Why do I get a No Reverse Match error in this case?

Question

So, this is what's going on:

I am able to get a blog post in my Django 2.1 app by its primary key. However, by demand of the marketing team, I was asked to put a slug on the URL, so instead of /blog/1, I should get /blog/my-blog-post-title.

Thus, while still using the pk value to get the blog post, I just need to get the url to work the way I intend to.

URL:

path('<slug:slug>/', blog_views.blog_single, name='blog-single')

In the HTML, I always refer to this page as:

href="{% url 'blog-single' pk=blogPost.id slug=blogPost.get_slug %}"

, so that I get both the pk and the slug, which is gotten by the get_slug() method declared on the Blog model.

The view is here:

def blog_single(request, pk, slug):

    context = {}
    context['blogPost'] = blogPost.objects.get(id=pk)

    ...

    return render(request, 'blog/blog-single.html', context)

Still, in any page that refers to blog-single in the href, I get the following error:

Reverse for 'blog-single' with keyword arguments '{'pk': 2, 'slug': 'my-blog-post-title'}' not found. 1 pattern(s) tried: ['blog\\/(?P<slug>[-a-zA-Z0-9_]+)\\/$']

I have tried so many different answers I found on the Internet, and read the answer on this post extensively, but I just can't get my head around what's not working: What is a NoReverseMatch error, and how do I fix it?

Any suggestions?

Answer 1

The blog-single url only expects the slug. Do not include the pk kwarg when using the url templatetag.

href="{% url 'blog-single' slug=blogPost.get_slug %}"

Then either change blog_single to:

def blog_single(request, slug):
    context = {'blogPost': blogPost.objects.get(slug=slug)}

Or:

def blog_single(request, pk=None, slug=None):
    ...