Plugins can register providers for global settings

app/models/global_setting.rb

@@ -145,14 +145,14 @@ class GlobalSetting
     attr_accessor :provider
   end
 
-
-  if Rails.env == "test"
-    @provider = BlankProvider.new
-  else
-    @provider =
-      FileProvider.from(File.expand_path('../../../config/discourse.conf', __FILE__)) ||
-      EnvProvider.new
+  def self.configure!
+    if Rails.env == "test"
+      @provider = BlankProvider.new
+    else
+      @provider =
+        FileProvider.from(File.expand_path('../../../config/discourse.conf', __FILE__)) ||
+        EnvProvider.new
+    end
   end
 
-  load_defaults
 end

config/application.rb

@@ -6,8 +6,15 @@ require_relative '../lib/discourse_event'
 require_relative '../lib/discourse_plugin'
 require_relative '../lib/discourse_plugin_registry'
 
+require_relative '../lib/plugin_gem'
+
 # Global config
 require_relative '../app/models/global_setting'
+GlobalSetting.configure!
+unless Rails.env.test? && ENV['LOAD_PLUGINS'] != "1"
+  require_relative '../lib/custom_setting_providers'
+end
+GlobalSetting.load_defaults
 
 require 'pry-rails' if Rails.env.development?
 
@@ -15,8 +22,10 @@ if defined?(Bundler)
   Bundler.require(*Rails.groups(assets: %w(development test profile)))
 end
 
+
 module Discourse
   class Application < Rails::Application
+
     def config.database_configuration
       if Rails.env.production?
         GlobalSetting.database_config

lib/custom_setting_providers.rb

@@ -0,0 +1,7 @@
+# Support for plugins to register custom setting providers. They can do this
+# by having a file, `register_provider.rb` in their root that will be run
+# at this point.
+
+Dir.glob(File.join(File.dirname(__FILE__), '../plugins', '*', "register_provider.rb")) do |p|
+  require p
+end

lib/plugin/instance.rb

@@ -363,27 +363,7 @@ JS
   #
   # This is a very rough initial implementation
   def gem(name, version, opts = {})
-    gems_path = File.dirname(path) + "/gems/#{RUBY_VERSION}"
-    spec_path = gems_path + "/specifications"
-    spec_file = spec_path + "/#{name}-#{version}.gemspec"
-    unless File.exists? spec_file
-      command = "gem install #{name} -v #{version} -i #{gems_path} --no-document --ignore-dependencies"
-      if opts[:source]
-        command << " --source #{opts[:source]}"
-      end
-      puts command
-      puts `#{command}`
-    end
-    if File.exists? spec_file
-      spec = Gem::Specification.load spec_file
-      spec.activate
-      unless opts[:require] == false
-        require opts[:require_name] ? opts[:require_name] : name
-      end
-    else
-      puts "You are specifying the gem #{name} in #{path}, however it does not exist!"
-      exit(-1)
-    end
+    PluginGem.load(path, name, version, opts)
   end
 
   def enabled_site_setting(setting=nil)

lib/plugin_gem.rb

@@ -0,0 +1,27 @@
+module PluginGem
+  def self.load(path, name, version, opts=nil)
+    opts ||= {}
+
+    gems_path = File.dirname(path) + "/gems/#{RUBY_VERSION}"
+    spec_path = gems_path + "/specifications"
+    spec_file = spec_path + "/#{name}-#{version}.gemspec"
+    unless File.exists? spec_file
+      command = "gem install #{name} -v #{version} -i #{gems_path} --no-document --ignore-dependencies"
+      if opts[:source]
+        command << " --source #{opts[:source]}"
+      end
+      puts command
+      puts `#{command}`
+    end
+    if File.exists? spec_file
+      spec = Gem::Specification.load spec_file
+      spec.activate
+      unless opts[:require] == false
+        require opts[:require_name] ? opts[:require_name] : name
+      end
+    else
+      puts "You are specifying the gem #{name} in #{path}, however it does not exist!"
+      exit(-1)
+    end
+  end
+end