Question

I have a URL binded to a handler in Tornado. e.g.

(r'/browse/article/([a-zA-Z0-9_-]+)/([0-9]*)', ArticleHandler),

However, the number of arguments is not fixed, such that some will be /browse/article/blah, others will be /browse/article/blah/2. In other words, the last argument may or may not exist.

Is it still possible to use a single handler to handle this case? If so, how should I formulate the regex string to match all possible cases?

Answer 1

Try this:

(r'/browse/article/([a-zA-Z0-9_-]+)(?:/([0-9]*))?', ArticleHandler),

This makes the last segment optional while keeping the capturing parentheses intact, in case they are used for something later.