django how to create instance of user - django

Question

I am creating a simple application, successfully created for a single user, but I want to develop for multiple users, but unable to do so... i.e. user A can create his task and save in the database. similar B user can create tasks and store in the database. and each can see their own tasks I am newbie unable to proceed with the creation of instance can someone please guide me or point me to a blog ( searched online but no help ) I already asked this question however i was not clear ( django each user needs to create and view data Issue) hope now I am clear.
My model :
from django.contrib.auth.models import User, AbstractUser
from django.db import models
# Create your models here.
from django.db.models import Sum, Avg
class Task(models.Model):
user = models.ForeignKey(User, null=True,on_delete=models.CASCADE)
title = models.CharField(max_length=200)
complete = models.BooleanField(default=False)
created = models.DateTimeField(auto_now_add=True,auto_now=False,blank=True)
purchase_date = models.DateField(auto_now_add=False,auto_now=False,blank=True,null=True)
price = models.FloatField(max_length=5,default='0.00',editable=True)
def __str__(self):
return self.title
#classmethod
def get_price_total(cls):
total = cls.objects.aggregate(total=Sum("price"))['total']
print(total)
return total
Views
def createTask(request):
form = TaskForm()
if request.method =='POST':
form=TaskForm(request.POST)
if form.is_valid():
form.save()
return redirect('query')
context = {'form':form}
return render(request,'tasks/create.html',context)
def display(request):
# tasks = Task.objects.all()
tasks = request.user.task_set.all()
form = TaskForm()
if request.method =='POST':
if form.is_valid():
form.save()
return redirect('/')
# tasks= task.objects.all()
print("tasks",Task.get_price_total)
context = {'tasks':tasks,'form':form,'Totalprice':Task.get_price_total}
return render(request,'tasks/products.html',context)
urls
from django.urls import path
from . import views
urlpatterns = [
#path('', views.index, name="list"),
path('', views.query, name="query"),
path('create/', views.createTask, name="create"),
path('update_task/<str:pk>/', views.updateTask, name="update_task"),
path('register/', views.registerPage,name="register"),
path('login/', views.loginPage,name="login"),
path('logout/', views.logoutUser,name="logout"),
path('delete/<str:pk>/', views.deleteTask, name="delete"),
path('query/', views.query, name="query"),
path('products/', views.display, name="products"),
path('search/', views.showresults, name="search"),
]
Error (output)
Internal Server Error: /products/
Traceback (most recent call last):
File "C:\Users\s5114509\AppData\Local\Programs\Python\Python38\lib\site-packages\django\core\handlers\exception.py", line 34, in inner
response = get_response(request)
File "C:\Users\s5114509\AppData\Local\Programs\Python\Python38\lib\site-packages\django\core\handlers\base.py", line 124, in _get_response
raise ValueError(
ValueError: The view tasks.views.display didn't return an HttpResponse object. It returned None instead.
[21/Oct/2020 14:35:59] "GET /products/ HTTP/1.1" 500 60680

Answer 1

From what I heard it sounds lke you want to save a task when a user creates one. You don't want to include the user field in the form. You have to first get the model instance returned by the TaskForm.save() method. Now you have to assign the user field to the request.user since the user is authenticated. Here is how you can achieve that.
def createTask(request):
form = TaskForm()
task = None
if request.method =='POST':
form=TaskForm(request.POST)
if form.is_valid():
#Just get the Task instance do not make any commitments to database
task = form.save(commit=False)
#Now update the user
task.user = request.user
#Finally save to database
task.save()
return redirect('query')
context = {'form':form}
return render(request,'tasks/create.html',context)
On display you are getting an error because you are return a response only when a POST request is made. Check you identation and correct it. Identation mean scope in python. Check I have modified you code
def display(request):
#tasks = Task.objects.all()
tasks = request.user.task_set.all()
form = TaskForm()
if request.method =='POST':
if form.is_valid():
form.save()
return redirect('/')
#tasks= task.objects.all()
print("tasks",Task.get_price_total)
context = {'tasks':tasks,'form':form,'Totalprice':Task.get_price_total}
return render(request,'tasks/products.html',context)
Take a look at python identation