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Python Django Forms Model Forms Handling Multiple Form Classes

Posted by Owen Orsetti
Owen Orsetti
19,102 Points

Using the "|" operator in Django 2.0's "Path"

In this step, Kenneth has us write a URL for creating a question that includes "mc|tf" to determine the question type.

Since the urls method he uses has been depricated in Django 2.0, I have been using the path method instead, usually to similar results.

However, try as I might I cannot get the "|" part of this URL from this step to work using path.

As an alternative, you can import and use re_path instead, which allows you to use regular expressions in exactly the same way as Kenneth is using:

from django.urls import path, re_path

re_path(r'(?P<quiz_pk>\d+)/create_question/(?P<question_type>mc|tf)/$', views.create_question, name='create_question'),

So this post serves 2 purposes:

1) To anyone struggling to get path working with the "|" part of the URL, you can use r_path instead.

2) If anyone knows how to use path with "|" please let me know because I wasn't able to figure it out and I would like to know!

Cheers, Owen

1 Answer

Jonatan Witoszek
Jonatan Witoszek
15,384 Points
Jonatan Witoszek
Jonatan Witoszek
15,384 Points

There's no escaping regular expressions in this case. However we can still use | with path. To do so we have to define custom path conventer like this:

class QuestionType:
    regex = 'mc|tf'

    def to_python(self, value):
        return str(value)

    def to_url(self, value):
        return value

Then we have to register our conventer:

register_converter(QuestionType, 'question')

(the question string here is what we will use in path instead of, for example int)

After that we can use our registered conventer in path:

path('<int:quiz_pk>/create_question/<question:question_type>',
         views.create_question, name='create_question'),
Owen Orsetti
Owen Orsetti
19,102 Points

Nice, thanks! Seems like a bit overkill for this situation, since r_path works, but I didn't know you could create custom path converters.

Thanks! Owen