I cannot successfully modify the response in middleware

[SpaceAceMonkey]

Edit: I started over with the middleware example, added the into_parts() code, then fixed errors one at a time. It appears to be working, now, but I have absolutely no idea what is different this time than the previous time(s) I tried copy/pasting the middleware example from the documentation, or from the issue I linked to, below. I think the documentation needs a working example of modifying the response. If it exists, I was unable to find it.

I am using actix-web 4.3.0.

I am having a nightmare of a time modifying the response in middleware. At first, I based my effort on the middleware example in the documentation, but when I tried to adapt that example by creating a new ServiceResponse, I would up in type-error hell. I managed to solve some of the issues by using a concrete type in place of the B generic in the middleware, but I still had problems with the HttpResponse and the ServiceResponse not getting along.

Finally, I found this discussion: 2834. I changed my code to extract the pieces from res as shown on that page, and I managed to get the code to compile, but now I have a new problem. Whether I use an annotation, or .wrap(), I am now receiving this error:

expected `[async block@src/middleware.rs:64:13: 112:14]` to be a future that resolves to `Result<ServiceResponse<actix_web::web::Bytes>, actix_web::Error>`, but it resolves to `Result<ServiceResponse, _>`
expected enum `Result<ServiceResponse<actix_web::web::Bytes>, actix_web::Error>`
   found enum `Result<ServiceResponse<BoxBody>, _>`
required for the cast from `[async block@src/middleware.rs:64:13: 112:14]` to the object type `dyn futures::Future<Output = Result<ServiceResponse<actix_web::web::Bytes>, actix_web::Error>>

I finally tried copy/pasting the completed middleware from the linked discussion, but I am still having this issue. My code is currently identical to the code from 2834, minus the redis stuff, and with the ok() added to the unwrap as discussed on that page.

error[E0271]: type mismatch resolving `<actix_web::resource::ResourceService as actix_web::dev::Service<ServiceRequest>>::Response == ServiceResponse<actix_web::web::Bytes>`
   --> src/routes.rs:5:19
    |
5   | #[get("/", wrap = "SomethingMiddlewareFactory")]
    | ------------------^^^^^^^^^^^^^^^^^^^^^^^^^^^^--
    | |                 |
    | |                 expected struct `actix_web::web::Bytes`, found struct `BoxBody`
    | required by a bound introduced by this call
    |
    = note: expected struct `ServiceResponse<actix_web::web::Bytes>`
               found struct `ServiceResponse<BoxBody>`
note: required for `SomethingMiddlewareFactory` to implement `Transform<actix_web::resource::ResourceService, ServiceRequest>`
   --> src/middleware.rs:129:9
    |
129 | impl<S> Transform<S, ServiceRequest> for SomethingMiddlewareFactory
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^     ^^^^^^^^^^^^^^^^^^^^^^^^^^
note: required by a bound in `Resource::<T>::wrap`
   --> /home/nonna/.cargo/registry/src/github.com-1ecc6299db9ec823/actix-web-4.3.0/src/resource.rs:269:12
    |
269 |           M: Transform<
    |  ____________^
270 | |                 T::Service,
271 | |                 ServiceRequest,
272 | |                 Response = ServiceResponse<B>,
273 | |                 Error = Error,
274 | |                 InitError = (),
275 | |             > + 'static,
    | |_____________^ required by this bound in `Resource::<T>::wrap`