Comply better with the CGI specification by unquoting PATH_INFO.
[ashd.git] / 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')) << 4
58                 elif 'A' <= url[i] <= 'F':
59                     c |= (ord(url[i]) - ord('A')) << 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')
66                 elif 'A' <= url[i + 1] <= 'F':
67                     c |= ord(url[i + 1]) - ord('A')
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
78 def dowsgi(req):
79     env = {}
80     env["wsgi.version"] = 1, 0
81     for key, val in req.headers:
82         env["HTTP_" + key.upper().replace("-", "_")] = val
83     env["SERVER_SOFTWARE"] = "ashd-wsgi/1"
84     env["GATEWAY_INTERFACE"] = "CGI/1.1"
85     env["SERVER_PROTOCOL"] = req.ver
86     env["REQUEST_METHOD"] = req.method
87     env["REQUEST_URI"] = req.url
88     try:
89         env["PATH_INFO"] = unquoteurl(req.rest)
90     except:
91         env["PATH_INFO"] = req.rest
92     name = req.url
93     p = name.find('?')
94     if p >= 0:
95         env["QUERY_STRING"] = name[p + 1:]
96         name = name[:p]
97     else:
98         env["QUERY_STRING"] = ""
99     if name[-len(req.rest):] == req.rest:
100         name = name[:-len(req.rest)]
101     env["SCRIPT_NAME"] = name
102     if "Host" in req: env["SERVER_NAME"] = req["Host"]
103     if "X-Ash-Server-Port" in req: env["SERVER_PORT"] = req["X-Ash-Server-Port"]
104     if "X-Ash-Protocol" in req and req["X-Ash-Protocol"] == "https": env["HTTPS"] = "on"
105     if "X-Ash-Address" in req: env["REMOTE_ADDR"] = req["X-Ash-Address"]
106     if "Content-Type" in req: env["CONTENT_TYPE"] = req["Content-Type"]
107     if "Content-Length" in req: env["CONTENT_LENGTH"] = req["Content-Length"]
108     if "X-Ash-File" in req: env["SCRIPT_FILENAME"] = absolutify(req["X-Ash-File"])
109     if "X-Ash-Protocol" in req: env["wsgi.url_scheme"] = req["X-Ash-Protocol"]
110     env["wsgi.input"] = req.sk
111     env["wsgi.errors"] = sys.stderr
112     env["wsgi.multithread"] = True
113     env["wsgi.multiprocess"] = False
114     env["wsgi.run_once"] = False
115
116     resp = []
117     respsent = []
118
119     def flushreq():
120         if not respsent:
121             if not resp:
122                 raise Exception, "Trying to write data before starting response."
123             status, headers = resp
124             respsent[:] = [True]
125             req.sk.write("HTTP/1.1 %s\n" % status)
126             for nm, val in headers:
127                 req.sk.write("%s: %s\n" % (nm, val))
128             req.sk.write("\n")
129
130     def write(data):
131         if not data:
132             return
133         flushreq()
134         req.sk.write(data)
135         req.sk.flush()
136
137     def startreq(status, headers, exc_info = None):
138         if resp:
139             if exc_info:                # Interesting, this...
140                 try:
141                     if respsent:
142                         raise exc_info[0], exc_info[1], exc_info[2]
143                 finally:
144                     exc_info = None     # CPython GC bug?
145             else:
146                 raise Exception, "Can only start responding once."
147         resp[:] = status, headers
148         return write
149
150     respiter = handler(env, startreq)
151     try:
152         for data in respiter:
153             write(data)
154         if resp:
155             flushreq()
156     finally:
157         if hasattr(respiter, "close"):
158             respiter.close()
159
160 class reqthread(threading.Thread):
161     def __init__(self, req):
162         super(reqthread, self).__init__(name = "Request handler")
163         self.req = req.dup()
164     
165     def run(self):
166         try:
167             dowsgi(self.req)
168         finally:
169             self.req.close()
170     
171 def handle(req):
172     reqthread(req).start()
173
174 ashd.util.serveloop(handle)