mediagoblin/tools/response.py

   1 # GNU MediaGoblin -- federated, autonomous media hosting
   2 # Copyright (C) 2011, 2012 MediaGoblin contributors.  See AUTHORS.
   3 #
   4 # This program is free software: you can redistribute it and/or modify
   5 # it under the terms of the GNU Affero General Public License as published by
   6 # the Free Software Foundation, either version 3 of the License, or
   7 # (at your option) any later version.
   8 #
   9 # This program is distributed in the hope that it will be useful,
  10 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 # GNU Affero General Public License for more details.
  13 #
  14 # You should have received a copy of the GNU Affero General Public License
  15 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
  16
  17 import werkzeug.utils
  18 from werkzeug.wrappers import Response as wz_Response
  19 from mediagoblin.tools.template import render_template
  20 from mediagoblin.tools.translate import (lazy_pass_to_ugettext as _,
  21                                          pass_to_ugettext)
  22 from mediagoblin.db.models import UserBan, User
  23 from datetime import datetime
  24
  25 class Response(wz_Response):
  26     """Set default response mimetype to HTML, otherwise we get text/plain"""
  27     default_mimetype = u'text/html'
  28
  29
  30 def render_to_response(request, template, context, status=200):
  31     """Much like Django's shortcut.render()"""
  32     return Response(
  33         render_template(request, template, context),
  34         status=status)
  35
  36
  37 def render_error(request, status=500, title=_('Oops!'),
  38                  err_msg=_('An error occured')):
  39     """Render any error page with a given error code, title and text body
  40
  41     Title and description are passed through as-is to allow html. Make
  42     sure no user input is contained therein for security reasons. The
  43     description will be wrapped in <p></p> tags.
  44     """
  45     return Response(render_template(request, 'mediagoblin/error.html',
  46         {'err_code': status, 'title': title, 'err_msg': err_msg}),
  47         status=status)
  48
  49
  50 def render_403(request):
  51     """Render a standard 403 page"""
  52     _ = pass_to_ugettext
  53     title = _('Operation not allowed')
  54     err_msg = _("Sorry Dave, I can't let you do that!</p><p>You have tried "
  55                 " to perform a function that you are not allowed to. Have you "
  56                 "been trying to delete all user accounts again?")
  57     return render_error(request, 403, title, err_msg)
  58
  59 def render_404(request):
  60     """Render a standard 404 page."""
  61     _ = pass_to_ugettext
  62     err_msg = _("There doesn't seem to be a page at this address. Sorry!</p>"
  63                 "<p>If you're sure the address is correct, maybe the page "
  64                 "you're looking for has been moved or deleted.")
  65     return render_error(request, 404, err_msg=err_msg)
  66
  67 def render_user_banned(request):
  68     """Renders the page which tells a user they have been banned, for how long
  69     and the reason why they have been banned"
  70     """
  71     user_ban = UserBan.query.get(request.user.id)
  72     if datetime.now()>user_ban.expiration_date:
  73         user_ban.delete()
  74         redirect(request,
  75             'mediagoblin.index')
  76     return render_to_response(request,
  77         'mediagoblin/banned.html',
  78         {'reason':user_ban.reason,
  79          'expiration_date':user_ban.expiration_date})
  80
  81 def render_http_exception(request, exc, description):
  82     """Return Response() given a werkzeug.HTTPException
  83
  84     :param exc: werkzeug.HTTPException or subclass thereof
  85     :description: message describing the error."""
  86     # If we were passed the HTTPException stock description on
  87     # exceptions where we have localized ones, use those:
  88     stock_desc = (description == exc.__class__.description)
  89
  90     if stock_desc and exc.code == 403:
  91         return render_403(request)
  92     elif stock_desc and exc.code == 404:
  93         return render_404(request)
  94
  95     return render_error(request, title=exc.args[0],
  96                         err_msg=description,
  97                         status=exc.code)
  98
  99
 100 def redirect(request, *args, **kwargs):
 101     """Redirects to an URL, using urlgen params or location string
 102
 103     :param querystring: querystring to be appended to the URL
 104     :param location: If the location keyword is given, redirect to the URL
 105     """
 106     querystring = kwargs.pop('querystring', None)
 107
 108     # Redirect to URL if given by "location=..."
 109     if 'location' in kwargs:
 110         location = kwargs.pop('location')
 111     else:
 112         location = request.urlgen(*args, **kwargs)
 113
 114     if querystring:
 115         location += querystring
 116     return werkzeug.utils.redirect(location)
 117
 118
 119 def redirect_obj(request, obj):
 120     """Redirect to the page for the given object.
 121
 122     Requires obj to have a .url_for_self method."""
 123     return redirect(request, location=obj.url_for_self(request.urlgen))