diff --git a/CHANGES.md b/CHANGES.md
index 17ae711d6..b69b5a18c 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -1,10 +1,17 @@
 # Changes
 
 ## Unreleased - 2021-xx-xx
+### Added
+* Add extractors for `Uri` and `Method`. [#2263]
+* Add extractor for `ConnectionInfo` and `PeerAddr`. [#2263]
+
 ### Changed
 * Change compression algorithm features flags. [#2250]
+* Deprecate `App::data` and `App::data_factory`. [#2271]
 
 [#2250]: https://github.com/actix/actix-web/pull/2250
+[#2271]: https://github.com/actix/actix-web/pull/2271
+[#2263]: https://github.com/actix/actix-web/pull/2263
 
 
 ## 4.0.0-beta.7 - 2021-06-17
diff --git a/Cargo.toml b/Cargo.toml
index 770c9a050..320751c66 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -103,7 +103,7 @@ time = { version = "0.2.23", default-features = false, features = ["std"] }
 url = "2.1"
 
 [dev-dependencies]
-actix-test = { version = "0.1.0-beta.2", features = ["openssl", "rustls"] }
+actix-test = { version = "0.1.0-beta.3", features = ["openssl", "rustls"] }
 awc = { version = "3.0.0-beta.6", features = ["openssl"] }
 
 brotli2 = "0.3.2"
diff --git a/actix-files/Cargo.toml b/actix-files/Cargo.toml
index 44c29dc92..65dce628b 100644
--- a/actix-files/Cargo.toml
+++ b/actix-files/Cargo.toml
@@ -36,4 +36,4 @@ percent-encoding = "2.1"
 [dev-dependencies]
 actix-rt = "2.2"
 actix-web = "4.0.0-beta.7"
-actix-test = "0.1.0-beta.2"
+actix-test = "0.1.0-beta.3"
diff --git a/actix-test/CHANGES.md b/actix-test/CHANGES.md
index 2276fe745..fa554ba2e 100644
--- a/actix-test/CHANGES.md
+++ b/actix-test/CHANGES.md
@@ -3,6 +3,10 @@
 ## Unreleased - 2021-xx-xx
 
 
+## 0.1.0-beta.3 - 2021-06-20
+* No significant changes from `0.1.0-beta.2`.
+
+
 ## 0.1.0-beta.2 - 2021-04-17
 * No significant changes from `0.1.0-beta.1`.
 
diff --git a/actix-test/Cargo.toml b/actix-test/Cargo.toml
index 607038377..ca814e0e5 100644
--- a/actix-test/Cargo.toml
+++ b/actix-test/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "actix-test"
-version = "0.1.0-beta.2"
+version = "0.1.0-beta.3"
 authors = [
     "Nikolay Kim <fafhrd91@gmail.com>",
     "Rob Ede <robjtede@icloud.com>",
diff --git a/actix-web-actors/CHANGES.md b/actix-web-actors/CHANGES.md
index a7ee7a9e1..decbe2219 100644
--- a/actix-web-actors/CHANGES.md
+++ b/actix-web-actors/CHANGES.md
@@ -1,6 +1,9 @@
 # Changes
 
 ## Unreleased - 2021-xx-xx
+* Update `actix` to `0.12`. [#2277]
+
+[#2277]: https://github.com/actix/actix-web/pull/2277
 
 
 ## 4.0.0-beta.5 - 2021-06-17
diff --git a/actix-web-actors/Cargo.toml b/actix-web-actors/Cargo.toml
index 159b10d58..669cd4001 100644
--- a/actix-web-actors/Cargo.toml
+++ b/actix-web-actors/Cargo.toml
@@ -16,7 +16,7 @@ name = "actix_web_actors"
 path = "src/lib.rs"
 
 [dependencies]
-actix = { version = "0.11.0-beta.3", default-features = false }
+actix = { version = "0.12.0", default-features = false }
 actix-codec = "0.4.0"
 actix-http = "3.0.0-beta.7"
 actix-web = { version = "4.0.0-beta.7", default-features = false }
@@ -29,7 +29,7 @@ tokio = { version = "1", features = ["sync"] }
 
 [dev-dependencies]
 actix-rt = "2.2"
-actix-test = "0.1.0-beta.2"
+actix-test = "0.1.0-beta.3"
 
 awc = { version = "3.0.0-beta.6", default-features = false }
 env_logger = "0.8"
diff --git a/actix-web-codegen/Cargo.toml b/actix-web-codegen/Cargo.toml
index 29565f74a..327f16bc5 100644
--- a/actix-web-codegen/Cargo.toml
+++ b/actix-web-codegen/Cargo.toml
@@ -20,7 +20,7 @@ proc-macro2 = "1"
 
 [dev-dependencies]
 actix-rt = "2.2"
-actix-test = "0.1.0-beta.2"
+actix-test = "0.1.0-beta.3"
 actix-utils = "3.0.0"
 actix-web = "4.0.0-beta.7"
 
diff --git a/awc/Cargo.toml b/awc/Cargo.toml
index 7d6ee52c4..26c625a05 100644
--- a/awc/Cargo.toml
+++ b/awc/Cargo.toml
@@ -83,7 +83,7 @@ actix-http-test = { version = "3.0.0-beta.4", features = ["openssl"] }
 actix-utils = "3.0.0"
 actix-server = "2.0.0-beta.3"
 actix-tls = { version = "3.0.0-beta.5", features = ["openssl", "rustls"] }
-actix-test = { version = "0.1.0-beta.2", features = ["openssl", "rustls"] }
+actix-test = { version = "0.1.0-beta.3", features = ["openssl", "rustls"] }
 
 brotli2 = "0.3.2"
 env_logger = "0.8"
diff --git a/src/app.rs b/src/app.rs
index 357d45eeb..8c622dd36 100644
--- a/src/app.rs
+++ b/src/app.rs
@@ -98,13 +98,18 @@ where
     ///         web::resource("/index.html").route(
     ///             web::get().to(index)));
     /// ```
+    #[deprecated(since = "4.0.0", note = "Use `.app_data(Data::new(val))` instead.")]
     pub fn data<U: 'static>(self, data: U) -> Self {
         self.app_data(Data::new(data))
     }
 
-    /// Set application data factory. This function is
-    /// similar to `.data()` but it accepts data factory. Data object get
-    /// constructed asynchronously during application initialization.
+    /// Add application data factory. This function is similar to `.data()` but it accepts a
+    /// "data factory". Data values are constructed asynchronously during application
+    /// initialization, before the server starts accepting requests.
+    #[deprecated(
+        since = "4.0.0",
+        note = "Construct data value before starting server and use `.app_data(Data::new(val))` instead."
+    )]
     pub fn data_factory<F, Out, D, E>(mut self, data: F) -> Self
     where
         F: Fn() -> Out + 'static,
@@ -518,6 +523,8 @@ mod tests {
         assert_eq!(resp.status(), StatusCode::CREATED);
     }
 
+    // allow deprecated App::data
+    #[allow(deprecated)]
     #[actix_rt::test]
     async fn test_data_factory() {
         let srv = init_service(
@@ -541,6 +548,8 @@ mod tests {
         assert_eq!(resp.status(), StatusCode::INTERNAL_SERVER_ERROR);
     }
 
+    // allow deprecated App::data
+    #[allow(deprecated)]
     #[actix_rt::test]
     async fn test_data_factory_errors() {
         let srv = try_init_service(
diff --git a/src/app_service.rs b/src/app_service.rs
index ca6f36202..a9247b19f 100644
--- a/src/app_service.rs
+++ b/src/app_service.rs
@@ -349,6 +349,8 @@ mod tests {
         }
     }
 
+    // allow deprecated App::data
+    #[allow(deprecated)]
     #[actix_rt::test]
     async fn test_drop_data() {
         let data = Arc::new(AtomicBool::new(false));
diff --git a/src/config.rs b/src/config.rs
index 4bd76f2b7..d22bc856e 100644
--- a/src/config.rs
+++ b/src/config.rs
@@ -116,6 +116,7 @@ impl AppConfig {
         AppConfig { secure, host, addr }
     }
 
+    /// Needed in actix-test crate.
     #[doc(hidden)]
     pub fn __priv_test_new(secure: bool, host: String, addr: SocketAddr) -> Self {
         AppConfig::new(secure, host, addr)
diff --git a/src/data.rs b/src/data.rs
index f09a88891..51db6ce4c 100644
--- a/src/data.rs
+++ b/src/data.rs
@@ -154,6 +154,8 @@ mod tests {
         web, App, HttpResponse,
     };
 
+    // allow deprecated App::data
+    #[allow(deprecated)]
     #[actix_rt::test]
     async fn test_data_extractor() {
         let srv = init_service(App::new().data("TEST".to_string()).service(
@@ -221,6 +223,8 @@ mod tests {
         assert_eq!(resp.status(), StatusCode::INTERNAL_SERVER_ERROR);
     }
 
+    // allow deprecated App::data
+    #[allow(deprecated)]
     #[actix_rt::test]
     async fn test_route_data_extractor() {
         let srv = init_service(
@@ -250,6 +254,8 @@ mod tests {
         assert_eq!(resp.status(), StatusCode::INTERNAL_SERVER_ERROR);
     }
 
+    // allow deprecated App::data
+    #[allow(deprecated)]
     #[actix_rt::test]
     async fn test_override_data() {
         let srv =
diff --git a/src/extract.rs b/src/extract.rs
index 45cb330a3..d7b67cd90 100644
--- a/src/extract.rs
+++ b/src/extract.rs
@@ -1,12 +1,14 @@
 //! Request extractors
 
 use std::{
+    convert::Infallible,
     future::Future,
     pin::Pin,
     task::{Context, Poll},
 };
 
-use actix_utils::future::{ready, Ready};
+use actix_http::http::{Method, Uri};
+use actix_utils::future::{ok, Ready};
 use futures_core::ready;
 
 use crate::{dev::Payload, Error, HttpRequest};
@@ -216,14 +218,58 @@ where
     }
 }
 
+/// Extract the request's URI.
+///
+/// # Examples
+/// ```
+/// use actix_web::{http::Uri, web, App, Responder};
+///
+/// async fn handler(uri: Uri) -> impl Responder {
+///     format!("Requested path: {}", uri.path())
+/// }
+///
+/// let app = App::new().default_service(web::to(handler));
+/// ```
+impl FromRequest for Uri {
+    type Error = Infallible;
+    type Future = Ready<Result<Self, Self::Error>>;
+    type Config = ();
+
+    fn from_request(req: &HttpRequest, _: &mut Payload) -> Self::Future {
+        ok(req.uri().clone())
+    }
+}
+
+/// Extract the request's method.
+///
+/// # Examples
+/// ```
+/// use actix_web::{http::Method, web, App, Responder};
+///
+/// async fn handler(method: Method) -> impl Responder {
+///     format!("Request method: {}", method)
+/// }
+///
+/// let app = App::new().default_service(web::to(handler));
+/// ```
+impl FromRequest for Method {
+    type Error = Infallible;
+    type Future = Ready<Result<Self, Self::Error>>;
+    type Config = ();
+
+    fn from_request(req: &HttpRequest, _: &mut Payload) -> Self::Future {
+        ok(req.method().clone())
+    }
+}
+
 #[doc(hidden)]
 impl FromRequest for () {
-    type Error = Error;
-    type Future = Ready<Result<(), Error>>;
+    type Error = Infallible;
+    type Future = Ready<Result<(), Infallible>>;
     type Config = ();
 
     fn from_request(_: &HttpRequest, _: &mut Payload) -> Self::Future {
-        ready(Ok(()))
+        ok(())
     }
 }
 
@@ -411,4 +457,18 @@ mod tests {
             .unwrap();
         assert!(r.is_err());
     }
+
+    #[actix_rt::test]
+    async fn test_uri() {
+        let req = TestRequest::default().uri("/foo/bar").to_http_request();
+        let uri = Uri::extract(&req).await.unwrap();
+        assert_eq!(uri.path(), "/foo/bar");
+    }
+
+    #[actix_rt::test]
+    async fn test_method() {
+        let req = TestRequest::default().method(Method::GET).to_http_request();
+        let method = Method::extract(&req).await.unwrap();
+        assert_eq!(method, Method::GET);
+    }
 }
diff --git a/src/info.rs b/src/info.rs
index c9ddf6ec4..c6ff54efe 100644
--- a/src/info.rs
+++ b/src/info.rs
@@ -1,13 +1,36 @@
-use std::cell::Ref;
+use std::{cell::Ref, convert::Infallible, net::SocketAddr};
 
-use crate::dev::{AppConfig, RequestHead};
-use crate::http::header::{self, HeaderName};
+use actix_utils::future::{err, ok, Ready};
+use derive_more::{Display, Error};
+
+use crate::{
+    dev::{AppConfig, Payload, RequestHead},
+    http::header::{self, HeaderName},
+    FromRequest, HttpRequest, ResponseError,
+};
 
 const X_FORWARDED_FOR: &[u8] = b"x-forwarded-for";
 const X_FORWARDED_HOST: &[u8] = b"x-forwarded-host";
 const X_FORWARDED_PROTO: &[u8] = b"x-forwarded-proto";
 
-/// `HttpRequest` connection information
+/// HTTP connection information.
+///
+/// `ConnectionInfo` implements `FromRequest` and can be extracted in handlers.
+///
+/// # Examples
+/// ```
+/// # use actix_web::{HttpResponse, Responder};
+/// use actix_web::dev::ConnectionInfo;
+///
+/// async fn handler(conn: ConnectionInfo) -> impl Responder {
+///     match conn.host() {
+///         "actix.rs" => HttpResponse::Ok().body("Welcome!"),
+///         "admin.actix.rs" => HttpResponse::Ok().body("Admin portal."),
+///         _ => HttpResponse::NotFound().finish()
+///     }
+/// }
+/// # let _svc = actix_web::web::to(handler);
+/// ```
 #[derive(Debug, Clone, Default)]
 pub struct ConnectionInfo {
     scheme: String,
@@ -187,6 +210,65 @@ impl ConnectionInfo {
     }
 }
 
+impl FromRequest for ConnectionInfo {
+    type Error = Infallible;
+    type Future = Ready<Result<Self, Self::Error>>;
+    type Config = ();
+
+    fn from_request(req: &HttpRequest, _: &mut Payload) -> Self::Future {
+        ok(req.connection_info().clone())
+    }
+}
+
+/// Extractor for peer's socket address.
+///
+/// Also see [`HttpRequest::peer_addr`].
+///
+/// # Examples
+/// ```
+/// # use actix_web::Responder;
+/// use actix_web::dev::PeerAddr;
+///
+/// async fn handler(peer_addr: PeerAddr) -> impl Responder {
+///     let socket_addr = peer_addr.0;
+///     socket_addr.to_string()
+/// }
+/// # let _svc = actix_web::web::to(handler);
+/// ```
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash, PartialOrd, Ord, Display)]
+#[display(fmt = "{}", _0)]
+pub struct PeerAddr(pub SocketAddr);
+
+impl PeerAddr {
+    /// Unwrap into inner `SocketAddr` value.
+    pub fn into_inner(self) -> SocketAddr {
+        self.0
+    }
+}
+
+#[derive(Debug, Display, Error)]
+#[non_exhaustive]
+#[display(fmt = "Missing peer address")]
+pub struct MissingPeerAddr;
+
+impl ResponseError for MissingPeerAddr {}
+
+impl FromRequest for PeerAddr {
+    type Error = MissingPeerAddr;
+    type Future = Ready<Result<Self, Self::Error>>;
+    type Config = ();
+
+    fn from_request(req: &HttpRequest, _: &mut Payload) -> Self::Future {
+        match req.peer_addr() {
+            Some(addr) => ok(PeerAddr(addr)),
+            None => {
+                log::error!("Missing peer address.");
+                err(MissingPeerAddr)
+            }
+        }
+    }
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;
@@ -239,4 +321,25 @@ mod tests {
         let info = req.connection_info();
         assert_eq!(info.scheme(), "https");
     }
+
+    #[actix_rt::test]
+    async fn test_conn_info() {
+        let req = TestRequest::default()
+            .uri("http://actix.rs/")
+            .to_http_request();
+        let conn_info = ConnectionInfo::extract(&req).await.unwrap();
+        assert_eq!(conn_info.scheme(), "http");
+    }
+
+    #[actix_rt::test]
+    async fn test_peer_addr() {
+        let addr = "127.0.0.1:8080".parse().unwrap();
+        let req = TestRequest::default().peer_addr(addr).to_http_request();
+        let peer_addr = PeerAddr::extract(&req).await.unwrap();
+        assert_eq!(peer_addr, PeerAddr(addr));
+
+        let req = TestRequest::default().to_http_request();
+        let res = PeerAddr::extract(&req).await;
+        assert!(res.is_err());
+    }
 }
diff --git a/src/lib.rs b/src/lib.rs
index 4bcef3988..9d8bf62e7 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -131,7 +131,7 @@ pub mod dev {
     pub use crate::config::{AppConfig, AppService};
     #[doc(hidden)]
     pub use crate::handler::Handler;
-    pub use crate::info::ConnectionInfo;
+    pub use crate::info::{ConnectionInfo, PeerAddr};
     pub use crate::rmap::ResourceMap;
     pub use crate::service::{HttpServiceFactory, ServiceRequest, ServiceResponse, WebService};
 
diff --git a/src/request.rs b/src/request.rs
index 42c722c46..bff66f08e 100644
--- a/src/request.rs
+++ b/src/request.rs
@@ -60,18 +60,6 @@ impl HttpRequest {
             }),
         }
     }
-
-    #[doc(hidden)]
-    pub fn __priv_test_new(
-        path: Path<Url>,
-        head: Message<RequestHead>,
-        rmap: Rc<ResourceMap>,
-        config: AppConfig,
-        app_data: Rc<Extensions>,
-    ) -> HttpRequest {
-        let app_state = AppInitServiceState::new(rmap, config);
-        Self::new(path, head, app_state, app_data)
-    }
 }
 
 impl HttpRequest {
@@ -723,6 +711,8 @@ mod tests {
         assert_eq!(body, Bytes::from_static(b"1"));
     }
 
+    // allow deprecated App::data
+    #[allow(deprecated)]
     #[actix_rt::test]
     async fn test_extensions_dropped() {
         struct Tracker {
diff --git a/src/resource.rs b/src/resource.rs
index 8c2b83b60..9455895e9 100644
--- a/src/resource.rs
+++ b/src/resource.rs
@@ -196,6 +196,7 @@ where
     ///           ));
     /// }
     /// ```
+    #[deprecated(since = "4.0.0", note = "Use `.app_data(Data::new(val))` instead.")]
     pub fn data<U: 'static>(self, data: U) -> Self {
         self.app_data(Data::new(data))
     }
@@ -694,6 +695,8 @@ mod tests {
         assert_eq!(resp.status(), StatusCode::NO_CONTENT);
     }
 
+    // allow deprecated App::data
+    #[allow(deprecated)]
     #[actix_rt::test]
     async fn test_data() {
         let srv = init_service(
@@ -726,6 +729,8 @@ mod tests {
         assert_eq!(resp.status(), StatusCode::OK);
     }
 
+    // allow deprecated App::data
+    #[allow(deprecated)]
     #[actix_rt::test]
     async fn test_data_default_service() {
         let srv = init_service(
diff --git a/src/response/response.rs b/src/response/response.rs
index 9dd804be0..9a3bb2874 100644
--- a/src/response/response.rs
+++ b/src/response/response.rs
@@ -49,7 +49,10 @@ impl HttpResponse<AnyBody> {
     /// Create an error response.
     #[inline]
     pub fn from_error(error: impl Into<Error>) -> Self {
-        error.into().as_response_error().error_response()
+        let error = error.into();
+        let mut response = error.as_response_error().error_response();
+        response.error = Some(error);
+        response
     }
 }
 
diff --git a/src/scope.rs b/src/scope.rs
index 412c01d95..86304074b 100644
--- a/src/scope.rs
+++ b/src/scope.rs
@@ -146,6 +146,7 @@ where
     ///     );
     /// }
     /// ```
+    #[deprecated(since = "4.0.0", note = "Use `.app_data(Data::new(val))` instead.")]
     pub fn data<U: 'static>(self, data: U) -> Self {
         self.app_data(Data::new(data))
     }
@@ -990,6 +991,8 @@ mod tests {
         );
     }
 
+    // allow deprecated App::data
+    #[allow(deprecated)]
     #[actix_rt::test]
     async fn test_override_data() {
         let srv = init_service(App::new().data(1usize).service(
@@ -1008,6 +1011,8 @@ mod tests {
         assert_eq!(resp.status(), StatusCode::OK);
     }
 
+    // allow deprecated App::data
+    #[allow(deprecated)]
     #[actix_rt::test]
     async fn test_override_data_default_service() {
         let srv = init_service(App::new().data(1usize).service(
diff --git a/src/service.rs b/src/service.rs
index 9ebeb77df..8d73a87fa 100644
--- a/src/service.rs
+++ b/src/service.rs
@@ -74,12 +74,6 @@ impl ServiceRequest {
         Self { req, payload }
     }
 
-    /// Construct service request.
-    #[doc(hidden)]
-    pub fn __priv_test_new(req: HttpRequest, payload: Payload) -> Self {
-        Self::new(req, payload)
-    }
-
     /// Deconstruct request into parts
     #[inline]
     pub fn into_parts(self) -> (HttpRequest, Payload) {
@@ -661,6 +655,8 @@ mod tests {
         assert_eq!(resp.status(), http::StatusCode::NOT_FOUND);
     }
 
+    // allow deprecated App::data
+    #[allow(deprecated)]
     #[actix_rt::test]
     async fn test_service_data() {
         let srv =
diff --git a/src/test.rs b/src/test.rs
index de97dc8aa..05a4ba7f2 100644
--- a/src/test.rs
+++ b/src/test.rs
@@ -839,6 +839,8 @@ mod tests {
         assert!(res.status().is_success());
     }
 
+    // allow deprecated App::data
+    #[allow(deprecated)]
     #[actix_rt::test]
     async fn test_server_data() {
         async fn handler(data: web::Data<usize>) -> impl Responder {
diff --git a/src/types/payload.rs b/src/types/payload.rs
index 3b0d1d6c6..87378701b 100644
--- a/src/types/payload.rs
+++ b/src/types/payload.rs
@@ -398,6 +398,8 @@ mod tests {
         assert!(cfg.check_mimetype(&req).is_ok());
     }
 
+    // allow deprecated App::data
+    #[allow(deprecated)]
     #[actix_rt::test]
     async fn test_config_recall_locations() {
         async fn bytes_handler(_: Bytes) -> impl Responder {
diff --git a/tests/test_error_propagation.rs b/tests/test_error_propagation.rs
new file mode 100644
index 000000000..1b56615a0
--- /dev/null
+++ b/tests/test_error_propagation.rs
@@ -0,0 +1,100 @@
+use actix_utils::future::{ok, Ready};
+use actix_web::dev::{Service, ServiceRequest, ServiceResponse, Transform};
+use actix_web::test::{call_service, init_service, TestRequest};
+use actix_web::{HttpResponse, ResponseError};
+use futures_util::lock::Mutex;
+use std::future::Future;
+use std::pin::Pin;
+use std::sync::Arc;
+use std::task::{Context, Poll};
+
+#[derive(Debug, Clone)]
+pub struct MyError;
+
+impl ResponseError for MyError {}
+
+impl std::fmt::Display for MyError {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        write!(f, "A custom error")
+    }
+}
+
+#[actix_web::get("/test")]
+async fn test() -> Result<actix_web::HttpResponse, actix_web::error::Error> {
+    Err(MyError)?;
+    Ok(HttpResponse::NoContent().finish())
+}
+
+#[derive(Clone)]
+pub struct SpyMiddleware(Arc<Mutex<Option<bool>>>);
+
+impl<S, B> Transform<S, ServiceRequest> for SpyMiddleware
+where
+    S: Service<ServiceRequest, Response = ServiceResponse<B>, Error = actix_web::Error>,
+    S::Future: 'static,
+    B: 'static,
+{
+    type Response = ServiceResponse<B>;
+    type Error = actix_web::Error;
+    type Transform = Middleware<S>;
+    type InitError = ();
+    type Future = Ready<Result<Self::Transform, Self::InitError>>;
+
+    fn new_transform(&self, service: S) -> Self::Future {
+        ok(Middleware {
+            was_error: self.0.clone(),
+            service,
+        })
+    }
+}
+
+#[doc(hidden)]
+pub struct Middleware<S> {
+    was_error: Arc<Mutex<Option<bool>>>,
+    service: S,
+}
+
+impl<S, B> Service<ServiceRequest> for Middleware<S>
+where
+    S: Service<ServiceRequest, Response = ServiceResponse<B>, Error = actix_web::Error>,
+    S::Future: 'static,
+    B: 'static,
+{
+    type Response = ServiceResponse<B>;
+    type Error = actix_web::Error;
+    type Future = Pin<Box<dyn Future<Output = Result<Self::Response, Self::Error>>>>;
+
+    fn poll_ready(&self, cx: &mut Context<'_>) -> Poll<Result<(), Self::Error>> {
+        self.service.poll_ready(cx)
+    }
+
+    fn call(&self, req: ServiceRequest) -> Self::Future {
+        let lock = self.was_error.clone();
+        let response_future = self.service.call(req);
+        Box::pin(async move {
+            let response = response_future.await;
+            if let Ok(success) = &response {
+                *lock.lock().await = Some(success.response().error().is_some());
+            }
+            response
+        })
+    }
+}
+
+#[actix_rt::test]
+async fn error_cause_should_be_propagated_to_middlewares() {
+    let lock = Arc::new(Mutex::new(None));
+    let spy_middleware = SpyMiddleware(lock.clone());
+
+    let app = init_service(
+        actix_web::App::new()
+            .wrap(spy_middleware.clone())
+            .service(test),
+    )
+    .await;
+
+    call_service(&app, TestRequest::with_uri("/test").to_request()).await;
+
+    let was_error_captured = lock.lock().await.unwrap();
+    assert!(was_error_captured);
+}
diff --git a/tests/test_server.rs b/tests/test_server.rs
index 520eb5ce2..9131d1f29 100644
--- a/tests/test_server.rs
+++ b/tests/test_server.rs
@@ -1028,6 +1028,8 @@ async fn test_normalize() {
     assert!(response.status().is_success());
 }
 
+// allow deprecated App::data
+#[allow(deprecated)]
 #[actix_rt::test]
 async fn test_data_drop() {
     use std::sync::{