I am trying to handle Django form in a more gentle way and actually, I have no idea how to push further this topic. I have a View which is responsible for displaying a Form, in If form.is_valid() condition I am looking for free parking spots, if I found nothing then I would like to show an Error to the user or pass to context additional data. Fist part I've covered easily but I have no idea how to show an error or something similar.
class BookParkingSpot(FormMixin, generic.ListView):
template_name = 'parking/book_spot.html'
form_class = BookParkingSpotForm
model = ParkingBooking
def post(self, request, *args, **kwargs):
form = BookParkingSpotForm(self.request.POST)
if form.is_valid():
parking_spot_list = ParkingSpot.objects.all().exclude(
parkingbooking__booking_time_start__lte=form.instance.booking_time_end,
parkingbooking__booking_time_end__gte=form.instance.booking_time_start
)
if parking_spot_list.exists():
random_spot = random.choice(parking_spot_list)
reservation = ParkingBooking.objects.create(
car=form.instance.car,
booking_owner=self.request.user,
spot=random_spot,
booking_time_end=form.instance.booking_time_start,
booking_time_start=form.instance.booking_time_end,
)
return redirect(reservation.get_absolute_url())
else: # this part doesn't work
context = self.get_context_data(**kwargs)
return render(self.request, self.template_name, context)
Any idea how to improve it?
Best write your validations in the form methods. Read about in: https://docs.djangoproject.com/en/4.0/ref/forms/validation/#validating-fields-with-clean
from django.core.exceptions import ValidationError
class BookParkingSpotForm(forms.Form):
# ...
def clean(self):
cleaned_data = super().clean()
p_list = ParkingSpot.objects.all().exclude(
parkingbooking__booking_time_start__lte=cleaned_data.booking_time_end,
parkingbooking__booking_time_end__gte=cleaned_data.booking_time_start
)
if p_list.count() == 0:
raise ValidationError('Your error message')
And to access to the form data use form.cleaned_data['field_name'] and not form.instance.field_name.
Sorry everyone for the inconvenient but again after posting on StackOverflow I figured out how to resolve this issue and it was very simple, I am still learning Django ;)
So the answer to my question lies in the last part of my code, if I didn't find any free parking spots then I can render the same page with additional data like on below example and pass form object to context:
return render(self.request, 'parking/book_spot.html',
{'errors': "There are no free parking spots in selected time",
'form': form})
Related
I am trying to make a simple form, that conditionally shows the website input field based on the value of another database field (that is not on the form) status. For the sake of this process the status field is not editable by the user, just by the admin. Both fields are in the same table: profile.
After working at this for a while I copped-out and just did the conditional hiding and showing on the template. But, I realise this is the unsophisticated method, and would like to improve it.
What I tried so far in forms.py:
class WebsiteForm(forms.ModelForm):
class Meta:
model = Profile
fields = (
'e-mail',
'website',
)
if Profile.status == 'personal' :
exclude = ('website',)
This method in forms.py works effectively, in that I can conditionally show and hide the field if I use test comparitors in the if statement like:
if 1 == 1:
or
if 1 != 1:
But, I cannot get an effective test using the field Profile.status, the value in the field seems to be unavailable at the point the if test in forms.py is performed.
If I use print(Profile.status) I get the following output in the terminal: user__profile__status__isnull, so I think this means that I am at least testing the correct field in the database. Although I am also noting that this output only shows at initialisation of runserver, not when the form page is accessed.
One final point, the user is authenticated and editing their own record.
Any help very much appreciated.
After a lot of trial and even more error, and some wide-ranging searching, I found the answer via the documentation at https://ccbv.co.uk/.
Essentially the path I decided to take was to use a different form for the respective fields that I wanted to use (I'm sure there are other solutions out there that add or subtract fields from the views). This involved changing the form_class with get_form_class:
# views.py
class telephone_view(UpdateView):
template_name = 'account/telephone.html'
#no need to define "form_class" here
#form_class = TelephoneForm
success_url = '/accounts/telephone/'
def get_form_class(self):
if self.request.user.profile.status == 'managed':
messages.success(self.request, _('you got the managed form'))
return TelephoneFormExtended
else:
messages.success(self.request, _('you got the other form'))
return TelephoneFormLight
def get_object(self, queryset=None):
return Profile.get_or_create_for_user(self.request.user)
def form_valid(self, form):
messages.success(self.request, _('Your telephone setting was updated'))
return super(telephone_view, self).form_valid(form)
#method_decorator(login_required)
def dispatch(self, *args, **kwargs):
return super(telephone_view, self).dispatch(*args, **kwargs)
After working it out for myself I also found this answer which does the same thing:
Updateview with dynamic form_class
Good evening, I am trying to get the id of my model Note that is sent by means of a form, but when I put form.id it tells me that id is not defined, try to get it through the user session but it says that it was not found.
def add_book(request):
template_name = 'books/create_note.html'
book = get_or_create_book(request)
form = NoteForm(request.POST)
if request.method == 'POST' and form.is_valid():
note = Note.objects.get(pk=form.pk)
book.notes.add(note)
form.save()
return redirect('books:book')
return render(request, template_name, {
'form': form,
})
and this is the form
class NoteForm(ModelForm):
class Meta:
model = Note
fields = (
'title', 'nota'
)
labels = {
'title': 'Titulo',
'nota': 'Nota',
}
try creating an instance of my Note model but when it comes time to create it tells me it is empty.
I'm new to Django, but I had similar problems that frustrate me. not sure if I have the hang of it yet, but I think what might be happening is that when you first go to the page there is a GET request, so your if statement misses it. It then it reaches the last line and goes to template_name without the form being assigned so the form never gets a Post requests. In the terminal you can see the POST and GET requests. I ended up also printing out request.method a lot before and after if statements just to help trace what was going on.
else:
form=NoteForm()
Then your return render(request,....
making sure it goes back to the correct html page.
The thing that worked for me eventually was something like
def Search_Page(request):
if request.method=='POST':
form = Search_Page_Form(request.POST)
if form.is_valid():
do some stuff and save the change to the model
return(redirect('mainapp:Evaluate_Page'))
else:
form=Search_Page_Form()
return render(request, 'mainapp/Search_Page.html', {'form': form})
I've been working with Django for about 3 months now and feel I'm getting a bit better, working my way up to class based views. On the surface they seem cleaner and easier to understand and in some cases they are. In others, not so much. I am trying to use a simple drop down view via ModelChoiceField and a form. I can get it to work with a function based view as shown below in my views.py file:
def book_by_name(request):
form = BookByName(request.POST or None)
if request.method == 'POST':
if form.is_valid():
book_byname = form.cleaned_data['dropdown']
return HttpResponseRedirect(book_byname.get_absolute_url1())
return render(request,'library/book_list.html',{'form':form})
Here is my form in forms.py:
class BookByName(forms.Form):
dropdown = forms.ModelChoiceField(queryset=Book.objects.none())
def __init__(self, *args, **kwargs):
super(BookByName, self).__init__(*args, **kwargs)
self.fields['dropdown'].widget.attrs['class'] = 'choices1'
self.fields['dropdown'].empty_label = ''
self.fields['dropdown'].queryset = Book.objects.order_by('publisher')
This code works. When I have tried to convert to a Class Based View, that's when the trouble begins. I tried to do something like this in views.py:
class BookByNameView(FormView, View):
form_class = BookByName
initial = { 'Book' : Book }
template_name = 'library/book_list.html'
def get(self, request, *args, **kwargs):
form = self.form_class(initial=self.initial)
return render(request, self.template_name, {'form': form})
def get_success_url(self, *args):
return reverse_lazy('library:book_detail', args = (self.object.id,))
When using this with the same form, I receive an attribute error,
'BookByNameView' object has no attribute 'object'.
I've tried ListView as well and received several other errors along the way. The get_success_url also needs to take in a primary key and I can't figure out how to get that passed in as well. Again, I'm a 3 month Django newbie so please be gentle and thanks in advance for your thoughts and suggestions! I feel like I'm in the ballpark...just can't find my seat! I'm very open to doing this differently, if there's a cleaner/better way to do this!
Based on the latest feedback, it would appear the Class Based View should look like:
class BookNameView(FormView):
form_class = BookName
template_name = 'library/book_list.html'
def get_success_url(self, *args):
return reverse_lazy('library:book_detail')
Is this correct? I ran a test version of this and in response to your question as to why I am using self.object.id at all, I am trying to get the pk from the modelchoicefield that I am using to return the view I am trying to get. This may be where I am getting a bit lost. I am trying to get the detail view from the modelchoicefield dropdown, and return the book that is selected. However, I can't seem to pass the pk to this view successfully.
I updated my code to...
class BookByNameView(FormView, ListView):
model = Book
form_class = BookByName
template_name = 'library/book_list.html'
def get_success_url(self, *args):
return reverse_lazy('library:book_detail')
But now it says error...Reverse for 'book_detail' with no arguments not found.
Why are you using self.object there at all? You used form.cleaned_data in the original view, that's what you should use in the class based version too. Note that the form is passed to form_valid.
Note that you've done lots of other weird things too. Your getmethod is pointless, as is your definition of the initial dict; you should delete them both. Also, FormView already inherits from View, there's no need to have View in your declaration explicitly.
You can override the form_valid() function in FormView to achieve what you want. If the form is valid then it is passed to the form_valid() function.
Try this:
class BookByNameView(FormView):
model = Book
form_class = BookByName
template_name = 'library/book_list.html'
def form_valid(self, form):
bookbyname = form.cleaned_data['dropdown']
return HttpResponseRedirect(bookbyname.get_absolute_url())
I am new to django class based views and may be the way I am approaching this is a little naive, so I would appreciate if you could suggest a better way.
So my problem is here:
There are three types of users in my project. 1. Student, 2. Teacher, 3. Parent. I need to be able to show different user settings pertaining to each type of user when the user requests the settings page in their respective forms. Also, I need to be able to save the data into the respective tables as the user submits the form.
I have a class based view (UserSettingsView):
class UserSettingsView(LoginRequiredMixin, FormView):
success_url = '.'
template_name = 'accts/usersettings.html'
def get_initial(self):
if self.request.user.is_authenticated():
user_obj = get_user_model().objects.get(email=self.request.user.email)
if user_obj.profile.is_student:
return {
'first_name': user_obj.profile.first_name,
'last_name': user_obj.profile.last_name,
""" and other student field variables """
}
if user_obj.profile.is_teacher:
return {
""" Teacher field variables """
}
else:
return render_to_response('allauth/account/login.html')
def form_valid(self, form):
messages.add_message(self.request, messages.SUCCESS, 'Settings Saved!')
return super(UserSettingsView, self).form_valid(form)
def get_context_data(self, **kwargs):
context = super(UserSettingsView, self).get_context_data(**kwargs)
context['user'] = get_user_model().objects.get(email=self.request.user.email)
context['userprofile'] = UserProfile.objects.get(user_id=context['user'])
return context
def post(self, request, *args, **kwargs):
form_class = self.get_form_class()
form = self.get_form(form_class)
form.full_clean()
if form.is_valid():
user = request.user
user.profile.first_name = form.cleaned_data['first_name']
user.profile.last_name = form.cleaned_data['last_name']
user.profile.save()
if user.profile.is_student:
""" update student database """
user.save()
user.student.save()
if user.profile.is_teacher:
""" update teacher database """
user.save()
user.teacher.save()
return self.form_valid(form)
else:
return self.form_invalid(form)
Different instances of Usersettings view are called using the pick_settings generic view.
url(regex=r'^profilesettings/',view=pick_settings,name='profilesettings'),
And here is the pick_settings view:
def pick_settings(request):
if request.user.is_authenticated():
if request.method == 'GET':
if request.user.profile.is_student:
return UserSettingsView.as_view(form_class=StudentSettingsForm)(request)
if request.user.profile.is_teacher:
return UserSettingsView.as_view(form_class=TeacherSettingsForm)(request)
if request.user.profile.is_parent:
return UserSettingsView.as_view(form_class=ParentSettingsForm)(request)
else:
if request.method == 'POST':
"""
return ***<--- I need to know what to pass here to be able to call the appropriate post function of the UserSettingsView?---->"""***
else:
return HttpResponseRedirect('/accounts/login/')
I need to be able to call the post function of the UserSettingsView. May be using the get_context_data? But I am not sure how.
Again it will be great, if someone could suggest a better way because I am pretty sure this might be violating the DRY principle. Although, I am not too concerned with that as long as the job gets done as I am running a deadline. :) Thanks!
FormView has a method get_form_class(). It is called from get() and post(), so self.request will already be set (as will be self.request.user). Consequently,
class UserSettingsView(LoginRequiredMixin, FormView):
[...]
def get_form_class(self):
# no need to check is_authenticated() as we have LoginRequiredMixin
if request.user.profile.is_student:
return StudentSettingsForm
elif user.profile.is_teacher:
return TeacherSettingsForm
elif user.profile.is_parent:
return ParentSettingsForm
This should already to the trick as you get the correct form for each user type.
If you also need to render different templates, override get_template_names():
def get_template_names(self):
if request.user.profile.is_student:
return ['myapp/settings/student.html']
elif user.profile.is_teacher:
return ['myapp/settings/teacher.html']
elif user.profile.is_parent:
return ['myapp/settings/parent.html']
DRY can be achieved using proper inheritance in the templates combining common template fragments.
And lest I forget (I already forgot): To get rid of the if in the post() method of your view, simple override the save() method of you forms which I assume are ModelForms, anyway.
again, apologies for what is probably a straightforward question!
Ok, so!
my problem is i have a saveModel function, where it saves a model. If the model is all good (is_valid), it will save the model and redirect to pageA
if the model is bad, or the request is a GET, then i'd like to redirect to pageB
all well and good, but i do this several times, how annoying! I don't want to cut and paste all the time, so i came up with this:
class SaveModel(View):
def as_view(self):
if request.method == "POST":
form = SaveModel.getPostForm(self.request)
if form.is_valid():
processedForm = SaveModel.processForm(self.request)
processedForm.save()
if (self.success_template):
return render_to_response(self.success_template)
else:
return render_to_response('pageA.html')
else:
form = SaveModel.getForm()
if (self.context_object_name):
contextName = context_object_name
else:
contextName = 'form'
if (self.template_name):
return render_to_response(template_name,{contextName:form})
else :
return render_to_response('pageB.html',{contextName:form})
def getForm(self):
return None
def getPostForm(self,request):
return None
def processForm(self,form,request):
return None
THEN, i define other classes to handle particular models, like, for example, so:
class StoryModelView(SaveModel):
def getForm(self,request):
return StoryForm()
def getPostForm(self,request):
return StoryForm(request.POST)
def processForm(self,form,request):
theStory = form.save(commit=False)
theStory.user = request.user
return theStory
and then, finally, in my urls.py i will refer to (as above) the model to use like so:
url(r'^addStory/$',
StoryModelView.as_view(
context_object_name='form',
template_name='accounts/addStory.html',
success_template='accounts/addStorySuccess.html'
)
),
This doesn't seem to work though - pycharm assures me that my references to self.context_object_name and so on are invalid. I'm v. new to python and django (which is why i thought i'd build a website with them! clever andrew!), so i am sure that i've missed a whole bunch of things (abstract methods and stuff... python does that, right?)
what do i need to do to get this all working? Is this how i should be doing things?
ANSWER BY ME!
Ok, so the comments everyone has written about the CreateView are probably correct. "Probably" because i never ended up using it, because i ended up sticking with my code instead.
In case anybody is, like me, new to python and django and wants to see how the whole thing works, here we are!
class SaveModel(View):
success_template = None
context_object_name = None
template_name = None
def post(self, request):
form = self.getPostForm(self.request)
if form.is_valid():
processedForm = self.processForm(form,self.request)
processedForm.save()
if self.success_template:
return render_to_response(self.success_template)
else:
return render_to_response('accounts/addStorySuccess.html')
else:
self.renderValidations(form)
def get(self,request):
form = self.getForm()
self.renderValidations(form)
def renderValidations(self,form):
if self.context_object_name:
contextName = self.context_object_name
else:
contextName = 'form'
if self.template_name:
return render_to_response(self.template_name,{contextName:form})
else :
return render_to_response('accounts/addStory.html',{contextName:form})
def getForm(self):
return None
def getPostForm(self,request):
return None
def processForm(self,form,request):
return None
and that is the main class, then i can override it like so:
class StoryModelView(SaveModel):
def getForm(self):
return StoryForm()
def getPostForm(self,request):
return StoryForm(request.POST)
def processForm(self,form,request):
theStory = form.save(commit=False)
theStory.user = request.user
return theStory
i tripped myself up with how "self" works in python a few times. it seems to be magically sent across with all method calls, but you need it as the first arg in the method declaration (but you never need to use it when calling/using the method)
i think there's only post or get for methods when overriding the View class. i don't have a good idea of the "process" of the call, or what the order is, dispatch was mentioned as something to override, but i suspect that is only where i need to change when/how to deal with differing request types (GET, POST, HEAD etc)
oh! the urls.py!
url(r'^addStory/$',
StoryModelView.as_view(
context_object_name='form',
template_name = 'accounts/addStory.html',
success_template= 'accounts/addStorySuccess.html'
)
),
i can just chuck whatever i want into that "as_view" call, and then, as long as those parameters are defined in the overriding class it's all good.
so yay! my classes all work and women want me. use my code, and this can happen to you too!*
*results atypical and fictional. your results may differ.