Flask rewrite url - api

Question

I'm doing a small project that pulls data from tmdb's API.
Right now I have a /tv view that takes an id and request the TV show associated with that id. It results in a url like example.com/tv/23521. Looking at tmdb's own site their URL structure seems to something like "id-slug-title". Regardless of what comes after the ID it still redirects you to the right page.
How is that done? It would seem that it takes in the URL, splits it at "-" and uses the first parameter as ID. I am not sure how to do that in Flask though. I was thinking of using before and after request methods, but I'm worried that will just make unnecessary API calls. In order to get the slug title, I would have to make at least one call with the ID to get the title and then slugify that title.

Answer 1

The route accepts both an id and a slug, where the slug is optional:
#app.route('/tv/<int:id>', defaults={'slug': None})
#app.route('/tv/<int:id>-<slug>')
def tv(id, slug):
# ...
Note that you don't have to do any splitting yourself; the route matches if there is an integer number followed by a dash and some more text, or if it is just a number.
Only the id parameter is needed to find the right page. The slug is simply checked against the 'canonical' and you are redirected if it doesn't match:
page = load_page(id)
if slug != page.slug:
return redirect(url_for('tv', id=id, slug=page.slug))
Don't recalculate the slug each time, just store that in the database. You'll have to load the page info anyway for you to be able to serve it.
You could put that behaviour in a decorator and pass in the loaded page data into the view:
#app.route('/tv/<int:id>', defaults={'slug': None})
#app.route('/tv/<int:id>-<slug>')
#tv_page
def tv(page):
# ...
with tv_page then handling the parameters:
from functools import wraps
def tv_page(view_func):
#wraps(view_func)
def wrapper(id, slug):
page = load_page(id)
if slug != page.slug:
return redirect(url_for('tv', id=id, slug=page.slug))
return view_func(page)
return wrapper