From d10b6dc498c2537a3de273e0fa213df4a9a12f0b Mon Sep 17 00:00:00 2001
From: Sam <sam.saffron@gmail.com>
Date: Thu, 29 Oct 2020 16:25:46 +1100
Subject: [PATCH] FEATURE: Allow admins to opt out of chunked encoding (#11060)

Most proxies out there will work with chunked encoding transfer. However
some proxies buffer, causing large delays which in turn force the message
bus client to disable chunked encoding. This wastes a request to the message
bus causing superfluous load on the server.

Also

- enableLongPolling is already default true in the client, no need to set it
- remove confusing comment about zepto
---
 .../javascripts/discourse/app/initializers/message-bus.js     | 4 ++--
 config/locales/server.en.yml                                  | 1 +
 config/site_settings.yml                                      | 3 +++
 3 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/app/assets/javascripts/discourse/app/initializers/message-bus.js b/app/assets/javascripts/discourse/app/initializers/message-bus.js
index 9adcabc420a..f5dcf26563e 100644
--- a/app/assets/javascripts/discourse/app/initializers/message-bus.js
+++ b/app/assets/javascripts/discourse/app/initializers/message-bus.js
@@ -64,8 +64,9 @@ export default {
     messageBus.baseUrl =
       siteSettings.long_polling_base_url.replace(/\/$/, "") + "/";
 
+    messageBus.enableChunkedEncoding = siteSettings.enable_chunked_encoding;
+
     if (messageBus.baseUrl !== "/") {
-      // zepto compatible, 1 param only
       messageBus.ajax = function (opts) {
         opts.headers = opts.headers || {};
         opts.headers["X-Shared-Session-Key"] = $(
@@ -90,7 +91,6 @@ export default {
 
     if (user) {
       messageBus.callbackInterval = siteSettings.polling_interval;
-      messageBus.enableLongPolling = true;
     }
   },
 };
diff --git a/config/locales/server.en.yml b/config/locales/server.en.yml
index 47b635c5f21..41b388b2510 100644
--- a/config/locales/server.en.yml
+++ b/config/locales/server.en.yml
@@ -1513,6 +1513,7 @@ en:
     enable_personal_messages: "Allow trust level 1 (configurable via min trust level to send messages) users to create messages and reply to messages. Note that staff can always send messages no matter what."
     enable_system_message_replies: "Allows users to reply to system messages, even if personal messages are disabled"
     enable_long_polling: "Message bus used for notification can use long polling"
+    enable_chunked_encoding: "Enable chunked encoding responses by the server. This feature works on most setups however some proxies may buffer, causing responses to be delayed"
     long_polling_base_url: "Base URL used for long polling (when a CDN is serving dynamic content, be sure to set this to origin pull) eg: http://origin.site.com"
     long_polling_interval: "Amount of time the server should wait before responding to clients when there is no data to send (logged on users only)"
     polling_interval: "When not long polling, how often should logged on clients poll in milliseconds"
diff --git a/config/site_settings.yml b/config/site_settings.yml
index 3882784e157..f4575047061 100644
--- a/config/site_settings.yml
+++ b/config/site_settings.yml
@@ -1724,6 +1724,9 @@ developer:
   enable_long_polling:
     client: true
     default: true
+  enable_chunked_encoding:
+    client: true
+    default: true
   long_polling_interval:
     default: 25000
     max: 25000