Django Generic Model Formsets - django

So I have a site where users are capable of registering devices and then registering commands to those devices. These commands have an associated widget (button, slider, etc) that determine the unique properties that the command has.
I am trying to figure out the most generic way to use the model formsets in my application. I have things working, where I create a model_formset for each ModelForm, and get data from each model to place in the formset, and then show it in my template.
What I would really like to do is something like this:
command_formset = modelformset_factory(Command, extra=0, fields='__all__')
formset = command_formset(queryset=Command.objects.filter(device_id=device_id))
Where I get all of my commands (which returns both buttons and sliders) and then make a single command_formset, which has all command objects.
In this case it does part of what I am looking for, where I can query my model and get all button and slider commands, but the formset only includes the fields from command - so the min and max value for the slider are lost.
Is something like this possible? Here is my more complete code:
Models
class Command(models.Model):
command_name = models.CharField(max_length=100)
command = models.CharField(max_length=100)
command_url = models.CharField(max_length=100)
command_type = models.CharField(max_length=100)
device = models.ForeignKey(Device, on_delete=models.CASCADE, default=1) # Each command has one device
def __str__(self):
return self.command_name
class ButtonCommand(Command):
button_color = models.CharField()
class SliderCommand(Command):
min_value = models.IntegerField()
max_value = models.IntegerField()
Forms
class CommandForm(ModelForm):
class Meta:
model = Command
fields = '__all__'
def __init__(self, *args, **kwargs):
super().__init__(*args, **kwargs)
for field in iter(self.fields):
self.fields[field].widget.attrs.update({'class': 'form-control'})
class ButtonCommandForm(ModelForm):
class Meta:
model = ButtonCommand
fields = '__all__'
def __init__(self, *args, **kwargs):
super().__init__(*args, **kwargs)
for field in iter(self.fields):
self.fields[field].widget.attrs.update({'class': 'form-control'})
class SliderCommandForm(ModelForm):
class Meta:
model = SliderCommand
fields = '__all__'
def __init__(self, *args, **kwargs):
super().__init__(*args, **kwargs)
for field in iter(self.fields):
self.fields[field].widget.attrs.update({'class': 'form-control'})
View
command_formset = modelformset_factory(Command, extra=0, fields='__all__')
button_command_formset = modelformset_factory(ButtonCommand, form=ButtonCommandForm, extra=0,
fields=('command_name', 'command', 'command_type', 'command_url'))
slider_command_formset = modelformset_factory(SliderCommand, extra=0,
fields=('command_name', 'command', 'command_type', 'command_url',
'min_value', 'max_value'))
device_form = DeviceForm(initial=device)
formset = command_formset(queryset=Command.objects.filter(device_id=device_id))
button_formset = button_command_formset(queryset=ButtonCommand.objects.filter(device_id=device_id),
prefix="button_form")
slider_formset = slider_command_formset(queryset=SliderCommand.objects.filter(device_id=device_id),
prefix="slider_form")
Edit Additional View Code
template = 'device_control/device_management.html'
return TemplateResponse(request, template, {'device': device,
'device_form': device_form,
'button_formset': button_formset,
'slider_formset': slider_formset,
'formset' : formset})
Another Related Question
input_type = request.POST['command_type']
if input_type == 'button':
form = ButtonCommandForm(request.POST)
elif input_type == 'slider':
form = SliderCommandForm(request.POST)
else:
form = None
Hopefully I am not overwhelming, but the above is a very similar question that seems much simpler. User posts a form, both of which inherit from Command. While the above is quite simple, if I eventually have 20+ different types of CommandForms, this will get fairly nasty.
I am really hoping that I am missing some way that Django can tell which child form should be used to build the form.

Related

Django: how to filter form field based off foreignkey AND many to many relationship?

Currently, when a user creates a task, they can assign it to all users. I only want them to be able to assign a task based on the members of the project. I feel like the concept I have right now works but I need to replace the ????. Task's assignee has a foreignkey relationship with the user_model. The user_model is also connected with members on a many to many relationship.
projects/models.py
class Project(models.Model):
name = models.CharField(max_length=200)
description = models.TextField()
members = models.ManyToManyField(USER_MODEL, related_name="projects")
tasks/models.py
class Task(models.Model):
name = models.CharField(max_length=200)
start_date = models.DateTimeField()
due_date = models.DateTimeField()
is_completed = models.BooleanField(default=False)
project = models.ForeignKey(
"projects.Project", related_name="tasks", on_delete=models.CASCADE
)
assignee = models.ForeignKey(
USER_MODEL, null=True, related_name="tasks", on_delete=models.SET_NULL
)
tasks/views.py
class TaskCreateView(LoginRequiredMixin, CreateView):
model = Task
template_name = "tasks/create.html"
# fields = ["name", "start_date", "due_date", "project", "assignee"]
form_class = TaskForm
def get_form_kwargs(self):
kwargs = super(TaskCreateView, self).get_form_kwargs()
kwargs["user"] = self.request.user
kwargs["project_members"] = ??????????
return kwargs
tasks/forms.py
class TaskForm(ModelForm):
class Meta:
model = Task
fields = ["name", "start_date", "due_date", "project", "assignee"]
def __init__(self, *args, **kwargs):
user = kwargs.pop("user")
project_members = kwargs.pop("project_members")
super(TaskForm, self).__init__(*args, **kwargs)
self.fields["project"].queryset = Project.objects.filter(members=user)
self.fields["assignee"].queryset = Project.objects.filter(
members=?????????
)
Update:
I followed SamSparx's suggestions and changed the URL paths so now TaskCreateView knows which project id. I updated my tasks/views to the following but I get a TypeError: "super(type, obj): obj must be an instance or subtype of type" and it points to the line: form = super(TaskForm, self).get_form(*args, **kwargs) Maybe it has something to do with having a get_form_kwargs and get_form function? I kept my existing features for the custom form such as when a user creates a task, they can only select projects they are associated with.
Views.py updated
class TaskCreateView(LoginRequiredMixin, CreateView):
model = Task
template_name = "tasks/create.html"
form_class = TaskForm
def get_form_kwargs(self):
kwargs = super(TaskCreateView, self).get_form_kwargs()
kwargs["user"] = self.request.user
return kwargs
def get_form(self, *args, **kwargs):
form = super(TaskForm, self).get_form(*args, **kwargs)
form.fields["assignee"].queryset = Project.members.filter(
project_id=self.kwargs["project_id"]
)
def form_valid(self, form):
form.instance.project_id = Project.self.kwargs["project_id"]
return super(TaskCreateView, self).form_valid(form)
def get_success_url(self):
return reverse_lazy("list_projects")
I have also tried to update the forms.py with the following but get an error that .filter cannot be used on Many to Many relationships.
Updated forms.py
class TaskForm(ModelForm):
class Meta:
model = Task
fields = ["name", "start_date", "due_date", "project", "assignee"]
def __init__(self, *args, **kwargs):
user = kwargs.pop("user")
super(TaskForm, self).__init__(*args, **kwargs)
self.fields["project"].queryset = Project.objects.filter(members=user)
self.fields["assignee"].queryset = Project.members.filter(
project_id=self.kwargs["project_id"]
)
Another thing I have tried is to go back to my first approach now that I have the url paths: tasks/create/(project_id)
Views.py
class TaskCreateView(LoginRequiredMixin, CreateView):
model = Task
template_name = "tasks/create.html"
form_class = TaskForm
def get_form_kwargs(self):
kwargs = super(TaskCreateView, self).get_form_kwargs()
kwargs["user"] = self.request.user
kwargs["project_id"] = Project.objects.all()[0].members.name
# prints to auth.User.none
return kwargs
I feel like if the kwargs["project_id"] line can be changed to getting list of members of whatever project with the ID in the URL, then this should solve it
Forms.py
class TaskForm(ModelForm):
class Meta:
model = Task
fields = ["name", "start_date", "due_date", "project", "assignee"]
def __init__(self, *args, **kwargs):
user = kwargs.pop("user")
project_id = kwargs.pop("project_id")
super(TaskForm, self).__init__(*args, **kwargs)
self.fields["project"].queryset = Project.objects.filter(members=user)
self.fields["assignee"].queryset = Project.objects.filter(
members=project_id
)
The problem here is that your task doesn't know what members are relevant to include as assignees until you have chosen the project the task belongs to, and both project and assignee are chosen in the same form, so Django doeesn't know who is relevant yet.
The easiest way to handle this is to ensure the call to create a task is associated with the project it is going to be for - eg,
Update your URLs to handle the project ID
Path('create-task/<int:project_id>', TaskCreateView.as_view(), name='create_task')
Update your view
class TaskCreateView(LoginRequiredMixin, CreateView):
model = Task
template_name = "tasks/create.html"
# fields = ["name", "start_date", "due_date", "assignee"]
#NB: I have remove project from the field list, you may need to do the same in your form as it is handled elsewhere
form_class = TaskForm
def get_form(self, *args, **kwargs):
form = super(TaskCreateView, self).get_form(*args, **kwargs)
form.fields['assignee'].queryset = Project.members.filter(project_id = self.kwargs['project_id'])
Return form
def form_valid(self, form):
form.instance.project_id = project.self.kwargs['project_id']
return super(TaskCreateView, self).form_valid(form)
Add links
Create Task for this project
This will create a link on the project details page, or underneath the project in a listview to 'create task for this project', carrying the project informaton for the view via the URL. Otherwise you will have to get into some rather more complex ajax calls that populate the potential assignees list based on the selection within the project dropdown in a dynamic fashion

Limit the Choices shown from ManyToMany ForeignKey

How do I limit the values returned via the ManyToMany relationship and thus displayed in the <SELECT> field on my form to only show the spots which were created by the currently logged in user?
models.py
class Project(models.Model):
owner = models.ForeignKey(User, editable=False)
...
spots = models.ManyToManyField(to='Spot', blank=True, )
class Spot(models.Model):
owner = models.ForeignKey(User, editable=False)
spot_name = models.CharField(max_length=80, blank=False)
forms.py
from django import forms
from .models import Project, Spot
class ProjectForm(forms.ModelForm):
class Meta:
model = Project
exclude = ('owner', )
class SpotForm(forms.ModelForm):
class Meta:
model = Spot
exclude = ('owner', )
I'm using GenericViews for Update and Create and currently see all of the entries everyone has made into Spots when I'm updating or creating a Project. I want to see only the entries entered by the logged in user. For completeness sake, yes, the project.owner and spot.owner were set to User when they were created.
I've tried def INIT in the forms.py and using limit_choices_to on the manytomany field in the model. Either I did those both wrong or that's not the right way to do it.
thank you!
in your forms.py
class ProjectForm(forms.ModelForm):
class Meta:
model = Project
exclude = ('owner', )
def __init__(self, user_id, *args, **kwargs):
self.fields['spots'] = forms.ModelChoiceField(widget=forms.Select, queryset=Project.objects.filter(owner=user_id))
class SpotForm(forms.ModelForm):
class Meta:
model = Spot
exclude = ('owner', )
def __init__(self, user_id, *args, **kwargs):
self.fields['spot_name'] = forms.ModelChoiceField(widget=forms.Select, queryset=Spot.objects.filter(owner=user_id))
in your views.py
user_id = Project.objects.get(owner=request.user).owner
project_form = ProjectForm(user_id)
spot_form = SpotForm(user_id)
As I mentioned above, Dean's answer was really close, but didn't work for me. Primarily because request is not accessible in the view directly. Maybe it is in older Django versions? I'm on 1.9. Thank you Dean, you got me over the hump!
The gist of what's going on is adding User into the kwargs in the View, passing that to the ModelForm, remove User from the kwargs and use it to filter the Spots before the form is shown.
This is the code that worked for my project:
views.py
class ProjectUpdate(UpdateView):
model = Project
success_url = reverse_lazy('projects-mine')
form_class = ProjectForm
def dispatch(self, *args, **kwargs):
return super(ProjectUpdate, self).dispatch(*args, **kwargs)
def get_form_kwargs(self):
kwargs = super(ProjectUpdate, self).get_form_kwargs()
kwargs.update({'user': self.request.user})
return kwargs
forms.py
class ProjectForm(forms.ModelForm):
class Meta:
model = Project
exclude = ('owner', 'whispir_id')
def __init__(self, *args, **kwargs):
user_id = kwargs.pop('user')
super(ProjectForm, self).__init__(*args, **kwargs)
self.fields['spots'] = forms.ModelMultipleChoiceField(queryset=Spot.objects.filter(owner=user_id))
class SpotForm(forms.ModelForm):
class Meta:
model = Spot
exclude = ('owner', )
def __init__(self, *args, **kwargs):
user_id = kwargs.pop('user')
super(SpotForm, self).__init__(*args, **kwargs)
self.fields['spot_name'] = forms.ModelMultipleChoiceField(queryset=Spot.objects.filter(owner=user_id))

Choices lost when overriding Django Select with RadioSelect

Given the django model below, is it possible to automatically update a subset of the fields to be RadioSelect instead of the default Select?
class ExampleModel(models.Model):
field1_radios = models.CharField(max_length=1, choices=DEFAULT_CHOICES)
field2_radios = models.CharField(max_length=1, choices=DEFAULT_CHOICES)
field3_radios = models.CharField(max_length=1, choices=DEFAULT_CHOICES)
field4_radios = models.CharField(max_length=1, choices=DEFAULT_CHOICES)
field5 = models.CharField(max_length=50)
...
I can achieve this manually with:
class ExampleForm(forms.ModelForm):
class Meta:
model = ExampleModel
widgets = {
'field1_radios': forms.RadioSelect(),
'field2_radios': forms.RadioSelect(),
'field3_radios': forms.RadioSelect(),
'field4_radios': forms.RadioSelect()}
When I try to automate the creation of the widgets the choices are lost (and the radio buttons are not rendered):
def custom_callback(f, *args, **kwargs):
if f.name.endswith('_radios'):
formfield = f.formfield()
formfield.widget = forms.RadioSelect()
return formfield
else:
return f.formfield()
class ExampleForm(forms.ModelForm):
formfield_callback = custom_callback
class Meta:
model = ExampleModel
ahh, it looks like I was missing the final step of re-specifying the original choices, this is not done automatically:
def custom_callback(f, *args, **kwargs):
if f.name.endswith('_radios'):
formfield = f.formfield()
formfield.widget = forms.RadioSelect(choices=formfield.choices)
return formfield
else:
return f.formfield()
I haven't seen formfield_callback used very often, and I don't think it's documented.
Another approach would be to override formfield_for_choice_field.
class MyModelAdmin(admin.ModelAdmin):
...
def formfield_for_choice_field(self, db_field, request, **kwargs):
"""Use a radio select instead of a select box"""
kwargs['widget'] = forms.RadioSelect
if 'choices' not in kwargs:
# this was required to prevent displaying the empty label ---------
kwargs['choices'] = db_field.get_choices(include_blank=False)
return super(MyModelAdmin, self).formfield_for_choice_field(db_field, request, **kwargs)

Django How to override a child form in inlineformset_factory

I'm trying to override concept queryset in my child form, to get a custom list concepts based on the area got from request.POST, here is my list of concepts, which i need to filter based on the POST request, this lists is a fk of my child form (InvoiceDetail). is it possible to have these filters?
after doing some test when I pass the initial data as the documentation says initial=['concept'=queryset_as_dict], it always returns all the concepts, but i print the same in the view and its ok the filter, but is not ok when i render in template, so I was reading that I need to use some BaseInlineFormset. so when I test I obtained different errors:
django.core.exceptions.ValidationError: ['ManagementForm data is missing or has been tampered with']
'InvoiceDetailFormFormSet' object has no attribute 'fields'
so here is my code:
models.py
class ConceptDetail(CreateUpdateMixin): # here, is custom list if area='default' only returns 10 rows.
name = models.CharField(max_length=150)
area = models.ForeignKey('procedure.Area')
class Invoice(ClusterableModel, CreateUpdateMixin): # parentForm
invoice = models.SlugField(max_length=15)
class InvoiceDetail(CreateUpdateMixin): # childForm
tax = models.FloatField()
concept = models.ForeignKey(ConceptDetail, null=True, blank=True) # fk to override using custom queryset
invoice = models.ForeignKey('Invoice', null=True, blank=True)
views.py
class CreateInvoiceProcedureView(LoginRequiredMixin, PermissionRequiredMixin, CreateView):
template_name = 'invoice/invoice_form.html'
model = Invoice
permission_required = 'invoice.can_check_invoice'
def post(self, request, *args, **kwargs):
self.object = None
form = InvoiceForm(request=request)
# initial initial=[{'tax': 16, }] removed
invoice_detail_form = InvoiceDetailFormSet(request.POST, instance=Invoice,
request=request)
return self.render_to_response(
self.get_context_data(
form=form,
invoice_detail_form=invoice_detail_form
)
)
forms.py
class BaseFormSetInvoice(BaseInlineFormSet):
def __init__(self, *args, **kwargs):
# call first to retrieve kwargs values, when the class is instantiated
self.request = kwargs.pop("request")
super(BaseFormSetInvoice, self).__init__(*args, **kwargs)
self.queryset.concept = ConceptDetail.objects.filter(
Q(area__name=self.request.POST.get('area')) | Q(area__name='default')
)
class InvoiceForm(forms.ModelForm):
class Meta:
model = Invoice
fields = ('invoice',)
class InvoiceDetailForm(forms.ModelForm):
class Meta:
model = InvoiceDetail
fields = ('concept',)
InvoiceDetailFormSet = inlineformset_factory(Invoice, InvoiceDetail,
formset=BaseFormSetInvoice,
form=InvoiceDetailForm,
extra=1)
How can i fix it?, what do i need to read to solve this problem, I tried to debug the process, i didn't find answers.
i try to do this:
def FooForm(forms.ModelForm):
def __init__(self, *args, **kwargs):
super(FooForm, self).__init__(*args, **kwargs)
self.fields['concept'].queryset = ConceptDetail.objects.filter(area__name='default')
In a inlineformset_factory how can do it?.
After a lot of tests, my solution is override the formset before to rendering, using get_context_data.
def get_context_data(self, **kwargs):
context = super(CreateInvoiceProcedureView, self).get_context_data(**kwargs)
for form in context['invoice_detail_form']:
form.fields['concept'].queryset = ConceptDetail.objects.filter(area__name=self.request.POST.get('area'))
return context

Dynamic Form fields in `__init__` in Django admin

I want to be able to add fields to django admin form at runtime. My model and form:
#admin.py
class SitesForm(forms.ModelForm):
def __init__(self, *args, **kwargs):
super(SitesForm, self).__init__(*args, **kwargs)
self.fields['mynewfield'] = forms.CharField()
class SitesAdmin(admin.ModelAdmin):
form = SitesForm
admin.site.register(Sites,SitesAdmin)
#model.py
class Sites(models.Model):
url = models.URLField(u'URL')
is_active = models.BooleanField(default=True, blank=True)
is_new = models.BooleanField(default=False, blank=True)
group = models.ForeignKey('SitesGroup')
config = models.TextField(blank=True)
Field mynewfield isn't displayed in form. Why?
You shouldn't be adding a new field to your form in that way, you can just do it as you would any other field and the form will contain both the Model's original fields and your new fields:
class SitesForm(forms.ModelForm):
mynewfield = forms.CharField(max_length=255, blank=True)
class Meta:
model = Sites
class SitesAdmin(admin.ModelAdmin):
form = SitesForm
admin.site.register(Sites, SitesAdmin)
Edit: Sorry, should have read what you had written a little better. If you want a dynamic field like that, then you need to do the following and it will do exactly what you want:
class SitesForm(forms.ModelForm):
class Meta:
model = Sites
def __init__(self, *args, **kwargs):
self.base_fields['mynewfield'] = forms.CharField(max_length=255, blank=True)
super(SitesForm, self).__init__(*args, **kwargs)
class SitesAdmin(admin.ModelAdmin):
form = SitesForm
admin.site.register(Sites, SitesAdmin)
It's the base_fields that gets composed by the metaclass that holds the fields that the form will use.
Solution:
class AdminForm(forms.ModelForm):
def __init__(self, *args, **kwargs):
super(AdminForm, self).__init__(*args, **kwargs)
self.fields.insert(1, 'myfield', forms.CharField())
class MyAdmin(admin.ModelAdmin):
form = AdminForm
def get_fieldsets(self, request, obj=None):
return (
(None, {
'fields': (..., 'myfield',),
}),
)