wsgi-未完待续

基于python自定义wsgi框架

import urllib.parse
import http.client
from wsgiref.headers import Headers
from wsgiref.simple_server import make_server
import re


class Request:
    """
    实现对request的封装.
    """

    def __init__(self, environ):
        self.environ = environ
        path_info = environ.get('PATH_INFO')
        self.path = path_info

    @property
    def args(self):
        """把url地址传递过来的query转化成字典"""
        # 拿到environ中的QUERY_STRING.然后利用urllib对其进行解析
        # self.environ['QUERY_STRING'] name=egon&age=12&age=23
        get_arguments = urllib.parse.parse_qs(self.environ['QUERY_STRING'])  # {'name': ['egon'], 'age': ['12', '23']}
        res = {k: v[0] for k, v in get_arguments.items()}  # {'name': 'egon', 'age': '12'}
        return res


class Response:
    """
    实现对response的封装
    """

    def __init__(self, response=None, status=200, charset='utf8', content_type='text/html'):
        self.response = [] if response is None else response  # 响应的内容
        self.charset = charset
        self.headers = Headers()
        # 响应头
        content_type = '{content_type};charset={charset}'.format(content_type=content_type, charset=charset)
        self.headers.add_header('content-type', content_type)
        self._status = status

    @property
    def status(self):
        status_string = http.client.responses.get(self._status, 'UNKNOWN')
        print(status_string)  # OK
        return '{status} {status_string}'.format(status=self._status, status_string=status_string)

    def __iter__(self):
        for val in self.response:
            if isinstance(val, bytes):
                yield val
            else:
                yield val.encode(self.charset)


# 开始写路由系统

class NotFoundError(Exception):
    """ url pattern not found """
    pass


class Router:
    def __init__(self):
        self.routing_table = []  # 保存url pattern 和可调用对象

    def add_route(self, pattern, callback):
        self.routing_table.append((pattern, callback))

    def match(self, path):
        for (pattern, callback) in self.routing_table:
            m = re.match(pattern, path)
            if m:
                # print(callback, m.groups())
                return callback, m.groups()
        raise NotFoundError()

    def __call__(self, pattern):
        def inner(func):
            self.routing_table.append((pattern, func))

        return inner


routes = Router()


def hello(request, name):
    return Response(f"
Hello,{name}
")


def goodbye(request, name):
    return Response(f"
Goodbye,{name}
")


routes.add_route(r'/hello/(.*)', hello)
routes.add_route(r'/goodbye/(.*)$', goodbye)


@routes(r'/world/(.*)')
def world(request, name):
    return Response(f"
Call方法,{name}
")


def request_response_application(func):
    def inner(environ, start_response):
        request = Request(environ)
        response = func(request)  # response是Response的实例
        # start_response 有两个参数,一个是响应的状态,一个是响应头
        # status = '200 OK'
        # headers = [('Content-Type', 'text/html; charset=utf8')]
        print(response.status, response.headers.items)
        start_response(response.status, response.headers.items())
        return iter(response)  # 调用response的__iter__方法

    return inner


@request_response_application
def application(request):
    try:
        callback, args = routes.match(request.path)
        response = callback(request, *args)
    except NotFoundError:
        response = Response("
未发现此页面
", status=404)
    return response

    # name = request.args.get('name', 'default_name')
    # return Response(['
hello {name}
'.format(name=name)])


if __name__ == '__main__':
    httpd = make_server('127.0.0.1', 8999, application)
    httpd.serve_forever()