mediagoblin/app.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 os
  18 import logging
  19
  20 from mediagoblin.routing import get_url_map
  21 from mediagoblin.tools.routing import endpoint_to_controller
  22
  23 from werkzeug.wrappers import Request
  24 from werkzeug.exceptions import HTTPException
  25 from werkzeug.routing import RequestRedirect
  26
  27 from mediagoblin import meddleware, __version__
  28 from mediagoblin.db.util import check_db_up_to_date
  29 from mediagoblin.tools import common, session, translate, template
  30 from mediagoblin.tools.response import render_http_exception
  31 from mediagoblin.tools.theme import register_themes
  32 from mediagoblin.tools import request as mg_request
  33 from mediagoblin.media_types.tools import media_type_warning
  34 from mediagoblin.mg_globals import setup_globals
  35 from mediagoblin.init.celery import setup_celery_from_config
  36 from mediagoblin.init.plugins import setup_plugins
  37 from mediagoblin.init import (get_jinja_loader, get_staticdirector,
  38     setup_global_and_app_config, setup_locales, setup_workbench, setup_database,
  39     setup_storage)
  40 from mediagoblin.tools.pluginapi import PluginManager, hook_transform
  41 from mediagoblin.tools.crypto import setup_crypto
  42 from mediagoblin.auth.tools import check_auth_enabled, no_auth_logout
  43
  44
  45 _log = logging.getLogger(__name__)
  46
  47
  48 class MediaGoblinApp(object):
  49     """
  50     WSGI application of MediaGoblin
  51
  52     ... this is the heart of the program!
  53     """
  54     def __init__(self, config_path, setup_celery=True):
  55         """
  56         Initialize the application based on a configuration file.
  57
  58         Arguments:
  59          - config_path: path to the configuration file we're opening.
  60          - setup_celery: whether or not to setup celery during init.
  61            (Note: setting 'celery_setup_elsewhere' also disables
  62            setting up celery.)
  63         """
  64         _log.info("GNU MediaGoblin %s main server starting", __version__)
  65         _log.debug("Using config file %s", config_path)
  66         ##############
  67         # Setup config
  68         ##############
  69
  70         # Open and setup the config
  71         global_config, app_config = setup_global_and_app_config(config_path)
  72
  73         media_type_warning()
  74
  75         setup_crypto()
  76
  77         ##########################################
  78         # Setup other connections / useful objects
  79         ##########################################
  80
  81         # Setup Session Manager, not needed in celery
  82         self.session_manager = session.SessionManager()
  83
  84         # load all available locales
  85         setup_locales()
  86
  87         # Set up plugins -- need to do this early so that plugins can
  88         # affect startup.
  89         _log.info("Setting up plugins.")
  90         setup_plugins()
  91
  92         # Set up the database
  93         self.db = setup_database(app_config['run_migrations'])
  94
  95         # Quit app if need to run dbupdate
  96         ## NOTE: This is currently commented out due to session errors..
  97         ##  We'd like to re-enable!
  98         # check_db_up_to_date()
  99
 100         # Register themes
 101         self.theme_registry, self.current_theme = register_themes(app_config)
 102
 103         # Get the template environment
 104         self.template_loader = get_jinja_loader(
 105             app_config.get('local_templates'),
 106             self.current_theme,
 107             PluginManager().get_template_paths()
 108             )
 109
 110         # Check if authentication plugin is enabled and respond accordingly.
 111         self.auth = check_auth_enabled()
 112         if not self.auth:
 113             app_config['allow_comments'] = False
 114
 115         # Set up storage systems
 116         self.public_store, self.queue_store = setup_storage()
 117
 118         # set up routing
 119         self.url_map = get_url_map()
 120
 121         # set up staticdirector tool
 122         self.staticdirector = get_staticdirector(app_config)
 123
 124         # Setup celery, if appropriate
 125         if setup_celery and not app_config.get('celery_setup_elsewhere'):
 126             if os.environ.get('CELERY_ALWAYS_EAGER', 'false').lower() == 'true':
 127                 setup_celery_from_config(
 128                     app_config, global_config,
 129                     force_celery_always_eager=True)
 130             else:
 131                 setup_celery_from_config(app_config, global_config)
 132
 133         #######################################################
 134         # Insert appropriate things into mediagoblin.mg_globals
 135         #
 136         # certain properties need to be accessed globally eg from
 137         # validators, etc, which might not access to the request
 138         # object.
 139         #######################################################
 140
 141         setup_globals(app=self)
 142
 143         # Workbench *currently* only used by celery, so this only
 144         # matters in always eager mode :)
 145         setup_workbench()
 146
 147         # instantiate application meddleware
 148         self.meddleware = [common.import_component(m)(self)
 149                            for m in meddleware.ENABLED_MEDDLEWARE]
 150
 151     def call_backend(self, environ, start_response):
 152         request = Request(environ)
 153
 154         # Compatibility with django, use request.args preferrably
 155         request.GET = request.args
 156
 157         ## Routing / controller loading stuff
 158         map_adapter = self.url_map.bind_to_environ(request.environ)
 159
 160         # By using fcgi, mediagoblin can run under a base path
 161         # like /mediagoblin/. request.path_info contains the
 162         # path inside mediagoblin. If the something needs the
 163         # full path of the current page, that should include
 164         # the basepath.
 165         # Note: urlgen and routes are fine!
 166         request.full_path = environ["SCRIPT_NAME"] + request.path
 167         # python-routes uses SCRIPT_NAME. So let's use that too.
 168         # The other option would be:
 169         # request.full_path = environ["SCRIPT_URL"]
 170
 171         # Fix up environ for urlgen
 172         # See bug: https://bitbucket.org/bbangert/routes/issue/55/cache_hostinfo-breaks-on-https-off
 173         if environ.get('HTTPS', '').lower() == 'off':
 174             environ.pop('HTTPS')
 175
 176         ## Attach utilities to the request object
 177         # Do we really want to load this via middleware?  Maybe?
 178         session_manager = self.session_manager
 179         request.session = session_manager.load_session_from_cookie(request)
 180         # Attach self as request.app
 181         # Also attach a few utilities from request.app for convenience?
 182         request.app = self
 183
 184         request.db = self.db
 185         request.staticdirect = self.staticdirector
 186
 187         request.locale = translate.get_locale_from_request(request)
 188         request.template_env = template.get_jinja_env(
 189             self.template_loader, request.locale)
 190
 191         def build_proxy(endpoint, **kw):
 192             try:
 193                 qualified = kw.pop('qualified')
 194             except KeyError:
 195                 qualified = False
 196
 197             return map_adapter.build(
 198                     endpoint,
 199                     values=dict(**kw),
 200                     force_external=qualified)
 201
 202         request.urlgen = build_proxy
 203
 204         # Log user out if authentication_disabled
 205         no_auth_logout(request)
 206
 207         mg_request.setup_user_in_request(request)
 208
 209         request.controller_name = None
 210         try:
 211             found_rule, url_values = map_adapter.match(return_rule=True)
 212             request.matchdict = url_values
 213         except RequestRedirect as response:
 214             # Deal with 301 responses eg due to missing final slash
 215             return response(environ, start_response)
 216         except HTTPException as exc:
 217             # Stop and render exception
 218             return render_http_exception(
 219                 request, exc,
 220                 exc.get_description(environ))(environ, start_response)
 221
 222         controller = endpoint_to_controller(found_rule)
 223         # Make a reference to the controller's symbolic name on the request...
 224         # used for lazy context modification
 225         request.controller_name = found_rule.endpoint
 226
 227         # pass the request through our meddleware classes
 228         try:
 229             for m in self.meddleware:
 230                 response = m.process_request(request, controller)
 231                 if response is not None:
 232                     return response(environ, start_response)
 233         except HTTPException as e:
 234             return render_http_exception(
 235                 request, e,
 236                 e.get_description(environ))(environ, start_response)
 237
 238         request = hook_transform("modify_request", request)
 239
 240         request.start_response = start_response
 241
 242         # get the Http response from the controller
 243         try:
 244             response = controller(request)
 245         except HTTPException as e:
 246             response = render_http_exception(
 247                 request, e, e.get_description(environ))
 248
 249         # pass the response through the meddlewares
 250         try:
 251             for m in self.meddleware[::-1]:
 252                 m.process_response(request, response)
 253         except HTTPException as e:
 254             response = render_http_exception(
 255                 request, e, e.get_description(environ))
 256
 257         session_manager.save_session_to_cookie(request.session,
 258                                                request, response)
 259
 260         return response(environ, start_response)
 261
 262     def __call__(self, environ, start_response):
 263         ## If more errors happen that look like unclean sessions:
 264         # self.db.check_session_clean()
 265
 266         try:
 267             return self.call_backend(environ, start_response)
 268         finally:
 269             # Reset the sql session, so that the next request
 270             # gets a fresh session
 271             self.db.reset_after_request()
 272
 273
 274 def paste_app_factory(global_config, **app_config):
 275     configs = app_config['config'].split()
 276     mediagoblin_config = None
 277     for config in configs:
 278         if os.path.exists(config) and os.access(config, os.R_OK):
 279             mediagoblin_config = config
 280             break
 281
 282     if not mediagoblin_config:
 283         raise IOError("Usable mediagoblin config not found.")
 284
 285     mgoblin_app = MediaGoblinApp(mediagoblin_config)
 286     mgoblin_app = hook_transform('wrap_wsgi', mgoblin_app)
 287
 288     return mgoblin_app