Custom UpdateView in Python - django

I am trying to get a custom UpdateView to work in Python/Django. I believe that the code that I've writtten is mostly correct, as it seems to be returning the proper Primary Key ID in the URL when I click on the associated dropdown. The problem is that I am not seeing any of the data associated with this record on the screen in update mode. The screen appears in edit mode, but there is no data. I suspect the problem is perhaps the django template in the html form? However, I have played with the form and used {{ form }} and it too returns a blank form. I've played with this all afternoon and I'm out of guesses. Here is my view:
def updating_document(request, pk):
doc = get_object_or_404(Doc, pk=pk)
form = Update_Doc_Form(request.user, request.POST)
if request.method == 'GET':
if form.is_valid():
form.save()
return HttpResponseRedirect(reverse('App:main_procedure_menu'))
else:
print("Form is invalid!")
return render(request,'Doc/update_doc.html',{'form':form })
I also have an associated form...
Form.py
class Update_Doc_Form(forms.ModelForm):
class Meta:
model = Doc
exclude = ['user']
doc_name = forms.CharField(widget=forms.TextInput)
description = forms.CharField(required=True,widget=forms.Textarea)
team = forms.CharField(widget=forms.Select)
document = forms.CharField(required=True,widget=forms.Textarea)
def __init__(self, *args, **kwargs):
super(Update_Doc_Form, self).__init__(*args, **kwargs)
self.fields['doc_name'].widget.attrs['class'] = 'name'
self.fields['description'].widget.attrs['class'] = 'description'
self.fields['team'].widget.attrs['class'] = 'choices'
self.fields['team'].empty_label = ''
I'm a newbie, but I do want to use a custom UpdateView so that I can alter some of the fields and pass user information. I feel like the code is close, just need to figure out why it's not actually populating the form with data. Thanks in advance for your help!

What a difference a day makes. Found an answer on SO this morning. Not sure how to credit the person or issue number....
The answer was to add the following line of code to my form:
user = kwargs.pop('object_user')
I also needed to add the following function to my View:
def get_form_kwargs(self):
kwargs = super(ViewName,self).get_form_kwargs()
kwargs.update({'object_user':self.request.user})
return kwargs
This question was answered originally in 2013 by Ivan ViraByan. Thanks Ivan!
I ultimately went with a standard class based UpdateView and scrapped my plans for the custom UpdateView once I was able to figure out how to use the Class Based View(UpdateView) and "pop" off the user information when passing it to the form based on Ivan ViraByan's answer in 2013.
The code above allows you to get the user but not pass it to the ModelForm so that you don't get the unexpected user error.

Related

How to update data in Django when getting unique field error

first thing first I'm sorry for my bad english. I hope so u can understand me easily.
I'm trying to make a blog with django but there's a place I can't solve. I used unique slug field instead of id for url, whenever I want to update the data I get the UNIQUE constraint failed: post_post.url_text error (url_text is slugfield variable name). Here is the my model,
and the Form looks like this,
At first I followed a way to update the data here:
#login_required(login_url='login')
def post_update(request, url_text=None):
post = get_object_or_404(Post, url_text=url_text)
form = PostWrite(request.POST or None, instance=post)
if form.is_valid():
post_author = request.user
post_title = form.cleaned_data.get('post_title')
post_content = form.cleaned_data.get('post_content')
post_tags = form.cleaned_data.get('tags')
post = Post(post_author=post_author, post_title=post_title, post_content=post_content, tags=post_tags)
post.save()
context = {
'post': post,
'form': form,
}
return render(request, 'post/re_write.html', context)
and I got the error I mentioned at the beginning of the post. Then I found a solution like this in the forums,
if form.is_valid():
form.save()
This time it does not give any error but does not update the data. Despite hours of research, for some reason I could not find a tangible solution. I wanted to ask you esteemed coders as a last resort and I look forward to your help.
The issue is that you're creating a new post with the following code while this view appears to be an update:
post = Post(post_author=post_author, post_title=post_title, post_content=post_content, tags=post_tags)
post.save()
Instead, you should utilize the modelform you're already using to save the changes to the instance:
if form.is_valid():
post = form.save()
I'm guessing maybe because you weren't capturing the post from form.save() the rendered template appeared to not have the data updated because the instance passed into the template was from before the changes.
Other issue:
You're overriding the save method, but not always calling super().save. This means that you're only saving the post when the url_text property is not set. Instead always call super().save
def save(self, *args, **kwargs):
if ...
# other stuff
super().save(*args, **kwargs)

Django conditional field display on form

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

Django - retrieve the form input values

I'm working in a Create view and I'm trying to overwrite the form_valid method. My goal is to create a record in another table before creating in the current model.
For instance, my form has a field called name. My question is how can I retrieve this fields value within the form_valid method. A piece of code to help you understand my question:
class DeliveryCreateView(CreateView):
model = Delivery
form_class = DeliveryForm
def form_valid(self, form):
response = super(DeliveryCreateView, self).form_valid(form)
name = form["Name"] # I know this is wrong. That's the part I don't know how to do.
self.object.permissions.add(self.request.user)
self.object.save()
return response
Thanks for any help
I just realized I can use the current object, like this:
self.object.name
This gives me the name, this object if filled with all the information.

django form errors before submit

My django form has errors in the initial page load, before the form even has a chance to be submitted.
My view:
def example_function(request):
if request.method == 'POST':
# the request is GET
else:
form = MyForm(user=request.user)
import pdb;pdb.set_trace()
return render_to_response('templates/example.html', locals(), context_instance=RequestContext(request),)
Where I have my pdb imported, in the console I can see that my form already has errors. The output of form.errors in my console is all the fields in the model which are set to not null.
(Pdb) form.errors
{'example_field_1': [u'This field is required.'], 'example_field_2': [u'This field is required.']}
The form has not submit yet, but I am still getting errors. Can someone explain?
I'm using django 1.4.
My form:
class MyForm(forms.ModelForm):
captcha = ReCaptchaField()
_readonly_template = form.TextInput(attrs={'readonly':'readonly'})
first_name = forms.CharField(widget = _readonly_tempalte)
def __init__(self, data=None, *args, **kwargs):
data = data or {}
if 'user' in kwargs:
user = kwargs['user']
del kwargs['user']
data.update({
'first_name' : user.first_name,
})
super(MyForm, self).__init__(data, *args, **kwargs)
class Meta:
model = MyModel
My model:
class MyModel(models.Model):
first_name = models.CharField(max_length=255)
example_field_1 = models.CharField(max_length=255)
example_field_2 = models.CharField(max_length=255)
https://docs.djangoproject.com/en/1.8/ref/forms/validation/
accessing the form.errors attribute will trigger the various form validation methods. Those errors shouldn't show up when you render the form.
I'm not sure how the user field is structured, but keep in mind that if you want the user name, you may want to change that from request.user to request.user.username.
I hope you resolved your issue, but in case you haven't, I had a similar issue which I was able to resolve by using "or None" when setting the form after checking if it is a POST (or GET) request.
In your case it looks like this may be a slightly different issue, but I wondered if this snippet might fix things up:
if request.method == "POST":
form = MyForm(request.POST or None)
# .. do stuff....
else: #.....this is a GET
data = {'user': request.user.username} #note this is changed to username
form = MyForm(data)
Not sure if still useful, but adding it here, as I just ran into this for my ChoiceField items within my form.
I was getting the same error messages, but eventually found out I had forgotten to ad 'or None' when initiating the form inside my view.
The initial code inside my view function that was displaying the error messages from the start:
form=FormName(request.POST)
I just added the 'or None' to it:
form=FormName(request.POST or None)
And all good after that.
Don't you need to do something like this
form = NameForm(request.POST)
Rather then attempting to use the user object to populate the form? Will the user object have an example_field_1 in it?
https://docs.djangoproject.com/en/1.8/topics/forms/
This is the normal behavior.
Some properties of fields are checked on client side. The error messages belong to the form, are part of the html but are not displayed until needed. It saves a client-server request.

Django form: ask for confirmation before committing to db

Update: The solution can be found as a separate answer
I am making a Django form to allow users to add tvshows to my db. To do this I have a Tvshow model, a TvshowModelForm and I use the generic class-based views CreateTvshowView/UpdateTvshowView to generate the form.
Now comes my problem: lets say a user wants to add a show to the db, e.g. Game of Thrones. If a show by this title already exists, I want to prompt the user for confirmation that this is indeed a different show than the one in the db, and if no similar show exists I want to commit it to the db. How do I best handle this confirmation?
Some of my experiments are shown in the code below, but maybe I am going about this the wrong way. The base of my solution is to include a hidden field force, which should be set to 1 if the user gets prompted if he is sure he wants to commit this data, so that I can read out whether this thing is 1 to decide whether the user clicked submit again, thereby telling me that he wants to store it.
I would love to hear what you guy's think on how to solve this.
views.py
class TvshowModelForm(forms.ModelForm):
force = forms.CharField(required=False, initial=0)
def __init__(self, *args, **kwargs):
super(TvshowModelForm, self).__init__(*args, **kwargs)
class Meta:
model = Tvshow
exclude = ('user')
class UpdateTvshowView(UpdateView):
form_class = TvshowModelForm
model = Tvshow
template_name = "tvshow_form.html"
#Only the user who added it should be allowed to edit
def form_valid(self, form):
self.object = form.save(commit=False)
#Check for duplicates and similar results, raise an error/warning if one is found
dup_list = get_object_duplicates(Tvshow, title = self.object.title)
if dup_list:
messages.add_message(self.request, messages.WARNING,
'A tv show with this name already exists. Are you sure this is not the same one? Click submit again once you\'re sure this is new content'
)
# Experiment 1, I don't know why this doesn't work
# form.fields['force'] = forms.CharField(required=False, initial=1)
# Experiment 2, does not work: cleaned_data is not used to generate the new form
# if form.is_valid():
# form.cleaned_data['force'] = 1
# Experiment 3, does not work: querydict is immutable
# form.data['force'] = u'1'
if self.object.user != self.request.user:
messages.add_message(self.request, messages.ERROR, 'Only the user who added this content is allowed to edit it.')
if not messages.get_messages(self.request):
return super(UpdateTvshowView, self).form_valid(form)
else:
return super(UpdateTvshowView, self).form_invalid(form)
Solution
Having solved this with the help of the ideas posted here as answers, in particular those by Alexander Larikov and Chris Lawlor, I would like to post my final solution so others might benefit from it.
It turns out that it is possible to do this with CBV, and I rather like it. (Because I am a fan of keeping everything OOP) I have also made the forms as generic as possible.
First, I have made the following forms:
class BaseConfirmModelForm(BaseModelForm):
force = forms.BooleanField(required=False, initial=0)
def clean_force(self):
data = self.cleaned_data['force']
if data:
return data
else:
raise forms.ValidationError('Please confirm that this {} is unique.'.format(ContentType.objects.get_for_model(self.Meta.model)))
class TvshowModelForm(BaseModelForm):
class Meta(BaseModelForm.Meta):
model = Tvshow
exclude = ('user')
"""
To ask for user confirmation in case of duplicate title
"""
class ConfirmTvshowModelForm(TvshowModelForm, BaseConfirmModelForm):
pass
And now making suitable views. The key here was the discovery of get_form_class as opposed to using the form_class variable.
class EditTvshowView(FormView):
def dispatch(self, request, *args, **kwargs):
try:
dup_list = get_object_duplicates(self.model, title = request.POST['title'])
if dup_list:
self.duplicate = True
messages.add_message(request, messages.ERROR, 'Please confirm that this show is unique.')
else:
self.duplicate = False
except KeyError:
self.duplicate = False
return super(EditTvshowView, self).dispatch(request, *args, **kwargs)
def get_form_class(self):
return ConfirmTvshowModelForm if self.duplicate else TvshowModelForm
"""
Classes to create and update tvshow objects.
"""
class CreateTvshowView(CreateView, EditTvshowView):
pass
class UpdateTvshowView(EditTvshowView, UpdateObjectView):
model = Tvshow
I hope this will benefit others with similar problems.
I will post it as an answer. In your form's clean method you can validate user's data in the way you want. It might look like that:
def clean(self):
# check if 'force' checkbox is not set on the form
if not self.cleaned_data.get('force'):
dup_list = get_object_duplicates(Tvshow, title = self.object.title)
if dup_list:
raise forms.ValidationError("A tv show with this name already exists. "
"Are you sure this is not the same one? "
"Click submit again once you're sure this "
"is new content")
You could stick the POST data in the user's session, redirect to a confirmation page which contains a simple Confirm / Deny form, which POSTs to another view which processes the confirmation. If the update is confirmed, pull the POST data out of the session and process as normal. If update is cancelled, remove the data from the session and move on.
I have to do something similar and i could do it using Jquery Dialog (to show if form data would "duplicate" things) and Ajax (to post to a view that make the required verification and return if there was a problem or not). If data was possibly duplicated, a dialog was shown where the duplicated entries appeared and it has 2 buttons: Confirm or Cancel. If someone hits in "confirm" you can continue with the original submit (for example, using jquery to submit the form). If not, you just close the dialog and let everything as it was.
I hope it helps and that you understand my description.... If you need help doing this, tell me so i can copy you an example.
An alternative, and cleaner than using a vaidationerror, is to use Django's built in form Wizard functionality: https://django-formtools.readthedocs.io/en/latest/wizard.html
This lets you link multiple forms together and act on them once they are all validated.