[Prod] Add instrumentation to login attempts

app/controllers/sessions_controller.rb

@@ -5,15 +5,18 @@ class SessionsController < ApplicationController
 
   def create
     if RateLimiter.check_limit("login:#{request.remote_ip}", 15, 12.hours)
+      DanbooruLogger.add_attributes("user.login" => "rate_limited")
       return redirect_to(new_session_path, :notice => "Username/Password was incorrect")
     end
     session_creator = SessionCreator.new(session, cookies, params[:name], params[:password], request.remote_ip, params[:remember], request.ssl?)
 
     if session_creator.authenticate
       url = params[:url] if params[:url] && params[:url].start_with?("/") && !params[:url].start_with?("//")
+      DanbooruLogger.add_attributes("user.login" => "success")
       redirect_to(url || posts_path, :notice => "You are now logged in")
     else
       RateLimiter.hit("login:#{request.remote_ip}", 6.hours)
+      DanbooruLogger.add_attributes("user.login" => "fail")
       redirect_to(new_session_path, :notice => "Username/Password was incorrect")
     end
   end

app/logical/danbooru_logger.rb

@@ -13,8 +13,12 @@ class DanbooruLogger
   end
 
   def self.initialize(user, remote_ip)
+    add_attributes("user.id" => user.id, "user.name" => user.name, "user.ip" => remote_ip)
+  end
+
+  def self.add_attributes(**)
     return unless defined?(::NewRelic)
 
-    ::NewRelic::Agent.add_custom_attributes({ "user.id" => user.id, "user.name" => user.name, "user.ip" => remote_ip })
+    ::NewRelic::Agent.add_custom_attributes(**)
   end
 end