<%= debug @article %>
<p>
  <b>제목:</b>
  <%= @article.title %>
</p>

--- !ruby/object Article
attributes:
  updated_at: 2008-09-05 22:55:47
  body: Rails 앱을 디버깅하는데 매우 유용한 가이드입니다.
  title: Rails 디버깅 가이드 
  published: t
  id: "1"
  created_at: 2008-09-05 22:55:47
attributes_cache: {}


Title: Rails 디버깅 가이드

<%= simple_format @article.to_yaml %>
<p>
  <b>제목:</b>
  <%= @article.title %>
</p>

--- !ruby/object Article
attributes:
updated_at: 2008-09-05 22:55:47
body: Rails 앱을 디버깅하는데 매우 유용한 가이드입니다.
title: Rails 디버깅 가이드
published: t
id: "1"
created_at: 2008-09-05 22:55:47
attributes_cache: {}

Title: Rails 디버깅 가이드

<%= [1, 2, 3, 4, 5].inspect %>
<p>
  <b>제목:</b>
  <%= @article.title %>
</p>

[1, 2, 3, 4, 5]

제목: Rails 디버깅 가이드

config.logger = Logger.new(STDOUT)
config.logger = Log4r::Logger.new("Application Log")

Rails.logger = Logger.new(STDOUT)
Rails.logger = Log4r::Logger.new("Application Log")

config.log_level = :warn # 환경 initializer에서, 또는
Rails.logger.level = 0 # 언제든지

logger.debug "사람 속성 해시: #{@person.attributes.inspect}"
logger.info "요청을 처리하는 중..."
logger.fatal "복구할 수 없는 오류가 발생하여 애플리케이션을 종료합니다!!!"

class ArticlesController < ApplicationController
  # ...

  def create
    @article = Article.new(article_params)
    logger.debug "새 article: #{@article.attributes.inspect}"
    logger.debug "Article이 유효해야 함: #{@article.valid?}"

    if @article.save
      logger.debug "article이 저장되었고 이제 사용자가 리다이렉트될 것입니다..."
      redirect_to @article, notice: 'Article이 성공적으로 생성되었습니다.'
    else
      render :new, status: :unprocessable_entity
    end
  end

  # ...

  private
    def article_params
      params.expect(article: [:title, :body, :published])
    end
end

Started POST "/articles" for 127.0.0.1 at 2018-10-18 20:09:23 -0400
Processing by ArticlesController#create as HTML
  Parameters: {"utf8"=>"✓", "authenticity_token"=>"XLveDrKzF1SwaiNRPTaMtkrsTzedtebPPkmxEFIU0ordLjICSnXsSNfrdMa4ccyBjuGwnnEiQhEoMN6H1Gtz3A==", "article"=>{"title"=>"Debugging Rails", "body"=>"I'm learning how to print in logs.", "published"=>"0"}, "commit"=>"Create Article"} 
새 article: {"id"=>nil, "title"=>"Debugging Rails", "body"=>"I'm learning how to print in logs.", "published"=>false, "created_at"=>nil, "updated_at"=>nil}
Article이 유효해야 함: true
   (0.0ms)  트랜잭션 시작
  ↳ app/controllers/articles_controller.rb:31
  Article 생성 (0.5ms)  INSERT INTO "articles" ("title", "body", "published", "created_at", "updated_at") VALUES (?, ?, ?, ?, ?)  [["title", "Debugging Rails"], ["body", "I'm learning how to print in logs."], ["published", 0], ["created_at", "2018-10-19 00:09:23.216549"], ["updated_at", "2018-10-19 00:09:23.216549"]]
  ↳ app/controllers/articles_controller.rb:31
   (2.3ms)  트랜잭션 커밋
  ↳ app/controllers/articles_controller.rb:31
article이 저장되었고 이제 사용자가 리다이렉트됩니다...
Redirected to http://localhost:3000/articles/1
Completed 302 Found in 4ms (ActiveRecord: 0.8ms)

irb(main):001:0> Article.pamplemousse
  Article Load (0.4ms)  SELECT "articles".* FROM "articles"
  Comment Load (0.2ms)  SELECT "comments".* FROM "comments" WHERE "comments"."article_id" = ?  [["article_id", 1]]
  Comment Load (0.1ms)  SELECT "comments".* FROM "comments" WHERE "comments"."article_id" = ?  [["article_id", 2]]
  Comment Load (0.1ms)  SELECT "comments".* FROM "comments" WHERE "comments"."article_id" = ?  [["article_id", 3]]
=> #<Comment id: 2, author: "1", body: "그렇게 말하자면...", article_id: 1, created_at: "2018-10-19 00:56:10", updated_at: "2018-10-19 00:56:10">

irb(main):003:0> Article.pamplemousse
  Article Load (0.2ms)  SELECT "articles".* FROM "articles"
  ↳ app/models/article.rb:5
  Comment Load (0.1ms)  SELECT "comments".* FROM "comments" WHERE "comments"."article_id" = ?  [["article_id", 1]]
  ↳ app/models/article.rb:6
  Comment Load (0.1ms)  SELECT "comments".* FROM "comments" WHERE "comments"."article_id" = ?  [["article_id", 2]]
  ↳ app/models/article.rb:6
  Comment Load (0.1ms)  SELECT "comments".* FROM "comments" WHERE "comments"."article_id" = ?  [["article_id", 3]]
  ↳ app/models/article.rb:6
=> #<Comment id: 2, author: "1", body: "음, 사실은...", article_id: 1, created_at: "2018-10-19 00:56:10", updated_at: "2018-10-19 00:56:10">

config.active_job.verbose_enqueue_logs = true

config.active_record.query_log_tags_enabled = true

Article Load (0.2ms)  SELECT "articles".* FROM "articles" /*애플리케이션='Blog',컨트롤러='articles',액션='index'*/

Article Update (0.3ms)  UPDATE "articles" SET "title" = ?, "updated_at" = ? WHERE "posts"."id" = ? /*애플리케이션='Blog',작업='ImproveTitleJob'*/  [["title", "Improved Rails debugging guide"], ["updated_at", "2022-10-16 20:25:40.091371"], ["id", 1]]

logger = ActiveSupport::TaggedLogging.new(Logger.new(STDOUT))
logger.tagged("BCX") { logger.info "Stuff" }                            # "[BCX] Stuff" 로그 출력
logger.tagged("BCX", "Jason") { logger.info "Stuff" }                   # "[BCX] [Jason] Stuff" 로그 출력
logger.tagged("BCX") { logger.tagged("Jason") { logger.info "Stuff" } } # "[BCX] [Jason] Stuff" 로그 출력

logger.debug "Person 속성 해시: #{@person.attributes.inspect}"

logger.debug { "Person 속성 해시: #{@person.attributes.inspect}" }

class PostsController < ApplicationController
  before_action :set_post, only: %i[ show edit update destroy ]

  # GET /posts 또는 /posts.json
  def index
    @posts = Post.all
    debugger
  end
  # ...
end

Processing by PostsController#index as HTML로 처리 중
[2, 11] in ~/projects/rails-guide-example/app/controllers/posts_controller.rb
     2|   before_action :set_post, only: %i[ show edit update destroy ]
     3|
     4|   # GET /posts 또는 /posts.json
     5|   def index
     6|     @posts = Post.all
=>   7|     debugger
     8|   end
     9|
    10|   # GET /posts/1 또는 /posts/1.json
    11|   def show
=>#0    PostsController#index (~projects/rails-guide-example/app/controllers/posts_controller.rb:7)
  #1    ActionController::BasicImplicitRender#send_action(method="index", args=[]) (~/.rbenv/versions/3.0.1/lib/ruby/gems/3.0.0/gems/actionpack-8.1.0.alpha/lib/action_controller/metal/basic_implicit_render.rb:6)
  # 추가 72개의 프레임이 있습니다(모든 프레임을 보려면 `bt` 명령어를 사용하세요)
(rdbg)

(rdbg) @posts    # ruby
[]
(rdbg) self
#<PostsController:0x0000000000aeb0>
(rdbg)

(rdbg) p headers    # 명령어  
=> {"X-Frame-Options"=>"SAMEORIGIN", "X-XSS-Protection"=>"1; mode=block", "X-Content-Type-Options"=>"nosniff", "X-Download-Options"=>"noopen", "X-Permitted-Cross-Domain-Policies"=>"none", "Referrer-Policy"=>"strict-origin-when-cross-origin"}
(rdbg) pp headers    # 명령어
{"X-Frame-Options"=>"SAMEORIGIN",
 "X-XSS-Protection"=>"1; mode=block", 
 "X-Content-Type-Options"=>"nosniff",
 "X-Download-Options"=>"noopen",
 "X-Permitted-Cross-Domain-Policies"=>"none",
 "Referrer-Policy"=>"strict-origin-when-cross-origin"}
(rdbg)

(rdbg) info    # 커맨드  
%self = #<PostsController:0x0000000000af78>
@_action_has_layout = true 
@_action_name = "index"
@_config = {}
@_lookup_context = #<ActionView::LookupContext:0x00007fd91a037e38 @details_key=nil, @digest_cache=...
@_request = #<ActionDispatch::Request GET "http://localhost:3000/posts" for 127.0.0.1>
@_response = #<ActionDispatch::Response:0x00007fd91a03ea08 @mon_data=#<Monitor:0x00007fd91a03e8c8>...
@_response_body = nil
@_routes = nil  
@marked_for_same_origin_verification = true
@posts = []
@rendered_format = nil

ActiveSupport::Configurable#methods: config 
AbstractController::Base#methods:
  action_methods  action_name  action_name=  available_action?  controller_path  inspect
  response_body
ActionController::Metal#methods:
  content_type       content_type=  controller_name  dispatch          headers
  location           location=      media_type       middleware_stack  middleware_stack=
  middleware_stack?  performed?     request          request=          reset_session
  response           response=      response_body=   response_code     session
  set_request!       set_response!  status           status=           to_a
ActionView::ViewPaths#methods:
  _prefixes  any_templates?  append_view_path   details_for_lookup  formats     formats=  locale  
  locale=    lookup_context  prepend_view_path  template_exists?    view_paths
AbstractController::Rendering#methods: view_assigns

# .....

PostsController#methods: create  destroy  edit  index  new  show  update
인스턴스 변수:
  @_action_has_layout  @_action_name    @_config  @_lookup_context                      @_request
  @_response           @_response_body  @_routes  @marked_for_same_origin_verification  @posts
  @rendered_format
클래스 변수: @@raise_on_open_redirects

[20, 29] in ~/projects/rails-guide-example/app/controllers/posts_controller.rb
    20|   end  
    21|  
    22|   # POST /posts 또는 /posts.json
    23|   def create
    24|     @post = Post.new(post_params) 
=>  25|     debugger
    26|
    27|     respond_to do |format|
    28|       if @post.save
    29|         format.html { redirect_to @post, notice: "Post가 성공적으로 생성되었습니다." }
=>#0    PostsController#create at ~/projects/rails-guide-example/app/controllers/posts_controller.rb:25
  #1    ActionController::BasicImplicitRender#send_action(method="create", args=[]) at ~/.rbenv/versions/3.0.1/lib/ruby/gems/3.0.0/gems/actionpack-7.0.0.alpha2/lib/action_controller/metal/basic_implicit_render.rb:6
  # 그리고 72개의 프레임 (모든 프레임을 보려면 `bt` 명령어 사용)
(rdbg) b 28    # break 명령어
#0  BP - Line  /Users/st0012/projects/rails-guide-example/app/controllers/posts_controller.rb:28 (line)

(rdbg) c    # continue 명령어
[23, 32] in ~/projects/rails-guide-example/app/controllers/posts_controller.rb
    23|   def create
    24|     @post = Post.new(post_params)
    25|     debugger
    26|
    27|     respond_to do |format|
=>  28|       if @post.save
    29|         format.html { redirect_to @post, notice: "Post was successfully created." }
    30|         format.json { render :show, status: :created, location: @post }
    31|       else
    32|         format.html { render :new, status: :unprocessable_entity }
=>#0    블록 {|format=#<ActionController::MimeResponds::Collec...|} in create at ~/projects/rails-guide-example/app/controllers/posts_controller.rb:28
  #1    ActionController::MimeResponds#respond_to(mimes=[]) at ~/.rbenv/versions/3.0.1/lib/ruby/gems/3.0.0/gems/actionpack-7.0.0.alpha2/lib/action_controller/metal/mime_responds.rb:205
  # 그리고 74개의 프레임들 (모든 프레임을 보려면 `bt` 명령어 사용)

중단점 #0 BP - 라인 /Users/st0012/projects/rails-guide-example/app/controllers/posts_controller.rb:28 (라인)

[20, 29] in ~/projects/rails-guide-example/app/controllers/posts_controller.rb 
    20|   end
    21|
    22|   # POST /posts 또는 /posts.json 
    23|   def create
    24|     @post = Post.new(post_params)
=>  25|     debugger
    26|
    27|     respond_to do |format|
    28|       if @post.save
    29|         format.html { redirect_to @post, notice: "Post가 성공적으로 생성되었습니다." }
=>#0    PostsController#create at ~/projects/rails-guide-example/app/controllers/posts_controller.rb:25
  #1    ActionController::BasicImplicitRender#send_action(method="create", args=[]) at ~/.rbenv/versions/3.0.1/lib/ruby/gems/3.0.0/gems/actionpack-7.0.0.alpha2/lib/action_controller/metal/basic_implicit_render.rb:6
  # 그리고 72개의 프레임(모든 프레임을 보려면 `bt` 명령어 사용)
(rdbg) b @post.save    # break 명령어
#0  BP - Method  @post.save at /Users/st0012/.rbenv/versions/3.0.1/lib/ruby/gems/3.0.0/gems/activerecord-7.0.0.alpha2/lib/active_record/suppressor.rb:43

(rdbg) c    # continue 명령어 
[39, 48] in ~/.rbenv/versions/3.0.1/lib/ruby/gems/3.0.0/gems/activerecord-7.0.0.alpha2/lib/active_record/suppressor.rb
    39|         SuppressorRegistry.suppressed[name] = previous_state  
    40|       end
    41|     end
    42|  
    43|     def save(**) # :nodoc:
=>  44|       SuppressorRegistry.suppressed[self.class.name] ? true : super
    45|     end
    46|
    47|     def save!(**) # :nodoc:
    48|       SuppressorRegistry.suppressed[self.class.name] ? true : super  
=>#0    ActiveRecord::Suppressor#save(#arg_rest=nil) at ~/.rbenv/versions/3.0.1/lib/ruby/gems/3.0.0/gems/activerecord-7.0.0.alpha2/lib/active_record/suppressor.rb:44
  #1    block {|format=#<ActionController::MimeResponds::Collec...|} in create at ~/projects/rails-guide-example/app/controllers/posts_controller.rb:28
  # 그리고 75개의 프레임 (모든 프레임을 보려면 `bt` 명령어를 사용하세요)

중단점 #0 BP - @post.save 메서드 - /Users/st0012/.rbenv/versions/3.0.1/lib/ruby/gems/3.0.0/gems/activerecord-7.0.0.alpha2/lib/active_record/suppressor.rb:43

[20, 29] in ~/projects/rails-guide-example/app/controllers/posts_controller.rb
    20|   end 
    21|
    22|   # POST /posts or /posts.json 
    23|   def create
    24|     @post = Post.new(post_params)
=>  25|     debugger
    26|
    27|     respond_to do |format|
    28|       if @post.save!
    29|         format.html { redirect_to @post, notice: "Post가 성공적으로 생성되었습니다." }
=>#0    PostsController#create at ~/projects/rails-guide-example/app/controllers/posts_controller.rb:25
  #1    ActionController::BasicImplicitRender#send_action(method="create", args=[]) at ~/.rbenv/versions/3.0.1/lib/ruby/gems/3.0.0/gems/actionpack-7.0.0.alpha2/lib/action_controller/metal/basic_implicit_render.rb:6
  # 그리고 72개의 프레임 (모든 프레임을 보려면 `bt` 명령어 사용)
(rdbg) catch ActiveRecord::RecordInvalid    # 명령어  
#1  BP - Catch  "ActiveRecord::RecordInvalid"

(rdbg) c    # continue 명령어
[75, 84] in ~/.rbenv/versions/3.0.1/lib/ruby/gems/3.0.0/gems/activerecord-7.0.0.alpha2/lib/active_record/validations.rb
    75|     def default_validation_context
    76|       new_record? ? :create : :update
    77|     end
    78|
    79|     def raise_validation_error 
=>  80|       raise(RecordInvalid.new(self))
    81|     end
    82|
    83|     def perform_validations(options = {})
    84|       options[:validate] == false || valid?(options[:context])
=>#0    ActiveRecord::Validations#raise_validation_error at ~/.rbenv/versions/3.0.1/lib/ruby/gems/3.0.0/gems/activerecord-7.0.0.alpha2/lib/active_record/validations.rb:80
  #1    ActiveRecord::Validations#save!(options={}) at ~/.rbenv/versions/3.0.1/lib/ruby/gems/3.0.0/gems/activerecord-7.0.0.alpha2/lib/active_record/validations.rb:53
  # and 88 frames (`bt` 명령어로 모든 프레임을 볼 수 있음)

중단점 #1에 의해 정지됨 BP - Catch "ActiveRecord::RecordInvalid"

(rdbg) c    # continue 명령어 
[173, 182] in ~/.rbenv/versions/3.0.1/lib/ruby/gems/3.0.0/gems/actionpack-7.0.0.alpha2/lib/action_controller/metal.rb
   173|       body = [body] unless body.nil? || body.respond_to?(:each)  
   174|       response.reset_body!
   175|       return unless body
   176|       response.body = body
   177|       super
=> 178|     end
   179|
   180|     # render나 redirect가 이미 발생했는지 테스트합니다.
   181|     def performed?
   182|       response_body || response.committed?
=>#0    ActionController::Metal#response_body=(body=["<html><body>You are being <a href=\"ht...) at ~/.rbenv/versions/3.0.1/lib/ruby/gems/3.0.0/gems/actionpack-7.0.0.alpha2/lib/action_controller/metal.rb:178 #=> ["<html><body>You are being <a href=\"ht...
  #1    ActionController::Redirecting#redirect_to(options=#<Post id: 13, title: "qweqwe", content:..., response_options={:allow_other_host=>false}) at ~/.rbenv/versions/3.0.1/lib/ruby/gems/3.0.0/gems/actionpack-7.0.0.alpha2/lib/action_controller/metal/redirecting.rb:74
  # 그리고 82개의 프레임(모든 프레임을 보려면 `bt` 명령어 사용)

중단점 #0  BP - Watch  #<PostsController:0x00007fce69ca5320> @_response_body =  -> ["<html><body>You are being <a href=\"http://localhost:3000/posts/13\">redirected</a>.</body></html>"]
(rdbg)

[2, 11] in ~/projects/rails-guide-example/app/controllers/posts_controller.rb
     2|   before_action :set_post, only: %i[ show edit update destroy ]
     3|
     4|   # GET /posts 또는 /posts.json
     5|   def index
     6|     @posts = Post.all
=>   7|     debugger(do: "info") 
     8|   end
     9|
    10|   # GET /posts/1 또는 /posts/1.json 
    11|   def show
=>#0    PostsController#index at ~/projects/rails-guide-example/app/controllers/posts_controller.rb:7
  #1    ActionController::BasicImplicitRender#send_action(method="index", args=[]) at ~/.rbenv/versions/3.0.1/lib/ruby/gems/3.0.0/gems/actionpack-7.0.0.alpha2/lib/action_controller/metal/basic_implicit_render.rb:6
  # 그리고 72개의 프레임 (모든 프레임을 보려면 'bt' 명령어 사용)
(rdbg:binding.break) info
%self = #<PostsController:0x00000000017480>
@_action_has_layout = true
@_action_name = "index"
@_config = {}
@_lookup_context = #<ActionView::LookupContext:0x00007fce3ad336b8 @details_key=nil, @digest_cache=...
@_request = #<ActionDispatch::Request GET "http://localhost:3000/posts" for 127.0.0.1>
@_response = #<ActionDispatch::Response:0x00007fce3ad397e8 @mon_data=#<Monitor:0x00007fce3ad396a8>...
@_response_body = nil
@_routes = nil
@marked_for_same_origin_verification = true
@posts = #<ActiveRecord::Relation [#<Post id: 2, title: "qweqwe", content: "qweqwe", created_at: "...
@rendered_format = nil

def create
  debugger(do: "catch ActiveRecord::RecordInvalid do: bt 10")
  # ...
end

(rdbg:binding.break) ActiveRecord::RecordInvalid를 catch하려면: bt 10
#0  BP - Catch  "ActiveRecord::RecordInvalid" 
[75, 84] in ~/.rbenv/versions/3.0.1/lib/ruby/gems/3.0.0/gems/activerecord-7.0.0.alpha2/lib/active_record/validations.rb
    75|     def default_validation_context
    76|       new_record? ? :create : :update
    77|     end
    78|
    79|     def raise_validation_error
=>  80|       raise(RecordInvalid.new(self))  
    81|     end
    82|
    83|     def perform_validations(options = {})
    84|       options[:validate] == false || valid?(options[:context])
=>#0    ActiveRecord::Validations#raise_validation_error in ~/.rbenv/versions/3.0.1/lib/ruby/gems/3.0.0/gems/activerecord-7.0.0.alpha2/lib/active_record/validations.rb:80
  #1    ActiveRecord::Validations#save!(options={}) in ~/.rbenv/versions/3.0.1/lib/ruby/gems/3.0.0/gems/activerecord-7.0.0.alpha2/lib/active_record/validations.rb:53
  # 그리고 88개의 프레임 (모든 프레임을 보려면 'bt' 명령어를 사용하세요)

Stop by #0  BP - "ActiveRecord::RecordInvalid" 예외 캐치

(rdbg:catch) bt 10
=>#0    ~/.rbenv/versions/3.0.1/lib/ruby/gems/3.0.0/gems/activerecord-7.0.0.alpha2/lib/active_record/validations.rb:80의 ActiveRecord::Validations#raise_validation_error 
  #1    ~/.rbenv/versions/3.0.1/lib/ruby/gems/3.0.0/gems/activerecord-7.0.0.alpha2/lib/active_record/validations.rb:53의 ActiveRecord::Validations#save!(options={})
  #2    ~/.rbenv/versions/3.0.1/lib/ruby/gems/3.0.0/gems/activerecord-7.0.0.alpha2/lib/active_record/transactions.rb:302의 save! 블록 내부

class PostsController < ApplicationController
  def new
    console
    @post = Post.new
  end
end

<% console %>

<h2>새 게시물</h2>