Python 为什么我的简单CGI服务器不能处理AJAX Post请求？

通过遵循教程，我创建了自己的CGI python服务器脚本（服务于端口8000）。如果我想从python脚本生成web页面，或者提供本机HTML页面，但当我发出AJAX POST请求时，服务器工作得很好？

如果我向python文件aaa.py发出AJAX请求（使用下面的javascript），我的服务器将打印以下错误文本：

代码501，消息只能发布到CGI脚本
“POST/aaa.py HTTP/1.1”501-

您认为我需要做什么才能允许python cgi服务器允许/处理AJAX请求？

我的CGI服务器：

__version__ = "0.4"

__all__ = ["CGIHTTPRequestHandler"]

import os
import sys
import urllib
import BaseHTTPServer
import SimpleHTTPServer
import select


class CGIHTTPRequestHandler(SimpleHTTPServer.SimpleHTTPRequestHandler):

    """Complete HTTP server with GET, HEAD and POST commands.

    GET and HEAD also support running CGI scripts.

    The POST command is *only* implemented for CGI scripts.

    """

    # Determine platform specifics
    have_fork = hasattr(os, 'fork')
    have_popen2 = hasattr(os, 'popen2')
    have_popen3 = hasattr(os, 'popen3')

    # pretend we don't have these to force execution in process
    have_fork = 0

    # Make rfile unbuffered -- we need to read one line and then pass
    # the rest to a subprocess, so we can't use buffered input.
    rbufsize = 0

    def do_POST(self):
        """Serve a POST request.

        This is only implemented for CGI scripts.

        """

        if self.is_cgi():
            self.run_cgi()
        else:
            self.send_error(501, "Can only POST to CGI scripts")

    def send_head(self):
        """Version of send_head that support CGI scripts"""
        if self.is_cgi():
            return self.run_cgi()
        else:
            return SimpleHTTPServer.SimpleHTTPRequestHandler.send_head(self)

    def is_cgi(self):
        """Test whether self.path corresponds to a CGI script.

        Return a tuple (dir, rest) if self.path requires running a
        CGI script, None if not.  Note that rest begins with a
        slash if it is not empty.

        The default implementation tests whether the path
        begins with one of the strings in the list
        self.cgi_directories (and the next character is a '/'
        or the end of the string).

        """

        path = self.path

        for x in self.cgi_directories:
            i = len(x)
            if path[:i] == x and (not path[i:] or path[i] == '/'):
                self.cgi_info = path[:i], path[i+1:]
                return True
        return False

    cgi_directories = ['/cgi-bin', '/htbin']

    def is_executable(self, path):
        """Test whether argument path is an executable file."""
        return executable(path)

    def is_python(self, path):
        """Test whether argument path is a Python script."""
        head, tail = os.path.splitext(path)
        return tail.lower() in (".py", ".pyw")

    def run_cgi(self):
        """Execute a CGI script."""
        dir, rest = self.cgi_info
        i = rest.rfind('?')
        if i >= 0:
            rest, query = rest[:i], rest[i+1:]
        else:
            query = ''
#         i = rest.find('/')
#         if i >= 0:
#             script, rest = rest[:i], rest[i:]
#         else:
#             script, rest = rest, ''
        script = rest

        scriptname = dir + '/' + script

        scriptfile = self.translate_path(scriptname)
        if not os.path.exists(scriptfile):
            self.send_error(404, "No such CGI script (%s)" % `scriptname`)
            return
        if not os.path.isfile(scriptfile):
            self.send_error(403, "CGI script is not a plain file (%s)" %
                            `scriptname`)
            return
        ispy = self.is_python(scriptname)
        if not ispy:
            if not (self.have_fork or self.have_popen2 or self.have_popen3):
                self.send_error(403, "CGI script is not a Python script (%s)" %
                                `scriptname`)
                return
            if not self.is_executable(scriptfile):
                self.send_error(403, "CGI script is not executable (%s)" %
                                `scriptname`)
                return

        # Reference: http://hoohoo.ncsa.uiuc.edu/cgi/env.html
        # XXX Much of the following could be prepared ahead of time!
        env = {}
        env['SERVER_SOFTWARE'] = self.version_string()
        env['SERVER_NAME'] = self.server.server_name
        env['GATEWAY_INTERFACE'] = 'CGI/1.1'
        env['SERVER_PROTOCOL'] = self.protocol_version
        env['SERVER_PORT'] = str(self.server.server_port)
        env['REQUEST_METHOD'] = self.command
        uqrest = urllib.unquote(rest)
        env['PATH_INFO'] = uqrest
        env['PATH_TRANSLATED'] = self.translate_path(uqrest)
        env['SCRIPT_NAME'] = scriptname
        if query:
            env['QUERY_STRING'] = query
        host = self.address_string()
        if host != self.client_address[0]:
            env['REMOTE_HOST'] = host
        env['REMOTE_ADDR'] = self.client_address[0]
        # XXX AUTH_TYPE
        # XXX REMOTE_USER
        # XXX REMOTE_IDENT
        if self.headers.typeheader is None:
            env['CONTENT_TYPE'] = self.headers.type
        else:
            env['CONTENT_TYPE'] = self.headers.typeheader
        length = self.headers.getheader('content-length')
        if length:
            env['CONTENT_LENGTH'] = length
        accept = []
        for line in self.headers.getallmatchingheaders('accept'):
            if line[:1] in "\t\n\r ":
                accept.append(line.strip())
            else:
                accept = accept + line[7:].split(',')
        env['HTTP_ACCEPT'] = ','.join(accept)
        ua = self.headers.getheader('user-agent')
        if ua:
            env['HTTP_USER_AGENT'] = ua
        co = filter(None, self.headers.getheaders('cookie'))
        if co:
            env['HTTP_COOKIE'] = ', '.join(co)

        # XXX Other HTTP_* headers
        if not self.have_fork:
            # Since we're setting the env in the parent, provide empty
            # values to override previously set values
            for k in ('QUERY_STRING', 'REMOTE_HOST', 'CONTENT_LENGTH',
                      'HTTP_USER_AGENT'):
###, 'HTTP_COOKIE' -- removed by S.
                env.setdefault(k, "")

#         for key in env.keys():
#             print key +  " '" + env[key] + "'"

        os.environ.update(env)

        self.send_response(200, "Script output follows")

        decoded_query = query.replace('+', ' ')

        if self.have_fork:
            # Unix -- fork as we should
            args = [script]
            if '=' not in decoded_query:
                args.append(decoded_query)
            nobody = nobody_uid()
            self.wfile.flush() # Always flush before forking
            pid = os.fork()
            if pid != 0:
                # Parent
                pid, sts = os.waitpid(pid, 0)
                # throw away additional data [see bug #427345]
                while select.select([self.rfile], [], [], 0)[0]:
                    if not self.rfile.read(1):
                        break
                if sts:
                    self.log_error("CGI script exit status %#x", sts)
                return
            # Child
            try:
                try:
                    os.setuid(nobody)
                except os.error:
                    pass
                os.dup2(self.rfile.fileno(), 0)
                os.dup2(self.wfile.fileno(), 1)
                os.execve(scriptfile, args, os.environ)
            except:
                self.server.handle_error(self.request, self.client_address)
                os._exit(127)

        elif self.have_popen2 or self.have_popen3:
            # Windows -- use popen2 or popen3 to create a subprocess
            import shutil
            if self.have_popen3:
                popenx = os.popen3
            else:
                popenx = os.popen2
            cmdline = scriptfile
            if self.is_python(scriptfile):
                interp = sys.executable
                if interp.lower().endswith("w.exe"):
                    # On Windows, use python.exe, not pythonw.exe
                    interp = interp[:-5] + interp[-4:]
                cmdline = "%s -u \"%s\"" % (interp, cmdline)
            if '=' not in query and '"' not in query:
                cmdline = '%s "%s"' % (cmdline, query)
            self.log_message("command: %s", cmdline)
            try:
                nbytes = int(length)
            except (TypeError, ValueError):
                nbytes = 0
            files = popenx(cmdline, 'b')
            fi = files[0]
            fo = files[1]
            if self.have_popen3:
                fe = files[2]
            if self.command.lower() == "post" and nbytes > 0:
                data = self.rfile.read(nbytes)
                fi.write(data)
            # throw away additional data [see bug #427345]
            while select.select([self.rfile._sock], [], [], 0)[0]:
                if not self.rfile._sock.recv(1):
                    break
            fi.close()
            shutil.copyfileobj(fo, self.wfile)
            if self.have_popen3:
                errors = fe.read()
                fe.close()
                if errors:
                    self.log_error('%s', errors)
            sts = fo.close()
            if sts:
                self.log_error("CGI script exit status %#x", sts)
            else:
                self.log_message("CGI script exited OK")

        else:
            # Other O.S. -- execute script in this process
            save_argv = sys.argv
            save_stdin = sys.stdin
            save_stdout = sys.stdout
            save_stderr = sys.stderr
            try:
                try:
                    sys.argv = [scriptfile]
                    if '=' not in decoded_query:
                        sys.argv.append(decoded_query)
                    sys.stdout = self.wfile
                    sys.stdin = self.rfile
                    execfile(scriptfile, {"__name__": "__main__"})
                finally:
                    sys.argv = save_argv
                    sys.stdin = save_stdin
                    sys.stdout = save_stdout
                    sys.stderr = save_stderr
            except SystemExit, sts:
                self.log_error("CGI script exit status %s", str(sts))
            else:
                self.log_message("CGI script exited OK")


nobody = None

def nobody_uid():
    """Internal routine to get nobody's uid"""
    global nobody
    if nobody:
        return nobody
    try:
        import pwd
    except ImportError:
        return -1
    try:
        nobody = pwd.getpwnam('nobody')[2]
    except KeyError:
        nobody = 1 + max(map(lambda x: x[2], pwd.getpwall()))
    return nobody


def executable(path):
    """Test for executable file."""
    try:
        st = os.stat(path)
    except os.error:
        return False
    return st.st_mode & 0111 != 0


def test(HandlerClass = CGIHTTPRequestHandler,
         ServerClass = BaseHTTPServer.HTTPServer):
    SimpleHTTPServer.test(HandlerClass, ServerClass)


if __name__ == '__main__':
    test()

aaa.py中的代码：

#!/usr/bin/env python

import cgitb; cgitb.enable()
import cgi
import os

print "Content-Type: text/html\n"

input_data   = cgi.FieldStorage()
print "hello"

我的AJAX/Javascript：

function onTest( dest, params )             
    {                 
        var xmlhttp;                  

        if (window.XMLHttpRequest)                 
        {// code for IE7+, Firefox, Chrome, Opera, Safari                     
            xmlhttp=new XMLHttpRequest();                 
        }                 
        else                 
        {// code for IE6, IE5                     
            xmlhttp=new ActiveXObject("Microsoft.XMLHTTP");                 
        }                  

        xmlhttp.onreadystatechange=function()                 
        {                     
            if (xmlhttp.readyState==4 && xmlhttp.status==200)                     
            {                         
                document.getElementById( "bb" ).innerHTML = xmlhttp.responseText;                     
            }                 
        }                  

        xmlhttp.open("POST",dest,true);                 
        xmlhttp.setRequestHeader("Content-type","application/x-www-form-urlencoded");                 
        xmlhttp.send( params );              
    } 

---

当您使用python http cgi服务器时，cgi脚本必须位于subdir（来自您的服务器脚本）/cgi-bin

下，这里的大多数人不想通过长代码列表来解决您的问题。因此，试着隔离问题并发布相关的10（-20）行代码。通过这种方式，您通常会自己找到解决方案。或者提高有用答案的概率。可能的重复