python/ashd-wsgi

   1 #!/usr/bin/python
   2
   3 import sys, os, getopt, threading
   4 import ashd.proto, ashd.util
   5
   6 def usage(out):
   7     out.write("usage: ashd-wsgi [-hA] [-p MODPATH] HANDLER-MODULE [ARGS...]\n")
   8
   9 modwsgi_compat = False
  10 opts, args = getopt.getopt(sys.argv[1:], "+hAp:")
  11 for o, a in opts:
  12     if o == "-h":
  13         usage(sys.stdout)
  14         sys.exit(0)
  15     elif o == "-p":
  16         sys.path.insert(0, a)
  17     elif o == "-A":
  18         modwsgi_compat = True
  19 if len(args) < 1:
  20     usage(sys.stderr)
  21     sys.exit(1)
  22
  23 try:
  24     handlermod = __import__(args[0], fromlist = ["dummy"])
  25 except ImportError, exc:
  26     sys.stderr.write("ashd-wsgi: handler %s not found: %s\n" % (args[0], exc.message))
  27     sys.exit(1)
  28 if not modwsgi_compat:
  29     if not hasattr(handlermod, "wmain"):
  30         sys.stderr.write("ashd-wsgi: handler %s has no `wmain' function\n" % args[0])
  31         sys.exit(1)
  32     handler = handlermod.wmain(*args[1:])
  33 else:
  34     if not hasattr(handlermod, "application"):
  35         sys.stderr.write("ashd-wsgi: handler %s has no `application' object\n" % args[0])
  36         sys.exit(1)
  37     handler = handlermod.application
  38
  39 cwd = os.getcwd()
  40 def absolutify(path):
  41     if path[0] != '/':
  42         return os.path.join(cwd, path)
  43     return path
  44
  45 def unquoteurl(url):
  46     buf = ""
  47     i = 0
  48     while i < len(url):
  49         c = url[i]
  50         i += 1
  51         if c == '%':
  52             if len(url) >= i + 2:
  53                 c = 0
  54                 if '0' <= url[i] <= '9':
  55                     c |= (ord(url[i]) - ord('0')) << 4
  56                 elif 'a' <= url[i] <= 'f':
  57                     c |= (ord(url[i]) - ord('a') + 10) << 4
  58                 elif 'A' <= url[i] <= 'F':
  59                     c |= (ord(url[i]) - ord('A') + 10) << 4
  60                 else:
  61                     raise ValueError("Illegal URL escape character")
  62                 if '0' <= url[i + 1] <= '9':
  63                     c |= ord(url[i + 1]) - ord('0')
  64                 elif 'a' <= url[i + 1] <= 'f':
  65                     c |= ord(url[i + 1]) - ord('a') + 10
  66                 elif 'A' <= url[i + 1] <= 'F':
  67                     c |= ord(url[i + 1]) - ord('A') + 10
  68                 else:
  69                     raise ValueError("Illegal URL escape character")
  70                 buf += chr(c)
  71                 i += 2
  72             else:
  73                 raise ValueError("Incomplete URL escape character")
  74         else:
  75             buf += c
  76     return buf
  77 def dowsgi(req):
  78     env = {}
  79     env["wsgi.version"] = 1, 0
  80     for key, val in req.headers:
  81         env["HTTP_" + key.upper().replace("-", "_")] = val
  82     env["SERVER_SOFTWARE"] = "ashd-wsgi/1"
  83     env["GATEWAY_INTERFACE"] = "CGI/1.1"
  84     env["SERVER_PROTOCOL"] = req.ver
  85     env["REQUEST_METHOD"] = req.method
  86     env["REQUEST_URI"] = req.url
  87     try:
  88         env["PATH_INFO"] = unquoteurl(req.rest)
  89     except:
  90         env["PATH_INFO"] = req.rest
  91     name = req.url
  92     p = name.find('?')
  93     if p >= 0:
  94         env["QUERY_STRING"] = name[p + 1:]
  95         name = name[:p]
  96     else:
  97         env["QUERY_STRING"] = ""
  98     if name[-len(req.rest):] == req.rest:
  99         name = name[:-len(req.rest)]
 100     env["SCRIPT_NAME"] = name
 101     if "Host" in req: env["SERVER_NAME"] = req["Host"]
 102     if "X-Ash-Server-Port" in req: env["SERVER_PORT"] = req["X-Ash-Server-Port"]
 103     if "X-Ash-Protocol" in req and req["X-Ash-Protocol"] == "https": env["HTTPS"] = "on"
 104     if "X-Ash-Address" in req: env["REMOTE_ADDR"] = req["X-Ash-Address"]
 105     if "Content-Type" in req: env["CONTENT_TYPE"] = req["Content-Type"]
 106     if "Content-Length" in req: env["CONTENT_LENGTH"] = req["Content-Length"]
 107     if "X-Ash-File" in req: env["SCRIPT_FILENAME"] = absolutify(req["X-Ash-File"])
 108     if "X-Ash-Protocol" in req: env["wsgi.url_scheme"] = req["X-Ash-Protocol"]
 109     env["wsgi.input"] = req.sk
 110     env["wsgi.errors"] = sys.stderr
 111     env["wsgi.multithread"] = True
 112     env["wsgi.multiprocess"] = False
 113     env["wsgi.run_once"] = False
 114
 115     resp = []
 116     respsent = []
 117
 118     def flushreq():
 119         if not respsent:
 120             if not resp:
 121                 raise Exception, "Trying to write data before starting response."
 122             status, headers = resp
 123             respsent[:] = [True]
 124             req.sk.write("HTTP/1.1 %s\n" % status)
 125             for nm, val in headers:
 126                 req.sk.write("%s: %s\n" % (nm, val))
 127             req.sk.write("\n")
 128
 129     def write(data):
 130         if not data:
 131             return
 132         flushreq()
 133         req.sk.write(data)
 134         req.sk.flush()
 135
 136     def startreq(status, headers, exc_info = None):
 137         if resp:
 138             if exc_info:                # Interesting, this...
 139                 try:
 140                     if respsent:
 141                         raise exc_info[0], exc_info[1], exc_info[2]
 142                 finally:
 143                     exc_info = None     # CPython GC bug?
 144             else:
 145                 raise Exception, "Can only start responding once."
 146         resp[:] = status, headers
 147         return write
 148
 149     respiter = handler(env, startreq)
 150     try:
 151         for data in respiter:
 152             write(data)
 153         if resp:
 154             flushreq()
 155     finally:
 156         if hasattr(respiter, "close"):
 157             respiter.close()
 158
 159 class reqthread(threading.Thread):
 160     def __init__(self, req):
 161         super(reqthread, self).__init__(name = "Request handler")
 162         self.req = req.dup()
 163
 164     def run(self):
 165         try:
 166             dowsgi(self.req)
 167         finally:
 168             self.req.close()
 169
 170 def handle(req):
 171     reqthread(req).start()
 172
 173 ashd.util.serveloop(handle)