body ergonomics v3 (#2468)

src/response/builder.rs

@@ -1,14 +1,13 @@
 use std::{
     cell::{Ref, RefMut},
     convert::TryInto,
-    error::Error as StdError,
     future::Future,
     pin::Pin,
     task::{Context, Poll},
 };
 
 use actix_http::{
-    body::{AnyBody, BodyStream},
+    body::{BodyStream, BoxBody, MessageBody},
     http::{
         header::{self, HeaderName, IntoHeaderPair, IntoHeaderValue},
         ConnectionType, Error as HttpError, StatusCode,
@@ -26,14 +25,14 @@ use cookie::{Cookie, CookieJar};
 
 use crate::{
     error::{Error, JsonPayloadError},
-    HttpResponse,
+    BoxError, HttpResponse,
 };
 
 /// An HTTP response builder.
 ///
 /// This type can be used to construct an instance of `Response` through a builder-like pattern.
 pub struct HttpResponseBuilder {
-    res: Option<Response<AnyBody>>,
+    res: Option<Response<BoxBody>>,
     err: Option<HttpError>,
     #[cfg(feature = "cookies")]
     cookies: Option<CookieJar>,
@@ -44,7 +43,7 @@ impl HttpResponseBuilder {
     /// Create response builder
     pub fn new(status: StatusCode) -> Self {
         Self {
-            res: Some(Response::new(status)),
+            res: Some(Response::with_body(status, BoxBody::new(()))),
             err: None,
             #[cfg(feature = "cookies")]
             cookies: None,
@@ -299,7 +298,6 @@ impl HttpResponseBuilder {
     }
 
     /// Mutable reference to a the response's extensions
-    #[inline]
     pub fn extensions_mut(&mut self) -> RefMut<'_, Extensions> {
         self.res
             .as_mut()
@@ -307,18 +305,20 @@ impl HttpResponseBuilder {
             .extensions_mut()
     }
 
-    /// Set a body and generate `Response`.
+    /// Set a body and build the `HttpResponse`.
     ///
     /// `HttpResponseBuilder` can not be used after this call.
-    #[inline]
-    pub fn body<B: Into<AnyBody>>(&mut self, body: B) -> HttpResponse<AnyBody> {
-        match self.message_body(body.into()) {
-            Ok(res) => res,
+    pub fn body<B>(&mut self, body: B) -> HttpResponse<BoxBody>
+    where
+        B: MessageBody + 'static,
+    {
+        match self.message_body(body) {
+            Ok(res) => res.map_into_boxed_body(),
             Err(err) => HttpResponse::from_error(err),
         }
     }
 
-    /// Set a body and generate `Response`.
+    /// Set a body and build the `HttpResponse`.
     ///
     /// `HttpResponseBuilder` can not be used after this call.
     pub fn message_body<B>(&mut self, body: B) -> Result<HttpResponse<B>, Error> {
@@ -332,7 +332,7 @@ impl HttpResponseBuilder {
             .expect("cannot reuse response builder")
             .set_body(body);
 
-        #[allow(unused_mut)]
+        #[allow(unused_mut)] // mut is only unused when cookies are disabled
         let mut res = HttpResponse::from(res);
 
         #[cfg(feature = "cookies")]
@@ -348,19 +348,19 @@ impl HttpResponseBuilder {
         Ok(res)
     }
 
-    /// Set a streaming body and generate `Response`.
+    /// Set a streaming body and build the `HttpResponse`.
     ///
     /// `HttpResponseBuilder` can not be used after this call.
     #[inline]
     pub fn streaming<S, E>(&mut self, stream: S) -> HttpResponse
     where
         S: Stream<Item = Result<Bytes, E>> + 'static,
-        E: Into<Box<dyn StdError>> + 'static,
+        E: Into<BoxError> + 'static,
     {
-        self.body(AnyBody::new_boxed(BodyStream::new(stream)))
+        self.body(BodyStream::new(stream))
     }
 
-    /// Set a json body and generate `Response`
+    /// Set a JSON body and build the `HttpResponse`.
     ///
     /// `HttpResponseBuilder` can not be used after this call.
     pub fn json(&mut self, value: impl Serialize) -> HttpResponse {
@@ -376,18 +376,18 @@ impl HttpResponseBuilder {
                     self.insert_header((header::CONTENT_TYPE, mime::APPLICATION_JSON));
                 }
 
-                self.body(AnyBody::from(body))
+                self.body(body)
             }
             Err(err) => HttpResponse::from_error(JsonPayloadError::Serialize(err)),
         }
     }
 
-    /// Set an empty body and generate `Response`
+    /// Set an empty body and build the `HttpResponse`.
     ///
     /// `HttpResponseBuilder` can not be used after this call.
     #[inline]
     pub fn finish(&mut self) -> HttpResponse {
-        self.body(AnyBody::empty())
+        self.body(())
     }
 
     /// This method construct new `HttpResponseBuilder`
@@ -416,7 +416,7 @@ impl From<HttpResponseBuilder> for HttpResponse {
     }
 }
 
-impl From<HttpResponseBuilder> for Response<AnyBody> {
+impl From<HttpResponseBuilder> for Response<BoxBody> {
     fn from(mut builder: HttpResponseBuilder) -> Self {
         builder.finish().into()
     }
@@ -435,12 +435,9 @@ mod tests {
     use actix_http::body;
 
     use super::*;
-    use crate::{
-        dev::AnyBody,
-        http::{
-            header::{self, HeaderValue, CONTENT_TYPE},
-            StatusCode,
-        },
+    use crate::http::{
+        header::{self, HeaderValue, CONTENT_TYPE},
+        StatusCode,
     };
 
     #[test]
@@ -475,7 +472,7 @@ mod tests {
     fn test_content_type() {
         let resp = HttpResponseBuilder::new(StatusCode::OK)
             .content_type("text/plain")
-            .body(AnyBody::empty());
+            .body(Bytes::new());
         assert_eq!(resp.headers().get(CONTENT_TYPE).unwrap(), "text/plain")
     }
 

src/response/response.rs

@@ -8,7 +8,7 @@ use std::{
 };
 
 use actix_http::{
-    body::{AnyBody, MessageBody},
+    body::{BoxBody, EitherBody, MessageBody},
     http::{header::HeaderMap, StatusCode},
     Extensions, Response, ResponseHead,
 };
@@ -25,12 +25,12 @@ use {
 use crate::{error::Error, HttpResponseBuilder};
 
 /// An outgoing response.
-pub struct HttpResponse<B = AnyBody> {
+pub struct HttpResponse<B = BoxBody> {
     res: Response<B>,
     pub(crate) error: Option<Error>,
 }
 
-impl HttpResponse<AnyBody> {
+impl HttpResponse<BoxBody> {
     /// Constructs a response.
     #[inline]
     pub fn new(status: StatusCode) -> Self {
@@ -227,8 +227,26 @@ impl<B> HttpResponse<B> {
         }
     }
 
-    // TODO: into_body equivalent
-    // TODO: into_boxed_body
+    // TODO: docs for the body map methods below
+
+    #[inline]
+    pub fn map_into_left_body<R>(self) -> HttpResponse<EitherBody<B, R>> {
+        self.map_body(|_, body| EitherBody::left(body))
+    }
+
+    #[inline]
+    pub fn map_into_right_body<L>(self) -> HttpResponse<EitherBody<L, B>> {
+        self.map_body(|_, body| EitherBody::right(body))
+    }
+
+    #[inline]
+    pub fn map_into_boxed_body(self) -> HttpResponse<BoxBody>
+    where
+        B: MessageBody + 'static,
+    {
+        // TODO: avoid double boxing with down-casting, if it improves perf
+        self.map_body(|_, body| BoxBody::new(body))
+    }
 
     /// Extract response body
     pub fn into_body(self) -> B {
@@ -273,14 +291,14 @@ impl<B> From<HttpResponse<B>> for Response<B> {
     }
 }
 
-// Future is only implemented for AnyBody payload type because it's the most useful for making
+// Future is only implemented for BoxBody payload type because it's the most useful for making
 // simple handlers without async blocks. Making it generic over all MessageBody types requires a
 // future impl on Response which would cause it's body field to be, undesirably, Option<B>.
 //
 // This impl is not particularly efficient due to the Response construction and should probably
 // not be invoked if performance is important. Prefer an async fn/block in such cases.
-impl Future for HttpResponse<AnyBody> {
-    type Output = Result<Response<AnyBody>, Error>;
+impl Future for HttpResponse<BoxBody> {
+    type Output = Result<Response<BoxBody>, Error>;
 
     fn poll(mut self: Pin<&mut Self>, _: &mut Context<'_>) -> Poll<Self::Output> {
         if let Some(err) = self.error.take() {