From e426f3e8e1bfea5720c32d30a3663303200ee6ad Mon Sep 17 00:00:00 2001
From: Damien Arrachequesne <damien.arrachequesne@gmail.com>
Date: Mon, 12 Feb 2024 18:05:04 +0100
Subject: [PATCH] fix: remove duplicate pipeline when serving bundle

Related: https://github.com/socketio/socket.io/issues/4946
---
 lib/index.ts              |  1 -
 test/server-attachment.ts | 15 +++++++++++++++
 2 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/lib/index.ts b/lib/index.ts
index 48497e3352..bd77218318 100644
--- a/lib/index.ts
+++ b/lib/index.ts
@@ -625,7 +625,6 @@ export class Server<
     switch (encoding) {
       case "br":
         res.writeHead(200, { "content-encoding": "br" });
-        readStream.pipe(createBrotliCompress()).pipe(res);
         pipeline(readStream, createBrotliCompress(), res, onError);
         break;
       case "gzip":
diff --git a/test/server-attachment.ts b/test/server-attachment.ts
index 98d005a3d9..81da1acbcd 100644
--- a/test/server-attachment.ts
+++ b/test/server-attachment.ts
@@ -70,6 +70,21 @@ describe("server attachment", () => {
         });
     });
 
+    it("should serve client (br)", (done) => {
+      const srv = createServer();
+      new Server(srv);
+      request(srv)
+        .get("/socket.io/socket.io.js")
+        .set("accept-encoding", "br")
+        .buffer(true)
+        .end((err, res) => {
+          if (err) return done(err);
+          expect(res.headers["content-encoding"]).to.be("br");
+          expect(res.status).to.be(200);
+          done();
+        });
+    });
+
     it("should serve client with necessary CORS headers", (done) => {
       const srv = createServer();
       new Server(srv, {