From c410fdc82f747c24555c0e9f39f942720c0e6204 Mon Sep 17 00:00:00 2001
From: Charlotte Van Petegem <charlotte@vanpetegem.me>
Date: Wed, 8 Nov 2023 22:36:32 +0100
Subject: [PATCH] Make sure that content-length header can never be deleted

Once the response is `commit`ted, the headers can't be edited anymore, which is
exactly what we want in this case.
---
 app/controllers/tracks_controller.rb | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/app/controllers/tracks_controller.rb b/app/controllers/tracks_controller.rb
index a54184b3..945ee087 100644
--- a/app/controllers/tracks_controller.rb
+++ b/app/controllers/tracks_controller.rb
@@ -116,6 +116,10 @@ def audio_with_stream(stream, mimetype, total_size)
     response.content_type = mimetype
     response.headers['accept-ranges'] = 'bytes'
     response.headers['content-length'] = (last_byte - first_byte + 1).to_s
+    # Unfortunately, if we don't commit the headers, ActionController::Live will
+    # delete the "content-length" header set above. No other headers need to be
+    # set, so we just freeze them here.
+    response.commit!
 
     to_skip = first_byte
     while to_skip.positive?