Handling Error with appstate

[0xpr03]

How do you typically handle the following requirements in axum?

• early-return in handlers when no valid login could be found
• use some kind of IntoResponse AppError
• render that error for all handlers with a template system that requires access to the AppState and also possibly more context (for example the Url when redirecting towards a login that should also send you back to your original page after logging in).

It currently looks like I would have to use a HandleError for every handler, creating a ton of .route("foo",HandleError(error_handler,app_logic)). Something like the generalized HandleErrorLayer (which also has state access) would be nice here - but obviously won't work for my non-service. (is it even a good idea to make every route call a service?)

[davidpdrsn]

early-return in handlers when no valid login could be found

Make your own extractor or middleware.

use some kind of IntoResponse AppError

IntoResponse intentionally doesn’t access to state so you have to pass that in some other way.

render that error for all handlers with a template system that requires access to the AppState and also possibly more context

This also sounds like a middleware to me. Perhaps the handler sets a response extension which is picked up by a middleware and then converted into a response.

[0xpr03]

Abstracting the login-requirements with a middleware probably is a good idea - I just feared creating my own. Using another one for error handling doesn't sound bad, then I could even keep my IntoResponse Error-Enum.

[davidpdrsn]

It’s pretty easy to make a middleware with https://docs.rs/axum/0.6.20/axum/middleware/fn.from_fn.html