Source code for keystone.server.flask.application

#    Licensed under the Apache License, Version 2.0 (the "License"); you may
#    not use this file except in compliance with the License. You may obtain
#    a copy of the License at
#    Unless required by applicable law or agreed to in writing, software
#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
#    License for the specific language governing permissions and limitations
#    under the License.

import functools
import sys

import flask
import oslo_i18n
from oslo_log import log
from oslo_middleware import healthcheck

    # werkzeug 0.15.x
    from werkzeug.middleware import dispatcher as wsgi_dispatcher
except ImportError:
    # werkzeug 0.14.x
    import werkzeug.wsgi as wsgi_dispatcher

import keystone.api
from keystone import exception
from keystone.oauth2 import handlers as oauth2_handlers
from keystone.receipt import handlers as receipt_handlers
from keystone.server.flask import common as ks_flask
from keystone.server.flask.request_processing import json_body
from keystone.server.flask.request_processing import req_logging

LOG = log.getLogger(__name__)

[docs]def fail_gracefully(f): """Log exceptions and aborts.""" @functools.wraps(f) def wrapper(*args, **kw): try: return f(*args, **kw) except Exception as e: LOG.debug(e, exc_info=True) # exception message is printed to all logs LOG.critical(e) sys.exit(1) return wrapper
def _add_vary_x_auth_token_header(response): # Add the expected Vary Header, this is run after every request in the # response-phase response.headers['Vary'] = 'X-Auth-Token' return response def _best_match_language(): """Determine the best available locale. This returns best available locale based on the Accept-Language HTTP header passed in the request. """ if not flask.request.accept_languages: return None return flask.request.accept_languages.best_match( oslo_i18n.get_available_languages('keystone')) def _handle_keystone_exception(error): # TODO(adriant): register this with its own specific handler: if isinstance(error, exception.InsufficientAuthMethods): return receipt_handlers.build_receipt(error) elif isinstance(error, exception.OAuth2Error): return oauth2_handlers.build_response(error) # Handle logging if isinstance(error, exception.Unauthorized): LOG.warning( "Authorization failed. %(exception)s from %(remote_addr)s", {'exception': error, 'remote_addr': flask.request.remote_addr}) else: LOG.exception(str(error)) # Render the exception to something user "friendly" error_message = error.args[0] message = oslo_i18n.translate(error_message, _best_match_language()) if message is error_message: # translate() didn't do anything because it wasn't a Message, # convert to a string. message = str(message) body = dict( error={ 'code': error.code, 'title': error.title, 'message': message} ) if isinstance(error, exception.AuthPluginException): body['error']['identity'] = error.authentication # Create the response and set status code. response = flask.jsonify(body) response.status_code = error.code # Add the appropriate WWW-Authenticate header for Unauthorized if isinstance(error, exception.Unauthorized): url = ks_flask.base_url() response.headers['WWW-Authenticate'] = 'Keystone uri="%s"' % url return response def _handle_unknown_keystone_exception(error): # translate a python exception to something we can properly render as # an API error. if isinstance(error, TypeError): new_exc = exception.ValidationError(error) else: new_exc = exception.UnexpectedError(error) return _handle_keystone_exception(new_exc)
[docs]@fail_gracefully def application_factory(name='public'): if name not in ('admin', 'public'): raise RuntimeError('Application name (for base_url lookup) must be ' 'either `admin` or `public`.') app = flask.Flask(name) # Register Error Handler Function for Keystone Errors. # NOTE(morgan): Flask passes errors to an error handling function. All of # keystone's api errors are explicitly registered in # keystone.exception.KEYSTONE_API_EXCEPTIONS and those are in turn # registered here to ensure a proper error is bubbled up to the end user # instead of a 500 error. for exc in exception.KEYSTONE_API_EXCEPTIONS: app.register_error_handler(exc, _handle_keystone_exception) # Register extra (python) exceptions with the proper exception handler, # specifically TypeError. It will render as a 400 error, but presented in # a "web-ified" manner app.register_error_handler(TypeError, _handle_unknown_keystone_exception) # Add core before request functions app.before_request(req_logging.log_request_info) app.before_request(json_body.json_body_before_request) # Add core after request functions app.after_request(_add_vary_x_auth_token_header) # NOTE(morgan): Configure the Flask Environment for our needs. app.config.update( # We want to bubble up Flask Exceptions (for now) PROPAGATE_EXCEPTIONS=True) for api in keystone.api.__apis__: for api_bp in api.APIs: api_bp.instantiate_and_register_to_app(app) # Load in Healthcheck and map it to /healthcheck hc_app = healthcheck.Healthcheck.app_factory( {}, oslo_config_project='keystone') # Use the simple form of the dispatch middleware, no extra logic needed # for legacy dispatching. This is to mount /healthcheck at a consistent # place app.wsgi_app = wsgi_dispatcher.DispatcherMiddleware( app.wsgi_app, {'/healthcheck': hc_app}) return app