Is it safe to rely on Application::_router::stack to get the list of registered routes?

[ericmorand]

I've seen multiple answers on different websites that recommends using Application::_router::stack to get the list of registered routes. While it works perfectly, i'm not convinced that it is safe and that it won't break in the future:

• _router starts with a _ which usually denotes a private property
• _router is of type any in the TypeScript definition which may mean that there is no guarantee that it has a stack attribute

Is it safe to use this method to get the list of registered routes?

If not, what is the officially recommended way to retrieve such a list?

Thanks by advance.

[dougwilson]

Unfortunately it is a nuanced question, for sure. Officially, there is no documented/supported way to get the list of routes. But the Express.js project treads carefully with changing any data that is accessible, even if it's through an underscore-prefixed property. This is because a large project like this will end up with folks relying on these things and we really don't want to break folks. And, in fact, the router was moved back to a non-underscore-prefixed property in the developing next versions of express, and it's the same object and structure; that should hopefully provide an indication that the underscore part is effectively meaningless :)

[ericmorand]

And, in fact, the router was moved back to a non-underscore-prefixed property in the developing next versions of express

It's awesome news.

and it's the same object and structure;

Even better. It means that the types library for the next major version will be able to safely type router and give us a supported way to retrieve the list of registered routes.

Thanks a lot for the answer.