| import sys |
| |
| from django import http |
| from django.core import signals |
| from django.utils.encoding import force_unicode |
| |
| class BaseHandler(object): |
| # Changes that are always applied to a response (in this order). |
| response_fixes = [ |
| http.fix_location_header, |
| http.conditional_content_removal, |
| http.fix_IE_for_attach, |
| http.fix_IE_for_vary, |
| ] |
| |
| def __init__(self): |
| self._request_middleware = self._view_middleware = self._response_middleware = self._exception_middleware = None |
| |
| def load_middleware(self): |
| """ |
| Populate middleware lists from settings.MIDDLEWARE_CLASSES. |
| |
| Must be called after the environment is fixed (see __call__). |
| """ |
| from django.conf import settings |
| from django.core import exceptions |
| self._request_middleware = [] |
| self._view_middleware = [] |
| self._response_middleware = [] |
| self._exception_middleware = [] |
| for middleware_path in settings.MIDDLEWARE_CLASSES: |
| try: |
| dot = middleware_path.rindex('.') |
| except ValueError: |
| raise exceptions.ImproperlyConfigured, '%s isn\'t a middleware module' % middleware_path |
| mw_module, mw_classname = middleware_path[:dot], middleware_path[dot+1:] |
| try: |
| mod = __import__(mw_module, {}, {}, ['']) |
| except ImportError, e: |
| raise exceptions.ImproperlyConfigured, 'Error importing middleware %s: "%s"' % (mw_module, e) |
| try: |
| mw_class = getattr(mod, mw_classname) |
| except AttributeError: |
| raise exceptions.ImproperlyConfigured, 'Middleware module "%s" does not define a "%s" class' % (mw_module, mw_classname) |
| |
| try: |
| mw_instance = mw_class() |
| except exceptions.MiddlewareNotUsed: |
| continue |
| |
| if hasattr(mw_instance, 'process_request'): |
| self._request_middleware.append(mw_instance.process_request) |
| if hasattr(mw_instance, 'process_view'): |
| self._view_middleware.append(mw_instance.process_view) |
| if hasattr(mw_instance, 'process_response'): |
| self._response_middleware.insert(0, mw_instance.process_response) |
| if hasattr(mw_instance, 'process_exception'): |
| self._exception_middleware.insert(0, mw_instance.process_exception) |
| |
| def get_response(self, request): |
| "Returns an HttpResponse object for the given HttpRequest" |
| from django.core import exceptions, urlresolvers |
| from django.conf import settings |
| |
| # Apply request middleware |
| for middleware_method in self._request_middleware: |
| response = middleware_method(request) |
| if response: |
| return response |
| |
| # Get urlconf from request object, if available. Otherwise use default. |
| urlconf = getattr(request, "urlconf", settings.ROOT_URLCONF) |
| |
| resolver = urlresolvers.RegexURLResolver(r'^/', urlconf) |
| try: |
| callback, callback_args, callback_kwargs = resolver.resolve( |
| request.path_info) |
| |
| # Apply view middleware |
| for middleware_method in self._view_middleware: |
| response = middleware_method(request, callback, callback_args, callback_kwargs) |
| if response: |
| return response |
| |
| try: |
| response = callback(request, *callback_args, **callback_kwargs) |
| except Exception, e: |
| # If the view raised an exception, run it through exception |
| # middleware, and if the exception middleware returns a |
| # response, use that. Otherwise, reraise the exception. |
| for middleware_method in self._exception_middleware: |
| response = middleware_method(request, e) |
| if response: |
| return response |
| raise |
| |
| # Complain if the view returned None (a common error). |
| if response is None: |
| try: |
| view_name = callback.func_name # If it's a function |
| except AttributeError: |
| view_name = callback.__class__.__name__ + '.__call__' # If it's a class |
| raise ValueError, "The view %s.%s didn't return an HttpResponse object." % (callback.__module__, view_name) |
| |
| return response |
| except http.Http404, e: |
| if settings.DEBUG: |
| from django.views import debug |
| return debug.technical_404_response(request, e) |
| else: |
| try: |
| callback, param_dict = resolver.resolve404() |
| return callback(request, **param_dict) |
| except: |
| try: |
| return self.handle_uncaught_exception(request, resolver, sys.exc_info()) |
| finally: |
| receivers = signals.got_request_exception.send(sender=self.__class__, request=request) |
| except exceptions.PermissionDenied: |
| return http.HttpResponseForbidden('<h1>Permission denied</h1>') |
| except SystemExit: |
| # Allow sys.exit() to actually exit. See tickets #1023 and #4701 |
| raise |
| except: # Handle everything else, including SuspiciousOperation, etc. |
| # Get the exception info now, in case another exception is thrown later. |
| exc_info = sys.exc_info() |
| receivers = signals.got_request_exception.send(sender=self.__class__, request=request) |
| return self.handle_uncaught_exception(request, resolver, exc_info) |
| |
| def handle_uncaught_exception(self, request, resolver, exc_info): |
| """ |
| Processing for any otherwise uncaught exceptions (those that will |
| generate HTTP 500 responses). Can be overridden by subclasses who want |
| customised 500 handling. |
| |
| Be *very* careful when overriding this because the error could be |
| caused by anything, so assuming something like the database is always |
| available would be an error. |
| """ |
| from django.conf import settings |
| from django.core.mail import mail_admins |
| |
| if settings.DEBUG_PROPAGATE_EXCEPTIONS: |
| raise |
| |
| if settings.DEBUG: |
| from django.views import debug |
| return debug.technical_500_response(request, *exc_info) |
| |
| # When DEBUG is False, send an error message to the admins. |
| subject = 'Error (%s IP): %s' % ((request.META.get('REMOTE_ADDR') in settings.INTERNAL_IPS and 'internal' or 'EXTERNAL'), request.path) |
| try: |
| request_repr = repr(request) |
| except: |
| request_repr = "Request repr() unavailable" |
| message = "%s\n\n%s" % (self._get_traceback(exc_info), request_repr) |
| mail_admins(subject, message, fail_silently=True) |
| # Return an HttpResponse that displays a friendly error message. |
| callback, param_dict = resolver.resolve500() |
| return callback(request, **param_dict) |
| |
| def _get_traceback(self, exc_info=None): |
| "Helper function to return the traceback as a string" |
| import traceback |
| return '\n'.join(traceback.format_exception(*(exc_info or sys.exc_info()))) |
| |
| def apply_response_fixes(self, request, response): |
| """ |
| Applies each of the functions in self.response_fixes to the request and |
| response, modifying the response in the process. Returns the new |
| response. |
| """ |
| for func in self.response_fixes: |
| response = func(request, response) |
| return response |
| |
| def get_script_name(environ): |
| """ |
| Returns the equivalent of the HTTP request's SCRIPT_NAME environment |
| variable. If Apache mod_rewrite has been used, returns what would have been |
| the script name prior to any rewriting (so it's the script name as seen |
| from the client's perspective), unless DJANGO_USE_POST_REWRITE is set (to |
| anything). |
| """ |
| from django.conf import settings |
| if settings.FORCE_SCRIPT_NAME is not None: |
| return force_unicode(settings.FORCE_SCRIPT_NAME) |
| |
| # If Apache's mod_rewrite had a whack at the URL, Apache set either |
| # SCRIPT_URL or REDIRECT_URL to the full resource URL before applying any |
| # rewrites. Unfortunately not every webserver (lighttpd!) passes this |
| # information through all the time, so FORCE_SCRIPT_NAME, above, is still |
| # needed. |
| script_url = environ.get('SCRIPT_URL', u'') |
| if not script_url: |
| script_url = environ.get('REDIRECT_URL', u'') |
| if script_url: |
| return force_unicode(script_url[:-len(environ.get('PATH_INFO', ''))]) |
| return force_unicode(environ.get('SCRIPT_NAME', u'')) |
| |
