From f82f05c6c9d788e00bab17f232db10b208d36971 Mon Sep 17 00:00:00 2001
From: Amit Upadhyay <upadhyay@gmail.com>
Date: Wed, 15 Nov 2023 13:49:30 +0530
Subject: [PATCH] AcceptEncoding.{ranked,negotiate}() prefers brotli > zstd >
 gzip

---
 actix-web/src/http/header/accept_encoding.rs | 13 ++++++++++---
 actix-web/tests/compression.rs               |  8 ++++----
 2 files changed, 14 insertions(+), 7 deletions(-)

diff --git a/actix-web/src/http/header/accept_encoding.rs b/actix-web/src/http/header/accept_encoding.rs
index 2ef19320f..7116832c2 100644
--- a/actix-web/src/http/header/accept_encoding.rs
+++ b/actix-web/src/http/header/accept_encoding.rs
@@ -223,7 +223,11 @@ impl AcceptEncoding {
         // use stable sort so items with equal q-factor retain listed order
         types.sort_by(|a, b| {
             // sort by q-factor descending
-            b.quality.cmp(&a.quality)
+            if b.quality == a.quality {
+                encoding_rank(b).cmp(&encoding_rank(a))
+            } else {
+                b.quality.cmp(&a.quality)
+            }
         });
 
         types.into_iter()
@@ -393,11 +397,11 @@ mod tests {
         );
         assert_eq!(
             test.negotiate([Encoding::gzip(), Encoding::brotli(), Encoding::identity()].iter()),
-            Some(Encoding::gzip())
+            Some(Encoding::brotli())
         );
         assert_eq!(
             test.negotiate([Encoding::brotli(), Encoding::gzip(), Encoding::identity()].iter()),
-            Some(Encoding::gzip())
+            Some(Encoding::brotli())
         );
     }
 
@@ -414,6 +418,9 @@ mod tests {
 
         let test = accept_encoding!("br", "gzip", "*");
         assert_eq!(test.ranked(), vec![enc("br"), enc("gzip"), enc("*")]);
+
+        let test = accept_encoding!("gzip", "br", "*");
+        assert_eq!(test.ranked(), vec![enc("br"), enc("gzip"), enc("*")]);
     }
 
     #[test]
diff --git a/actix-web/tests/compression.rs b/actix-web/tests/compression.rs
index b911b9d1f..38a8ec34f 100644
--- a/actix-web/tests/compression.rs
+++ b/actix-web/tests/compression.rs
@@ -96,7 +96,7 @@ async fn negotiate_encoding_gzip() {
 
     let req = srv
         .post("/static")
-        .insert_header((header::ACCEPT_ENCODING, "gzip,br,zstd"))
+        .insert_header((header::ACCEPT_ENCODING, "gzip"))
         .send();
 
     let mut res = req.await.unwrap();
@@ -109,7 +109,7 @@ async fn negotiate_encoding_gzip() {
     let mut res = srv
         .post("/static")
         .no_decompress()
-        .insert_header((header::ACCEPT_ENCODING, "gzip,br,zstd"))
+        .insert_header((header::ACCEPT_ENCODING, "gzip"))
         .send()
         .await
         .unwrap();
@@ -154,7 +154,7 @@ async fn negotiate_encoding_zstd() {
 
     let req = srv
         .post("/static")
-        .insert_header((header::ACCEPT_ENCODING, "zstd,gzip,br"))
+        .insert_header((header::ACCEPT_ENCODING, "zstd,gzip"))
         .send();
 
     let mut res = req.await.unwrap();
@@ -167,7 +167,7 @@ async fn negotiate_encoding_zstd() {
     let mut res = srv
         .post("/static")
         .no_decompress()
-        .insert_header((header::ACCEPT_ENCODING, "zstd,gzip,br"))
+        .insert_header((header::ACCEPT_ENCODING, "zstd,gzip"))
         .send()
         .await
         .unwrap();