Rails ガイド

 ActiveSupport::Notifications.subscribe "process_action.action_controller" do |event| event.name # => "process_action.action_controller" event.duration # => 10 (in milliseconds) event.allocations # => 1826 event.payload # => {:extra=>information} Rails.logger.info "#{event} Received!" end 

 ActiveSupport::Notifications.subscribe "process_action.action_controller" do |name, started, finished, unique_id, payload| # 自分のコードをここに書く Rails.logger.info "#{name} Received! (started: #{started}, finished: #{finished})" # process_action.action_controller Received! (started: 2019-05-05 13:43:57 -0800, finished: 2019-05-05 13:43:58 -0800) end 

 ActiveSupport::Notifications.monotonic_subscribe "process_action.action_controller" do |name, started, finished, unique_id, payload| # 自分のコードをここに書く duration = finished - started # 1560979.429234 - 1560978.425334 Rails.logger.info "#{name} Received! (duration: #{duration})" # process_action.action_controller Received! (duration: 1.0039) end 

 ActiveSupport::Notifications.subscribe(/action_controller/) do |event| # ActionControllerの全イベントをチェック end 

 { controller: "PostsController", action: "new", params: { "action" => "new", "controller" => "posts" }, headers: #<ActionDispatch::Http::Headers:0x0055a67a519b88>, format: :html, method: "GET", path: "/posts/new" } 

 { controller: "PostsController", action: "index", params: {"action" => "index", "controller" => "posts"}, headers: #<ActionDispatch::Http::Headers:0x0055a67a519b88>, format: :html, method: "GET", path: "/posts", request: #<ActionDispatch::Request:0x00007ff1cb9bd7b8>, response: #<ActionDispatch::Response:0x00007f8521841ec8>, status: 200, view_runtime: 46.848, db_runtime: 0.157 } 

 { status: 302, location: "http://localhost:3000/posts/new", request: <ActionDispatch::Request:0x00007ff1cb9bd7b8> } 

 { filter: ":halting_filter" } 

 { filename: "subscribers.csv", type: "text/csv", disposition: "attachment" } 

 { key: 'posts/1-dashboard-view' } 

 { key: 'posts/1-dashboard-view' } 

 { key: 'posts/1-dashboard-view' } 

 { key: 'posts/1-dashboard-view' } 

 { mailbox: #<RepliesMailbox:0x00007f9f7a8388>, inbound_email: { id: 1, message_id: "0CB459E0-0336-41DA-BC88-E6E28C697DDB@37signals.com", status: "processing" } } 

 { mailer: "Notification", message_id: "4f5b5491f1774_181b23fc3d4434d38138e5@mba.local.mail", subject: "Rails Guides", to: ["users@rails.com", "dhh@rails.com"], from: ["me@rails.com"], date: Sat, 10 Mar 2012 14:18:09 +0100, mail: "...", # （省略） perform_deliveries: true } 

 { mailer: "Notification", action: "welcome_email", args: [] } 

 { identifier: "/Users/adam/projects/notifications/app/views/posts/index.html.erb", layout: "layouts/application", locals: { foo: "bar" } } 

 { identifier: "/Users/adam/projects/notifications/app/views/posts/_form.html.erb", locals: { foo: "bar" } } 

 { identifier: "/Users/adam/projects/notifications/app/views/posts/_post.html.erb", count: 3, cache_hits: 0 } 

 { identifier: "/Users/adam/projects/notifications/app/views/layouts/application.html.erb" } 

 { sql: "SELECT \"posts\".* FROM \"posts\" ", name: "Post Load", binds: [<ActiveModel::Attribute::WithCastValue:0x00007fe19d15dc00>], type_casted_binds: [11], async: false, allow_retry: true, connection: <ActiveRecord::ConnectionAdapters::SQLite3Adapter:0x00007f9f7a838850>, transaction: <ActiveRecord::ConnectionAdapters::RealTransaction:0x0000000121b5d3e0> affected_rows: 0 row_count: 5, statement_name: nil, } 

 { record_count: 1, class_name: "User" } 

 ActiveRecord::Base.transaction do # トランザクションブロック内だが、ここではイベントはまだ何もトリガーされない # 以下の行によってActive Recordがトランザクションを開始する User.count # イベントはここでトリガーされる end 

 ActiveRecord::Base.transaction do |t1| User.count # これはt1のイベントをトリガーする ActiveRecord::Base.transaction do |t2| # 以下の行はt2のイベントを何もトリガーしない # （理由: この例では本物のデータベーストランザクションはt1しかないため） User.first.touch end end 

 ActiveRecord::Base.transaction do |t1| User.count # これはt1のイベントをトリガーする ActiveRecord::Base.transaction(requires_new: true) do |t2| User.first.touch # これはt2のイベントをトリガーする end end 

 { key: "name-of-complicated-computation", store: "ActiveSupport::Cache::MemCacheStore" } 

 { key: "name-of-complicated-computation", store: "ActiveSupport::Cache::MemCacheStore" } 

 { key: "name-of-complicated-computation", store: "ActiveSupport::Cache::MemCacheStore" } 

 { key: "bottles-of-beer", store: "ActiveSupport::Cache::RedisCacheStore", amount: 99 } 

 { key: "bottles-of-beer", store: "ActiveSupport::Cache::RedisCacheStore", amount: 1 } 

 { key: "name-of-complicated-computation", store: "ActiveSupport::Cache::MemCacheStore" } 

 { key: "posts/*", store: "ActiveSupport::Cache::RedisCacheStore" } 

 { store: "ActiveSupport::Cache::MemoryStore", size: 9001 } 

 { store: "ActiveSupport::Cache::MemoryStore", key: 5000, from: 9001 } 

 { key: "name-of-complicated-computation", store: "ActiveSupport::Cache::MemCacheStore" } 

 { serializer: :json_allow_marshal, fallback: :marshal, serialized: "\x04\b{\x06I\"\nHello\x06:\x06ETI\"\nWorld\x06;\x00T", deserialized: { "Hello" => "World" }, } 

 ActiveSupport::Notifications.instrument "my.custom.event", this: :data do # 自分のコードをここに書く end 

 ActiveSupport::Notifications.subscribe "my.custom.event" do |name, started, finished, unique_id, data| puts data.inspect # {:this=>:data} end 

 ActiveSupport::Notifications.instrument "my.custom.event", this: :data ActiveSupport::Notifications.subscribe "my.custom.event" do |name, started, finished, unique_id, data| puts data.inspect # {:this=>:data} end