Django: How to filter and display categories for author in post-CodePudding

Django: How to filter and display categories for author in post I guess there's something wrong with the get_queryset Category.objects.filter(post_author=username)

class Post(models.Model):
    exercisename = models.ForeignKey('Category', on_delete=models.CASCADE)
    hour = models.IntegerField(default=0 )
    min = models.IntegerField(default=0)
    file = models.FileField(null=True,blank=True,upload_to='Files')
    content = models.TextField()
    date_Posted = models.DateTimeField(default=timezone.now)
    author = models.ForeignKey(User, on_delete=models.CASCADE)
        



class Category(models.Model):
    name = models.CharField(max_length=100)
    description = models.TextField()
    image = models.ImageField(upload_to='images/') 


def userpost(request, username):
    
    context = { 
        'Category': Category.objects.filter(post_author=username),
    }
    return render(request, 'blog/user_Posts.html', context)

CodePudding user response：

first you need to have a relation between Post and Catagory inorder to make the query works!!

class Post(models.Model):
    exercisename = models.ForeignKey('Category', on_delete=models.CASCADE)
    hour = models.IntegerField(default=0 )
    min = models.IntegerField(default=0)
    file = models.FileField(null=True,blank=True,upload_to='Files')
    content = models.TextField()
    date_Posted = models.DateTimeField(default=timezone.now)
    author = models.ForeignKey(User, on_delete=models.CASCADE)
    category = models.ForeignKey('Category', on_delete=models.CASCADE)
        



class Category(models.Model):
    name = models.CharField(max_length=100)
    description = models.TextField()
    image = models.ImageField(upload_to='images/') 


def userpost(request, username):

    #this gives the username's posts and change the django query result to a python list
    # a list of catagories
    author_posts_catagories = Post.objects.filter(author=username).values_list('category',flat=True)
    
    context = { 
        # this gives you the selected user catagories from post
        'Category':Category.objects.filter(id__in = author_posts_catagories ) ,
    }
    return render(request, 'blog/user_Posts.html', context)

CodePudding user response：

You should filter your category like this:

Category.objects.filter(post_author__username=username)

When you call ForeignKey directly, it expects object, not field. So you use __{field_name} to call exact field in Django ORM.

Also, your category has no relation to Post model, or has Author relation at all...