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Django create parent model and child model in one form

I am learning Python and Django, and I am trying to create a recipe with a form. The problem is I have two models, Recipe and RecipeIngredient and I don't know how to add recipe ingredients to the form since it requires the primary key of the recipe and from what I understand, the key is not created until after the form is saved? So how can I create a recipe with both the Recipe and RecipeIngredient when Recipe is not yet initialized?
Models.py:
class Recipe(models.Model):
user = models.ForeignKey(settings.AUTH_USER_MODEL, on_delete=models.CASCADE)
image = models.ImageField(upload_to='image/', blank=True, null=True)
name = models.CharField(max_length=220) # Lasanga
description = models.TextField(blank=True, null=True)
notes = models.TextField(blank=True, null=True)
cookTime = models.CharField(max_length=50, blank=True, null=True)
timeStamp = models.DateTimeField(auto_now_add=True)
updated = models.DateTimeField(auto_now=True)
active = models.BooleanField(default=True)
#property
def title(self):
return self.name
def get_absolute_url(self):
return reverse("recipes:detail", kwargs={"id": self.id}) # recipes is from url.py app_name
def get_hx_url(self):
return reverse("recipes:hx-detail", kwargs={"id": self.id}) # recipes is from url.py app_name
def get_edit_url(self):
return reverse("recipes:update", kwargs={"id": self.id})
def get_image_upload_url(self):
return reverse("recipes:recipe-ingredient-image-upload", kwargs={"parent_id": self.id})
def get_delete_url(self):
return reverse("recipes:delete", kwargs={"id": self.id})
def get_ingredients_children(self):
return self.recipeingredient_set.all()
def get_instruction_children(self):
return self.recipeinstruction_set.all()
class RecipeIngredient(models.Model):
recipe = models.ForeignKey(Recipe, on_delete=models.CASCADE)
name = models.CharField(max_length=220) # grilled chicken pasta
description = models.TextField(blank=True, null=True)
quantity = models.CharField(max_length=50, blank=True, null=True)
unit = models.CharField(max_length=50, validators=[validate_unit_of_measure], blank=True, null=True)
instructions = models.TextField(blank=True, null=True)
timeStamp = models.DateTimeField(auto_now_add=True)
updated = models.DateTimeField(auto_now=True)
active = models.BooleanField(default=True)
def get_absolute_url(self):
return self.recipe.get_absolute_url() # recipe cannot be none
def get_hx_edit_url(self):
kwargs = {
"parent_id": self.recipe.id,
"id": self.id
}
return reverse("recipes:hx-ingredient-detail", kwargs=kwargs)
def get_delete_url(self):
kwargs = {
"parent_id": self.recipe.id,
"id": self.id
}
return reverse("recipes:ingredient-delete", kwargs=kwargs)
Views.py
#login_required
def recipe_create_view(request):
form = RecipeForm(request.POST or None)
context = {
"form": form,
}
if form.is_valid():
obj = form.save(commit=False)
obj.user = request.user
obj.save()
if request.htmx: # necessary to pass headers from htmx response if we want the django to recognise the htmx change
headers = {
"HX-Redirect": obj.get_absolute_url()
}
return HttpResponse("Created", headers=headers)
# if request.htmx: # could use this but the url doesn't update, stays as create, would need to use HX-Push header & HttpResponse + context somehow
# context = {
# "object": obj
# }
# return render(request, "recipes/partials/detail.html", context)
return redirect(obj.get_absolute_url())
return render(request, "recipes/create.html", context)
#login_required
def recipe_ingredient_update_hx_view(request, parent_id=None, id=None): # this is both create & edit, can create
if not request.htmx:
raise Http404
try:
parent_obj = Recipe.objects.get(id=parent_id, user=request.user)
except:
parent_obj = None
if parent_obj is None:
return HttpResponse("Not Found.")
instance = None
if id is not None:
try:
instance = RecipeIngredient.objects.get(recipe=parent_obj, id=id) # think of this as an object if that helps
except:
instance = None
form = RecipeIngredientForm(request.POST or None, instance=instance)
url = reverse("recipes:hx-ingredient-create", kwargs={"parent_id": parent_obj.id})
if instance:
url = instance.get_hx_edit_url()
context = {
"url": url,
"form": form,
"object": instance
}
if form.is_valid():
new_obj = form.save(commit=False)
if instance is None:
new_obj.recipe = parent_obj
new_obj.save()
context['object'] = new_obj # because it's possible the object/instance in None
return render(request, "recipes/partials/ingredient-inline.html", context)
return render(request, "recipes/partials/ingredient-form.html", context)
forms.py
from django import forms
from .models import Recipe, RecipeIngredient
class RecipeForm(forms.ModelForm):
class Meta:
model = Recipe
fields = ['name', 'image', 'description', 'notes', 'cookTime']
def __init__(self, *args, **kwargs):
super().__init__(*args, **kwargs)
for field in self.fields:
new_data = {
"placeholder": f"Recipe {str(field)}",
"class": "form-control",
}
self.fields[str(field)].widget.attrs.update(new_data)
class RecipeIngredientForm(forms.ModelForm):
class Meta:
model = RecipeIngredient
fields = ['name', 'quantity', 'unit']
urls.py
from django.urls import path
from .views import (
recipe_list_view,
recipe_delete_view,
recipe_create_view,
recipe_update_view,
recipe_detail_hx_view,
recipe_ingredient_update_hx_view,
recipe_ingredient_delete_view,
recipe_ingredient_image_upload_view,
recipe_ingredient_url_scrape_view
)
app_name='recipes' # allows use of recipes:list as a reverse url call
urlpatterns = [
path('', recipe_list_view, name='list'), # index / home / root
path('create/>', recipe_create_view, name='create'),
path('hx/<int:parent_id>/ingredient/<int:id>', recipe_ingredient_update_hx_view, name='hx-ingredient-detail'), #or detail
path('hx/<int:parent_id>/ingredient/', recipe_ingredient_update_hx_view, name='hx-ingredient-create'),
]
create.html
{% extends "base.html" %}
{% load crispy_forms_tags %}
{% load static %}
{% block content %}
<div class="container-fluid px-5">
<h1 class="pb-5">Create Recipe</h1>
<div id="recipe-container">
<form action='.' method="POST" hx-post='.'>
{% csrf_token %}
<div class='row'>
<div class="row d-flex pb-5">
<div class="col-12 col-lg-6 justify-content-center d-flex order-first order-lg-last pictureBox"
style="height: 400px; width:450; border: solid tomato 1px;">
<div class="align-self-center">
{{ form.image|as_crispy_field }}
</div>
</div>
<div class="col-12 col-lg-6 order-lg-first">
<div class="pb-3">{{ form.name|as_crispy_field }}</div>
<div class="pb-3">{{ form.description|as_crispy_field }}</div>
</div>
</div>
<div class="col-12 col-md-6">
{{ form.notes|as_crispy_field }}
</div>
<div class="col-12 col-md-6">
{{ form.cookTime |as_crispy_field }}
</div>
</div>
</div>
<div class='col-12 col-md-4'>
<!-- ADD INGREDIENTS ? -->
</div>
<div class="htmx-indicator">Loading...</div>
<div class="d-flex">
<button class="btn btn-success htmx-inverted-indicator" style='margin-top:10px;' type='submit'>Save</button>
<a class="btn btn-danger" href='{% url "recipes:list" %}'>Delete</a>
</div>
{% if message %}
<p>{{ message }}</p>
{% endif %}
</form>
</div>
</div>
{% endblock content %}
ingredient-form.html
<form action='.' method="POST" hx-post='{% if url %} {{ url }} {% else %} . {{% endif %}' hx-swap='outerHTML'>
{% csrf_token %}
{{ form.as_p}}
<div class="htmx-indicator">Loading...</div>
<button class="htmx-inverted-indicator" style='margin-top:10px;' type='submit' >Save</button>
</form>
ingredient-inline.html
<div class="py-1" id="ingredient-{{object.id}}">
<p>{% if not edit %} <b>{{ object.quantity }} {% if object.unit %} {{ object.unit }} {% endif %}</b> {% else %} {{ object.quantity }} {{ object.unit }} {% endif %} - {{ object.name }}</p>
{% if edit %}
<button class="btn btn-primary" hx-trigger='click' hx-get='{{ object.get_hx_edit_url }}' hx-target="#ingredient-{{object.id}}">Edit</button> <!-- target will replace whole div-->
<button class="btn btn-danger" href='{{ object.get_delete_url }}' hx-post='{{ object.get_delete_url }}' hx-confirm="Are you sure you want to delete {{ object.name }}?" hx-trigger='click' hx-target="#ingredient-{{object.id}}" hx-swap="outerHTML">Delete</button>
{% endif %}
</div>

The key to this problem is using a formset, as you will likely want to save multiple ingredients to the recipe. Django documentation outlines how to use them. Your view would end up looking something like below, allowing you to save the parent model, which will give you the parent instance/primary key to then save the ingredients.
def recipe_create_view(request):
form = RecipeForm(request.POST or None)
RecipeIngredientFormset = formset_factory(RecipeIngredientForm)
formset = RecipeIngredientFormset(request.POST or None)
context = {
"form": form,
"formset": formset,
}
if request.method == "POST":
if form.is_valid() and formset.is_valid():
parent = form.save(commit=False)
parent.user = request.user
parent.save()
#recipe ingredients
for form in formset:
child = form.save(commit=False)
child.recipe = parent
child.save()

how to display all the reviews for the particular product?

With the below code i am adding reviews for some particular product in the database and it is doing good but the problem is while displaying the reviews for the selected product.I get confused how can i display the all reviews of some product and which review done by which user at what time?
models.py
class Product(models.Model):
name = models.CharField(max_length=250)
description = models.TextField(blank=True)
featured = models.BooleanField(default=False)
def __str__(self):
return self.name
class Review(models.Model):
product = models.ForeignKey(Product, on_delete=models.CASCADE)
user = models.ForeignKey(User, on_delete=models.CASCADE)
review = models.TextField()
date = models.DateTimeField(auto_now_add=True)
def __str__(self):
return self.review
views.py
def detail(request,pk):
product = College.objects.get(pk=pk)
form = ReviewForm()
return render(request,'products/detail.html',{'product':product,'form':form})
#login_required(login_url='products:signin')
def review(request,pk):
if request.method == "POST":
form = ReviewForm(request.POST)
if form.is_valid():
review = form.save(commit=False)
review.product = Product.objects.get(pk=pk)
review.user = request.user
review.save()
messages.success(request, "Review saved")
return redirect('products:detail',pk)
else:
messages.error(request,'error in form')
return redirect('products:detail', pk)
detail.html
<h3>All reviews(total.no. of reviews?)</h3>
# Here i want to display all reviews and which is done by which user and at what time
<div class="col-lg-6 col-md-6 mb-6">
<form method="post" action="{% url 'products:review' product.pk %}">
{% csrf_token %}
{% form.as_p %}
<input type="submit" class="btn btn-success">
</form>
</div>

You can do it like this using reverse relation:
<h3>All reviews {{ product.review_set.count }}</h3>
{% for review in product.review_set.all %}
{{ review.review }}
{{ review.date }}
{% endfor %}

The view students.views.addgrregister didn't return an HttpResponse object. It returned None instead

ValueError at /students/addgrregister/
i am trying to add students in gr_register but its giving an error due to this error the code is not working i also upload the template (addgrregister.html) kndly tell me where is the issue in these pages
models.py
class gr_register(models.Model):
Gender_Choices = (
('M', 'Male'),
('FM', 'Female'),
)
Status_Choices = (
('P', 'Present'),
('FM', 'Left'),
)
gr_no = models.IntegerField(primary_key=True)
first_name = models.CharField(max_length=20)
last_name = models.CharField(max_length=20)
date_birth = models.DateField(null=True)
classes_A = models.ForeignKey(Classes, on_delete=models.CASCADE, related_name="classes_A", default=1, verbose_name="Class of Admission")
sections_A = models.ForeignKey(Sections, on_delete=models.CASCADE, related_name="sections_A", default=1, verbose_name="Section of Admission")
gender = models.CharField(max_length=10, choices=Gender_Choices)
classes_C = models.ForeignKey(Classes, on_delete=models.CASCADE, related_name="classes_C", verbose_name="Current Class")
sections_C = models.ForeignKey(Sections, on_delete=models.CASCADE, related_name="sections_C", verbose_name="Current Section")
address = models.CharField(max_length=100, null=True, verbose_name="Home Address")
area_code = models.ForeignKey(Area, on_delete=models.CASCADE, verbose_name="Area")
status = models.CharField(max_length=10, choices=Status_Choices, default='P')
class Meta:
ordering = ('gr_no',)
def __str__(self):
return self.first_name
views.py
from django.shortcuts import get_object_or_404, render, redirect
def addgrregister(request):
if request.method == 'POST':
form = gr_registerForm(request.POST)
if form.is_valid():
form.save()
return redirect('home')
else:
form = gr_registerForm()
return render(request, 'students/addgrregister.html', {'form': form})
forms.py
from django import forms
from django.forms import ModelChoiceField, ModelForm
from .models import *
class gr_registerForm(ModelForm):
classes_A = forms.ModelChoiceField(queryset=Classes.objects.all())
sections_A = forms.ModelChoiceField(queryset=Sections.objects.all())
classes_C = forms.ModelChoiceField(queryset=Classes.objects.all())
sections_C = forms.ModelChoiceField(queryset=Sections.objects.all())
area_code = forms.ModelChoiceField(queryset=Area.objects.all())
class Meta:
model = gr_register
fields = '__all__'
def init(self, *args, **kwargs):
forms.ModelForm.init(self, *args, **kwargs)
addgrregister.html
{% extends 'authenticate/base.html' %}
{% block content %}
<div class="container">
<h4 class="text-center">ADD GR_REGISTER</h4>
<hr/>
<form method="POST" action="{% url 'addgrregister' %}" enctype="multipart/form-data">
{% csrf_token %}
{% for field in form %}
<div class="form-group row">
<label for="id_{{ field.name }}" class="col-2 col-form-label">{{ field.label }}</label>
<div class="col-10">
{{ field }}
</div>
</div>
{% endfor %}
<button type="submit" class="btn btn-primary" name="button">Add GR_REGISTER</button>
</form>
<br/><br/>
</div>
{% endblock %}

There is nothing returned when form is not valid. I think you try like this:
def addgrregister(request):
form = gr_registerForm(request.POST or None) # it initates a form. If the request type is POST, then there will be a dict available with posted data in request.POST. If request is not POST, then the form will initiate with empty data.
if request.method == 'POST':
if form.is_valid(): # Form valid checks if the submitted form is valid or not. If not, it will store errors in the form. When that form is passed to template, it will show errors in html
form.save() # It will store data in DB
return redirect('home')
# when for is invalid, it will show the error in the form
return render(request, 'students/addgrregister.html', {'form': form})
Update
Show form errors in template:
{% for field in form %}
<div class="form-group row">
<label for="id_{{ field.name }}" class="col-2 col-form-label">{{ field.label }}</label>
<div class="col-10">
{{ field }}
{{ field.errors }} // <-- Updated here
</div>
</div>
{% endfor %}

Django: Form is not valid

I am currently struggling to get my form to work properly. I created the form manually (template.html) and I can see all the data when I call it with print(request.POST) (in views.py - checkout) however form.is_valid(): (in views.py - checkout) doesn't work. Means my form is not valid.
I think the issue is, that I created the form manually and combined it with a model form where I want after validating my data with form.valid() save it in. Can anyone of you guys help me with my problem, why it's not valid?
template.html
<form action="{% url 'checkout:reserve_ticket' %}" method="post">
{% csrf_token %}
{% for ticket in event.tickets.all %}
<p>
{{ ticket.name }} for {{ ticket.price_gross }} with quantity:
<input type="hidden" name="order_reference" value="123456af">
<input type="hidden" name="ticket" value="{{ ticket.id }}">
<input type="hidden" name="ticket_name" value="{{ ticket.name }}">
<input type="number" name="quantity" max="{{ ticket.event.organiser.max_quantity_per_ticket }}" placeholder="0">
</p>
{% endfor %}
<button type="submit" class="btn btn-primary">Continue</button>
</form>
models.py
class ReservedItem(models.Model):
order_reference = models.CharField(
max_length=10,
unique=True
)
ticket = models.ForeignKey(
Ticket,
on_delete=models.PROTECT,
related_name='reserved_tickets'
)
ticket_name = models.CharField(max_length=100)
quantity = models.IntegerField()
created = models.DateTimeField(auto_now_add=True)
updated = models.DateTimeField(auto_now=True)
forms.py
class ReserveForm(forms.ModelForm):
class Meta:
model = ReservedItem
fields = ['order_reference', 'ticket', 'ticket_name', 'quantity']
views.py - events
# Create your views here.
class EventDetailView(DetailView):
context_object_name = 'event'
def get_object(self):
organiser = self.kwargs.get('organiser')
event = self.kwargs.get('event')
queryset = Event.objects.filter(organiser__slug=organiser)
return get_object_or_404(queryset, slug=event)
views.py - checkout
def reserve_ticket(request):
if request.method == 'POST':
form = ReserveForm(request.POST)
if form.is_valid():
print("Hello World")
return redirect("https://test.com")
else:
print("back to homepage")

django model dropdown missing in html view

I'm writing a django app, and I'd like for users to be able to select a [team_number] from a dropdown menu, then when they hit submit be redirected to a page that renders out the database information associated with that selection. I'm using the redirect class View, but the problem I'm having is that there is no dropdown menu showing up to select [team_number] from on the html page team-stats.html.
views.py:
class TeamStatsView(View):
def get(self, request, *args, **kwargs):
return render(request, 'team-stats.html',
{'team_number': TeamStats()})
def post(self, request, *args, **kwargs):
team_number = TeamStats(request.POST, request.FILES)
if team_number.is_valid():
# do stuff & add to database
team_number.save()
team_number = TeamStats.objects.create()
# use my_file.pk or whatever attribute of FileField your id is
# based on
return HttpResponseRedirect('/team-stats/%i/' % team_number.pk)
return render(request, 'team-stats.html', {'team_number': team_number})
models.py:
class Team(models.Model):
team_number = models.IntegerField()
team_notes = models.CharField(max_length=150)
event_id = models.ForeignKey(
'Event', on_delete=models.CASCADE, unique=False)
def __unicode__(self):
return str(self.team_number)
class Meta:
db_table = 'teams'
app_label = 'frcstats'
forms.py:
class TeamStats(forms.ModelForm):
class Meta:
model = Team
fields = ['team_number']
team-stats.html:
<form method="post" action="">
{% csrf_token %} {{ TeamStatsView }}
<input type="submit" value="Submit" />
</form>
If there are any other files that I need to update into here to show what I'm trying to do, please let me know. Thanks

Try changing your view variable name to team_numbers and replacing your team-stats.html snippet with the following:
<form method="post" action="">
<select name="teams">
{% for team_number in team_numbers %}
<option value="{{ team_number }}">Team Num: {{ team_number }}</option>
{% endfor %}
</select>
</form>
Then update your view to:
class TeamStatsView(View):
def get(self, request, *args, **kwargs):
return render(request, 'team-stats.html',
{'team_numbers':Team.objects.values('team_number')})

You can use choices=NUMBERS
NUMBERS = (
('1','1'),
('2','2'),
('3','3'),
('4','4')
)
class Team(models.Model):
team_number = models.IntegerField(choices=NUMBERS )
team_notes = models.CharField(max_length=150)
event_id = models.ForeignKey(
'Event', on_delete=models.CASCADE, unique=False)
def __unicode__(self):
return str(self.team_number)
class Meta:
db_table = 'teams'
app_label = 'frcstats'

Your view variable is called team_number.
Try to change TeamStatsView into team_number:
<form method="post" action="">
{% csrf_token %} {{ team_number }}
<input type="submit" value="Submit" />
</form>