tower-rs · davidpdrsn · Jun 23, 2021 · May 21, 2021 · Jun 4, 2021 · Jun 4, 2021
diff --git a/tower-http/CHANGELOG.md b/tower-http/CHANGELOG.md
@@ -7,6 +7,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 # Unreleased
 
+- Add `AddAuthorizationLayer` for setting the `Authorization` header on
+  requests.
 - Add example of using `SharedClassifier`.
 - Add `StatusInRangeAsFailures` which is a response classifier that considers
   responses with status code in a certain range as failures. Useful for HTTP

diff --git a/tower-http/src/auth/add_authorization.rs b/tower-http/src/auth/add_authorization.rs
@@ -0,0 +1,262 @@
+//! Add authorization to requests using the [`Authorization`] header.
+//!
+//! [`Authorization`]: https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Authorization
+//!
+//! # Example
+//!
+//! ```
+//! use tower_http::auth::AddAuthorizationLayer;
+//! use hyper::{Request, Response, Body, Error};
+//! use http::{StatusCode, header::AUTHORIZATION};
+//! use tower::{Service, ServiceExt, ServiceBuilder, service_fn};
+//! # async fn handle(request: Request<Body>) -> Result<Response<Body>, Error> {
+//! #     Ok(Response::new(Body::empty()))
+//! # }
+//!
+//! # #[tokio::main]
+//! # async fn main() -> Result<(), Box<dyn std::error::Error>> {
+//! # let service_that_requires_auth = tower_http::auth::RequireAuthorization::basic(
+//! #     tower::service_fn(handle),
+//! #     "username",
+//! #     "password",
+//! # );
+//! let mut client = ServiceBuilder::new()
+//!     // Use basic auth with the given username and password
+//!     .layer(AddAuthorizationLayer::basic("username", "password"))
+//!     .service(service_that_requires_auth);
+//!
+//! // Make a request, we don't have to add the `Authorization` header manually
+//! let response = client
+//!     .ready()
+//!     .await?
+//!     .call(Request::new(Body::empty()))
+//!     .await?;
+//!
+//! assert_eq!(StatusCode::OK, response.status());
+//! # Ok(())
+//! # }
+//! ```
+
+use http::{HeaderValue, Request};
+use std::{
+    convert::TryFrom,
+    task::{Context, Poll},
+};
+use tower_layer::Layer;
+use tower_service::Service;
+
+/// Layer that applies [`AddAuthorization`] which adds authorization to all requests using the
+/// [`Authorization`] header.
+///
+/// See the [module docs](crate::auth::add_authorization) for an example.
+///
+/// You can also use [`SetRequestHeader`] if you have a use case that isn't supported by this
+/// middleware.
+///
+/// [`Authorization`]: https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Authorization
+/// [`SetRequestHeader`]: crate::set_header::SetRequestHeader
+#[derive(Debug, Clone)]
+pub struct AddAuthorizationLayer {
+    value: HeaderValue,
+}
+
+impl AddAuthorizationLayer {
+    /// Authorize requests using a username and password pair.
+    ///
+    /// The `Authorization` header will be set to `Basic {credentials}` where `credentials` is
+    /// `base64_encode("{username}:{password}")`.
+    ///
+    /// Since the username and password is sent in clear text it is recommended to use HTTPS/TLS
+    /// with this method. However use of HTTPS/TLS is not enforced by this middleware.
+    pub fn basic(username: &str, password: &str) -> Self {
+        let encoded = base64::encode(format!("{}:{}", username, password));
+        let value = HeaderValue::try_from(format!("Basic {}", encoded)).unwrap();
+        Self { value }
+    }
+
+    /// Authorize requests using a "bearer token". Commonly used for OAuth 2.
+    ///
+    /// The `Authorization` header will be set to `Bearer {token}`.
+    ///
+    /// # Panics
+    ///
+    /// Panics if the token is not a valid [`HeaderValue`](http::header::HeaderValue).
+    pub fn bearer(token: &str) -> Self {
+        let value =
+            HeaderValue::try_from(format!("Bearer {}", token)).expect("token is not valid header");
+        Self { value }
+    }
+
+    /// Mark the header as [sensitive].
+    ///
+    /// This can for example be used to hide the header value from logs.
+    ///
+    /// [sensitive]: https://docs.rs/http/latest/http/header/struct.HeaderValue.html#method.set_sensitive
+    #[allow(clippy::wrong_self_convention)]
+    pub fn as_sensitive(mut self, sensitive: bool) -> Self {
+        self.value.set_sensitive(sensitive);
+        self
+    }
+}
+
+impl<S> Layer<S> for AddAuthorizationLayer {
+    type Service = AddAuthorization<S>;
+
+    fn layer(&self, inner: S) -> Self::Service {
+        AddAuthorization {
+            inner,
+            value: self.value.clone(),
+        }
+    }
+}
+
+/// Middleware that adds authorization all requests using the [`Authorization`] header.
+///
+/// See the [module docs](crate::auth::add_authorization) for an example.
+///
+/// You can also use [`SetRequestHeader`] if you have a use case that isn't supported by this
+/// middleware.
+///
+/// [`Authorization`]: https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Authorization
+/// [`SetRequestHeader`]: crate::set_header::SetRequestHeader
+#[derive(Debug, Clone)]
+pub struct AddAuthorization<S> {
+    inner: S,
+    value: HeaderValue,
+}
+
+impl<S> AddAuthorization<S> {
+    /// Authorize requests using a username and password pair.
+    ///
+    /// The `Authorization` header will be set to `Basic {credentials}` where `credentials` is
+    /// `base64_encode("{username}:{password}")`.
+    ///
+    /// Since the username and password is sent in clear text it is recommended to use HTTPS/TLS
+    /// with this method. However use of HTTPS/TLS is not enforced by this middleware.
+    pub fn basic(inner: S, username: &str, password: &str) -> Self {
+        AddAuthorizationLayer::basic(username, password).layer(inner)
+    }
+
+    /// Authorize requests using a "bearer token". Commonly used for OAuth 2.
+    ///
+    /// The `Authorization` header will be set to `Bearer {token}`.
+    ///
+    /// # Panics
+    ///
+    /// Panics if the token is not a valid [`HeaderValue`](http::header::HeaderValue).
+    pub fn bearer(inner: S, token: &str) -> Self {
+        AddAuthorizationLayer::bearer(token).layer(inner)
+    }
+
+    define_inner_service_accessors!();
+
+    /// Mark the header as [sensitive].
+    ///
+    /// This can for example be used to hide the header value from logs.
+    ///
+    /// [sensitive]: https://docs.rs/http/latest/http/header/struct.HeaderValue.html#method.set_sensitive
+    #[allow(clippy::wrong_self_convention)]
+    pub fn as_sensitive(mut self, sensitive: bool) -> Self {
+        self.value.set_sensitive(sensitive);
+        self
+    }
+}
+
+impl<S, ReqBody> Service<Request<ReqBody>> for AddAuthorization<S>
+where
+    S: Service<Request<ReqBody>>,
+{
+    type Response = S::Response;
+    type Error = S::Error;
+    type Future = S::Future;
+
+    fn poll_ready(&mut self, cx: &mut Context<'_>) -> Poll<Result<(), Self::Error>> {
+        self.inner.poll_ready(cx)
+    }
+
+    fn call(&mut self, mut req: Request<ReqBody>) -> Self::Future {
+        req.headers_mut()
+            .insert(http::header::AUTHORIZATION, self.value.clone());
+        self.inner.call(req)
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    #[allow(unused_imports)]
+    use super::*;
+    use crate::auth::RequireAuthorizationLayer;
+    use http::{Response, StatusCode};
+    use hyper::Body;
+    use tower::{BoxError, Service, ServiceBuilder, ServiceExt};
+
+    #[tokio::test]
+    async fn basic() {
+        // service that requires auth for all requests
+        let svc = ServiceBuilder::new()
+            .layer(RequireAuthorizationLayer::basic("foo", "bar"))
+            .service_fn(echo);
+
+        // make a client that adds auth
+        let mut client = AddAuthorization::basic(svc, "foo", "bar");
+
+        let res = client
+            .ready()
+            .await
+            .unwrap()
+            .call(Request::new(Body::empty()))
+            .await
+            .unwrap();
+
+        assert_eq!(res.status(), StatusCode::OK);
+    }
+
+    #[tokio::test]
+    async fn token() {
+        // service that requires auth for all requests
+        let svc = ServiceBuilder::new()
+            .layer(RequireAuthorizationLayer::bearer("foo"))
+            .service_fn(echo);
+
+        // make a client that adds auth
+        let mut client = AddAuthorization::bearer(svc, "foo");
+
+        let res = client
+            .ready()
+            .await
+            .unwrap()
+            .call(Request::new(Body::empty()))
+            .await
+            .unwrap();
+
+        assert_eq!(res.status(), StatusCode::OK);
+    }
+
+    #[tokio::test]
+    async fn making_header_sensitive() {
+        let svc = ServiceBuilder::new()
+            .layer(RequireAuthorizationLayer::bearer("foo"))
+            .service_fn(|request: Request<Body>| async move {
+                let auth = request.headers().get(http::header::AUTHORIZATION).unwrap();
+                assert!(auth.is_sensitive());
+
+                Ok::<_, hyper::Error>(Response::new(Body::empty()))
+            });
+
+        let mut client = AddAuthorization::bearer(svc, "foo").as_sensitive(true);
+
+        let res = client
+            .ready()
+            .await
+            .unwrap()
+            .call(Request::new(Body::empty()))
+            .await
+            .unwrap();
+
+        assert_eq!(res.status(), StatusCode::OK);
+    }
+
+    async fn echo(req: Request<Body>) -> Result<Response<Body>, BoxError> {
+        Ok(Response::new(req.into_body()))
+    }
+}
diff --git a/tower-http/src/auth/mod.rs b/tower-http/src/auth/mod.rs
@@ -1,8 +1,10 @@
 //! Authorization related middleware.
 
+pub mod add_authorization;
 pub mod require_authorization;
 
 #[doc(inline)]
-pub use self::require_authorization::{
-    AuthorizeRequest, RequireAuthorization, RequireAuthorizationLayer,
+pub use self::{
+    add_authorization::{AddAuthorization, AddAuthorizationLayer},
+    require_authorization::{AuthorizeRequest, RequireAuthorization, RequireAuthorizationLayer},
 };
diff --git a/tower-http/src/auth/require_authorization.rs b/tower-http/src/auth/require_authorization.rs
@@ -28,7 +28,7 @@
 //!     .unwrap();
 //!
 //! let response = service
-//!     .ready_and()
+//!     .ready()
 //!     .await?
 //!     .call(request)
 //!     .await?;
@@ -41,7 +41,7 @@
 //!     .unwrap();
 //!
 //! let response = service
-//!     .ready_and()
+//!     .ready()
 //!     .await?
 //!     .call(request)
 //!     .await?;