Double users created - django

Question

I have an issue with my code in the sense that when a student registers, a double instance of the student is created. I don't know what's the problem with these block of code. Please help out,also I don't know how to make a link between a teacher and a student so as to allow the teacher to add results for students.
views.py
from django.shortcuts import render, redirect
from django.contrib import messages
from django.contrib.auth.decorators import login_required
from .forms import UserRegisterForm,UserUpdateForm ,InformationUpdateForm,InformationForm
def home(request):
return render(request, 'student/home.html')
def register(request):
if request.method == 'POST':
form = UserRegisterForm(request.POST)
a_form=InformationForm(request.POST)
# ####and a_form.is_valid()
if form.is_valid() and a_form.is_valid():
user = form.save()
# form.save()
#finally this get links the models, forms and views for user input and all information is registered
information = a_form.save()
# a_form.save()
user.information.majors=a_form.cleaned_data.get('majors')
user.information.department=a_form.cleaned_data.get('department')
user.information.nationality=a_form.cleaned_data.get('nationality')
user.information.date_of_birth=a_form.cleaned_data.get('date_of_birth')
user.information.passport_number=a_form.cleaned_data.get('passport_number')
user.information.phone_number=a_form.cleaned_data.get('phone_number')
user.information.sex=a_form.cleaned_data.get('sex')
user.save()
information.save()
# for this type user input is for for username,last,first and email is registered
# form.save()
username = form.cleaned_data.get('username')
messages.success(request, f'Your account has been created! You are now able to log in')
return redirect('login')
else:
form = UserRegisterForm()
a_form = InformationForm()
context={'form':form,'a_form':a_form }#,'a_form':a_form
return render(request, 'student/register.html', context)
#login_required
def profile(request):
return render(request, 'student/profile.html')#,context
#login_required
def profile_update(request):
if request.method == 'POST':
u_form=UserUpdateForm(request.POST,instance=request.user)
i_form=InformationUpdateForm(request.POST,request.FILES,instance=request.user.information)
if u_form.is_valid() and i_form.is_valid():
u_form.save()
i_form.save()
messages.success(request, f'Your account has been updated!')
return redirect('profile')
else:
u_form=UserUpdateForm(instance=request.user)
i_form=InformationUpdateForm(instance=request.user.information)
context={'u_form': u_form,
'i_form':i_form}
return render(request, 'student/profile_update.html',context)
models.py
from django.db import models
from django.contrib.auth.models import User
from PIL import Image
# CHOICES=[('M','Male'),
# ('F','Female')]
class Information(models.Model):
M='Male'
F='Female'
SELECT_GENDER_CHOICE=[(M, 'Male'),
(F, 'Female')]
########################################################
B='Bachelors'
Ma='Masters'
P='PhD'
SELECT_DEGREE_CHOICE=[(B, 'Bachelors'),
(Ma, 'Masters'),(P, 'PhD')]
#########################################################
Y1='1 year'
Y2='2 year'
Y3='3 year'
Y4='4 year'
Y5='5 year'
SELECT_YEARS_CHOICE=[(Y1, '1 year'),(Y2, '2 year'),(Y3, '3 year'),(Y4, '4 year'),(Y5, '5 year')]
user = models.OneToOneField(User,null=True,on_delete=models.CASCADE)
image = models.ImageField(default='default.jpg', upload_to='student')
nationality=models.CharField(max_length=120,blank=False)
sex=models.CharField(max_length=8,choices=SELECT_GENDER_CHOICE,default=M)
department=models.CharField(max_length=120,blank=False)
years=models.CharField(max_length=120,blank=False,choices=SELECT_YEARS_CHOICE,default=Y1,null=True)
degree=models.CharField(max_length=120,blank=False,choices=SELECT_DEGREE_CHOICE,null=True)
majors=models.CharField(max_length=500,blank=False)
phone_number=models.CharField(max_length=12,blank=False)
passport_number=models.CharField(max_length=50,blank=False)#unique=True)
date_of_birth=models.CharField(max_length=10,blank=False)
report=models.FileField(default='StudentResults/DEFAULT_SHEET.xlsx',upload_to='StudentResults',max_length=500,blank=True)#,null=True
reg_no=models.CharField(max_length=10,null=True,unique=True)
def __str__(self):
return f'{self.passport_number} Information'
def save(self,*args, **kwargs):
super().save(*args, **kwargs)
img=Image.open(self.image.path)
if img.height>300 or img.width>300:
output_size=(300,300)
img.thumbnail(output_size)
img.save(self.image.path)
forms.py
from django import forms
from django.contrib.auth.models import User
from django.contrib.auth.forms import UserCreationForm
from .models import Information
# CHOICES=[('M','Male'),
# ('F','Female')]
class UserRegisterForm(UserCreationForm):
email = forms.EmailField(widget=forms.TextInput(attrs={'placeholder': 'Email'}))
username = forms.CharField(widget=forms.TextInput(attrs={'placeholder': 'Username'}))
first_name = forms.CharField(widget=forms.TextInput(attrs={'placeholder': 'First name'}))
last_name = forms.CharField(widget=forms.TextInput(attrs={'placeholder': 'Last name'}))
password1 = forms.CharField(widget=forms.PasswordInput(attrs={'placeholder': 'Password'}))
password2 = forms.CharField(widget=forms.PasswordInput(attrs={'placeholder': 'Confirm'}))
class Meta:
model = User
fields = ['username','first_name','last_name', 'email', 'password1', 'password2']
class InformationForm(forms.ModelForm):
#sex=forms.ChoiceField(choices=CHOICES)
department = forms.CharField(widget=forms.TextInput(attrs={'placeholder': 'Department'}))
majors = forms.CharField(widget=forms.TextInput(attrs={'placeholder': 'Majors'}))
nationality = forms.CharField(widget=forms.TextInput(attrs={'placeholder': 'Nationality'}))
date_of_birth = forms.CharField(widget=forms.TextInput(attrs={'placeholder': 'Date of birth'}))
passport_number = forms.CharField(widget=forms.TextInput(attrs={'placeholder': 'Passport number'}))
phone_number = forms.CharField(widget=forms.TextInput(attrs={'placeholder': 'Phone number'}))
class Meta:
model=Information
fields=['department','majors','degree','years','nationality','date_of_birth','passport_number','phone_number','sex']
class UserUpdateForm(forms.ModelForm):
email = forms.EmailField()
class Meta:
model = User
fields = ['email']
# def email(self):
# email = self.cleaned_data.get("email")#this gets the default title but does not override the required field
# #you can have multiple nested if else/elif statements. You can use this for email validation
# if not ".com" in email:
# raise forms.ValidationError("This is not a email")
# else:
# return email
class InformationUpdateForm(forms.ModelForm):
class Meta:
model=Information
fields=['phone_number']
signals.py
from django.db.models.signals import post_save
from django.contrib.auth.models import User
from django.dispatch import receiver
from .models import Information
#receiver(post_save,sender=User)
def create_information(sender,instance,created,**kwargs):
if created:
Information.objects.create(user=instance)
#receiver(post_save,sender=User)
def save_information(sender,instance,**kwargs):
instance.information.save()
student-profile-page
{% extends "student/base.html" %}
{% load crispy_forms_tags %}
{% block content %}
<div class="content-section">
<div class="media">
<img class="rounded-circle account-img" src="{{ user.information.image.url }}">
<div class="media-body">
<p class="text-secondary">Username: {{ user.username }}</p>
<p class="text-secondary">First Name: {{ user.first_name }}</p>
<p class="text-secondary">Last Name: {{ user.last_name }}</p>
<p class="text-secondary">Email: {{ user.email }}</p>
<p class="text-secondary">Passport Number: {{ user.information.passport_number }}</p>
<p class="text-secondary">Date of Birth: {{ user.information.date_of_birth }}</p>
<p class="text-secondary">Sex: {{ user.information.sex }}</p>
<p class="text-secondary">Phone Number: {{ user.information.phone_number }}</p>
<p class="text-secondary">Nationality: {{ user.information.nationality }}</p>
<p class="text-secondary">Majors: {{ user.information.majors }}</p>
<p class="text-secondary">Depatrment: {{ user.information.department }}</p>
<p class="text-secondary">Results: {{ user.information.result }}</p>
<p class="text-secondary">Years: {{ user.information.years }}</p>
<p class="text-secondary">Degree: {{ user.information.degree }}</p>
<a class="btn btn-outline-info" href="{{ user.information.report.url}}">Download your Report</a>
</div>
</div>
{% comment %} <form method="POST">
{% csrf_token %}
<fieldset class="form-group" enctype="multipart/form-data">
<legend class="border-bottom mb-4">Profile Info</legend>
{{ i_form|crispy }}
{{ u_form|crispy }}
</fieldset>
<div class="form-group">
<button class="btn btn-outline-info" type="submit">Update</button>
</div>
</form>
</div> {% endcomment %}
{% endblock content %}

Answer 1

That is because you are saving a_form.save() then again saving user.information.save(). You need to change the code like this:
user = form.save()
information = a_form.save(commit=False)
information.user = user
information.save()
messages.success(request, 'Your account has been created! You are now able to log in')
return redirect('login')
You can remove the rest of the code regarding user.information and remove the signals as well. You do not need signals to create Information instance because you have forms to do that.

Answer 2

You are getting double instance of user because of create_information signal.
user = form.save() in following code will save a User instance.
def register(request):
if request.method == 'POST':
form = UserRegisterForm(request.POST)
a_form =InformationForm(request.POST)
if form.is_valid() and a_form.is_valid():
# form.save() creates a user, and triggers create_information signal
user = form.save()
information = a_form.save()
Now, you have a signal create_information, which is triggered after a User instance is saved (this signal is a post_save singal).
Your user = form.save() will create a user, and will triggers create_information signal.
#receiver(post_save,sender=User)
def create_information(sender,instance,created,**kwargs):
if created:
Information.objects.create(user=instance)
This save another instance of Information, and since Information model has OneToOne mapping to User, another User instance is also saved.
Side note: You have three Information instances saved as well. One created by create_information signal, one by save_information signal, and third by a_form.save() method. This number can be more if cyclic signals are triggered, but not sure about that, so you'll have to check that by yourself.
Solution:
Firstly, get rid of all singals.
Secondly, add User to Information instance before saving it.
def register(request):
if request.method == 'POST':
form = UserRegisterForm(request.POST)
a_form =InformationForm(request.POST)
if form.is_valid() and a_form.is_valid():
user = form.save()
information = a_form.save(commit=False)
information.user = user
information.save()