Attach middleware to route groups

[notramo]

For example, all admin: routes could have a middleware that checks user role, and all api: routes could have one that checks that accepted content-type is JSON.

[ellmetha]

The idea of middlewares is that they are applied to all incoming requests before routes are actually resolved and after a response has been produced by handlers (if a handler is indeed matched by the current route). If some handlers only need certain behaviors or checks, I would suggest making use of a base handler class or a shared concern module.

[notramo]

The problem with this approach is that it's easy to forget to add a module to a given route. Also, if a handler is moved to another route group, it's easy to forget to change the imported modules.
The base idea for this proposal is to attach middleware to the handlers, based on the route path.

However, if you think that it's out of scope for this project, it's not a must-have, but a nice-to-have indeed, so I'm closing this.