mediagoblin/tools/template.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 from math import ceil
  18 import jinja2
  19 from babel.localedata import exists
  20 from mediagoblin import mg_globals
  21 from mediagoblin import messages
  22 from mediagoblin.tools import common
  23 from mediagoblin.tools.translate import setup_gettext
  24 from mediagoblin.meddleware.csrf import render_csrf_form_token
  25
  26
  27 SETUP_JINJA_ENVS = {}
  28
  29
  30 def get_jinja_env(template_loader, locale):
  31     """
  32     Set up the Jinja environment,
  33
  34     (In the future we may have another system for providing theming;
  35     for now this is good enough.)
  36     """
  37     setup_gettext(locale)
  38
  39     # If we have a jinja environment set up with this locale, just
  40     # return that one.
  41     if SETUP_JINJA_ENVS.has_key(locale):
  42         return SETUP_JINJA_ENVS[locale]
  43
  44     # jinja2.StrictUndefined will give exceptions on references
  45     # to undefined/unknown variables in templates.
  46     template_env = jinja2.Environment(
  47         loader=template_loader, autoescape=True,
  48         undefined=jinja2.StrictUndefined,
  49         extensions=['jinja2.ext.i18n', 'jinja2.ext.autoescape'])
  50
  51     template_env.install_gettext_callables(
  52         mg_globals.translations.ugettext,
  53         mg_globals.translations.ungettext)
  54
  55     # All templates will know how to ...
  56     # ... fetch all waiting messages and remove them from the queue
  57     # ... construct a grid of thumbnails or other media
  58     # ... have access to the global and app config
  59     template_env.globals['fetch_messages'] = messages.fetch_messages
  60     template_env.globals['gridify_list'] = gridify_list
  61     template_env.globals['gridify_cursor'] = gridify_cursor
  62     template_env.globals['app_config'] = mg_globals.app_config
  63     template_env.globals['global_config'] = mg_globals.global_config
  64
  65     if exists(locale):
  66         SETUP_JINJA_ENVS[locale] = template_env
  67
  68     return template_env
  69
  70
  71 # We'll store context information here when doing unit tests
  72 TEMPLATE_TEST_CONTEXT = {}
  73
  74
  75 def render_template(request, template_path, context):
  76     """
  77     Render a template with context.
  78
  79     Always inserts the request into the context, so you don't have to.
  80     Also stores the context if we're doing unit tests.  Helpful!
  81     """
  82     template = request.template_env.get_template(
  83         template_path)
  84     context['request'] = request
  85     rendered_csrf_token = render_csrf_form_token(request)
  86     if rendered_csrf_token is not None:
  87         context['csrf_token'] = render_csrf_form_token(request)
  88     rendered = template.render(context)
  89
  90     if common.TESTS_ENABLED:
  91         TEMPLATE_TEST_CONTEXT[template_path] = context
  92
  93     return rendered
  94
  95
  96 def clear_test_template_context():
  97     global TEMPLATE_TEST_CONTEXT
  98     TEMPLATE_TEST_CONTEXT = {}
  99
 100
 101 def gridify_list(this_list, num_cols=5):
 102     """
 103     Generates a list of lists where each sub-list's length depends on
 104     the number of columns in the list
 105     """
 106     grid = []
 107
 108     # Figure out how many rows we should have
 109     num_rows = int(ceil(float(len(this_list)) / num_cols))
 110
 111     for row_num in range(num_rows):
 112         slice_min = row_num * num_cols
 113         slice_max = (row_num + 1) * num_cols
 114
 115         row = this_list[slice_min:slice_max]
 116
 117         grid.append(row)
 118
 119     return grid
 120
 121
 122 def gridify_cursor(this_cursor, num_cols=5):
 123     """
 124     Generates a list of lists where each sub-list's length depends on
 125     the number of columns in the list
 126     """
 127     return gridify_list(list(this_cursor), num_cols)