From 845c02cb86f3ce5ff210a530855d86e1b5471c60 Mon Sep 17 00:00:00 2001
From: fakeshadow <24548779@qq.com>
Date: Thu, 15 Apr 2021 16:54:51 -0700
Subject: [PATCH] Add responder impl for Cow<str> (#2164)

---
 actix-http/src/body/body.rs | 16 ++++++-
 src/responder.rs            | 85 +++++++++++++++++++------------------
 2 files changed, 57 insertions(+), 44 deletions(-)

diff --git a/actix-http/src/body/body.rs b/actix-http/src/body/body.rs
index 5fc461d41..4fe18338a 100644
--- a/actix-http/src/body/body.rs
+++ b/actix-http/src/body/body.rs
@@ -1,4 +1,5 @@
 use std::{
+    borrow::Cow,
     fmt, mem,
     pin::Pin,
     task::{Context, Poll},
@@ -118,12 +119,23 @@ impl From<String> for Body {
     }
 }
 
-impl<'a> From<&'a String> for Body {
-    fn from(s: &'a String) -> Body {
+impl From<&'_ String> for Body {
+    fn from(s: &String) -> Body {
         Body::Bytes(Bytes::copy_from_slice(AsRef::<[u8]>::as_ref(&s)))
     }
 }
 
+impl From<Cow<'_, str>> for Body {
+    fn from(s: Cow<'_, str>) -> Body {
+        match s {
+            Cow::Owned(s) => Body::from(s),
+            Cow::Borrowed(s) => {
+                Body::Bytes(Bytes::copy_from_slice(AsRef::<[u8]>::as_ref(s)))
+            }
+        }
+    }
+}
+
 impl From<Bytes> for Body {
     fn from(s: Bytes) -> Body {
         Body::Bytes(s)
diff --git a/src/responder.rs b/src/responder.rs
index 2348e9276..7b8288ed8 100644
--- a/src/responder.rs
+++ b/src/responder.rs
@@ -1,4 +1,4 @@
-use std::fmt;
+use std::{borrow::Cow, fmt};
 
 use actix_http::{
     body::Body,
@@ -117,53 +117,29 @@ impl<T: Responder> Responder for (T, StatusCode) {
     }
 }
 
-impl Responder for &'static str {
-    fn respond_to(self, _: &HttpRequest) -> HttpResponse {
-        HttpResponse::Ok()
-            .content_type(mime::TEXT_PLAIN_UTF_8)
-            .body(self)
-    }
+macro_rules! impl_responder {
+    ($res: ty, $ct: path) => {
+        impl Responder for $res {
+            fn respond_to(self, _: &HttpRequest) -> HttpResponse {
+                HttpResponse::Ok().content_type($ct).body(self)
+            }
+        }
+    };
 }
 
-impl Responder for &'static [u8] {
-    fn respond_to(self, _: &HttpRequest) -> HttpResponse {
-        HttpResponse::Ok()
-            .content_type(mime::APPLICATION_OCTET_STREAM)
-            .body(self)
-    }
-}
+impl_responder!(&'static str, mime::TEXT_PLAIN_UTF_8);
 
-impl Responder for String {
-    fn respond_to(self, _: &HttpRequest) -> HttpResponse {
-        HttpResponse::Ok()
-            .content_type(mime::TEXT_PLAIN_UTF_8)
-            .body(self)
-    }
-}
+impl_responder!(String, mime::TEXT_PLAIN_UTF_8);
 
-impl<'a> Responder for &'a String {
-    fn respond_to(self, _: &HttpRequest) -> HttpResponse {
-        HttpResponse::Ok()
-            .content_type(mime::TEXT_PLAIN_UTF_8)
-            .body(self)
-    }
-}
+impl_responder!(&'_ String, mime::TEXT_PLAIN_UTF_8);
 
-impl Responder for Bytes {
-    fn respond_to(self, _: &HttpRequest) -> HttpResponse {
-        HttpResponse::Ok()
-            .content_type(mime::APPLICATION_OCTET_STREAM)
-            .body(self)
-    }
-}
+impl_responder!(Cow<'_, str>, mime::TEXT_PLAIN_UTF_8);
 
-impl Responder for BytesMut {
-    fn respond_to(self, _: &HttpRequest) -> HttpResponse {
-        HttpResponse::Ok()
-            .content_type(mime::APPLICATION_OCTET_STREAM)
-            .body(self)
-    }
-}
+impl_responder!(&'static [u8], mime::APPLICATION_OCTET_STREAM);
+
+impl_responder!(Bytes, mime::APPLICATION_OCTET_STREAM);
+
+impl_responder!(BytesMut, mime::APPLICATION_OCTET_STREAM);
 
 /// Allows overriding status code and headers for a responder.
 pub struct CustomResponder<T> {
@@ -358,6 +334,31 @@ pub(crate) mod tests {
             HeaderValue::from_static("text/plain; charset=utf-8")
         );
 
+        let s = String::from("test");
+        let resp = Cow::Borrowed(s.as_str()).respond_to(&req);
+        assert_eq!(resp.status(), StatusCode::OK);
+        assert_eq!(resp.body().bin_ref(), b"test");
+        assert_eq!(
+            resp.headers().get(CONTENT_TYPE).unwrap(),
+            HeaderValue::from_static("text/plain; charset=utf-8")
+        );
+
+        let resp = Cow::<'_, str>::Owned(s).respond_to(&req);
+        assert_eq!(resp.status(), StatusCode::OK);
+        assert_eq!(resp.body().bin_ref(), b"test");
+        assert_eq!(
+            resp.headers().get(CONTENT_TYPE).unwrap(),
+            HeaderValue::from_static("text/plain; charset=utf-8")
+        );
+
+        let resp = Cow::Borrowed("test").respond_to(&req);
+        assert_eq!(resp.status(), StatusCode::OK);
+        assert_eq!(resp.body().bin_ref(), b"test");
+        assert_eq!(
+            resp.headers().get(CONTENT_TYPE).unwrap(),
+            HeaderValue::from_static("text/plain; charset=utf-8")
+        );
+
         let resp = Bytes::from_static(b"test").respond_to(&req);
         assert_eq!(resp.status(), StatusCode::OK);
         assert_eq!(resp.body().bin_ref(), b"test");