Unable to add a breadcrumb from actix-web middleware

[ferologics]

Environment

actix-web 4.4.0
actix-web-lab 0.19.1
sentry-tracing 0.31.7
sentry-actix 0.31.6

Steps to Reproduce

1. intercept incoming request with actix-web-lab middleware
2. call sentry::add_breadcrumb(incoming_request) before next.call(req).await
3. server executes logic ... error is thrown
4. use tracing::error!(...) to capture error message
5. sentry reported error has no incoming request breadcrumb

Expected Result

Breadcrumb attached with the reported error.

Actual Result

Breadcrumb is missing.

Workaround

pass the incoming_request breadcrumb in actix request extensions and sentry::add_breadcrumb from within the request execution context ([middleware -> [ request ] ])

Notes

I suspect that the middleware uses a different Hub from the request:

Because actix is generally working with non sendable objects and highly concurrent this middleware creates a new hub per request. As a result many of the sentry integrations such as breadcrumbs do not work unless you bind the actix hub
(source)

We tried binding the current Hub inside middleware but it raises an issue with the ServiceRequest which is not Send.

Is there a way to attach this breadcrumb directly from middleware?

[ferologics]

@lcian / @Swatinem i tried this in updated sentry v0.37.0 but not seeing the breadcrumb 🤔

we're using:

.wrap(actix_web::middleware::from_fn(
    middleware::log_incoming_request,
))

where log_incoming_request calls sentry::add_breadcrumb(incoming_req);

before	after

[lcian]

@ferologics are you applying the sentry layer as the last middleware in the chain?

[ferologics]

@lcian it's the second thing that's applied:

        App::new()
            // separate sentry reports for each request by wrapping the app in sentry middleware
            // the middleware ensures Hub isolation and more metadata on the scope for each request
            // https://github.com/getsentry/sentry-rust/issues/616#issuecomment-1722987627
            .wrap(
                sentry_actix::Sentry::builder()
                    // disables automatic error capturing (more context in above issue)
                    // if set to `true` errors would be reported to sentry automatically
                    // this magic is not desired, it over-reports errors, and limits
                    // our control over how and what errors are captured
                    // ────────────────────────────────────────────────────────────────────────
                    // we disable this behaviour to manually capture breadcrumbs with `tracing::warn!()`
                    // and errors with `tracing::error!()` (this is done in `fn error_response`)
                    .capture_server_errors(false)
                    .finish(),
            )
            .wrap(actix_web::middleware::from_fn(
                middleware::log_incoming_request,
            ))

should we move it to be the last? (i think i saw a note in the docs somewhere while reading your changes)

edit: yeah i see it mentioned here. let me try registering the middleware as last.

[lcian]

Yes please. Sorry should've mentioned it in the changelog too.