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         check_db_up_to_date()
  97
  98         # Register themes
  99         self.theme_registry, self.current_theme = register_themes(app_config)
 100
 101         # Get the template environment
 102         self.template_loader = get_jinja_loader(
 103             app_config.get('local_templates'),
 104             self.current_theme,
 105             PluginManager().get_template_paths()
 106             )
 107
 108         # Check if authentication plugin is enabled and respond accordingly.
 109         self.auth = check_auth_enabled()
 110         if not self.auth:
 111             app_config['allow_comments'] = False
 112
 113         # Set up storage systems
 114         self.public_store, self.queue_store = setup_storage()
 115
 116         # set up routing
 117         self.url_map = get_url_map()
 118
 119         # set up staticdirector tool
 120         self.staticdirector = get_staticdirector(app_config)
 121
 122         # Setup celery, if appropriate
 123         if setup_celery and not app_config.get('celery_setup_elsewhere'):
 124             if os.environ.get('CELERY_ALWAYS_EAGER', 'false').lower() == 'true':
 125                 setup_celery_from_config(
 126                     app_config, global_config,
 127                     force_celery_always_eager=True)
 128             else:
 129                 setup_celery_from_config(app_config, global_config)
 130
 131         #######################################################
 132         # Insert appropriate things into mediagoblin.mg_globals
 133         #
 134         # certain properties need to be accessed globally eg from
 135         # validators, etc, which might not access to the request
 136         # object.
 137         #######################################################
 138
 139         setup_globals(app=self)
 140
 141         # Workbench *currently* only used by celery, so this only
 142         # matters in always eager mode :)
 143         setup_workbench()
 144
 145         # instantiate application meddleware
 146         self.meddleware = [common.import_component(m)(self)
 147                            for m in meddleware.ENABLED_MEDDLEWARE]
 148
 149     def call_backend(self, environ, start_response):
 150         request = Request(environ)
 151
 152         # Compatibility with django, use request.args preferrably
 153         request.GET = request.args
 154
 155         ## Routing / controller loading stuff
 156         map_adapter = self.url_map.bind_to_environ(request.environ)
 157
 158         # By using fcgi, mediagoblin can run under a base path
 159         # like /mediagoblin/. request.path_info contains the
 160         # path inside mediagoblin. If the something needs the
 161         # full path of the current page, that should include
 162         # the basepath.
 163         # Note: urlgen and routes are fine!
 164         request.full_path = environ["SCRIPT_NAME"] + request.path
 165         # python-routes uses SCRIPT_NAME. So let's use that too.
 166         # The other option would be:
 167         # request.full_path = environ["SCRIPT_URL"]
 168
 169         # Fix up environ for urlgen
 170         # See bug: https://bitbucket.org/bbangert/routes/issue/55/cache_hostinfo-breaks-on-https-off
 171         if environ.get('HTTPS', '').lower() == 'off':
 172             environ.pop('HTTPS')
 173
 174         ## Attach utilities to the request object
 175         # Do we really want to load this via middleware?  Maybe?
 176         session_manager = self.session_manager
 177         request.session = session_manager.load_session_from_cookie(request)
 178         # Attach self as request.app
 179         # Also attach a few utilities from request.app for convenience?
 180         request.app = self
 181
 182         request.db = self.db
 183         request.staticdirect = self.staticdirector
 184
 185         request.locale = translate.get_locale_from_request(request)
 186         request.template_env = template.get_jinja_env(
 187             self.template_loader, request.locale)
 188
 189         def build_proxy(endpoint, **kw):
 190             try:
 191                 qualified = kw.pop('qualified')
 192             except KeyError:
 193                 qualified = False
 194
 195             return map_adapter.build(
 196                     endpoint,
 197                     values=dict(**kw),
 198                     force_external=qualified)
 199
 200         request.urlgen = build_proxy
 201
 202         # Log user out if authentication_disabled
 203         no_auth_logout(request)
 204
 205         mg_request.setup_user_in_request(request)
 206
 207         request.controller_name = None
 208         try:
 209             found_rule, url_values = map_adapter.match(return_rule=True)
 210             request.matchdict = url_values
 211         except RequestRedirect as response:
 212             # Deal with 301 responses eg due to missing final slash
 213             return response(environ, start_response)
 214         except HTTPException as exc:
 215             # Stop and render exception
 216             return render_http_exception(
 217                 request, exc,
 218                 exc.get_description(environ))(environ, start_response)
 219
 220         controller = endpoint_to_controller(found_rule)
 221         # Make a reference to the controller's symbolic name on the request...
 222         # used for lazy context modification
 223         request.controller_name = found_rule.endpoint
 224
 225         # pass the request through our meddleware classes
 226         try:
 227             for m in self.meddleware:
 228                 response = m.process_request(request, controller)
 229                 if response is not None:
 230                     return response(environ, start_response)
 231         except HTTPException as e:
 232             return render_http_exception(
 233                 request, e,
 234                 e.get_description(environ))(environ, start_response)
 235
 236         request.start_response = start_response
 237
 238         # get the Http response from the controller
 239         try:
 240             response = controller(request)
 241         except HTTPException as e:
 242             response = render_http_exception(
 243                 request, e, e.get_description(environ))
 244
 245         # pass the response through the meddlewares
 246         try:
 247             for m in self.meddleware[::-1]:
 248                 m.process_response(request, response)
 249         except HTTPException as e:
 250             response = render_http_exception(
 251                 request, e, e.get_description(environ))
 252
 253         session_manager.save_session_to_cookie(request.session,
 254                                                request, response)
 255
 256         return response(environ, start_response)
 257
 258     def __call__(self, environ, start_response):
 259         ## If more errors happen that look like unclean sessions:
 260         # self.db.check_session_clean()
 261
 262         try:
 263             return self.call_backend(environ, start_response)
 264         finally:
 265             # Reset the sql session, so that the next request
 266             # gets a fresh session
 267             self.db.reset_after_request()
 268
 269
 270 def paste_app_factory(global_config, **app_config):
 271     configs = app_config['config'].split()
 272     mediagoblin_config = None
 273     for config in configs:
 274         if os.path.exists(config) and os.access(config, os.R_OK):
 275             mediagoblin_config = config
 276             break
 277
 278     if not mediagoblin_config:
 279         raise IOError("Usable mediagoblin config not found.")
 280
 281     mgoblin_app = MediaGoblinApp(mediagoblin_config)
 282     mgoblin_app = hook_transform('wrap_wsgi', mgoblin_app)
 283
 284     return mgoblin_app