allow parent data containers to be accessed from child scopes

CHANGES.md

@@ -1,16 +1,24 @@
 # Changes
 
+## [Unreleased]
+
+### Changed
+
+* Resources and Scopes can now access non-overridden data types set on App (or containing scopes) when setting their own data. [#1486]
+
 ## [3.0.0-alpha.2] - 2020-05-08
 
 ### Changed
 
 * `{Resource,Scope}::default_service(f)` handlers now support app data extraction. [#1452]
 * Implement `std::error::Error` for our custom errors [#1422]
-* NormalizePath middleware now appends trailing / so that routes of form /example/ respond to /example requests.
+* NormalizePath middleware now appends trailing / so that routes of form /example/ respond to /example requests. [#1433]
 * Remove the `failure` feature and support.
 
 [#1422]: https://github.com/actix/actix-web/pull/1422
+[#1433]: https://github.com/actix/actix-web/pull/1433
 [#1452]: https://github.com/actix/actix-web/pull/1452
+[#1486]: https://github.com/actix/actix-web/pull/1486
 
 ## [3.0.0-alpha.1] - 2020-03-11
 

Cargo.toml

@@ -101,6 +101,7 @@ time = { version = "0.2.7", default-features = false, features = ["std"] }
 url = "2.1"
 open-ssl = { version="0.10", package = "openssl", optional = true }
 rust-tls = { version = "0.17.0", package = "rustls", optional = true }
+tinyvec = { version = "0.3", features = ["alloc"] }
 
 [dev-dependencies]
 actix = "0.10.0-alpha.1"

src/app_service.rs

@@ -245,7 +245,7 @@ where
             inner.path.reset();
             inner.head = head;
             inner.payload = payload;
-            inner.app_data = self.data.clone();
+            inner.app_data.push(self.data.clone());
             req
         } else {
             HttpRequest::new(

src/request.rs

@@ -6,6 +6,7 @@ use actix_http::http::{HeaderMap, Method, Uri, Version};
 use actix_http::{Error, Extensions, HttpMessage, Message, Payload, RequestHead};
 use actix_router::{Path, Url};
 use futures::future::{ok, Ready};
+use tinyvec::TinyVec;
 
 use crate::config::AppConfig;
 use crate::error::UrlGenerationError;
@@ -21,7 +22,7 @@ pub(crate) struct HttpRequestInner {
     pub(crate) head: Message<RequestHead>,
     pub(crate) path: Path<Url>,
     pub(crate) payload: Payload,
-    pub(crate) app_data: Rc<Extensions>,
+    pub(crate) app_data: TinyVec<[Rc<Extensions>; 4]>,
     rmap: Rc<ResourceMap>,
     config: AppConfig,
     pool: &'static HttpRequestPool,
@@ -38,13 +39,16 @@ impl HttpRequest {
         app_data: Rc<Extensions>,
         pool: &'static HttpRequestPool,
     ) -> HttpRequest {
+        let mut data = TinyVec::<[Rc<Extensions>; 4]>::new();
+        data.push(app_data);
+
         HttpRequest(Rc::new(HttpRequestInner {
             head,
             path,
             payload,
             rmap,
             config,
-            app_data,
+            app_data: data,
             pool,
         }))
     }
@@ -215,11 +219,13 @@ impl HttpRequest {
     /// let opt_t = req.app_data::<Data<T>>();
     /// ```
     pub fn app_data<T: 'static>(&self) -> Option<&T> {
-        if let Some(st) = self.0.app_data.get::<T>() {
+        for container in self.0.app_data.iter().rev() {
-            Some(&st)
+            if let Some(data) = container.get::<T>() {
-        } else {
+                return Some(data);
-            None
+            }
         }
+
+        None
     }
 }
 
@@ -342,10 +348,13 @@ impl HttpRequestPool {
 
 #[cfg(test)]
 mod tests {
+    use actix_service::Service;
+    use bytes::Bytes;
+
     use super::*;
     use crate::dev::{ResourceDef, ResourceMap};
     use crate::http::{header, StatusCode};
-    use crate::test::{call_service, init_service, TestRequest};
+    use crate::test::{call_service, init_service, read_body, TestRequest};
     use crate::{web, App, HttpResponse};
 
     #[test]
@@ -494,6 +503,68 @@ mod tests {
         assert_eq!(resp.status(), StatusCode::BAD_REQUEST);
     }
 
+    #[actix_rt::test]
+    async fn test_cascading_data() {
+        #[allow(dead_code)]
+        fn echo_usize(req: HttpRequest) -> HttpResponse {
+            let num = req.app_data::<usize>().unwrap();
+            HttpResponse::Ok().body(num.to_string())
+        }
+
+        let mut srv = init_service(
+            App::new()
+                .app_data(88usize)
+                .service(web::resource("/").route(web::get().to(echo_usize)))
+                .service(
+                    web::resource("/one")
+                        .app_data(1u32)
+                        .route(web::get().to(echo_usize)),
+                ),
+        )
+        .await;
+
+        let req = TestRequest::get().uri("/").to_request();
+        let resp = srv.call(req).await.unwrap();
+        let body = read_body(resp).await;
+        assert_eq!(body, Bytes::from_static(b"88"));
+
+        let req = TestRequest::get().uri("/one").to_request();
+        let resp = srv.call(req).await.unwrap();
+        let body = read_body(resp).await;
+        assert_eq!(body, Bytes::from_static(b"88"));
+    }
+
+    #[actix_rt::test]
+    async fn test_overwrite_data() {
+        #[allow(dead_code)]
+        fn echo_usize(req: HttpRequest) -> HttpResponse {
+            let num = req.app_data::<usize>().unwrap();
+            HttpResponse::Ok().body(num.to_string())
+        }
+
+        let mut srv = init_service(
+            App::new()
+                .app_data(88usize)
+                .service(web::resource("/").route(web::get().to(echo_usize)))
+                .service(
+                    web::resource("/one")
+                        .app_data(1usize)
+                        .route(web::get().to(echo_usize)),
+                ),
+        )
+        .await;
+
+        let req = TestRequest::get().uri("/").to_request();
+        let resp = srv.call(req).await.unwrap();
+        let body = read_body(resp).await;
+        assert_eq!(body, Bytes::from_static(b"88"));
+
+        let req = TestRequest::get().uri("/one").to_request();
+        let resp = srv.call(req).await.unwrap();
+        let body = read_body(resp).await;
+        assert_eq!(body, Bytes::from_static(b"1"));
+    }
+
     #[actix_rt::test]
     async fn test_extensions_dropped() {
         struct Tracker {

src/resource.rs

@@ -198,9 +198,7 @@ where
 
     /// Add resource data.
     ///
-    /// If used, this method will create a new data context used for extracting
+    /// Data of different types from parent contexts will still be accessible.
-    /// from requests. Data added here is *not* merged with data added on App 
-    /// or containing scopes.
     pub fn app_data<U: 'static>(mut self, data: U) -> Self {
         if self.data.is_none() {
             self.data = Some(Extensions::new());
@@ -539,14 +537,14 @@ impl Service for ResourceService {
         for route in self.routes.iter_mut() {
             if route.check(&mut req) {
                 if let Some(ref data) = self.data {
-                    req.set_data_container(data.clone());
+                    req.add_data_container(data.clone());
                 }
                 return Either::Right(route.call(req));
             }
         }
         if let Some(ref mut default) = self.default {
             if let Some(ref data) = self.data {
-                req.set_data_container(data.clone());
+                req.add_data_container(data.clone());
             }
             Either::Right(default.call(req))
         } else {
@@ -590,14 +588,13 @@ mod tests {
 
     use actix_rt::time::delay_for;
     use actix_service::Service;
-    use bytes::Bytes;
     use futures::future::ok;
 
     use crate::http::{header, HeaderValue, Method, StatusCode};
     use crate::middleware::DefaultHeaders;
     use crate::service::ServiceRequest;
-    use crate::test::{call_service, init_service, read_body, TestRequest};
+    use crate::test::{call_service, init_service, TestRequest};
-    use crate::{guard, web, App, Error, HttpRequest, HttpResponse};
+    use crate::{guard, web, App, Error, HttpResponse};
 
     #[actix_rt::test]
     async fn test_middleware() {
@@ -623,79 +620,6 @@ mod tests {
         );
     }
 
-    #[actix_rt::test]
-    async fn test_overwritten_data() {
-        #[allow(dead_code)]
-        fn echo_usize(req: HttpRequest) -> HttpResponse {
-            let num = req.app_data::<usize>().unwrap();
-            HttpResponse::Ok().body(format!("{}", num))
-        }
-
-        #[allow(dead_code)]
-        fn echo_u32(req: HttpRequest) -> HttpResponse {
-            let num = req.app_data::<u32>().unwrap();
-            HttpResponse::Ok().body(format!("{}", num))
-        }
-
-        #[allow(dead_code)]
-        fn echo_both(req: HttpRequest) -> HttpResponse {
-            let num = req.app_data::<usize>().unwrap();
-            let num2 = req.app_data::<u32>().unwrap();
-            HttpResponse::Ok().body(format!("{}-{}", num, num2))
-        }
-
-        let mut srv = init_service(
-            App::new()
-                .app_data(88usize)
-                .service(web::resource("/").route(web::get().to(echo_usize)))
-                .service(
-                    web::resource("/one")
-                        .app_data(1usize)
-                        .route(web::get().to(echo_usize)),
-                )
-                .service(
-                    web::resource("/two")
-                        .app_data(2usize)
-                        .route(web::get().to(echo_usize)),
-                )
-                .service(
-                    web::resource("/three")
-                        .app_data(3u32)
-                        // this doesnt work because app_data "overrides" the
-                        // entire data field potentially passed down
-                        // .route(web::get().to(echo_both)),
-                        .route(web::get().to(echo_u32)),
-                )
-                .service(web::resource("/eight").route(web::get().to(echo_usize))),
-        )
-        .await;
-
-        let req = TestRequest::get().uri("/").to_request();
-        let resp = srv.call(req).await.unwrap();
-        let body = read_body(resp).await;
-        assert_eq!(body, Bytes::from_static(b"88"));
-
-        let req = TestRequest::get().uri("/one").to_request();
-        let resp = srv.call(req).await.unwrap();
-        let body = read_body(resp).await;
-        assert_eq!(body, Bytes::from_static(b"1"));
-
-        let req = TestRequest::get().uri("/two").to_request();
-        let resp = srv.call(req).await.unwrap();
-        let body = read_body(resp).await;
-        assert_eq!(body, Bytes::from_static(b"2"));
-
-        // let req = TestRequest::get().uri("/three").to_request();
-        // let resp = srv.call(req).await.unwrap();
-        // let body = read_body(resp).await;
-        // assert_eq!(body, Bytes::from_static(b"88-3"));
-
-        let req = TestRequest::get().uri("/eight").to_request();
-        let resp = srv.call(req).await.unwrap();
-        let body = read_body(resp).await;
-        assert_eq!(body, Bytes::from_static(b"88"));
-    }
-
     #[actix_rt::test]
     async fn test_middleware_fn() {
         let mut srv = init_service(

src/scope.rs

@@ -153,9 +153,7 @@ where
 
     /// Add scope data.
     ///
-    /// If used, this method will create a new data context used for extracting
+    /// Data of different types from parent contexts will still be accessible.
-    /// from requests. Data added here is *not* merged with data added on App
-    /// or containing scopes.
     pub fn app_data<U: 'static>(mut self, data: U) -> Self {
         if self.data.is_none() {
             self.data = Some(Extensions::new());
@@ -624,12 +622,12 @@ impl Service for ScopeService {
 
         if let Some((srv, _info)) = res {
             if let Some(ref data) = self.data {
-                req.set_data_container(data.clone());
+                req.add_data_container(data.clone());
             }
             Either::Left(srv.call(req))
         } else if let Some(ref mut default) = self.default {
             if let Some(ref data) = self.data {
-                req.set_data_container(data.clone());
+                req.add_data_container(data.clone());
             }
             Either::Left(default.call(req))
         } else {

src/service.rs

@@ -217,11 +217,13 @@ impl ServiceRequest {
     /// Get an application data stored with `App::data()` method during
     /// application configuration.
     pub fn app_data<T: 'static>(&self) -> Option<Data<T>> {
-        if let Some(st) = (self.0).0.app_data.get::<Data<T>>() {
+        for container in (self.0).0.app_data.iter().rev() {
-            Some(st.clone())
+            if let Some(data) = container.get::<Data<T>>() {
-        } else {
+                return Some(Data::clone(&data));
-            None
+            }
         }
+
+        None
     }
 
     /// Set request payload.
@@ -230,9 +232,12 @@ impl ServiceRequest {
     }
 
     #[doc(hidden)]
-    /// Set new app data container
+    /// Add app data container to request's resolution set.
-    pub fn set_data_container(&mut self, extensions: Rc<Extensions>) {
+    pub fn add_data_container(&mut self, extensions: Rc<Extensions>) {
-        Rc::get_mut(&mut (self.0).0).unwrap().app_data = extensions;
+        Rc::get_mut(&mut (self.0).0)
+            .unwrap()
+            .app_data
+            .push(extensions);
     }
 }
 
@@ -578,7 +583,6 @@ mod tests {
         let resp = srv.call(req).await.unwrap();
         assert_eq!(resp.status(), http::StatusCode::NOT_FOUND);
     }
-
     #[test]
     fn test_fmt_debug() {
         let req = TestRequest::get()