hgweb: give ErrorResponse a descriptive string/Exception representation

Very handy if the exception should appear in output.

mercurial/hgweb/common.py

@@ -1,164 +1,163 b''
 # hgweb/common.py - Utility functions needed by hgweb_mod and hgwebdir_mod
 #
 # Copyright 21 May 2005 - (c) 2005 Jake Edge <[e-mail]>
 # Copyright 2005, 2006 Matt Mackall <[e-mail]>
 #
 # This software may be used and distributed according to the terms of the
 # GNU General Public License version 2 or any later version.
 
 import errno, mimetypes, os
 
 HTTP_OK = 200
 HTTP_NOT_MODIFIED = 304
 HTTP_BAD_REQUEST = 400
 HTTP_UNAUTHORIZED = 401
 HTTP_FORBIDDEN = 403
 HTTP_NOT_FOUND = 404
 HTTP_METHOD_NOT_ALLOWED = 405
 HTTP_SERVER_ERROR = 500
 
 # Hooks for hgweb permission checks; extensions can add hooks here. Each hook
 # is invoked like this: hook(hgweb, request, operation), where operation is
 # either read, pull or push. Hooks should either raise an ErrorResponse
 # exception, or just return.
 # It is possible to do both authentication and authorization through this.
 permhooks = []
 
 def checkauthz(hgweb, req, op):
     '''Check permission for operation based on request data (including
     authentication info). Return if op allowed, else raise an ErrorResponse
     exception.'''
 
     user = req.env.get('REMOTE_USER')
 
     deny_read = hgweb.configlist('web', 'deny_read')
     if deny_read and (not user or deny_read == ['*'] or user in deny_read):
         raise ErrorResponse(HTTP_UNAUTHORIZED, 'read not authorized')
 
     allow_read = hgweb.configlist('web', 'allow_read')
     result = (not allow_read) or (allow_read == ['*'])
     if not (result or user in allow_read):
         raise ErrorResponse(HTTP_UNAUTHORIZED, 'read not authorized')
 
     if op == 'pull' and not hgweb.allowpull:
         raise ErrorResponse(HTTP_UNAUTHORIZED, 'pull not authorized')
     elif op == 'pull' or op is None: # op is None for interface requests
         return
 
     # enforce that you can only push using POST requests
     if req.env['REQUEST_METHOD'] != 'POST':
         msg = 'push requires POST request'
         raise ErrorResponse(HTTP_METHOD_NOT_ALLOWED, msg)
 
     # require ssl by default for pushing, auth info cannot be sniffed
     # and replayed
     scheme = req.env.get('wsgi.url_scheme')
     if hgweb.configbool('web', 'push_ssl', True) and scheme != 'https':
         raise ErrorResponse(HTTP_OK, 'ssl required')
 
     deny = hgweb.configlist('web', 'deny_push')
     if deny and (not user or deny == ['*'] or user in deny):
         raise ErrorResponse(HTTP_UNAUTHORIZED, 'push not authorized')
 
     allow = hgweb.configlist('web', 'allow_push')
     result = allow and (allow == ['*'] or user in allow)
     if not result:
         raise ErrorResponse(HTTP_UNAUTHORIZED, 'push not authorized')
 
 # Add the default permhook, which provides simple authorization.
 permhooks.append(checkauthz)
 
 
 class ErrorResponse(Exception):
     def __init__(self, code, message=None, headers=[]):
-        Exception.__init__(self)
+        if message is None:
+            message = _statusmessage(code)
+        Exception.__init__(self, code, message)
         self.code = code
+        self.message = message
         self.headers = headers
-        if message is not None:
-            self.message = message
-        else:
-            self.message = _statusmessage(code)
 
 def _statusmessage(code):
     from BaseHTTPServer import BaseHTTPRequestHandler
     responses = BaseHTTPRequestHandler.responses
     return responses.get(code, ('Error', 'Unknown error'))[0]
 
 def statusmessage(code, message=None):
     return '%d %s' % (code, message or _statusmessage(code))
 
 def get_mtime(spath):
     cl_path = os.path.join(spath, "00changelog.i")
     if os.path.exists(cl_path):
         return os.stat(cl_path).st_mtime
     else:
         return os.stat(spath).st_mtime
 
 def staticfile(directory, fname, req):
     """return a file inside directory with guessed Content-Type header
 
     fname always uses '/' as directory separator and isn't allowed to
     contain unusual path components.
     Content-Type is guessed using the mimetypes module.
     Return an empty string if fname is illegal or file not found.
 
     """
     parts = fname.split('/')
     for part in parts:
         if (part in ('', os.curdir, os.pardir) or
             os.sep in part or os.altsep is not None and os.altsep in part):
             return ""
     fpath = os.path.join(*parts)
     if isinstance(directory, str):
         directory = [directory]
     for d in directory:
         path = os.path.join(d, fpath)
         if os.path.exists(path):
             break
     try:
         os.stat(path)
         ct = mimetypes.guess_type(path)[0] or "text/plain"
         req.respond(HTTP_OK, ct, length = os.path.getsize(path))
         fp = open(path, 'rb')
         data = fp.read()
         fp.close()
         return data
     except TypeError:
         raise ErrorResponse(HTTP_SERVER_ERROR, 'illegal filename')
     except OSError, err:
         if err.errno == errno.ENOENT:
             raise ErrorResponse(HTTP_NOT_FOUND)
         else:
             raise ErrorResponse(HTTP_SERVER_ERROR, err.strerror)
 
 def paritygen(stripecount, offset=0):
     """count parity of horizontal stripes for easier reading"""
     if stripecount and offset:
         # account for offset, e.g. due to building the list in reverse
         count = (stripecount + offset) % stripecount
         parity = (stripecount + offset) / stripecount & 1
     else:
         count = 0
         parity = 0
     while True:
         yield parity
         count += 1
         if stripecount and count >= stripecount:
             parity = 1 - parity
             count = 0
 
 def get_contact(config):
     """Return repo contact information or empty string.
 
     web.contact is the primary source, but if that is not set, try
     ui.username or $EMAIL as a fallback to display something useful.
     """
     return (config("web", "contact") or
             config("ui", "username") or
             os.environ.get("EMAIL") or "")
 
 def caching(web, req):
     tag = str(web.mtime)
     if req.env.get('HTTP_IF_NONE_MATCH') == tag:
         raise ErrorResponse(HTTP_NOT_MODIFIED)
     req.headers.append(('ETag', tag))