRequestHandler共同协作 转载于:https://www.cnblogs.com/zhaof/p/8890600.html
