redirect with primary key django {% url %}

Question

I want make blog where I have categories and posts inside. Categories should be displayed, and when you click on it, you are redirected to another site where articles of this category are shown.

models.py:

class Category(CMSPlugin):
    title = models.CharField(max_length=20, default='category')

    def __unicode__(self):
        return self.title


class Blog_post(CMSPlugin):
    category = models.ForeignKey(Category)
    style = models.ForeignKey(Blog_style)
    title = models.CharField(max_length=200, default='title')
    description = models.CharField(max_length=200,default='description')
    image = models.ImageField(upload_to='static', null=True, blank=True)
    text = models.TextField()
    created_date = models.DateTimeField(default=timezone.now)
    published_date = models.DateTimeField(blank=True, null=True)

    def publish(self):
        self.published_date = timezone.now()
        self.save()

    def __unicode__(self):
        return self.title

views.py

def Blog_list(request):
    posts = Blog_post.objects.filter(published_date__lte=timezone.now()).order_by('published_date')
    category = Category.objects.all()
    return render(request, 'blogspot.html', {'posts': posts, 'category':category})

def post_detail(request, pk):
    post = get_object_or_404(Blog_post, pk=pk)
    return render(request, 'post_detail.html', {'post': post})

def category_detail(request, pk):
    cat = get_object_or_404(Category, id=pk)
    post_with_category = Blog_post.objects.filter(category=cat)
    return render(request, 'articles.html', {'post_with_category': post_with_category})

blogspot.html

{% for post in posts %}
    <h1><a href="{% url 'post_detail' pk=post.pk %}">{{post.title}}</a></h1>
     <a href="{% url 'category_detail' pk=post.category.id %}" >{{ post.category }}</a>
    {{post.title}}
    {{ post.description }}
    {{ post.image }}
    {{ post.text }}{{ post.published_date }}
{% endfor %}

So far works all ok. I can click on {{post.title}} and im redirected to post_detail. Now i want to make same logic with categories. When i click on {{post.category}} i want redirect to articles.html where u can see all articles in specific category.

EDIT:

I inserted code to show posts in categories. I stucked with for loop. If i use loop mentioned in post, I get all posts and categories. The problem is if i have 2 posts in one category and this loop will show 2x "category" in template.

So I edited my for loop.

{% for post in category %}
        {{post.title}}
        {% endfor %}

If I insert <a href="{% url 'category_detail' pk=post.category.id %}" >{{post.title}} in this loop i get no reverse match. I tried to modify views.py category_detail

And url should looks like localhost/<category>/ And another question is, what is QRM alternative comand for "select*from Table Where Column_id= id ;

urls.py

 url(r'^blog/$', views.Blog_list, name='Blog_list'),
    url(r'^blog/(?P<pk>\d+)/$', views.post_detail, name='post_detail'),

Answer 1

If I understand your question, django allows you to reference FK objects through the main object. So, since your post.category is an instance of your Category model, you should be able to use post.category.id to do a reverse lookup, so your template would have something along the lines of:

<a href="{% url 'category_detail' pk=post.category.id %}" >{{ post.category }}</a>

Then, in your category_detail view you would just use the pk to get the lookup:

cat = get_object_or_404(Category, id=pk)
post_with_category = Blog_post.objects.filter(category=cat)

Then you could display the list of posts on the new url link that have the same category, via your new post_with_category object list.

EDIT:

Your urls would want to include something like the following for the above html href tag to work:

url(r'^cat/(?P<pk>[0-9]+)/$', views.category_detail, name='category_detail'),