Source code for fobi.wizard.views.dynamic

import logging
import re
from collections import OrderedDict

import six
from django import forms
from django.forms import ValidationError, formsets
from django.shortcuts import redirect
from django.urls import reverse
from django.utils.decorators import classonlymethod
from django.utils.translation import gettext as _
from django.views.generic import TemplateView
from formtools.wizard.forms import ManagementForm
from formtools.wizard.storage import get_storage
from formtools.wizard.storage.exceptions import NoFileStorageConfigured

logger = logging.getLogger(__name__)

__all__ = (
    "DynamicWizardView",
    "DynamicSessionWizardView",
    "DynamicCookieWizardView",
    "DynamicNamedUrlWizardView",
    "DynamicNamedUrlSessionWizardView",
    "DynamicNamedUrlCookieWizardView",
)


def normalize_name(name):
    """Convert camel-case style names into underscore separated words.

    Example::

        >>> normalize_name('oneTwoThree')
        'one_two_three'
        >>> normalize_name('FourFiveSix')
        'four_five_six'

    """
    new = re.sub("(((?<=[a-z])[A-Z])|([A-Z](?![A-Z]|$)))", "_\\1", name)
    return new.lower().strip("_")


class StepsHelper(object):
    """Site helper."""

    def __init__(self, wizard):
        self._wizard = wizard

    def __dir__(self):
        return self.all

    def __len__(self):
        return self.count

    def __repr__(self):
        return "<StepsHelper for %s (steps: %s)>" % (self._wizard, self.all)

    @property
    def all(self):
        """Returns the names of all steps/forms."""
        return list(self._wizard.get_form_list())

    @property
    def count(self):
        """Returns the total number of steps/forms in this the wizard."""
        return len(self.all)

    @property
    def current(self):
        """Return the current step.

        If no current step is stored in the storage backend, the first step
        will be returned.
        """
        return self._wizard.storage.current_step or self.first

    @property
    def first(self):
        """Return the name of the first step."""
        return self.all[0]

    @property
    def last(self):
        """Return the name of the last step."""
        return self.all[-1]

    @property
    def next(self):
        """Return the next step."""
        return self._wizard.get_next_step()

    @property
    def prev(self):
        """Return the previous step."""
        return self._wizard.get_prev_step()

    @property
    def index(self):
        """Return the index for the current step (0 based)."""
        return self._wizard.get_step_index()

    @property
    def index1(self):
        """Return the index for the current step (1 based)."""
        return self.index + 1

    @property
    def step0(self):
        """Step 0."""
        return int(self.index)

    @property
    def step1(self):
        """Step 1."""
        return int(self.index) + 1

    @property
    def is_last_step(self):
        """Check if last step."""
        return self.index1 == self.count


# class DynamicTemplateView(TemplateView):
#     """Dynamic template view."""
#
#     def __init__(self, *args, **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.
#         super(DynamicTemplateView, self).__init__(**kwargs)


[docs]class DynamicWizardView(TemplateView): """The WizardView is used to create multi-page forms. Handles all the storage and validation stuff. The wizard is based on Django's generic class based views. """ storage_name = None initial_dict = None instance_dict = None condition_dict = None template_name = "formtools/wizard/wizard_form.html" def __repr__(self): return "<%s: forms: %s>" % (self.__class__.__name__, self.form_list)
[docs] @classonlymethod def as_view(cls, *args, **kwargs): """As view. This method is used within urls.py to create unique wizardview instances for every request. We need to override this method because we add some kwargs which are needed to make the wizardview usable. """ initkwargs = cls.get_initkwargs(*args, **kwargs) return super(DynamicWizardView, cls).as_view(**initkwargs)
[docs] @classmethod def get_initkwargs( cls, form_list=None, initial_dict=None, instance_dict=None, condition_dict=None, *args, **kwargs, ): """Create a dict with all needed parameters. For the form wizard instances. * `form_list` - is a list of forms. The list entries can be single form classes or tuples of (`step_name`, `form_class`). If you pass a list of forms, the wizardview will convert the class list to (`zero_based_counter`, `form_class`). This is needed to access the form for a specific step. * `initial_dict` - contains a dictionary of initial data dictionaries. The key should be equal to the `step_name` in the `form_list` (or the str of the zero based counter - if no step_names added in the `form_list`) * `instance_dict` - contains a dictionary whose values are model instances if the step is based on a ``ModelForm`` and querysets if the step is based on a ``ModelFormSet``. The key should be equal to the `step_name` in the `form_list`. Same rules as for `initial_dict` apply. * `condition_dict` - contains a dictionary of boolean values or callables. If the value of for a specific `step_name` is callable it will be called with the wizardview instance as the only argument. If the return value is true, the step's form will be used. """ kwargs.update( { "initial_dict": initial_dict or kwargs.pop( "initial_dict", getattr(cls, "initial_dict", None) ) or {}, "instance_dict": instance_dict or kwargs.pop( "instance_dict", getattr(cls, "instance_dict", None) ) or {}, "condition_dict": condition_dict or kwargs.pop( "condition_dict", getattr(cls, "condition_dict", None) ) or {}, } ) return kwargs
[docs] def get_prefix(self, request, *args, **kwargs): """Get prefix.""" # TODO: Add some kind of unique id to prefix return normalize_name(self.__class__.__name__)
[docs] def compute_form_list(self, form_list=None, *args, **kwargs): """Compute the forms list.""" form_list = ( form_list or kwargs.pop("form_list", getattr(self, "form_list", None)) or [] ) computed_form_list = OrderedDict() # walk through the passed form list for i, form in enumerate(form_list): if isinstance(form, (list, tuple)): # if the element is a tuple, add the tuple to the new created # sorted dictionary. computed_form_list[six.text_type(form[0])] = form[1] else: # if not, add the form with a zero based counter as unicode computed_form_list[six.text_type(i)] = form # walk through the new created list of forms for form in six.itervalues(computed_form_list): if issubclass(form, formsets.BaseFormSet): # if the element is based on BaseFormSet (FormSet/ModelFormSet) # we need to override the form variable. form = form.form # check if any form contains a FileField, if yes, we need a # file_storage added to the wizardview (by subclassing). for field in six.itervalues(form.base_fields): if isinstance(field, forms.FileField) and not hasattr( self, "file_storage" ): raise NoFileStorageConfigured( "You need to define 'file_storage' in your " "wizard view in order to handle file uploads." ) return computed_form_list
[docs] def get_form_list(self): """Get form list. This method returns a form_list based on the initial form list but checks if there is a condition method/value in the condition_list. If an entry exists in the condition list, it will call/read the value and respect the result. (True means add the form, False means ignore the form) The form_list is always generated on the fly because condition methods could use data from other (maybe previous forms). """ form_list = OrderedDict() for form_key, form_class in six.iteritems( self.compute_form_list(self.form_list) ): # try to fetch the value from condition list, by default, the form # gets passed to the new list. condition = self.condition_dict.get(form_key, True) if callable(condition): # call the value if needed, passes the current instance. condition = condition(self) if condition: form_list[form_key] = form_class return form_list
[docs] def get_initial_wizard_data(self, *args, **kwargs): """This should be implemented in your subclass. You are supposed to return a dict with the dynamic properties, such as `form_list` or `template_name`. """ raise NotImplementedError( "You should implement `get_initial_wizard_data` method in your " "subclass." )
[docs] def dispatch(self, request, *args, **kwargs): """Dispatch. This method gets called by the routing engine. The first argument is `request` which contains a `HttpRequest` instance. The request is stored in `self.request` for later use. The storage instance is stored in `self.storage`. After processing the request using the `dispatch` method, the response gets updated by the storage engine (for example add cookies). """ # add the storage engine to the current wizardview instance self.prefix = self.get_prefix(request, *args, **kwargs) self.storage = get_storage( self.storage_name, self.prefix, request, getattr(self, "file_storage", None), ) self._form_list = [] initial_wizard_data = self.get_initial_wizard_data( request, *args, **kwargs ) for key, value in initial_wizard_data.items(): setattr(self, key, value) self.steps = StepsHelper(self) response = super(DynamicWizardView, self).dispatch( request, *args, **kwargs ) # update the response (e.g. adding cookies) self.storage.update_response(response) return response
[docs] def get(self, request, *args, **kwargs): """GET requests. This method handles GET requests. If a GET request reaches this point, the wizard assumes that the user just starts at the first step or wants to restart the process. The data of the wizard will be resetted before rendering the first step """ # TODO: Don't know if I should leave it like this. Perhaps, just # never reset on this step. if self.storage.current_step == self.steps.first: self.storage.reset() # reset the current step to the first step. self.storage.current_step = self.steps.first return self.render(self.get_form())
# def post(self, request, *args, **kwargs):
[docs] def post(self, *args, **kwargs): """POST requests. This method handles POST requests. The wizard will render either the current step (if form validation wasn't successful), the next step (if the current step was stored successful) or the done view (if no more steps are available) """ # Look for a wizard_goto_step element in the posted data which # contains a valid step name. If one was found, render the requested # form. (This makes stepping back a lot easier). wizard_goto_step = self.request.POST.get("wizard_goto_step", None) if wizard_goto_step and wizard_goto_step in self.get_form_list(): return self.render_goto_step(wizard_goto_step) # Check if form was refreshed management_form = ManagementForm(self.request.POST, prefix=self.prefix) if not management_form.is_valid(): raise ValidationError( _("ManagementForm data is missing or has been tampered."), code="missing_management_form", ) form_current_step = management_form.cleaned_data["current_step"] if ( form_current_step != self.steps.current and self.storage.current_step is not None ): # form refreshed, change current step self.storage.current_step = form_current_step # get the form for the current step form = self.get_form(data=self.request.POST, files=self.request.FILES) # and try to validate if form.is_valid(): # if the form is valid, store the cleaned data and files. self.storage.set_step_data( self.steps.current, self.process_step(form) ) self.storage.set_step_files( self.steps.current, self.process_step_files(form) ) # check if the current step is the last step if self.steps.current == self.steps.last: # no more steps, render done view return self.render_done(form, **kwargs) else: # proceed to the next step return self.render_next_step(form) return self.render(form)
[docs] def render_next_step(self, form, **kwargs): """Render next step. This method gets called when the next step/form should be rendered. `form` contains the last/current form. """ # get the form instance based on the data from the storage backend # (if available). next_step = self.steps.next new_form = self.get_form( next_step, data=self.storage.get_step_data(next_step), files=self.storage.get_step_files(next_step), ) # change the stored current step self.storage.current_step = next_step return self.render(new_form, **kwargs)
[docs] def render_goto_step(self, goto_step, **kwargs): """Render goto step. This method gets called when the current step has to be changed. `goto_step` contains the requested step to go to. """ self.storage.current_step = goto_step form = self.get_form( data=self.storage.get_step_data(self.steps.current), files=self.storage.get_step_files(self.steps.current), ) return self.render(form)
[docs] def render_done(self, form, **kwargs): """Render done. This method gets called when all forms passed. The method should also re-validate all steps to prevent manipulation. If any form fails to validate, `render_revalidation_failure` should get called. If everything is fine call `done`. """ final_forms = OrderedDict() # walk through the form list and try to validate the data again. for form_key in self.get_form_list(): form_obj = self.get_form( step=form_key, data=self.storage.get_step_data(form_key), files=self.storage.get_step_files(form_key), ) if not form_obj.is_valid(): return self.render_revalidation_failure( form_key, form_obj, **kwargs ) final_forms[form_key] = form_obj # render the done view and reset the wizard before returning the # response. This is needed to prevent from rendering done with the # same data twice. done_response = self.done( final_forms.values(), form_dict=final_forms, **kwargs ) self.storage.reset() return done_response
[docs] def get_form_prefix(self, step=None, form=None): """Get form prefix. Returns the prefix which will be used when calling the actual form for the given step. `step` contains the step-name, `form` the form which will be called with the returned prefix. If no step is given, the form_prefix will determine the current step automatically. """ if step is None: step = self.steps.current return str(step)
[docs] def get_form_initial(self, step): """Get form initial Returns a dictionary which will be passed to the form for `step` as `initial`. If no initial data was provided while initializing the form wizard, an empty dictionary will be returned. """ return self.initial_dict.get(step, {})
[docs] def get_form_instance(self, step): """Get form instance. Returns an object which will be passed to the form for `step` as `instance`. If no instance object was provided while initializing the form wizard, None will be returned. """ return self.instance_dict.get(step, None)
[docs] def get_form_kwargs(self, step=None): """Get form kwargs. Returns the keyword arguments for instantiating the form (or formset) on the given step. """ return {}
[docs] def get_form(self, step=None, data=None, files=None): """Get the form. Constructs the form for a given `step`. If no `step` is defined, the current step will be determined automatically. The form will be initialized using the `data` argument to prefill the new form. If needed, instance or queryset (for `ModelForm` or `ModelFormSet`) will be added too. """ if step is None: step = self.steps.current form_class = self.compute_form_list(self.form_list)[step] # prepare the kwargs for the form instance. kwargs = self.get_form_kwargs(step) kwargs.update( { "data": data, "files": files, "prefix": self.get_form_prefix(step, form_class), "initial": self.get_form_initial(step), } ) if issubclass( form_class, (forms.ModelForm, forms.models.BaseInlineFormSet) ): # If the form is based on ModelForm or InlineFormSet, # add instance if available and not previously set. kwargs.setdefault("instance", self.get_form_instance(step)) elif issubclass(form_class, forms.models.BaseModelFormSet): # If the form is based on ModelFormSet, add queryset if available # and not previous set. kwargs.setdefault("queryset", self.get_form_instance(step)) return form_class(**kwargs)
[docs] def process_step(self, form): """Process the step. This method is used to post-process the form data. By default, it returns the raw `form.data` dictionary. """ return self.get_form_step_data(form)
[docs] def process_step_files(self, form): """Process step files. This method is used to post-process the form files. By default, it returns the raw `form.files` dictionary. """ return self.get_form_step_files(form)
[docs] def render_revalidation_failure(self, step, form, **kwargs): """Render revalidation failure. Gets called when a form doesn't validate when rendering the done view. By default, it changes the current step to failing forms step and renders the form. """ self.storage.current_step = step return self.render(form, **kwargs)
[docs] def get_form_step_data(self, form): """Get form step data. Is used to return the raw form data. You may use this method to manipulate the data. """ return form.data
[docs] def get_form_step_files(self, form): """Get form step files. Is used to return the raw form files. You may use this method to manipulate the data. """ return form.files
[docs] def get_all_cleaned_data(self): """Get all cleaned data. Returns a merged dictionary of all step cleaned_data dictionaries. If a step contains a `FormSet`, the key will be prefixed with 'formset-' and contain a list of the formset cleaned_data dictionaries. """ cleaned_data = {} for form_key in self.get_form_list(): form_obj = self.get_form( step=form_key, data=self.storage.get_step_data(form_key), files=self.storage.get_step_files(form_key), ) if form_obj.is_valid(): if isinstance(form_obj.cleaned_data, (tuple, list)): cleaned_data.update( {"formset-%s" % form_key: form_obj.cleaned_data} ) else: cleaned_data.update(form_obj.cleaned_data) return cleaned_data
[docs] def get_cleaned_data_for_step(self, step): """Get clean data for step. Returns the cleaned data for a given `step`. Before returning the cleaned data, the stored values are revalidated through the form. If the data doesn't validate, None will be returned. """ if step in self.form_list: form_obj = self.get_form( step=step, data=self.storage.get_step_data(step), files=self.storage.get_step_files(step), ) if form_obj.is_valid(): return form_obj.cleaned_data return None
[docs] def get_next_step(self, step=None): """Get next step. Returns the next step after the given `step`. If no more steps are available, None will be returned. If the `step` argument is None, the current step will be determined automatically. """ if step is None: step = self.steps.current form_list = self.get_form_list() keys = list(form_list.keys()) key = keys.index(step) + 1 if len(keys) > key: return keys[key] return None
[docs] def get_prev_step(self, step=None): """Get previous step. Returns the previous step before the given `step`. If there are no steps available, None will be returned. If the `step` argument is None, the current step will be determined automatically. """ if step is None: step = self.steps.current form_list = self.get_form_list() keys = list(form_list.keys()) key = keys.index(step) - 1 if key >= 0: return keys[key] return None
[docs] def get_step_index(self, step=None): """Get step index. Returns the index for the given `step` name. If no step is given, the current step will be used to get the index. """ if step is None: step = self.steps.current return list(self.get_form_list().keys()).index(step)
[docs] def get_context_data(self, form, **kwargs): """Get context data. Returns the template context for a step. You can overwrite this method to add more data for all or some steps. This method returns a dictionary containing the rendered form step. Available template context variables are: * all extra data stored in the storage backend * `wizard` - a dictionary representation of the wizard instance Example:: class MyWizard(WizardView): def get_context_data(self, form, **kwargs): context = super(MyWizard, self).get_context_data(form=form, **kwargs) if self.steps.current == 'my_step_name': context.update({'another_var': True}) return context """ context = super(DynamicWizardView, self).get_context_data( form=form, **kwargs ) context.update(self.storage.extra_data) context["wizard"] = { "form": form, "steps": self.steps, "management_form": ManagementForm( prefix=self.prefix, initial={ "current_step": self.steps.current, }, ), } return context
[docs] def render(self, form=None, **kwargs): """Render. Returns a ``HttpResponse`` containing all needed context data. """ form = form or self.get_form() context = self.get_context_data(form=form, **kwargs) return self.render_to_response(context)
[docs] def done(self, form_list, **kwargs): """Done. This method must be overridden by a subclass to process to form data after processing all steps. """ raise NotImplementedError( "Your %s class has not defined a done() " "method, which is required." % self.__class__.__name__ )
[docs]class DynamicSessionWizardView(DynamicWizardView): """A WizardView with pre-configured SessionStorage backend.""" storage_name = "formtools.wizard.storage.session.SessionStorage"
[docs]class DynamicCookieWizardView(DynamicWizardView): """A WizardView with pre-configured CookieStorage backend.""" storage_name = "formtools.wizard.storage.cookie.CookieStorage"
[docs]class DynamicNamedUrlWizardView(DynamicWizardView): """A WizardView with URL named steps support.""" url_name = None done_step_name = None
[docs] @classmethod def get_initkwargs(cls, *args, **kwargs): """Get init kwargs. We require a url_name to reverse URLs later. Additionally users can pass a done_step_name to change the URL name of the "done" view. """ assert ( "url_name" in kwargs ), "URL name is needed to resolve correct wizard URLs" extra_kwargs = { "done_step_name": kwargs.pop("done_step_name", "done"), "url_name": kwargs.pop("url_name"), } initkwargs = super(DynamicNamedUrlWizardView, cls).get_initkwargs( *args, **kwargs ) initkwargs.update(extra_kwargs) assert initkwargs["done_step_name"] not in initkwargs["form_list"], ( 'step name "%s" is reserved for "done" view' % initkwargs["done_step_name"] ) return initkwargs
[docs] def get_step_url(self, step): """Get step URL.""" return reverse(self.url_name, kwargs={"step": step})
[docs] def get(self, *args, **kwargs): """GET request. This renders the form or, if needed, does the http redirects. """ step_url = kwargs.get("step", None) if step_url is None: if "reset" in self.request.GET: self.storage.reset() self.storage.current_step = self.steps.first if self.request.GET: query_string = "?%s" % self.request.GET.urlencode() else: query_string = "" return redirect( self.get_step_url(self.steps.current) + query_string ) # is the current step the "done" name/view? elif step_url == self.done_step_name: last_step = self.steps.last return self.render_done( self.get_form( step=last_step, data=self.storage.get_step_data(last_step), files=self.storage.get_step_files(last_step), ), **kwargs, ) # is the url step name not equal to the step in the storage? # if yes, change the step in the storage (if name exists) elif step_url == self.steps.current: # URL step name and storage step name are equal, render! return self.render( self.get_form( data=self.storage.current_step_data, files=self.storage.current_step_files, ), **kwargs, ) elif step_url in self.get_form_list(): self.storage.current_step = step_url return self.render( self.get_form( data=self.storage.current_step_data, files=self.storage.current_step_files, ), **kwargs, ) # invalid step name, reset to first and redirect. else: self.storage.current_step = self.steps.first return redirect(self.get_step_url(self.steps.first))
[docs] def post(self, *args, **kwargs): """POST request. Do a redirect if user presses the prev. step button. The rest of this is super'd from WizardView. """ wizard_goto_step = self.request.POST.get("wizard_goto_step", None) if wizard_goto_step and wizard_goto_step in self.get_form_list(): return self.render_goto_step(wizard_goto_step) return super(DynamicNamedUrlWizardView, self).post(*args, **kwargs)
[docs] def get_context_data(self, form, **kwargs): """Get context data. NamedUrlWizardView provides the url_name of this wizard in the context dict `wizard`. """ context = super(DynamicNamedUrlWizardView, self).get_context_data( form=form, **kwargs ) context["wizard"]["url_name"] = self.url_name return context
[docs] def render_next_step(self, form, **kwargs): """Render next step. When using the NamedUrlWizardView, we have to redirect to update the browser's URL to match the shown step. """ next_step = self.get_next_step() self.storage.current_step = next_step return redirect(self.get_step_url(next_step))
[docs] def render_goto_step(self, goto_step, **kwargs): """Render goto step. This method gets called when the current step has to be changed. `goto_step` contains the requested step to go to. """ self.storage.current_step = goto_step return redirect(self.get_step_url(goto_step))
[docs] def render_revalidation_failure(self, failed_step, form, **kwargs): """Render revalidation failure. When a step fails, we have to redirect the user to the first failing step. """ self.storage.current_step = failed_step return redirect(self.get_step_url(failed_step))
[docs] def render_done(self, form, **kwargs): """Render done. When rendering the done view, we have to redirect first (if the URL name doesn't fit). """ if kwargs.get("step", None) != self.done_step_name: return redirect(self.get_step_url(self.done_step_name)) return super(DynamicNamedUrlWizardView, self).render_done( form, **kwargs )
[docs]class DynamicNamedUrlSessionWizardView(DynamicNamedUrlWizardView): """A NamedUrlWizardView with pre-configured SessionStorage backend.""" storage_name = "formtools.wizard.storage.session.SessionStorage"
[docs]class DynamicNamedUrlCookieWizardView(DynamicNamedUrlWizardView): """A NamedUrlFormWizard with pre-configured CookieStorageBackend.""" storage_name = "formtools.wizard.storage.cookie.CookieStorage"