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 dowsgi(req):
  46     env = {}
  47     env["wsgi.version"] = 1, 0
  48     for key, val in req.headers:
  49         env["HTTP_" + key.upper().replace("-", "_")] = val
  50     env["SERVER_SOFTWARE"] = "ashd-wsgi/1"
  51     env["GATEWAY_INTERFACE"] = "CGI/1.1"
  52     env["SERVER_PROTOCOL"] = req.ver
  53     env["REQUEST_METHOD"] = req.method
  54     env["REQUEST_URI"] = req.url
  55     env["PATH_INFO"] = req.rest
  56     name = req.url
  57     p = name.find('?')
  58     if p >= 0:
  59         env["QUERY_STRING"] = name[p + 1:]
  60         name = name[:p]
  61     else:
  62         env["QUERY_STRING"] = ""
  63     if name[-len(req.rest):] == req.rest:
  64         name = name[:-len(req.rest)]
  65     env["SCRIPT_NAME"] = name
  66     if "Host" in req: env["SERVER_NAME"] = req["Host"]
  67     if "X-Ash-Server-Port" in req: env["SERVER_PORT"] = req["X-Ash-Server-Port"]
  68     if "X-Ash-Protocol" in req and req["X-Ash-Protocol"] == "https": env["HTTPS"] = "on"
  69     if "X-Ash-Address" in req: env["REMOTE_ADDR"] = req["X-Ash-Address"]
  70     if "Content-Type" in req: env["CONTENT_TYPE"] = req["Content-Type"]
  71     if "Content-Length" in req: env["CONTENT_LENGTH"] = req["Content-Length"]
  72     if "X-Ash-File" in req: env["SCRIPT_FILENAME"] = absolutify(req["X-Ash-File"])
  73     if "X-Ash-Protocol" in req: env["wsgi.url_scheme"] = req["X-Ash-Protocol"]
  74     env["wsgi.input"] = req.sk
  75     env["wsgi.errors"] = sys.stderr
  76     env["wsgi.multithread"] = True
  77     env["wsgi.multiprocess"] = False
  78     env["wsgi.run_once"] = False
  79
  80     resp = []
  81     respsent = []
  82
  83     def flushreq():
  84         if not respsent:
  85             if not resp:
  86                 raise Exception, "Trying to write data before starting response."
  87             status, headers = resp
  88             respsent[:] = [True]
  89             req.sk.write("HTTP/1.1 %s\n" % status)
  90             for nm, val in headers:
  91                 req.sk.write("%s: %s\n" % (nm, val))
  92             req.sk.write("\n")
  93
  94     def write(data):
  95         if not data:
  96             return
  97         flushreq()
  98         req.sk.write(data)
  99         req.sk.flush()
 100
 101     def startreq(status, headers, exc_info = None):
 102         if resp:
 103             if exc_info:                # Interesting, this...
 104                 try:
 105                     if respsent:
 106                         raise exc_info[0], exc_info[1], exc_info[2]
 107                 finally:
 108                     exc_info = None     # CPython GC bug?
 109             else:
 110                 raise Exception, "Can only start responding once."
 111         resp[:] = status, headers
 112         return write
 113
 114     respiter = handler(env, startreq)
 115     try:
 116         for data in respiter:
 117             write(data)
 118         if resp:
 119             flushreq()
 120     finally:
 121         if hasattr(respiter, "close"):
 122             respiter.close()
 123
 124 class reqthread(threading.Thread):
 125     def __init__(self, req):
 126         super(reqthread, self).__init__(name = "Request handler")
 127         self.req = req.dup()
 128
 129     def run(self):
 130         try:
 131             dowsgi(self.req)
 132         finally:
 133             self.req.close()
 134
 135 def handle(req):
 136     reqthread(req).start()
 137
 138 ashd.util.serveloop(handle)