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 class closed(IOError):
  40     def __init__(self):
  41         super(closed, self).__init__("The client has closed the connection.")
  42
  43 cwd = os.getcwd()
  44 def absolutify(path):
  45     if path[0] != '/':
  46         return os.path.join(cwd, path)
  47     return path
  48
  49 def unquoteurl(url):
  50     buf = ""
  51     i = 0
  52     while i < len(url):
  53         c = url[i]
  54         i += 1
  55         if c == '%':
  56             if len(url) >= i + 2:
  57                 c = 0
  58                 if '0' <= url[i] <= '9':
  59                     c |= (ord(url[i]) - ord('0')) << 4
  60                 elif 'a' <= url[i] <= 'f':
  61                     c |= (ord(url[i]) - ord('a') + 10) << 4
  62                 elif 'A' <= url[i] <= 'F':
  63                     c |= (ord(url[i]) - ord('A') + 10) << 4
  64                 else:
  65                     raise ValueError("Illegal URL escape character")
  66                 if '0' <= url[i + 1] <= '9':
  67                     c |= ord(url[i + 1]) - ord('0')
  68                 elif 'a' <= url[i + 1] <= 'f':
  69                     c |= ord(url[i + 1]) - ord('a') + 10
  70                 elif 'A' <= url[i + 1] <= 'F':
  71                     c |= ord(url[i + 1]) - ord('A') + 10
  72                 else:
  73                     raise ValueError("Illegal URL escape character")
  74                 buf += chr(c)
  75                 i += 2
  76             else:
  77                 raise ValueError("Incomplete URL escape character")
  78         else:
  79             buf += c
  80     return buf
  81
  82 def dowsgi(req):
  83     env = {}
  84     env["wsgi.version"] = 1, 0
  85     for key, val in req.headers:
  86         env["HTTP_" + key.upper().replace("-", "_")] = val
  87     env["SERVER_SOFTWARE"] = "ashd-wsgi/1"
  88     env["GATEWAY_INTERFACE"] = "CGI/1.1"
  89     env["SERVER_PROTOCOL"] = req.ver
  90     env["REQUEST_METHOD"] = req.method
  91     env["REQUEST_URI"] = req.url
  92     try:
  93         env["PATH_INFO"] = unquoteurl(req.rest)
  94     except:
  95         env["PATH_INFO"] = req.rest
  96     name = req.url
  97     p = name.find('?')
  98     if p >= 0:
  99         env["QUERY_STRING"] = name[p + 1:]
 100         name = name[:p]
 101     else:
 102         env["QUERY_STRING"] = ""
 103     if name[-len(req.rest):] == req.rest:
 104         name = name[:-len(req.rest)]
 105     env["SCRIPT_NAME"] = name
 106     if "Host" in req: env["SERVER_NAME"] = req["Host"]
 107     if "X-Ash-Server-Port" in req: env["SERVER_PORT"] = req["X-Ash-Server-Port"]
 108     if "X-Ash-Protocol" in req and req["X-Ash-Protocol"] == "https": env["HTTPS"] = "on"
 109     if "X-Ash-Address" in req: env["REMOTE_ADDR"] = req["X-Ash-Address"]
 110     if "Content-Type" in req: env["CONTENT_TYPE"] = req["Content-Type"]
 111     if "Content-Length" in req: env["CONTENT_LENGTH"] = req["Content-Length"]
 112     if "X-Ash-File" in req: env["SCRIPT_FILENAME"] = absolutify(req["X-Ash-File"])
 113     if "X-Ash-Protocol" in req: env["wsgi.url_scheme"] = req["X-Ash-Protocol"]
 114     env["wsgi.input"] = req.sk
 115     env["wsgi.errors"] = sys.stderr
 116     env["wsgi.multithread"] = True
 117     env["wsgi.multiprocess"] = False
 118     env["wsgi.run_once"] = False
 119
 120     resp = []
 121     respsent = []
 122
 123     def flushreq():
 124         if not respsent:
 125             if not resp:
 126                 raise Exception, "Trying to write data before starting response."
 127             status, headers = resp
 128             respsent[:] = [True]
 129             try:
 130                 req.sk.write("HTTP/1.1 %s\n" % status)
 131                 for nm, val in headers:
 132                     req.sk.write("%s: %s\n" % (nm, val))
 133                 req.sk.write("\n")
 134             except IOError:
 135                 raise closed()
 136
 137     def write(data):
 138         if not data:
 139             return
 140         flushreq()
 141         try:
 142             req.sk.write(data)
 143             req.sk.flush()
 144         except IOError:
 145             raise closed()
 146
 147     def startreq(status, headers, exc_info = None):
 148         if resp:
 149             if exc_info:                # Interesting, this...
 150                 try:
 151                     if respsent:
 152                         raise exc_info[0], exc_info[1], exc_info[2]
 153                 finally:
 154                     exc_info = None     # CPython GC bug?
 155             else:
 156                 raise Exception, "Can only start responding once."
 157         resp[:] = status, headers
 158         return write
 159
 160     respiter = handler(env, startreq)
 161     try:
 162         try:
 163             for data in respiter:
 164                 write(data)
 165             if resp:
 166                 flushreq()
 167         except closed:
 168             pass
 169     finally:
 170         if hasattr(respiter, "close"):
 171             respiter.close()
 172
 173 class reqthread(threading.Thread):
 174     def __init__(self, req):
 175         super(reqthread, self).__init__(name = "Request handler")
 176         self.req = req.dup()
 177
 178     def run(self):
 179         try:
 180             dowsgi(self.req)
 181         finally:
 182             self.req.close()
 183
 184 def handle(req):
 185     reqthread(req).start()
 186
 187 ashd.util.serveloop(handle)