Allows for an internal link markup to be saved inside markdown-formatted Textfield entries. The links can be used alone, or inside a markdown-formatted link:
{{film:alien-1979}}
{{person:douglas-trumbull}}
[The first Alien movie]({{film:alien-1979}})
...will become (at least on my website), respectively:
[*Alien* (1979)](/cinedex/film/alien-1979)
[Douglas Trumbull](/cinedex/person/douglas-trumbull)
[The first Alien movie](/cinedex/film/alien-1979)
Using the filter, the link is only looked up at display time, so if your view's URL has changed, that should automatically update with the reverse() lookup.
You could tweak the regex pattern to match whatever link markup you prefer. I also use Markdown to process my description fields, so I make the link return a markdown-formatted link instead of HTML, but you could tweak that too. If you use Markdown, you'd want to put this filter first.
So to display a description TextField with internal links, in the template would be something like this:
{{ entity.description|internal_links|markdown }}
(See the Django docs on writing your own custom filters for more details on writing and registering filters.)
Written for my movie podcast website, The Optical, and a basic version was shared as the answer to this Stack Overflow question.