feat: default to charset=utf-8 for text content type (#554)

* feat: default to charset=utf-8 for text content type

* added changelog && fix comment

* fix workflow

axum-extra/Cargo.toml

@@ -15,6 +15,7 @@ erased-json = ["serde", "serde_json"]
 
 [dependencies]
 axum = { path = "../axum", version = "0.3" }
+mime = "0.3"
 tower-service = "0.3"
 
 # optional dependencies

axum-extra/src/response/erased_json.rs

@@ -45,23 +45,22 @@ impl IntoResponse for ErasedJson {
     type BodyError = Infallible;
 
     fn into_response(self) -> Response<Self::Body> {
-        #[allow(clippy::declare_interior_mutable_const)]
-        const APPLICATION_JSON: HeaderValue = HeaderValue::from_static("application/json");
-
         let bytes = match self.0 {
             Ok(res) => res,
             Err(err) => {
                 return Response::builder()
                     .status(StatusCode::INTERNAL_SERVER_ERROR)
-                    .header(header::CONTENT_TYPE, "text/plain")
+                    .header(header::CONTENT_TYPE, mime::TEXT_PLAIN_UTF_8.as_ref())
                     .body(Full::from(err.to_string()))
                     .unwrap();
             }
         };
 
         let mut res = Response::new(Full::from(bytes));
-        res.headers_mut()
+        res.headers_mut().insert(
-            .insert(header::CONTENT_TYPE, APPLICATION_JSON);
+            header::CONTENT_TYPE,
+            HeaderValue::from_static(mime::APPLICATION_JSON.as_ref()),
+        );
         res
     }
 }

axum/CHANGELOG.md

@@ -33,11 +33,13 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - **breaking:** `Router::nest` will panic if the nested router has a fallback.
   Previously it would be silently discarded ([#529])
 - Update WebSockets to use tokio-tungstenite 0.16 ([#525])
+- **added:** Default to return `charset=utf-8` for text content type. ([#554])
 
 [#525]: https://github.com/tokio-rs/axum/pull/525
 [#527]: https://github.com/tokio-rs/axum/pull/527
 [#529]: https://github.com/tokio-rs/axum/pull/529
 [#534]: https://github.com/tokio-rs/axum/pull/534
+[#554]: https://github.com/tokio-rs/axum/pull/554
 
 # 0.3.3 (13. November, 2021)
 

axum/Cargo.toml

@@ -14,8 +14,8 @@ repository = "https://github.com/tokio-rs/axum"
 default = ["http1", "json", "tower-log"]
 http1 = ["hyper/http1"]
 http2 = ["hyper/http2"]
-json = ["serde_json", "mime"]
+json = ["serde_json"]
-multipart = ["multer", "mime"]
+multipart = ["multer"]
 tower-log = ["tower/log"]
 ws = ["tokio-tungstenite", "sha-1", "base64"]
 
@@ -26,6 +26,7 @@ bytes = "1.0"
 futures-util = { version = "0.3", default-features = false, features = ["alloc"] }
 http = "0.2.5"
 http-body = "0.4.4"
+mime = "0.3.16"
 hyper = { version = "0.14.14", features = ["server", "tcp", "stream"] }
 matchit = "0.4.4"
 percent-encoding = "2.1"
@@ -43,7 +44,6 @@ tower-service = "0.3"
 # optional dependencies
 base64 = { optional = true, version = "0.13" }
 headers = { optional = true, version = "0.3" }
-mime = { optional = true, version = "0.3" }
 multer = { optional = true, version = "2.0.0" }
 serde_json = { version = "1.0", optional = true, features = ["raw_value"] }
 sha-1 = { optional = true, version = "0.9.6" }

axum/src/docs/response.md

@@ -21,7 +21,7 @@ async fn plain_text() -> &'static str {
     "foo"
 }
 
-// String works too and will get a `text/plain` content-type
+// String works too and will get a `text/plain; charset=utf-8` content-type
 async fn plain_text_string(uri: Uri) -> String {
     format!("Hi from {}", uri.path())
 }

axum/src/extract/form.rs

@@ -60,7 +60,7 @@ where
                 .map_err(FailedToDeserializeQueryString::new::<T, _>)?;
             Ok(Form(value))
         } else {
-            if !has_content_type(req, "application/x-www-form-urlencoded")? {
+            if !has_content_type(req, &mime::APPLICATION_WWW_FORM_URLENCODED)? {
                 return Err(InvalidFormContentType.into());
             }
 
@@ -115,7 +115,7 @@ mod tests {
                 .method(Method::POST)
                 .header(
                     http::header::CONTENT_TYPE,
-                    "application/x-www-form-urlencoded",
+                    mime::APPLICATION_WWW_FORM_URLENCODED.as_ref(),
                 )
                 .body(http_body::Full::<bytes::Bytes>::new(
                     serde_urlencoded::to_string(&value).unwrap().into(),
@@ -182,7 +182,7 @@ mod tests {
             Request::builder()
                 .uri("http://example.com/test")
                 .method(Method::POST)
-                .header(http::header::CONTENT_TYPE, "application/json")
+                .header(http::header::CONTENT_TYPE, mime::APPLICATION_JSON.as_ref())
                 .body(http_body::Full::<bytes::Bytes>::new(
                     serde_urlencoded::to_string(&Pagination {
                         size: Some(10),

axum/src/extract/mod.rs

@@ -332,7 +332,7 @@ where
 
 pub(crate) fn has_content_type<B>(
     req: &RequestParts<B>,
-    expected_content_type: &str,
+    expected_content_type: &mime::Mime,
 ) -> Result<bool, HeadersAlreadyExtracted> {
     let content_type = if let Some(content_type) = req
         .headers()
@@ -350,7 +350,7 @@ pub(crate) fn has_content_type<B>(
         return Ok(false);
     };
 
-    Ok(content_type.starts_with(expected_content_type))
+    Ok(content_type.starts_with(expected_content_type.as_ref()))
 }
 
 pub(crate) fn take_body<B>(req: &mut RequestParts<B>) -> Result<B, BodyAlreadyExtracted> {

axum/src/json.rs

@@ -176,23 +176,25 @@ where
     type BodyError = Infallible;
 
     fn into_response(self) -> Response<Self::Body> {
-        #[allow(clippy::declare_interior_mutable_const)]
-        const APPLICATION_JSON: HeaderValue = HeaderValue::from_static("application/json");
-
         let bytes = match serde_json::to_vec(&self.0) {
             Ok(res) => res,
             Err(err) => {
                 return Response::builder()
                     .status(StatusCode::INTERNAL_SERVER_ERROR)
-                    .header(header::CONTENT_TYPE, "text/plain")
+                    .header(
+                        header::CONTENT_TYPE,
+                        HeaderValue::from_static(mime::TEXT_PLAIN_UTF_8.as_ref()),
+                    )
                     .body(Full::from(err.to_string()))
                     .unwrap();
             }
         };
 
         let mut res = Response::new(Full::from(bytes));
-        res.headers_mut()
+        res.headers_mut().insert(
-            .insert(header::CONTENT_TYPE, APPLICATION_JSON);
+            header::CONTENT_TYPE,
+            HeaderValue::from_static(mime::APPLICATION_JSON.as_ref()),
+        );
         res
     }
 }

axum/src/lib.rs

@@ -127,7 +127,7 @@
 //! };
 //! use serde_json::{Value, json};
 //!
-//! // `&'static str` becomes a `200 OK` with `content-type: text/plain`
+//! // `&'static str` becomes a `200 OK` with `content-type: text/plain; charset=utf-8`
 //! async fn plain_text() -> &'static str {
 //!     "foo"
 //! }

axum/src/response/mod.rs

@@ -331,26 +331,25 @@ impl IntoResponse for std::borrow::Cow<'static, str> {
     type BodyError = Infallible;
 
     fn into_response(self) -> Response<Self::Body> {
-        #[allow(clippy::declare_interior_mutable_const)]
-        const TEXT_PLAIN: HeaderValue = HeaderValue::from_static("text/plain");
-
         let mut res = Response::new(Full::from(self));
-        res.headers_mut().insert(header::CONTENT_TYPE, TEXT_PLAIN);
+        res.headers_mut().insert(
+            header::CONTENT_TYPE,
+            HeaderValue::from_static(mime::TEXT_PLAIN_UTF_8.as_ref()),
+        );
         res
     }
 }
 
-#[allow(clippy::declare_interior_mutable_const)]
-const APPLICATION_OCTET_STREAM: HeaderValue = HeaderValue::from_static("application/octet-stream");
-
 impl IntoResponse for Bytes {
     type Body = Full<Bytes>;
     type BodyError = Infallible;
 
     fn into_response(self) -> Response<Self::Body> {
         let mut res = Response::new(Full::from(self));
-        res.headers_mut()
+        res.headers_mut().insert(
-            .insert(header::CONTENT_TYPE, APPLICATION_OCTET_STREAM);
+            header::CONTENT_TYPE,
+            HeaderValue::from_static(mime::APPLICATION_OCTET_STREAM.as_ref()),
+        );
         res
     }
 }
@@ -361,8 +360,10 @@ impl IntoResponse for &'static [u8] {
 
     fn into_response(self) -> Response<Self::Body> {
         let mut res = Response::new(Full::from(self));
-        res.headers_mut()
+        res.headers_mut().insert(
-            .insert(header::CONTENT_TYPE, APPLICATION_OCTET_STREAM);
+            header::CONTENT_TYPE,
+            HeaderValue::from_static(mime::APPLICATION_OCTET_STREAM.as_ref()),
+        );
         res
     }
 }
@@ -373,8 +374,10 @@ impl IntoResponse for Vec<u8> {
 
     fn into_response(self) -> Response<Self::Body> {
         let mut res = Response::new(Full::from(self));
-        res.headers_mut()
+        res.headers_mut().insert(
-            .insert(header::CONTENT_TYPE, APPLICATION_OCTET_STREAM);
+            header::CONTENT_TYPE,
+            HeaderValue::from_static(mime::APPLICATION_OCTET_STREAM.as_ref()),
+        );
         res
     }
 }
@@ -385,8 +388,10 @@ impl IntoResponse for std::borrow::Cow<'static, [u8]> {
 
     fn into_response(self) -> Response<Self::Body> {
         let mut res = Response::new(Full::from(self));
-        res.headers_mut()
+        res.headers_mut().insert(
-            .insert(header::CONTENT_TYPE, APPLICATION_OCTET_STREAM);
+            header::CONTENT_TYPE,
+            HeaderValue::from_static(mime::APPLICATION_OCTET_STREAM.as_ref()),
+        );
         res
     }
 }
@@ -468,11 +473,11 @@ where
     type BodyError = Infallible;
 
     fn into_response(self) -> Response<Self::Body> {
-        #[allow(clippy::declare_interior_mutable_const)]
-        const TEXT_HTML: HeaderValue = HeaderValue::from_static("text/html");
-
         let mut res = Response::new(self.0.into());
-        res.headers_mut().insert(header::CONTENT_TYPE, TEXT_HTML);
+        res.headers_mut().insert(
+            header::CONTENT_TYPE,
+            HeaderValue::from_static(mime::TEXT_HTML_UTF_8.as_ref()),
+        );
         res
     }
 }

axum/src/response/sse.rs

@@ -104,7 +104,7 @@ where
         };
 
         Response::builder()
-            .header(http::header::CONTENT_TYPE, "text/event-stream")
+            .header(http::header::CONTENT_TYPE, mime::TEXT_EVENT_STREAM.as_ref())
             .header(http::header::CACHE_CONTROL, "no-cache")
             .body(body)
             .unwrap()

examples/testing/Cargo.toml

@@ -6,9 +6,10 @@ publish = false
 
 [dependencies]
 axum = { path = "../../axum" }
+mime = "0.3"
 tokio = { version = "1.0", features = ["full"] }
 tracing = "0.1"
-tracing-subscriber = { version="0.3", features = ["env-filter"] }
+tracing-subscriber = { version = "0.3", features = ["env-filter"] }
 tower-http = { version = "0.1", features = ["trace"] }
 serde_json = "1.0"
 hyper = { version = "0.14", features = ["full"] }

examples/testing/src/main.rs

@@ -81,7 +81,7 @@ mod tests {
                 Request::builder()
                     .method(http::Method::POST)
                     .uri("/json")
-                    .header(http::header::CONTENT_TYPE, "application/json")
+                    .header(http::header::CONTENT_TYPE, mime::APPLICATION_JSON.as_ref())
                     .body(Body::from(
                         serde_json::to_vec(&json!([1, 2, 3, 4])).unwrap(),
                     ))