import socketimport StringIOimport sysclass WSGIServer(object):    address_family = socket.AF_INET    socket_type = socket.SOCK_STREAM    request_queue_size = 1    def __init__(self, server_address):        # Create a listening socket        self.listen_socket = listen_socket = socket.socket(            self.address_family,            self.socket_type            )        # Allow to reuse the same address        listen_socket.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)        # Bind        listen_socket.bind(server_address)        # Active        listen_socket.listen(self.request_queue_size)        # Get server host name and port        host, port = self.listen_socket.getsockname()[0:2]        self.server_name = socket.getfqdn(host)        self.server_port = port        # Return headers set by web framework/Web application        self.headers_set = []    def set_app(self, application):        self.application = application            def serve_forever(self):        listen_socket = self.listen_socket        while True:            # New client connection            self.client_connection, client_address = listen_socket.accept()            # Handle one request and close the client connection. Then            # loop over to wait for another client connection            self.handle_one_request()    def handle_one_request(self):        self.request_data = request_data = http://www.mamicode.com/self.client_connection.recv(1024)        # Print formatted request data a la ‘curl -v‘        print(‘‘.join(            ‘< {line} \n‘.format(line=line)            for line in request_data.splitlines()            ))        self.parse_request(request_data)        # Construct environment dictionary using requst data        env = self.get_environ()        # It‘s time to call our application callable and get        # back a result that will become HTTP response body        print ‘self.application: ********************‘, self.application        result = self.application(env, self.start_response)        # Construct a response and send it back to the client        self.finish_response(result)    def parse_request(self, text):        request_line = text.splitlines()[0]        request_line = request_line.rstrip(‘\r\n‘)        # Break down the request line into components        (self.request_method, #GET         self.path, #/hello         self.request_version # HTTP/1.1         ) = request_line.split()    def get_environ(self):        env = {}        # The following code snippet does not follow PEP8 conventions        # but it‘s formatted the way it is for demonstration purposes        # to emphasize the required variables and their values        #        # Required WSGI variables        env[‘wsgi.version‘]      = (1, 0)        env[‘wsgi.url_scheme‘]   = ‘http‘        env[‘wsgi.input‘]        = StringIO.StringIO(self.request_data)        env[‘wsgi.errors‘]       = sys.stderr        env[‘wsgi.multithread‘]  = False        env[‘wsgi.multiprocess‘] = False        env[‘wsgi.run_once‘]     = False        # Required CGI variables        env[‘REQUEST_METHOD‘]    = self.request_method    # GET        env[‘PATH_INFO‘]         = self.path              # /hello        env[‘SERVER_NAME‘]       = self.server_name       # localhost        env[‘SERVER_PORT‘]       = str(self.server_port)  # 8888        return env    def start_response(self, status, response_headers, exc_onfo=None):        # Add necessary server headers        server_headers = [            (‘Date‘, ‘Tue, 31 Mar 2015 12:54:48 GMT‘),            (‘Server‘, ‘WSGIServer 02‘),            ]        self.headers_set = [status, response_headers + server_headers]        # To adhere to WSGI specification the start_response must return        # a ‘write‘ callable. We simplicity‘s sake we‘ll ignore that detail        # for now.        # return self.finish_response    def finish_response(self, result):        try:            status, response_headers = self.headers_set            response = ‘HTTP/1.1 {status}\r\n‘.format(status=status)            for header in response_headers:                response += ‘{0}: {1}\r\n‘.format(*header)            response += ‘\r\n‘            for data in result:                response += data            # Print formatted response data a la ‘curl -v‘            print(‘‘.join(                ‘> {line}\n‘.format(line=line)                for line in response.splitlines()                ))            self.client_connection.sendall(response)        finally:            self.client_connection.close()SERVER_ADDRESS = (HOST, PORT) = ‘‘, 8888def make_server(server_address, application):    server = WSGIServer(server_address)    server.set_app(application)    return serverif __name__ == ‘__main__‘:    if len(sys.argv) < 2:        sys.exit(‘Provide a WSGI application object as module:callable‘)    app_path = sys.argv[1]    module, application = app_path.split(‘:‘)    module = __import__(module)    application = getattr(module, application)    httpd = make_server(SERVER_ADDRESS, application)    httpd.serve_forever()    print("WSGIServer: Serving HTTP on port {port}...\n".format(port=PORT))

def app(environ, start_response):    """ A barebones WSGI application.    This is a starting point for you own Web Framework :)    """    status = ‘200 OK‘    response_headers = [(‘Content-Type‘, ‘text/plain‘)]    start_response(status, response_headers)    return [‘Hello world from a simple WSGI application!\n‘]

python webserver.py wsgiapp:app