mvc框架打造笔记之wsgi协议的优缺点以及接口实现

#xiaorui.cc
 
import socket
import StringIO
import sys
 
class WSGIServer(object):
 
 address_family = socket.AF_INET
 socket_type = socket.SOCK_STREAM
 request_queue_size = 1
 
 def __init__(self, server_address):
  # 创建一个可用的socket
  self.listen_socket = listen_socket = socket.socket(
   self.address_family,
   self.socket_type
  )
  #socket的工作模式
  listen_socket.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
  # Bind
  listen_socket.bind(server_address) #绑定地址
  # Activate
  listen_socket.listen(self.request_queue_size) #监听文件描述符
  # Get server host name and port
  host, port = self.listen_socket.getsockname()[:2]
  self.server_name = socket.getfqdn(host)
  self.server_port = port
  self.headers_set = []
 
 def set_app(self, application):
  self.application = application
 
 def serve_forever(self): #启动WSGI server服务，不停的监听并获取socket数据。
  listen_socket = self.listen_socket
  while True:
    self.client_connection, client_address = listen_socket.accept()
   self.handle_one_request() #处理新连接
 
 def handle_one_request(self): #主要处理函数
  self.request_data = request_data = self.client_connection.recv(1024)
  print(''.join(
   '< {line}\n'.format(line=line)
   for line in request_data.splitlines()
  ))
 
  self.parse_request(request_data)
  env = self.get_environ()
 
  #给flask\tornado传递两个参数，environ，start_response
  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): #处理socket的http协议
  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): #获取environ数据
  env = {}
  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
  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_info=None): #创建回调函数.
  server_headers = [
   ('Date', 'Tue, 31 Mar 2015 12:54:48 GMT'),
   ('Server', 'WSGIServer 0.3'),
  ]
  self.headers_set = [status, response_headers + server_headers]
 
 def finish_response(self, result): #把application返回给WSGI的数据返回给客户端。
  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) = '', 8888
 
def make_server(server_address, application):
 server = WSGIServer(server_address)
 server.set_app(application)
 return server
 
if __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) #动态加载模块
 application = getattr(module, application) #使用自省的模式加载application的WSGI协议入口。
 httpd = make_server(SERVER_ADDRESS, application)
 print('WSGIServer: Serving HTTP on port {port} ...\n'.format(port=PORT))
 httpd.serve_forever()

#xiaorui.cc
from flask import Flask
from flask import Response
flask_app = Flask('flaskapp')
 
@flask_app.route('/search')
def hello_world():
 return Response(
  'xiaorui.cc Golang vs python !\n',
  mimetype='text/plain'
 )
 
app = flask_app.wsgi_app

python webserver2.py flaskapp:app