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Removing arrow functions from bullet_xhr.jsdfd7708
The Bullet gem is designed to help you increase your application's performance by reducing the number of queries it makes. It will watch your queries while you develop your application and notify you when you should add eager loading (N+1 queries), when you're using eager loading that isn't necessary and when you should use counter cache.
Best practice is to use Bullet in development mode or custom mode (staging, profile, etc.). The last thing you want is your clients getting alerts about how lazy you are.
Bullet gem now supports activerecord >= 4.0 and mongoid >= 4.0.
If you use activerecord 2.x, please use bullet <= 4.5.0
If you use activerecord 3.x, please use bullet < 5.5.0
gem install bullet
or add it into a Gemfile (Bundler):
gem 'bullet', group: 'development'Note: make sure
bullet gem is added after activerecord (rails) and
mongoid.
config/environments/development.rb initializer with the following code:
config.after_initialize do Bullet.enable = true Bullet.sentry = true Bullet.alert = true Bullet.bullet_logger = true Bullet.console = true Bullet.growl = true Bullet.xmpp = { :account => 'bullets_account@jabber.org', :password => 'bullets_password_for_jabber', :receiver => 'your_account@jabber.org', :show_online_status => true } Bullet.rails_logger = true Bullet.honeybadger = true Bullet.bugsnag = true Bullet.airbrake = true Bullet.rollbar = true Bullet.add_footer = true Bullet.skip_html_injection = false Bullet.stacktrace_includes = [ 'your_gem', 'your_middleware' ] Bullet.stacktrace_excludes = [ 'their_gem', 'their_middleware', ['my_file.rb', 'my_method'], ['my_file.rb', 16..20] ] Bullet.slack = { webhook_url: 'http://some.slack.url', channel: '#default', username: 'notifier' } endThe notifier of Bullet is a wrap of uniform_notifier The code above will enable all of the Bullet notification systems: ●
Bullet.enable: enable Bullet gem, otherwise do nothing
●Bullet.alert: pop up a JavaScript alert in the browser
●Bullet.bullet_logger: log to the Bullet log file (Rails.root/log/bullet.log)
●Bullet.console: log warnings to your browser's console.log (Safari/Webkit browsers or Firefox w/Firebug installed)
●Bullet.growl: pop up Growl warnings if your system has Growl installed. Requires a little bit of configuration
●Bullet.xmpp: send XMPP/Jabber notifications to the receiver indicated. Note that the code will currently not handle the adding of contacts, so you will need to make both accounts indicated know each other manually before you will receive any notifications. If you restart the development server frequently, the 'coming online' sound for the Bullet account may start to annoy - in this case set :show_online_status to false; you will still get notifications, but the Bullet account won't announce it's online status anymore.
●Bullet.rails_logger: add warnings directly to the Rails log
●Bullet.honeybadger: add notifications to Honeybadger
●Bullet.bugsnag: add notifications to bugsnag
●Bullet.airbrake: add notifications to airbrake
●Bullet.rollbar: add notifications to rollbar
●Bullet.sentry: add notifications to sentry
●Bullet.add_footer: adds the details in the bottom left corner of the page. Double click the footer or use close button to hide footer.
●Bullet.skip_html_injection: prevents Bullet from injecting XHR into the returned HTML. This must be false for receiving alerts or console logging.
●Bullet.stacktrace_includes: include paths with any of these substrings in the stack trace, even if they are not in your main app
●Bullet.stacktrace_excludes: ignore paths with any of these substrings in the stack trace, even if they are not in your main app.
Each item can be a string (match substring), a regex, or an array where the first item is a path to match, and the second
item is a line number, a Range of line numbers, or a (bare) method name, to exclude only particular lines in a file.
●Bullet.slack: add notifications to slack
●Bullet.raise: raise errors, useful for making your specs fail unless they have optimized queries
Bullet also allows you to disable any of its detectors.
# Each of these settings defaults to true # Detect N+1 queries Bullet.n_plus_one_query_enable = false # Detect eager-loaded associations which are not used Bullet.unused_eager_loading_enable = false # Detect unnecessary COUNT queries which could be avoided # with a counter_cache Bullet.counter_cache_enable = false
Bullet.add_whitelist :type => :n_plus_one_query, :class_name => "Post", :association => :comments Bullet.add_whitelist :type => :unused_eager_loading, :class_name => "Post", :association => :comments Bullet.add_whitelist :type => :counter_cache, :class_name => "Country", :association => :citiesIf you want to skip bullet in some specific controller actions, you can do like
class ApplicationController < ActionController::Base around_action :skip_bullet, if: -> { defined?(Bullet) } def skip_bullet previous_value = Bullet.enable? Bullet.enable = false yield ensure Bullet.enable = previous_value end end
log/bullet.log will look something like this:
●N+1 Query:
2009-08-25 20:40:17[INFO] N+1 Query: PATH_INFO: /posts; model: Post => associations: [comments]·
Add to your finder: :include => [:comments]
2009-08-25 20:40:17[INFO] N+1 Query: method call stack:·
/Users/richard/Downloads/test/app/views/posts/index.html.erb:11:in `_run_erb_app47views47posts47index46html46erb'
/Users/richard/Downloads/test/app/views/posts/index.html.erb:8:in `each'
/Users/richard/Downloads/test/app/views/posts/index.html.erb:8:in `_run_erb_app47views47posts47index46html46erb'
/Users/richard/Downloads/test/app/controllers/posts_controller.rb:7:in `index'
The first two lines are notifications that N+1 queries have been encountered. The remaining lines are stack traces so you can find exactly where the queries were invoked in your code, and fix them.
●Unused eager loading:
2009-08-25 20:53:56[INFO] Unused eager loadings: PATH_INFO: /posts; model: Post => associations: [comments]·
Remove from your finder: :include => [:comments]
These two lines are notifications that unused eager loadings have been encountered.
●Need counter cache:
2009-09-11 09:46:50[INFO] Need Counter Cache
Post => [:comments]
Bullet::ActiveJob in your ApplicationJob.
class ApplicationJob < ActiveJob::Base include Bullet::ActiveJob if Rails.env.development? end
class ApplicationJob < ActiveJob::Base around_perform do |_job, block| Bullet.profile do block.call end end end
Bullet::Rack
configure :development do Bullet.enable = true Bullet.bullet_logger = true use Bullet::Rack end
# config/environments/test.rb config.after_initialize do Bullet.enable = true Bullet.bullet_logger = true Bullet.raise = true # raise an error if n+1 query occurs endThen wrap each test in Bullet api.
# spec/rails_helper.rb if Bullet.enable? config.before(:each) do Bullet.start_request end config.after(:each) do Bullet.perform_out_of_channel_notifications if Bullet.notification? Bullet.end_request end end
BULLET_DEBUG=true env.
$ rails new test_bullet
$ cd test_bullet
$ rails g scaffold post name:string
$ rails g scaffold comment name:string post_id:integer
$ bundle exec rake db:migrate
2. Change app/model/post.rb and app/model/comment.rb
class Post < ActiveRecord::Base has_many :comments end class Comment < ActiveRecord::Base belongs_to :post end3. Go to
rails c and execute
post1 = Post.create(:name => 'first') post2 = Post.create(:name => 'second') post1.comments.create(:name => 'first') post1.comments.create(:name => 'second') post2.comments.create(:name => 'third') post2.comments.create(:name => 'fourth')4. Change the
app/views/posts/index.html.erb to produce a N+1 query
<% @posts.each do |post| %>
<tr>
<td><%= post.name %></td>
<td><%= post.comments.map(&:name) %></td>
<td><%= link_to 'Show', post %></td>
<td><%= link_to 'Edit', edit_post_path(post) %></td>
<td><%= link_to 'Destroy', post, :confirm => 'Are you sure?', :method => :delete %></td>
</tr>
<% end %>
5. Add the bullet gem to the Gemfile
gem "bullet"And run
bundle install
6. enable the Bullet gem with generate command
bundle exec rails g bullet:install
7. Start the server
$ rails s
8. Visit http://localhost:3000/posts in browser, and you will see a popup alert box that says
The request has unused preload associations as follows:
None
The request has N+1 queries as follows:
model: Post => associations: [comment]
which means there is a N+1 query from the Post object to its Comment association.
In the meantime, there's a log appended into log/bullet.log file
2010-03-07 14:12:18[INFO] N+1 Query in /posts
Post => [:comments]
Add to your finder: :include => [:comments]
2010-03-07 14:12:18[INFO] N+1 Query method call stack
/home/flyerhzm/Downloads/test_bullet/app/views/posts/index.html.erb:14:in `_render_template__600522146_80203160_0'
/home/flyerhzm/Downloads/test_bullet/app/views/posts/index.html.erb:11:in `each'
/home/flyerhzm/Downloads/test_bullet/app/views/posts/index.html.erb:11:in `_render_template__600522146_80203160_0'
/home/flyerhzm/Downloads/test_bullet/app/controllers/posts_controller.rb:7:in `index'
The generated SQL is:
Post Load (1.0ms) SELECT * FROM "posts"
Comment Load (0.4ms) SELECT * FROM "comments" WHERE ("comments".post_id = 1)
Comment Load (0.3ms) SELECT * FROM "comments" WHERE ("comments".post_id = 2)
9. To fix the N+1 query, change app/controllers/posts_controller.rb file
def index @posts = Post.includes(:comments) respond_to do |format| format.html # index.html.erb format.xml { render :xml => @posts } end end10. Refresh
http://localhost:3000/posts. Now there's no alert box and nothing new in the log.
The generated SQL is:
Post Load (0.5ms) SELECT * FROM "posts"
Comment Load (0.5ms) SELECT "comments".* FROM "comments" WHERE ("comments".post_id IN (1,2))
N+1 query fixed. Cool!
11. Now simulate unused eager loading. Change
app/controllers/posts_controller.rb and
app/views/posts/index.html.erb
def index @posts = Post.includes(:comments) respond_to do |format| format.html # index.html.erb format.xml { render :xml => @posts } end end
<% @posts.each do |post| %>
<tr>
<td><%= post.name %></td>
<td><%= link_to 'Show', post %></td>
<td><%= link_to 'Edit', edit_post_path(post) %></td>
<td><%= link_to 'Destroy', post, :confirm => 'Are you sure?', :method => :delete %></td>
</tr>
<% end %>
12. Refresh http://localhost:3000/posts, and you will see a popup alert box that says
The request has unused preload associations as follows:
model: Post => associations: [comment]
The request has N+1 queries as follows:
None
Meanwhile, there's a line appended to log/bullet.log
2009-08-25 21:13:22[INFO] Unused preload associations: PATH_INFO: /posts; model: Post => associations: [comments]·
Remove from your finder: :include => [:comments]
13. Simulate counter_cache. Change app/controllers/posts_controller.rb
and app/views/posts/index.html.erb
def index @posts = Post.all respond_to do |format| format.html # index.html.erb format.xml { render :xml => @posts } end end
<% @posts.each do |post| %>
<tr>
<td><%= post.name %></td>
<td><%= post.comments.size %></td>
<td><%= link_to 'Show', post %></td>
<td><%= link_to 'Edit', edit_post_path(post) %></td>
<td><%= link_to 'Destroy', post, :confirm => 'Are you sure?', :method => :delete %></td>
</tr>
<% end %>
14. Refresh http://localhost:3000/posts, then you will see a popup alert box that says
Need counter cache
Post => [:comments]
Meanwhile, there's a line appended to log/bullet.log
2009-09-11 10:07:10[INFO] Need Counter Cache
Post => [:comments]
Copyright (c) 2009 - 2019 Richard Huang (flyerhzm@gmail.com), released under the MIT license