How to get the current logged in user? Django models

Question

I want to get the current logged in user to this CreateForm form. Below Im giving my current code, here request.user is not giving me error

ValueError at /create-post/ Cannot assign "<SimpleLazyObject: <User: testuser>>": "Post.author" must be a "Author" instance.

models.py

class Author(models.Model):
   user = models.OneToOneField(User, on_delete=models.CASCADE)
   rate = models.IntegerField(default=0)
 
class Post(models.Model):
    title = models.CharField(max_length= 50)
    overview = models.TextField()
    body_text = RichTextUploadingField(null = True)
    time_upload = models.DateTimeField(auto_now_add=True)
    author = models.ForeignKey(Author, related_name='author', on_delete=models.CASCADE)
    thumbnail = models.ImageField(upload_to = 'thumbnails')
    publish = models.BooleanField()
    categories = models.ManyToManyField(Categories)
    read = models.IntegerField(default=0)
    slug = models.SlugField(null= True, blank= True)

Forms.py

class CreateForm(ModelForm):
class Meta:
    model = Post
    fields = [
        'title',
        'overview',
        'body_text',
        'thumbnail',
        'categories',
        'publish',
    ]

Views.py

def create_post(request):
if request.method == 'POST':
    form = CreateForm(request.POST, request.FILES)
    if form.is_valid:
        post = form.save(commit=False)
        post.author= request.user
        post.save()
        return render(request, 'index.html')
else:
    form = CreateForm()
return render(request, 'create_post.html', {'form': form})

Reuqest author is not author instance, you should do request.user.author — PTomasz, Apr 05 '22 at 10:34

score 2 · Accepted Answer · answered Apr 05 '22 at 10:38

As the error says, post.author expects an Author object, not the user. You thus retrieve this with:

from django.contrib.auth.decorators import login_required

@login_required
def create_post(request):
    if request.method == 'POST':
        form = CreateForm(request.POST, request.FILES)
        if form.is_valid():
            form.instance.author= request.user.author
            form.save()
            return render(request, 'index.html')
    else:
        form = CreateForm()
    return render(request, 'create_post.html', {'form': form})

You should also call the is_valid() method ^[Django-doc], so form.is_valid().

Note: You can limit views to a view to authenticated users with the @login_required decorator ^[Django-doc].

Note: It is normally better to make use of the settings.AUTH_USER_MODEL ^[Django-doc] to refer to the user model, than to use the User model ^[Django-doc] directly. For more information you can see the referencing the User model section of the documentation.

score 2 · Answer 2 · answered Apr 05 '22 at 10:46

2

The author field on your Post model is a foreign key to Author model, and not user. You could replace post.author = request.user with:

if request.user.author:
    post.author = request.user.author
else:
    post.author = Author.objects.create(user=request.user)

The answer from Willem works if an Author instance was already created for the User, but will throw an exception if there's no Author object associated with that user.

answered Apr 05 '22 at 10:46

Kauê Oliveira

134
5

Thank you. I just want get the current logged in user only, I don't want to create a new one. As I will modify this one with login decorators. – Manas S. Roy Apr 05 '22 at 10:52
This snippet is not for creating a new user, it's for creating an author object to associate with that user in case it was not created before – Kauê Oliveira Apr 05 '22 at 10:54
@KauêOliveira: this will likely not work since `request.user.author` will raise an `AttributeError` (`RelatedObjectDoesNotExists`) when there is no related `Author` object. – Willem Van Onsem Apr 05 '22 at 11:07
It won't. It would raise `AttributeError` if we tried to access any attributes on the author, for example `request.user.author.rate`, which is not the case. – Kauê Oliveira Apr 05 '22 at 11:19
2

@KauêOliveira: notice that the `OneToOneField` is *reversed*: hence it will *not* return `None`. There has been a lot of dicussion about this, but `.author` will *not* return `None`. See https://code.djangoproject.com/ticket/3016 and https://stackoverflow.com/questions/33610563/django-onetoone-reverse-relation-doesnotexists-when-empty – Willem Van Onsem Apr 05 '22 at 11:24

How to get the current logged in user? Django models

2 Answers2