recover from malformed location header when redirecting

based on code from #2111
closes #2102

awc/src/lib.rs

@@ -1,22 +1,25 @@
 //! `awc` is an asynchronous HTTP and WebSocket client library.
 //!
-//! # Making a GET request
+//! # `GET` Requests
 //! ```no_run
 //! # #[actix_rt::main]
 //! # async fn main() -> Result<(), awc::error::SendRequestError> {
+//! // create client
 //! let mut client = awc::Client::default();
-//! let response = client.get("http://www.rust-lang.org") // <- Create request builder
-//!     .insert_header(("User-Agent", "Actix-web"))
-//!     .send()                                            // <- Send http request
-//!     .await?;
 //!
-//!  println!("Response: {:?}", response);
+//! // construct request
+//! let req = client.get("http://www.rust-lang.org")
+//!     .insert_header(("User-Agent", "awc/3.0"));
+//!
+//! // send request and await response
+//! let res = req.send().await?;
+//! println!("Response: {:?}", res);
 //! # Ok(())
 //! # }
 //! ```
 //!
-//! # Making POST requests
+//! # `POST` Requests
-//! ## Raw body contents
+//! ## Raw Body
 //! ```no_run
 //! # #[actix_rt::main]
 //! # async fn main() -> Result<(), awc::error::SendRequestError> {
@@ -28,20 +31,6 @@
 //! # }
 //! ```
 //!
-//! ## Forms
-//! ```no_run
-//! # #[actix_rt::main]
-//! # async fn main() -> Result<(), awc::error::SendRequestError> {
-//! let params = [("foo", "bar"), ("baz", "quux")];
-//!
-//! let mut client = awc::Client::default();
-//! let response = client.post("http://httpbin.org/post")
-//!     .send_form(&params)
-//!     .await?;
-//! # Ok(())
-//! # }
-//! ```
-//!
 //! ## JSON
 //! ```no_run
 //! # #[actix_rt::main]
@@ -59,6 +48,20 @@
 //! # }
 //! ```
 //!
+//! ## URL Encoded Form
+//! ```no_run
+//! # #[actix_rt::main]
+//! # async fn main() -> Result<(), awc::error::SendRequestError> {
+//! let params = [("foo", "bar"), ("baz", "quux")];
+//!
+//! let mut client = awc::Client::default();
+//! let response = client.post("http://httpbin.org/post")
+//!     .send_form(&params)
+//!     .await?;
+//! # Ok(())
+//! # }
+//! ```
+//!
 //! # Response Compression
 //! All [official][iana-encodings] and common content encoding codecs are supported, optionally.
 //!
@@ -76,11 +79,12 @@
 //!
 //! [iana-encodings]: https://www.iana.org/assignments/http-parameters/http-parameters.xhtml#content-coding
 //!
-//! # WebSocket support
+//! # WebSockets
 //! ```no_run
 //! # #[actix_rt::main]
 //! # async fn main() -> Result<(), Box<dyn std::error::Error>> {
-//! use futures_util::{sink::SinkExt, stream::StreamExt};
+//! use futures_util::{sink::SinkExt as _, stream::StreamExt as _};
+//!
 //! let (_resp, mut connection) = awc::Client::new()
 //!     .ws("ws://echo.websocket.org")
 //!     .connect()
@@ -89,8 +93,9 @@
 //! connection
 //!     .send(awc::ws::Message::Text("Echo".into()))
 //!     .await?;
+//!
 //! let response = connection.next().await.unwrap()?;
-//! # assert_eq!(response, awc::ws::Frame::Text("Echo".as_bytes().into()));
+//! assert_eq!(response, awc::ws::Frame::Text("Echo".into()));
 //! # Ok(())
 //! # }
 //! ```

awc/src/middleware/redirect.rs

@@ -246,26 +246,32 @@ where
 }
 
 fn build_next_uri(res: &ClientResponse, prev_uri: &Uri) -> Result<Uri, SendRequestError> {
-    let uri = res
+    // responses without this header are not processed
-        .headers()
+    let location = res.headers().get(header::LOCATION).unwrap();
-        .get(header::LOCATION)
+
-        .map(|value| {
+    // try to parse the location and resolve to a full URI but fall back to default if it fails
-            // try to parse the location to a full uri
+    let uri = Uri::try_from(location.as_bytes()).unwrap_or_else(|_| Uri::default());
-            let uri = Uri::try_from(value.as_bytes())
+
-                .map_err(|e| SendRequestError::Url(InvalidUrl::HttpError(e.into())))?;
+    let uri = if uri.scheme().is_none() || uri.authority().is_none() {
-            if uri.scheme().is_none() || uri.authority().is_none() {
+        let builder = Uri::builder()
-                let uri = Uri::builder()
             .scheme(prev_uri.scheme().cloned().unwrap())
-                    .authority(prev_uri.authority().cloned().unwrap())
+            .authority(prev_uri.authority().cloned().unwrap());
-                    .path_and_query(value.as_bytes())
+
-                    .build()?;
+        // when scheme or authority is missing treat the location value as path and query
-                Ok::<_, SendRequestError>(uri)
+        // recover error where location does not have leading slash
+        let path = if location.as_bytes().starts_with(b"/") {
+            location.as_bytes().to_owned()
         } else {
-                Ok(uri)
+            [b"/", location.as_bytes()].concat()
-            }
+        };
-        })
+
-        // TODO: this error type is wrong.
+        builder
-        .ok_or(SendRequestError::Url(InvalidUrl::MissingScheme))??;
+            .path_and_query(path)
+            .build()
+            .map_err(|err| SendRequestError::Url(InvalidUrl::HttpError(err)))?
+    } else {
+        uri
+    };
 
     Ok(uri)
 }
@@ -294,7 +300,7 @@ mod tests {
     };
 
     #[actix_rt::test]
-    async fn test_basic_redirect() {
+    async fn basic_redirect() {
         let client = ClientBuilder::new()
             .disable_redirects()
             .wrap(Redirect::new().max_redirect_times(10))
@@ -319,6 +325,27 @@ mod tests {
         assert_eq!(res.status().as_u16(), 400);
     }
 
+    #[actix_rt::test]
+    async fn redirect_relative_without_leading_slash() {
+        let client = ClientBuilder::new().finish();
+
+        let srv = actix_test::start(|| {
+            App::new()
+                .service(web::resource("/").route(web::to(|| async {
+                    HttpResponse::Found()
+                        .insert_header(("location", "abc/"))
+                        .finish()
+                })))
+                .service(
+                    web::resource("/abc/")
+                        .route(web::to(|| async { HttpResponse::Accepted().finish() })),
+                )
+        });
+
+        let res = client.get(srv.url("/")).send().await.unwrap();
+        assert_eq!(res.status(), StatusCode::ACCEPTED);
+    }
+
     #[actix_rt::test]
     async fn redirect_without_location() {
         let client = ClientBuilder::new()