Python实现搭建-简单服务器教程

Python动态服务器网页（需要使用WSGI接口），基本实现步骤如下：
1.等待客户端的链接，服务器会收到一个http协议的请求数据报
2.利用正则表达式对这个请求数据报进行解析（请求方式、提取出文件的环境）
3.提取出文件的环境之后，利用截断取片的方法将文件名转化为模块名称
4.使用m = __import__(),就可以得到返回值为m的模块
5.创建一个env字典：其中包含的是请求方式及文件环境等各种的键值对
6.创建一个新的动态脚本，其中定义了application这个函数，必须包含env和start_response的参数（也是服务器里的调用方法）
7.在这个动态脚本中定义状态码status和响应头headers（注意是字典形式，如Content-Type）
8.然后再调用start_response(status,headers)，但是要注意，这个函数在服务器被定义
9.在动态脚本中编写动态执行程序
10.m.appliction的返回值就是回应数据包的body，它的数据头在start_response被整合
11.将数据头与数据body拼接起来，然后发送给客户端，就可显示动态网页

MyWebServer

import socketimport reimport sys from multiprocessing import Processfrom MyWebFramework import Application # 设置静态文件根目录HTML_ROOT_DIR = "./html"WSGI_PYTHON_DIR = "./wsgipython" class HTTPServer(object):    """"""    def __init__(self, application):        """构造函数， application指的是框架的app"""        self.server_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)        self.server_socket.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)        self.app = application     def start(self):        self.server_socket.listen(128)        while True:            client_socket, client_address = self.server_socket.accept()            #print("[%s,%s]用户连接上了" % (client_address[0],client_address[1]))            print("[%s, %s]用户连接上了" % client_address)            handle_client_process = Process(target=self.handle_client, args=(client_socket,))            handle_client_process.start()            client_socket.close()     def start_response(self, status, headers):        """         status = "200 OK"    headers = [        ("Content-Type", "text/plain")    ]    star        """        response_headers = "HTTP/1.1 " + status + "\r\n"        for header in headers:            response_headers += "%s: %s\r\n" % header         self.response_headers = response_headers     def handle_client(self, client_socket):        """处理客户端请求"""        # 获取客户端请求数据        request_data = client_socket.recv(1024)        print("request data:", request_data)        request_lines = request_data.splitlines()        for line in request_lines:            print(line)         # 解析请求报文        # 'GET / HTTP/1.1'        request_start_line = request_lines[0]        # 提取用户请求的文件名        print("*" * 10)        print(request_start_line.decode("utf-8"))        file_name = re.match(r"\w+ +(/[^ ]*) ", request_start_line.decode("utf-8")).group(1)        method = re.match(r"(\w+) +/[^ ]* ", request_start_line.decode("utf-8")).group(1)         env = {            "PATH_INFO": file_name,            "METHOD": method        }        response_body = self.app(env, self.start_response)        response = self.response_headers + "\r\n" + response_body         # 向客户端返回响应数据        client_socket.send(bytes(response, "utf-8"))        # 关闭客户端连接        client_socket.close()     def bind(self, port):        self.server_socket.bind(("", port)) def main():    sys.path.insert(1, WSGI_PYTHON_DIR)    if len(sys.argv) < 2:        sys.exit("python MyWebServer.py Module:app")    # python MyWebServer.py  MyWebFrameWork:app    module_name, app_name = sys.argv[1].split(":")    # module_name = "MyWebFrameWork"    # app_name = "app"    m = __import__(module_name)    app = getattr(m, app_name)    http_server = HTTPServer(app)    # http_server.set_port    http_server.bind(8000)    http_server.start() if __name__ == "__main__":    main()

MyWebFrameWork

import time# from MyWebServer import HTTPServer # 设置静态文件根目录HTML_ROOT_DIR = "./html" class Application(object):    """框架的核心部分，也就是框架的主题程序，框架是通用的"""    def __init__(self, urls):        # 设置路由信息        self.urls = urls     def __call__(self, env, start_response):        path = env.get("PATH_INFO", "/")        # /static/index.html        if path.startswith("/static"):            # 要访问静态文件            file_name = path[7:]            # 打开文件，读取内容            try:                file = open(HTML_ROOT_DIR + file_name, "rb")            except IOError:                # 代表未找到路由信息，404错误                status = "404 Not Found"                headers = []                start_response(status, headers)                return "not found"            else:                file_data = file.read()                file.close()                 status = "200 OK"                headers = []                start_response(status, headers)                return file_data.decode("utf-8")         for url, handler in self.urls:            #("/ctime", show_ctime)            if path == url:                return handler(env, start_response)         # 代表未找到路由信息，404错误        status = "404 Not Found"        headers = []        start_response(status, headers)        return "not found" def show_ctime(env, start_response):    status = "200 OK"    headers = [        ("Content-Type", "text/plain")    ]    start_response(status, headers)    return time.ctime() def say_hello(env, start_response):    status = "200 OK"    headers = [        ("Content-Type", "text/plain")    ]    start_response(status, headers)    return "hello itcast" def say_haha(env, start_response):    status = "200 OK"    headers = [        ("Content-Type", "text/plain")    ]    start_response(status, headers)    return "hello haha" urls = [            ("/", show_ctime),            ("/ctime", show_ctime),            ("/sayhello", say_hello),            ("/sayhaha", say_haha),        ]app = Application(urls)# if __name__ == "__main__":#     urls = [#             ("/", show_ctime),#             ("/ctime", show_ctime),#             ("/sayhello", say_hello),#             ("/sayhaha", say_haha),#         ]#     app = Application(urls)#     http_server = HTTPServer(app)#     http_server.bind(8000)#     http_server.start()