They'd previously see the nested URI as we mutated the request. Now we
always route based on the nested URI (if present) without mutating the
request. Also meant we could get rid of `OriginalUri` which is nice.
Previously, on `main`, this wouldn't compile:
```rust
let app = route("/", get(handler))
.layer(
ServiceBuilder::new()
.timeout(Duration::from_secs(10))
.into_inner(),
)
.handle_error(...)
.route(...); // <-- doesn't work
```
That is because `handle_error` would be
`axum::service::ServiceExt::handle_error` which returns `HandleError<_,
_, _, HandleErrorFromService>` which does _not_ implement `RoutingDsl`.
So you couldn't call `route`. This was caused by
https://github.com/tokio-rs/axum/pull/120.
Basically `handle_error` when called on a `RoutingDsl`, the resulting
service should also implement `RoutingDsl`, but if called on another
random service it should _not_ implement `RoutingDsl`.
I don't think thats possible by having `handle_error` on `ServiceExt`
which is implemented for any service, since all axum routers are also
services by design.
This resolves the issue by removing `ServiceExt` and moving its methods
to `RoutingDsl`. Then we have more tight control over what has a
`handle_error` method.
`service::OnMethod` now also has a `handle_error` so you can still
handle errors from random services, by doing
`service::any(svc).handle_error(...)`.
With this you'll be able to do:
```rust
let one = route("/foo", get(|| async { "foo" }))
.route("/bar", get(|| async { "bar" }));
let two = route("/baz", get(|| async { "baz" }));
let app = one.or(two);
```
Fixes https://github.com/tokio-rs/axum/issues/101
