How do I access a Post Slug in a Tumblr theme? - tumblr

Question

I want to write a canonical tag into my Tumblr theme, and i need the slug for the (full) url. How can i access the posts-slug within the template? I just have access to the PostId. My current code looks like this:
<link rel="canonical" href="http://domain.com/blog/{block:PostTitle}post/{PostID}{/block:PostTitle}" />
What i want to have is something like this:
<link rel="canonical" href="http://domain.com/blog/{block:PostTitle}post/{PostID}/{PostSlug}{/block:PostTitle}" />
I tried the following tags (which obviously did not work...):
{slug}
{PostSlug}
{Postslug}
What amuses me is, that the API gives out a slug-key on every post, try:
http://(YOU).tumblr.com/api/read?debug=1
Thanks for any hints and suggestions.
Edit: I already scanned http://www.tumblr.com/docs/en/custom_themes for hints - but found nothing useful.

Answer 1

The post slug is not available as a token in Tumblr’s theme DSL. I’m not sure if this is an intentional omission, as post slugs are optional on Tumblr (you can manually set one, but if you don’t your post just goes by its numeric ID). However, you can parse it out of the link inserted by the {Permalink} token, i.e. include it in some hidden element in your template along the lines of
<span class="permalink-url">{Permalink}</span>
(hide the span if you will), then retrieve and parse it with JavaScript:
var plTags = document.querySelectorAll('.permalink-url');
for (i = 0; i <= plTags.length; i++) {
postSlug=plTags[i].replace(/.+\//, '');
// do whatever you want with the slug
}