1 # copyright 2003-2010 LOGILAB S.A. (Paris, FRANCE), all rights reserved.

     2 # contact http://www.logilab.fr/ -- mailto:contact@logilab.fr

     3 #

     4 # This file is part of CubicWeb.

     5 #

     6 # CubicWeb is free software: you can redistribute it and/or modify it under the

     7 # terms of the GNU Lesser General Public License as published by the Free

     8 # Software Foundation, either version 2.1 of the License, or (at your option)

     9 # any later version.

    10 #

    11 # CubicWeb is distributed in the hope that it will be useful, but WITHOUT

    12 # ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS

    13 # FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License for more

    14 # details.

    15 #

    16 # You should have received a copy of the GNU Lesser General Public License along

    17 # with CubicWeb.  If not, see <http://www.gnu.org/licenses/>.

    18 """provide class to do Apache rewrite rules'job inside cubicweb (though functionnalities

    19 are much more limited for the moment)

    20 

    21 """

    22 

    23 __docformat__ = "restructuredtext en"

    24 

    25 from re import compile

    26 

    27 from cubicweb.web import Redirect

    28 from cubicweb.web.component import Component

    29 

    30 class RewriteCond(object):

    31     def __init__(self, condition, match='host', rules=(), action='rewrite'):

    32         self.condition = compile(condition)

    33         assert match in ('host', 'path'), match

    34         self.match_part = match

    35         self.rules = []

    36         for rule, replace in rules:

    37             rulergx = compile(rule)

    38             self.rules.append( (rulergx, replace) )

    39         assert action in ('rewrite', 'redirect', 'stop'), action

    40         self.process = getattr(self, 'action_%s' % action)

    41 

    42     def match(self, **kwargs):

    43         self._match = self.condition.match(kwargs[self.match_part])

    44         return not self._match is None

    45 

    46     def action_rewrite(self, path):

    47         for rgx, replace in self.rules:

    48             if not rgx.match(path) is None:

    49                 matchdict = self._match.groupdict() or None

    50                 if not matchdict is None:

    51                     replace = replace % matchdict

    52                 return rgx.sub(replace, path)

    53         return path

    54 

    55     def action_redirect(self, path):

    56         url = self.action_rewrite(path)

    57         raise Redirect(url)

    58 

    59     def action_stop(self, path):

    60         return path

    61 

    62 

    63 class ApacheURLRewrite(Component):

    64     """inherit from this class with actual rules to activate apache style rewriting

    65 

    66     rules should have the form :

    67 

    68     [('condition pattern 1', [('rule1 pattern', 'replace expression'),

    69                               ('rule2 pattern', 'replace expression')],

    70      ('condition pattern 2', [('rule1 pattern', 'replace expression'),

    71                               ('rule2 pattern', 'replace expression')]

    72     ]

    73 

    74     for instance the equivalent of the following apache rules:

    75 

    76         RewriteCond %{HTTP_HOST} ^logilab\.fr

    77         RewriteRule ^/(.*) http://www.logilab.fr/$1 [L,R=301]

    78 

    79         RewriteCond %{HTTP_HOST} ^www\.logilab\.fr

    80         RewriteRule ^/(.*) http://localhost:8080/$1 [L,P]

    81 

    82         RewriteCond %{HTTP_HOST} ^(.+)\.logilab\.fr

    83         RewriteRule ^/(data/.*) http://localhost:8080/$1 [L,P]

    84         RewriteRule ^/(json.*) http://localhost:8080/$1 [L,P]

    85         RewriteRule ^/(.*) http://localhost:8080/m_%1/$1 [L,P]

    86 

    87     could be written (considering that no "host rewritting" is necessary):

    88 

    89       class MyAppRules(ApacheURLRewrite):

    90         rules = [

    91           RewriteCond('logilab\.fr', match='host',

    92                       rules=[('/(.*)', r'http://www.logilab.fr/\1')],

    93                       action='redirect'),

    94           RewriteCond('(www)\.logilab\.fr', match='host', action='stop'),

    95           RewriteCond('/(data|json)/', match='path', action='stop'),

    96           RewriteCond('(?P<cat>.*)\.logilab\.fr', match='host',

    97                       rules=[('/(.*)', r'/m_%(cat)s/\1')]),

    98         ]

    99     """

   100     __abstract__ = True

   101     __regid__ = 'urlrewriter'

   102     rules = []

   103 

   104     def get_rules(self, req):

   105         return self.rules

   106 

   107     def rewrite(self, host, path, req):

   108         for cond in self.get_rules(req):

   109             if cond.match(host=host, path=path):

   110                 return cond.process(path)

   111         return path