Python套接字问题:无论使用什么浏览器,如何获取可靠的POST数据?

时间:2020-03-06 15:04:53  来源:igfitidea点击:

我编写了带有套接字模块的小型Python + Ajax程序(最后列出),以研究COMET异步通信的概念。

这个想法是允许浏览器通过我的python程序彼此实时发送消息。

诀窍是让" GET messages / ..."连接打开,等待消息回复。

我的问题主要在于通过socket.recv获得的可靠性...

当我从Firefox发布时,它运行良好。

当我从Chrome或者IE进行发布时,我在Python中获得的"数据"为空。

有人知道浏览器之间的这个问题吗?

是某些浏览器注入了一些EOF还是其他字符杀死了" recv"的接收?

有什么解决方案可以解决此问题吗?

Python中的server.py:

import socket
connected={}
def inRequest(text):
   content=''
   if text[0:3]=='GET':
      method='GET'
   else:
      method='POST'
      k=len(text)-1
      while k>0 and text[k]!='\n' and text[k]!='\r':
         k=k-1
      content=text[k+1:]
   text=text[text.index(' ')+1:]
   url=text[:text.index(' ')]
   return {"method":method,"url":url,"content":content}

mySocket = socket.socket ( socket.AF_INET, socket.SOCK_STREAM )
mySocket.bind ( ( '', 80 ) )
mySocket.listen ( 10 )
while True:
   channel, details = mySocket.accept()
   data=channel.recv(4096)
   req=inRequest(data)
   url=req["url"]
   if url=="/client.html" or url=="/clientIE.html":
      f=open('C:\async\'+url)
      channel.send ('HTTP/1.1 200 OK\n\n'+f.read())
      f.close()
      channel.close()
   elif '/messages' in url:
      if req["method"]=='POST':
         target=url[10:]
         if target in connected:
            connected[target].send("HTTP/1.1 200 OK\n\n"+req["content"])
            print req["content"]+" sent to "+target
            connected[target].close()
            channel.close()
      elif req["method"]=='GET':
         user=url[10:]
         connected[user]=channel
         print user+' is connected'

HTML + Javascript中的client.html:

<html>
<head>
    <script>
        var user=''
        function post(el) {
            if (window.XMLHttpRequest) {
                var text=el.value;
                var req=new XMLHttpRequest();
                el.value='';
                var target=document.getElementById('to').value
            }
            else if (window.ActiveXObject) {
                var text=el.content;
                var req=new ActiveXObject("Microsoft.XMLHTTP");
                el.content='';
            }
            else 
                return;
            req.open('POST','messages/'+target,true)
            req.send(text);
        }
        function get(u) {
            if (user=='')
                user=u.value
            var req=new XMLHttpRequest()
            req.open('GET','messages/'+user,true)
            req.onload=function() {
                var message=document.createElement('p');
                message.innerHTML=req.responseText;
                document.getElementById('messages').appendChild(message);
                get(user);
            }
            req.send(null)
        }
    </script>
</head>
<body>
<span>From</span>
<input id="user"/>
<input type="button" value="sign in" onclick="get(document.getElementById('user'))"/>
<span>To</span>
<input id="to"/>
<span>:</span>
<input id="message"/>

<input type="button" value="post" onclick="post(document.getElementById('message'))"/>
<div id="messages">
</div>
</body>
</html>

解决方案

我建议在客户端使用JS / Ajax库,以消除代码中跨浏览器问题的可能性。出于同样的原因,如果前者不允许进行低级控制,我建议我们使用python HTTP服务器库(例如SimpleHTTPServer或者Twisted的东西)。

另一个想法是使用Wireshark之​​类的东西来检查浏览器发送的内容。

你的问题是

  • tcp套接字处理读取的数据不应该足够
  • http处理不完整

我推荐以下讲座:

  • rfc2616
  • 史蒂文斯的套接字网络API

请参阅以下示例,了解可以处理帖子的正常工作的http服务器

index = '''
<html>
    <head>
    </head>
    <body>
        <form action="/" method="POST">
            <textarea name="foo"></textarea>
            <button type="submit">post</button>
        </form>
        <h3>data posted</h3>
        <div>
            %s
        </div>
    </body>
</html>
'''

bufsize = 4048
import socket
import re
from urlparse import urlparse

class Headers(object):
    def __init__(self, headers):
        self.__dict__.update(headers)

    def __getitem__(self, name):
        return getattr(self, name)

    def get(self, name, default=None):
        return getattr(self, name, default)

class Request(object):
    header_re = re.compile(r'([a-zA-Z-]+):? ([^\r]+)', re.M)

    def __init__(self, sock):
        header_off = -1
        data = ''
        while header_off == -1:
            data += sock.recv(bufsize)
            header_off = data.find('\r\n\r\n')
        header_string = data[:header_off]
        self.content = data[header_off+4:]

        lines = self.header_re.findall(header_string)
        self.method, path = lines.pop(0)
        path, protocol = path.split(' ')
        self.headers = Headers(
            (name.lower().replace('-', '_'), value)
            for name, value in lines
        )

        if self.method in ['POST', 'PUT']:
            content_length = int(self.headers.get('content_length', 0))
            while len(self.content) <  content_length:
                self.content += sock.recv(bufsize)

        self.query = urlparse(path)[4]

acceptor = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
acceptor.setsockopt(
    socket.SOL_SOCKET,
    socket.SO_REUSEADDR,
    1,
)
acceptor.bind(('', 2501 ))
acceptor.listen(10)

if __name__ == '__main__':
    while True:
        sock, info = acceptor.accept()
        request = Request(sock)
        sock.send('HTTP/1.1 200 OK\n\n' + (index % request.content) )
        sock.close()

非常感谢Florian,代码正在运行!!!!
我重复使用了模板,并使用我的COMET机制完成了主模板,并且效果更好
Chrome和Firefox运作良好
IE仍存在"长GET"系统问题
当它收到GET的答案时,它不会停止重新执行循环以打印消息。
现在调查问题

这是我针对非常基本的JQuery + Python跨浏览器系统的更新代码。

Python程序,基于Florian的代码:

bufsize = 4048
import socket
import re
from urlparse import urlparse
connected={}
class Headers(object):
    def __init__(self, headers):
        self.__dict__.update(headers)

    def __getitem__(self, name):
        return getattr(self, name)

    def get(self, name, default=None):
        return getattr(self, name, default)

class Request(object):
    header_re = re.compile(r'([a-zA-Z-]+):? ([^\r]+)', re.M)

    def __init__(self, sock):
        header_off = -1
        data = ''
        while header_off == -1:
            data += sock.recv(bufsize)
            header_off = data.find('\r\n\r\n')
        header_string = data[:header_off]
        self.content = data[header_off+4:]
        furl=header_string[header_string.index(' ')+1:]
        self.url=furl[:furl.index(' ')]
        lines = self.header_re.findall(header_string)
        self.method, path = lines.pop(0)
        path, protocol = path.split(' ')
        self.headers = Headers(
            (name.lower().replace('-', '_'), value)
            for name, value in lines
        )
        if self.method in ['POST', 'PUT']:
            content_length = int(self.headers.get('content_length', 0))
            while len(self.content) <  content_length:
                self.content += sock.recv(bufsize)
        self.query = urlparse(path)[4]

acceptor = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
acceptor.setsockopt(
    socket.SOL_SOCKET,
    socket.SO_REUSEADDR,
    1,
)
acceptor.bind(('', 8007 ))
acceptor.listen(10)

if __name__ == '__main__':
    while True:
        sock, info = acceptor.accept()
        request = Request(sock)
        m=request.method
        u=request.url[1:]
        if m=='GET' and (u=='client.html' or u=='jquery.js'):
            f=open('c:\async\'+u,'r')
            sock.send('HTTP/1.1 200 OK\n\n'+f.read())
            f.close()
            sock.close()
        elif 'messages' in u:
            if m=='POST':
                target=u[9:]
                if target in connected:
                    connected[target].send("HTTP/1.1 200 OK\n\n"+request.content)
                    connected[target].close()
                    sock.close()
            elif m=='GET':
                user=u[9:]
                connected[user]=sock
                print user+' is connected'

然后将带有Jquery的HTML压缩:

<html>
<head>
    <style>
        input {width:80px;}
        span {font-size:12px;}
        button {font-size:10px;}
    </style>
    <script type="text/javascript" src='jquery.js'></script>
    <script>
        var user='';
        function post(el) {$.post('messages/'+$('#to').val(),$('#message').val());}
        function get(u) {
            if (user=='') user=u.value
            $.get('messages/'+user,function(data) { $("<p>"+data+"</p>").appendTo($('#messages'));get(user);});
        }
    </script>
</head>
<body>
<span>From</span><input id="user"/><button onclick="get(document.getElementById('user'))">log</button>
<span>To</span><input id="to"/>
<span>:</span><input id="message"/><button onclick="post()">post</button>
<div id="messages"></div>
</body>
</html>