From a91843f0dc7b97e700dc85505404eafd62b7f8c5 Mon Sep 17 00:00:00 2001
From: Daniel Waterworth <me@danielwaterworth.com>
Date: Mon, 30 Mar 2020 12:01:06 +0100
Subject: [PATCH] REFACTOR: Move the multisite middleware to the front

Both request tracking and message bus rely on multisite before the
middleware has run which is not ideal.
---
 ...st_tracker.rb => 200-first_middlewares.rb} | 17 ++++++++++++++--
 .../freedom_patches/rails_multisite.rb        |  8 --------
 lib/middleware/request_tracker.rb             | 20 ++++++-------------
 3 files changed, 21 insertions(+), 24 deletions(-)
 rename config/initializers/{200-message_bus_request_tracker.rb => 200-first_middlewares.rb} (58%)
 rename config/initializers/004-rails_multisite.rb => lib/freedom_patches/rails_multisite.rb (77%)

diff --git a/config/initializers/200-message_bus_request_tracker.rb b/config/initializers/200-first_middlewares.rb
similarity index 58%
rename from config/initializers/200-message_bus_request_tracker.rb
rename to config/initializers/200-first_middlewares.rb
index c0ebcfcb1b6..6ae5816fbaf 100644
--- a/config/initializers/200-message_bus_request_tracker.rb
+++ b/config/initializers/200-first_middlewares.rb
@@ -1,9 +1,11 @@
 # frozen_string_literal: true
 
-# we want MesageBus in the absolute front
+# we want MesageBus to be close to the front
 # this is important cause the vast majority of web requests go to it
 # this allows us to avoid full middleware crawls each time
-# Pending https://github.com/rails/rails/pull/27936
+#
+# We aren't manipulating the middleware stack directly because of
+# https://github.com/rails/rails/pull/27936
 session_operations = Rails::Configuration::MiddlewareStackProxy.new([
    [:delete, MessageBus::Rack::Middleware],
    [:unshift, MessageBus::Rack::Middleware],
@@ -21,3 +23,14 @@ if Rails.env != 'development' || ENV['TRACK_REQUESTS']
     MethodProfiler.ensure_discourse_instrumentation!
   end
 end
+
+if Rails.configuration.multisite
+  # Multisite needs to be first, because the request tracker and message bus
+  # rely on it
+  session_operations = Rails::Configuration::MiddlewareStackProxy.new([
+     [:delete, RailsMultisite::Middleware],
+     [:unshift, RailsMultisite::Middleware, RailsMultisite::DiscoursePatches.config],
+  ])
+
+  Rails.configuration.middleware = Rails.configuration.middleware + session_operations
+end
diff --git a/config/initializers/004-rails_multisite.rb b/lib/freedom_patches/rails_multisite.rb
similarity index 77%
rename from config/initializers/004-rails_multisite.rb
rename to lib/freedom_patches/rails_multisite.rb
index 21543492ea8..c4627daa2a7 100644
--- a/config/initializers/004-rails_multisite.rb
+++ b/lib/freedom_patches/rails_multisite.rb
@@ -26,11 +26,3 @@ module RailsMultisite
     end
   end
 end
-
-if Rails.configuration.multisite
-  Rails.configuration.middleware.swap(
-    RailsMultisite::Middleware,
-    RailsMultisite::Middleware,
-    RailsMultisite::DiscoursePatches.config
-  )
-end
diff --git a/lib/middleware/request_tracker.rb b/lib/middleware/request_tracker.rb
index 41ad8a60b41..4fbe3d1b2a3 100644
--- a/lib/middleware/request_tracker.rb
+++ b/lib/middleware/request_tracker.rb
@@ -51,14 +51,6 @@ class Middleware::RequestTracker
     @app = app
   end
 
-  def self.log_request_on_site(data, host)
-    RailsMultisite::ConnectionManagement.with_hostname(host) do
-      unless Discourse.pg_readonly_mode?
-        log_request(data)
-      end
-    end
-  end
-
   def self.log_request(data)
     status = data[:status]
     track_view = data[:track_view]
@@ -135,7 +127,6 @@ class Middleware::RequestTracker
 
     # we got to skip this on error ... its just logging
     data = self.class.get_data(env, result, info) rescue nil
-    host = RailsMultisite::ConnectionManagement.host(env)
 
     if data
       if result && (headers = result[1])
@@ -146,7 +137,7 @@ class Middleware::RequestTracker
         @@detailed_request_loggers.each { |logger| logger.call(env, data) }
       end
 
-      log_later(data, host)
+      log_later(data)
     end
 
   end
@@ -296,10 +287,11 @@ class Middleware::RequestTracker
     end
   end
 
-  def log_later(data, host)
-    Scheduler::Defer.later("Track view", _db = nil) do
-      self.class.log_request_on_site(data, host)
+  def log_later(data)
+    Scheduler::Defer.later("Track view") do
+      unless Discourse.pg_readonly_mode?
+        self.class.log_request(data)
+      end
     end
   end
-
 end