FormView | Django Class-Based Views Django 3.2 (2024)

def _allowed_methods(self): return [m.upper() for m in self.http_method_names if hasattr(self, m)]

@classonlymethoddef as_view(cls, **initkwargs): """Main entry point for a request-response process.""" for key in initkwargs: if key in cls.http_method_names: raise TypeError( 'The method name %s is not accepted as a keyword argument ' 'to %s().' % (key, cls.__name__) ) if not hasattr(cls, key): raise TypeError("%s() received an invalid keyword %r. as_view " "only accepts arguments that are already " "attributes of the class." % (cls.__name__, key)) def view(request, *args, **kwargs): self = cls(**initkwargs) self.setup(request, *args, **kwargs) if not hasattr(self, 'request'): raise AttributeError( "%s instance has no 'request' attribute. Did you override " "setup() and forget to call super()?" % cls.__name__ ) return self.dispatch(request, *args, **kwargs) view.view_class = cls view.view_initkwargs = initkwargs # take name and docstring from class update_wrapper(view, cls, updated=()) # and possible attributes set by decorators # like csrf_exempt from dispatch update_wrapper(view, cls.dispatch, assigned=()) return view

def dispatch(self, request, *args, **kwargs): # Try to dispatch to the right method; if a method doesn't exist, # defer to the error handler. Also defer to the error handler if the # request method isn't on the approved list. if request.method.lower() in self.http_method_names: handler = getattr(self, request.method.lower(), self.http_method_not_allowed) else: handler = self.http_method_not_allowed return handler(request, *args, **kwargs)

def form_invalid(self, form): """If the form is invalid, render the invalid form.""" return self.render_to_response(self.get_context_data(form=form))

def form_valid(self, form): """If the form is valid, redirect to the supplied URL.""" return HttpResponseRedirect(self.get_success_url())

def get(self, request, *args, **kwargs): """Handle GET requests: instantiate a blank version of the form.""" return self.render_to_response(self.get_context_data())

Insert the form into the context dict.

def get_context_data(self, **kwargs): """Insert the form into the context dict.""" if 'form' not in kwargs: kwargs['form'] = self.get_form() return super().get_context_data(**kwargs)

def get_form(self, form_class=None): """Return an instance of the form to be used in this view.""" if form_class is None: form_class = self.get_form_class() return form_class(**self.get_form_kwargs())

def get_form_class(self): """Return the form class to use.""" return self.form_class

def get_form_kwargs(self): """Return the keyword arguments for instantiating the form.""" kwargs = { 'initial': self.get_initial(), 'prefix': self.get_prefix(), } if self.request.method in ('POST', 'PUT'): kwargs.update({ 'data': self.request.POST, 'files': self.request.FILES, }) return kwargs

def get_initial(self): """Return the initial data to use for forms on this view.""" return self.initial.copy()

def get_prefix(self): """Return the prefix to use for forms.""" return self.prefix

def get_success_url(self): """Return the URL to redirect to after processing a valid form.""" if not self.success_url: raise ImproperlyConfigured("No URL to redirect to. Provide a success_url.") return str(self.success_url) # success_url may be lazy

def get_template_names(self): """ Return a list of template names to be used for the request. Must return a list. May not be called if render_to_response() is overridden. """ if self.template_name is None: raise ImproperlyConfigured( "TemplateResponseMixin requires either a definition of " "'template_name' or an implementation of 'get_template_names()'") else: return [self.template_name]

def http_method_not_allowed(self, request, *args, **kwargs): logger.warning( 'Method Not Allowed (%s): %s', request.method, request.path, extra={'status_code': 405, 'request': request} ) return HttpResponseNotAllowed(self._allowed_methods())

def __init__(self, **kwargs): """ Constructor. Called in the URLconf; can contain helpful extra keyword arguments, and other things. """ # Go through keyword arguments, and either save their values to our # instance, or raise an error. for key, value in kwargs.items(): setattr(self, key, value)

def options(self, request, *args, **kwargs): """Handle responding to requests for the OPTIONS HTTP verb.""" response = HttpResponse() response.headers['Allow'] = ', '.join(self._allowed_methods()) response.headers['Content-Length'] = '0' return response

def post(self, request, *args, **kwargs): """ Handle POST requests: instantiate a form instance with the passed POST variables and then check if it's valid. """ form = self.get_form() if form.is_valid(): return self.form_valid(form) else: return self.form_invalid(form)

def put(self, *args, **kwargs): return self.post(*args, **kwargs)

def render_to_response(self, context, **response_kwargs): """ Return a response, using the `response_class` for this view, with a template rendered with the given context. Pass response_kwargs to the constructor of the response class. """ response_kwargs.setdefault('content_type', self.content_type) return self.response_class( request=self.request, template=self.get_template_names(), context=context, using=self.template_engine, **response_kwargs )

def setup(self, request, *args, **kwargs): """Initialize attributes shared by all view methods.""" if hasattr(self, 'get') and not hasattr(self, 'head'): self.head = self.get self.request = request self.args = args self.kwargs = kwargs