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@chancancode
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Ƅ
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http://rails-weekly.goodbits.io
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gem install canada
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>> require 'canada'
=> true
>> [].empty_eh?
=> true
>> [1,2,3].empty_eh?
=> false
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October 2015
@ vancouver ruby
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Software Writer
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I have a very particular set of skills,
skills I have acquired over a very long
career. Skills that make me a nightmare
for bugs like you. I will look for you, I will
find you, and I will fix you.
What I Think I Do
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What I Actually Do
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What My Clients Think I Do
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Rails
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Magic
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Black Magic
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Rails has no magic folks,
it has
sane defaults and conventions,
take a "magical" feeling as "I need
to grok the docs on this"
Xavier Noria
@fxn
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@fxn it feels like magic because
even before you grok it, it still
works.
The cost of learning is not
piled on up front.
Sebastian Delmont
@sd
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Black Magic
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Black Box
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Pry Open
The Black Box
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NoMethodError
NameError
TypeError
WrongEncodingError
ArgumentError
Circular dependency detected while autoloading consta
veRecord::StatementInvalid
Redis::CannotConn
RangeError
ActiveRecord::Subclas
JSON::ParserError
Dalli::RingErro
SystemStackEr
ActiveJob::DeserializationErro
RuntimeError
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Take a deep breath.
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1. You wrote some code
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1. You wrote some code
2. You ran the code
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1. You wrote some code
2. You ran the code
3. You expected something to happen
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1. You wrote some code
2. You ran the code
3. You expected something to happen
4. That didn’t happen
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1. You wrote the code
2. You ran the code
3. You expected something to happen
4. That didn’t happen
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1. You wrote the code
2. You have access to the code
3. You expected something to happen
4. That didn’t happen
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1. You wrote the code
2. You have access to the code
3. You know what went wrong
4. That didn’t happen
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1. You wrote the code
2. You have access to the code
3. You know what went wrong
4. Your bug is not going anywhere
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Documentation
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http://api.rubyonrails.org/
Latest Stable Release
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http://api.rubyonrails.org/
Latest Stable Release
http://api.rubyonrails.org/v4.1.10/
Arbitrary Version
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http://api.rubyonrails.org/
Latest Stable Release
http://api.rubyonrails.org/v4.1.10/
Arbitrary Version
http://edgeapi.rubyonrails.org/
Edge Rails
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http://guides.rubyonrails.org/
Latest Stable Release
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http://guides.rubyonrails.org/
Latest Stable Release
http://guides.rubyonrails.org/v4.1.10/
Arbitrary Version
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http://guides.rubyonrails.org/
Latest Stable Release
http://guides.rubyonrails.org/v4.1.10/
Arbitrary Version
http://edgeguides.rubyonrails.org/
Edge Rails
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Updating Rails
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Rails 4.2.1
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Rails 4.2.1
Major Version
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Rails 4.2.1
“Minor” Version
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Rails 4.2.1
Patch Version
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Rails 4.2.1
Release Series
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gem “rails”, github: “rails/rails”, branch: “4-2-stable”
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Stack Trace
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ActiveRecord::SubclassNotFound (The single-table inheritance...):
app/models/user.rb:3:in `ensure_permission'
app/models/post.rb:5:in `ensure_author'
app/controllers/posts_controller.rb:30:in `block in create'
app/controllers/posts_controller.rb:29:in `create'
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app/models/user.rb:3:in `ensure_permission'
app/models/post.rb:5:in `ensure_author'
app/controllers/posts_controller.rb:30:in `block in create'
app/controllers/posts_controller.rb:29:in `create'
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PostsController (block in #create)
Post#ensure_author
User#ensure_permission
PostsController#create
app/models/user.rb:3:in `ensure_permission'
app/models/post.rb:5:in `ensure_author'
app/controllers/posts_controller.rb:30:in `block in create'
app/controllers/posts_controller.rb:29:in `create'
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PostsController (block in #create)
Post#ensure_author
User#ensure_permission
PostsController#create
class PostsController < ...
def create
@post = Post.new(post_params)
respond_to do |format|
if @post.save
...
end
end
end
end
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PostsController (block in #create)
Post#ensure_author
User#ensure_permission
PostsController#create
class PostsController < ...
def create
@post = Post.new(post_params)
respond_to do |format|
if @post.save
...
end
end
end
end
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PostsController (block in #create)
Post#ensure_author
User#ensure_permission
PostsController#create
class Post < ActiveRecord::Base
belongs_to :author, class_name: "User"
before_save :ensure_author
def ensure_author
author.ensure_permission(:authorship)
end
end
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PostsController (block in #create)
Post#ensure_author
User#ensure_permission
PostsController#create
class User < ActiveRecord::Base
has_many :permissions
has_many :posts
def ensure_permission(role)
permissions.find_by_type!(role)
end
end
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PostsController (block in #create)
Post#ensure_author
User#ensure_permission
PostsController#create
ActiveRecord::SubclassNotFound (The single-table inheritance...):
app/models/user.rb:3:in `ensure_permission'
app/models/post.rb:5:in `ensure_author'
app/controllers/posts_controller.rb:30:in `block in create'
app/controllers/posts_controller.rb:29:in `create'
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app/models/user.rb:3:in `ensure_permission'
app/models/post.rb:5:in `ensure_author'
? ? ? ? ? ? ? ? ? ?
app/controllers/posts_controller.rb:30:in `block in create'
app/controllers/posts_controller.rb:29:in `create'
? ? ? ? ? ? ? ? ? ?
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Backtrace Cleaner
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# Be sure to restart your server when you modify this file.
# You can add backtrace silencers for libraries that you're
# using but don't wish to see in your backtraces.
#
# Rails.backtrace_cleaner.add_silencer do |line|
# line =~ /my_noisy_library/
# end
# You can also remove all the silencers if you're trying to
# debug a problem that might stem from framework code.
#
# Rails.backtrace_cleaner.remove_silencers!
config/initializers/backtrace_silencers.rb
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# Be sure to restart your server when you modify this file.
# You can add backtrace silencers for libraries that you're
# using but don't wish to see in your backtraces.
#
# Rails.backtrace_cleaner.add_silencer do |line|
# line =~ /my_noisy_library/
# end
# You can also remove all the silencers if you're trying to
# debug a problem that might stem from framework code.
Rails.backtrace_cleaner.remove_silencers!
config/initializers/backtrace_silencers.rb
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ActiveRecord::SubclassNotFound (The single-table inheritance...):
/rails/activerecord/lib/active_record/inheritance.rb:176:in `rescue in find_sti_class'
/rails/activerecord/lib/active_record/inheritance.rb:170:in `find_sti_class'
/rails/activerecord/lib/active_record/inheritance.rb:159:in `discriminate_class_for_record'
/rails/activerecord/lib/active_record/persistence.rb:67:in `instantiate'
/rails/activerecord/lib/active_record/querying.rb:50:in `block (2 levels) in find_by_sql'
/rails/activerecord/lib/active_record/result.rb:51:in `block in each'
/rails/activerecord/lib/active_record/result.rb:51:in `each'
/rails/activerecord/lib/active_record/result.rb:51:in `each'
/rails/activerecord/lib/active_record/querying.rb:50:in `map'
/rails/activerecord/lib/active_record/querying.rb:50:in `block in find_by_sql'
/rails/activesupport/lib/active_support/notifications/instrumenter.rb:20:in `instrument'
/rails/activerecord/lib/active_record/querying.rb:49:in `find_by_sql'
/rails/activerecord/lib/active_record/statement_cache.rb:107:in `execute'
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ActiveRecord::SubclassNotFound (The single-table inheritance...):
/rails/activerecord/lib/active_record/inheritance.rb:176:in `rescue in find_sti_class'
/rails/activerecord/lib/active_record/inheritance.rb:170:in `find_sti_class'
/rails/activerecord/lib/active_record/inheritance.rb:159:in `discriminate_class_for_record'
/rails/activerecord/lib/active_record/persistence.rb:67:in `instantiate'
/rails/activerecord/lib/active_record/querying.rb:50:in `block (2 levels) in find_by_sql'
/rails/activerecord/lib/active_record/result.rb:51:in `block in each'
/rails/activerecord/lib/active_record/result.rb:51:in `each'
/rails/activerecord/lib/active_record/result.rb:51:in `each'
/rails/activerecord/lib/active_record/querying.rb:50:in `map'
/rails/activerecord/lib/active_record/querying.rb:50:in `block in find_by_sql'
/rails/activesupport/lib/active_support/notifications/instrumenter.rb:20:in `instrument'
/rails/activerecord/lib/active_record/querying.rb:49:in `find_by_sql'
/rails/activerecord/lib/active_record/statement_cache.rb:107:in `execute'
/rails/activerecord/lib/active_record/core.rb:192:in `find_by'
/rails/activerecord/lib/active_record/dynamic_matchers.rb:65:in `find_by_type_and_user_id'
/rails/activerecord/lib/active_record/dynamic_matchers.rb:19:in `method_missing'
app/models/user.rb:3:in `ensure_permission'
app/models/post.rb:5:in `ensure_author'
/rails/activesupport/lib/active_support/callbacks.rb:428:in `block in make_lambda'
/rails/activesupport/lib/active_support/callbacks.rb:164:in `call'
/rails/activesupport/lib/active_support/callbacks.rb:164:in `block (2 levels) in halting'
/rails/activesupport/lib/active_support/callbacks.rb:599:in `call'
/rails/activesupport/lib/active_support/callbacks.rb:599:in `block (2 levels) in default_terminator'
/rails/activesupport/lib/active_support/callbacks.rb:598:in `catch'
/rails/activesupport/lib/active_support/callbacks.rb:598:in `block in default_terminator'
/rails/activesupport/lib/active_support/callbacks.rb:165:in `call'
/rails/activesupport/lib/active_support/callbacks.rb:165:in `block in halting'
/rails/activesupport/lib/active_support/callbacks.rb:500:in `call'
/rails/activesupport/lib/active_support/callbacks.rb:500:in `block in call'
/rails/activesupport/lib/active_support/callbacks.rb:500:in `each'
/rails/activesupport/lib/active_support/callbacks.rb:500:in `call'
/rails/activesupport/lib/active_support/callbacks.rb:90:in `run_callbacks'
/rails/activerecord/lib/active_record/callbacks.rb:301:in `create_or_update'
/rails/activerecord/lib/active_record/persistence.rb:151:in `save!'
/rails/activerecord/lib/active_record/validations.rb:43:in `save!'
/rails/activerecord/lib/active_record/attribute_methods/dirty.rb:29:in `save!'
/rails/activerecord/lib/active_record/transactions.rb:303:in `block in save!'
/rails/activerecord/lib/active_record/transactions.rb:374:in `block in with_transaction_returning_status'
/rails/activerecord/lib/active_record/connection_adapters/abstract/database_statements.rb:211:in `block in transaction'
/rails/activerecord/lib/active_record/connection_adapters/abstract/transaction.rb:183:in `within_new_transaction'
/rails/activerecord/lib/active_record/connection_adapters/abstract/database_statements.rb:211:in `transaction'
/rails/activerecord/lib/active_record/transactions.rb:210:in `transaction'
/rails/activerecord/lib/active_record/transactions.rb:371:in `with_transaction_returning_status'
/rails/activerecord/lib/active_record/transactions.rb:303:in `save!'
/rails/activerecord/lib/active_record/suppressor.rb:42:in `save!'
app/controllers/posts_controller.rb:30:in `block in create'
/rails/actionpack/lib/action_controller/metal/mime_responds.rb:190:in `respond_to'
app/controllers/posts_controller.rb:29:in `create'
/rails/actionpack/lib/action_controller/metal/implicit_render.rb:4:in `send_action'
/rails/actionpack/lib/abstract_controller/base.rb:189:in `process_action'
/rails/actionpack/lib/action_controller/metal/rendering.rb:21:in `process_action'
/rails/actionpack/lib/abstract_controller/callbacks.rb:20:in `block in process_action'
/rails/activesupport/lib/active_support/callbacks.rb:117:in `call'
/rails/activesupport/lib/active_support/callbacks.rb:117:in `call'
/rails/activesupport/lib/active_support/callbacks.rb:558:in `block (2 levels) in compile'
/rails/activesupport/lib/active_support/callbacks.rb:501:in `call'
/rails/activesupport/lib/active_support/callbacks.rb:501:in `call'
/rails/activesupport/lib/active_support/callbacks.rb:90:in `run_callbacks'
/rails/actionpack/lib/abstract_controller/callbacks.rb:19:in `process_action'
/rails/actionpack/lib/action_controller/metal/rescue.rb:29:in `process_action'
/rails/actionpack/lib/action_controller/metal/instrumentation.rb:32:in `block in process_action'
/rails/activesupport/lib/active_support/notifications.rb:164:in `block in instrument'
/rails/activesupport/lib/active_support/notifications/instrumenter.rb:20:in `instrument'
/rails/activesupport/lib/active_support/notifications.rb:164:in `instrument'
/rails/actionpack/lib/action_controller/metal/instrumentation.rb:30:in `process_action'
/rails/actionpack/lib/action_controller/metal/params_wrapper.rb:249:in `process_action'
/rails/activerecord/lib/active_record/railties/controller_runtime.rb:18:in `process_action'
/rails/actionpack/lib/abstract_controller/base.rb:128:in `process'
/rails/actionview/lib/action_view/rendering.rb:30:in `process'
/rails/actionpack/lib/action_controller/metal.rb:194:in `dispatch'
/rails/actionpack/lib/action_controller/metal.rb:241:in `block in action'
/rails/actionpack/lib/action_dispatch/routing/route_set.rb:73:in `call'
/rails/actionpack/lib/action_dispatch/routing/route_set.rb:73:in `dispatch'
/rails/actionpack/lib/action_dispatch/routing/route_set.rb:42:in `serve'
/rails/actionpack/lib/action_dispatch/journey/router.rb:43:in `block in serve'
/rails/actionpack/lib/action_dispatch/journey/router.rb:30:in `each'
/rails/actionpack/lib/action_dispatch/journey/router.rb:30:in `serve'
/rails/actionpack/lib/action_dispatch/routing/route_set.rb:769:in `call'
rack (1.6.0) lib/rack/etag.rb:24:in `call'
rack (1.6.0) lib/rack/conditionalget.rb:38:in `call'
rack (1.6.0) lib/rack/head.rb:13:in `call'
/rails/actionpack/lib/action_dispatch/middleware/params_parser.rb:27:in `call'
/rails/actionpack/lib/action_dispatch/middleware/flash.rb:266:in `call'
rack (1.6.0) lib/rack/session/abstract/id.rb:225:in `context'
rack (1.6.0) lib/rack/session/abstract/id.rb:220:in `call'
/rails/actionpack/lib/action_dispatch/middleware/cookies.rb:560:in `call'
/rails/activerecord/lib/active_record/query_cache.rb:36:in `call'
/rails/activerecord/lib/active_record/connection_adapters/abstract/connection_pool.rb:642:in `call'
/rails/activerecord/lib/active_record/migration.rb:378:in `call'
/rails/actionpack/lib/action_dispatch/middleware/callbacks.rb:29:in `block in call'
/rails/activesupport/lib/active_support/callbacks.rb:86:in `run_callbacks'
/rails/actionpack/lib/action_dispatch/middleware/callbacks.rb:27:in `call'
/rails/actionpack/lib/action_dispatch/middleware/reloader.rb:73:in `call'
/rails/actionpack/lib/action_dispatch/middleware/remote_ip.rb:78:in `call'
/rails/actionpack/lib/action_dispatch/middleware/debug_exceptions.rb:47:in `call'
/Users/godfrey/.rvm/gems/ruby-2.2.2/bundler/gems/web-console-f5255e303d66/lib/web_console/middleware.rb:37:in `call'
/rails/actionpack/lib/action_dispatch/middleware/show_exceptions.rb:30:in `call'
/rails/railties/lib/rails/rack/logger.rb:38:in `call_app'
/rails/railties/lib/rails/rack/logger.rb:20:in `block in call'
/rails/activesupport/lib/active_support/tagged_logging.rb:70:in `block in tagged'
/rails/activesupport/lib/active_support/tagged_logging.rb:26:in `tagged'
/rails/activesupport/lib/active_support/tagged_logging.rb:70:in `tagged'
/rails/railties/lib/rails/rack/logger.rb:20:in `call'
/rails/actionpack/lib/action_dispatch/middleware/request_id.rb:25:in `call'
rack (1.6.0) lib/rack/methodoverride.rb:22:in `call'
rack (1.6.0) lib/rack/runtime.rb:18:in `call'
/rails/activesupport/lib/active_support/cache/strategy/local_cache_middleware.rb:28:in `call'
rack (1.6.0) lib/rack/lock.rb:17:in `call'
/rails/actionpack/lib/action_dispatch/middleware/static.rb:115:in `call'
rack (1.6.0) lib/rack/sendfile.rb:113:in `call'
/rails/railties/lib/rails/engine.rb:518:in `call'
/rails/railties/lib/rails/application.rb:165:in `call'
rack (1.6.0) lib/rack/lock.rb:17:in `call'
rack (1.6.0) lib/rack/content_length.rb:15:in `call'
rack (1.6.0) lib/rack/handler/webrick.rb:89:in `service'
/Users/godfrey/.rvm/rubies/ruby-2.2.2/lib/ruby/2.2.0/webrick/httpserver.rb:138:in `service'
/Users/godfrey/.rvm/rubies/ruby-2.2.2/lib/ruby/2.2.0/webrick/httpserver.rb:94:in `run'
/Users/godfrey/.rvm/rubies/ruby-2.2.2/lib/ruby/2.2.0/webrick/server.rb:294:in `block in start_thread'
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ActiveRecord::SubclassNotFound (The single-table inheritance...):
/rails/activerecord/lib/active_record/inheritance.rb:176:in `rescue in find_sti_class'
/rails/activerecord/lib/active_record/inheritance.rb:170:in `find_sti_class'
/rails/activerecord/lib/active_record/inheritance.rb:159:in `discriminate_class_for_record'
/rails/activerecord/lib/active_record/persistence.rb:67:in `instantiate'
/rails/activerecord/lib/active_record/querying.rb:50:in `block (2 levels) in find_by_sql'
/rails/activerecord/lib/active_record/result.rb:51:in `block in each'
/rails/activerecord/lib/active_record/result.rb:51:in `each'
/rails/activerecord/lib/active_record/result.rb:51:in `each'
/rails/activerecord/lib/active_record/querying.rb:50:in `map'
/rails/activerecord/lib/active_record/querying.rb:50:in `block in find_by_sql'
/rails/activesupport/lib/active_support/notifications/instrumenter.rb:20:in `instrument'
/rails/activerecord/lib/active_record/querying.rb:49:in `find_by_sql'
/rails/activerecord/lib/active_record/statement_cache.rb:107:in `execute'
/rails/activerecord/lib/active_record/core.rb:192:in `find_by'
/rails/activerecord/lib/active_record/dynamic_matchers.rb:65:in `find_by_type_and_user_id'
/rails/activerecord/lib/active_record/dynamic_matchers.rb:19:in `method_missing'
app/models/user.rb:3:in `ensure_permission'
app/models/post.rb:5:in `ensure_author'
/rails/activesupport/lib/active_support/callbacks.rb:428:in `block in make_lambda'
/rails/activesupport/lib/active_support/callbacks.rb:164:in `call'
/rails/activesupport/lib/active_support/callbacks.rb:164:in `block (2 levels) in halting'
/rails/activesupport/lib/active_support/callbacks.rb:599:in `call'
/rails/activesupport/lib/active_support/callbacks.rb:599:in `block (2 levels) in default_terminator'
/rails/activesupport/lib/active_support/callbacks.rb:598:in `catch'
/rails/activesupport/lib/active_support/callbacks.rb:598:in `block in default_terminator'
/rails/activesupport/lib/active_support/callbacks.rb:165:in `call'
/rails/activesupport/lib/active_support/callbacks.rb:165:in `block in halting'
/rails/activesupport/lib/active_support/callbacks.rb:500:in `call'
/rails/activesupport/lib/active_support/callbacks.rb:500:in `block in call'
/rails/activesupport/lib/active_support/callbacks.rb:500:in `each'
/rails/activesupport/lib/active_support/callbacks.rb:500:in `call'
/rails/activesupport/lib/active_support/callbacks.rb:90:in `run_callbacks'
/rails/activerecord/lib/active_record/callbacks.rb:301:in `create_or_update'
/rails/activerecord/lib/active_record/persistence.rb:151:in `save!'
/rails/activerecord/lib/active_record/validations.rb:43:in `save!'
/rails/activerecord/lib/active_record/attribute_methods/dirty.rb:29:in `save!'
/rails/activerecord/lib/active_record/transactions.rb:303:in `block in save!'
/rails/activerecord/lib/active_record/transactions.rb:374:in `block in with_transaction_returning_status'
/rails/activerecord/lib/active_record/connection_adapters/abstract/database_statements.rb:211:in `block in transaction'
/rails/activerecord/lib/active_record/connection_adapters/abstract/transaction.rb:183:in `within_new_transaction'
/rails/activerecord/lib/active_record/connection_adapters/abstract/database_statements.rb:211:in `transaction'
/rails/activerecord/lib/active_record/transactions.rb:210:in `transaction'
/rails/activerecord/lib/active_record/transactions.rb:371:in `with_transaction_returning_status'
/rails/activerecord/lib/active_record/transactions.rb:303:in `save!'
/rails/activerecord/lib/active_record/suppressor.rb:42:in `save!'
app/controllers/posts_controller.rb:30:in `block in create'
/rails/actionpack/lib/action_controller/metal/mime_responds.rb:190:in `respond_to'
app/controllers/posts_controller.rb:29:in `create'
/rails/actionpack/lib/action_controller/metal/implicit_render.rb:4:in `send_action'
/rails/actionpack/lib/abstract_controller/base.rb:189:in `process_action'
/rails/actionpack/lib/action_controller/metal/rendering.rb:21:in `process_action'
/rails/actionpack/lib/abstract_controller/callbacks.rb:20:in `block in process_action'
/rails/activesupport/lib/active_support/callbacks.rb:117:in `call'
/rails/activesupport/lib/active_support/callbacks.rb:117:in `call'
/rails/activesupport/lib/active_support/callbacks.rb:558:in `block (2 levels) in compile'
/rails/activesupport/lib/active_support/callbacks.rb:501:in `call'
/rails/activesupport/lib/active_support/callbacks.rb:501:in `call'
/rails/activesupport/lib/active_support/callbacks.rb:90:in `run_callbacks'
/rails/actionpack/lib/abstract_controller/callbacks.rb:19:in `process_action'
/rails/actionpack/lib/action_controller/metal/rescue.rb:29:in `process_action'
/rails/actionpack/lib/action_controller/metal/instrumentation.rb:32:in `block in process_action'
/rails/activesupport/lib/active_support/notifications.rb:164:in `block in instrument'
/rails/activesupport/lib/active_support/notifications/instrumenter.rb:20:in `instrument'
/rails/activesupport/lib/active_support/notifications.rb:164:in `instrument'
/rails/actionpack/lib/action_controller/metal/instrumentation.rb:30:in `process_action'
/rails/actionpack/lib/action_controller/metal/params_wrapper.rb:249:in `process_action'
/rails/activerecord/lib/active_record/railties/controller_runtime.rb:18:in `process_action'
/rails/actionpack/lib/abstract_controller/base.rb:128:in `process'
/rails/actionview/lib/action_view/rendering.rb:30:in `process'
/rails/actionpack/lib/action_controller/metal.rb:194:in `dispatch'
/rails/actionpack/lib/action_controller/metal.rb:241:in `block in action'
/rails/actionpack/lib/action_dispatch/routing/route_set.rb:73:in `call'
/rails/actionpack/lib/action_dispatch/routing/route_set.rb:73:in `dispatch'
/rails/actionpack/lib/action_dispatch/routing/route_set.rb:42:in `serve'
/rails/actionpack/lib/action_dispatch/journey/router.rb:43:in `block in serve'
/rails/actionpack/lib/action_dispatch/journey/router.rb:30:in `each'
/rails/actionpack/lib/action_dispatch/journey/router.rb:30:in `serve'
/rails/actionpack/lib/action_dispatch/routing/route_set.rb:769:in `call'
rack (1.6.0) lib/rack/etag.rb:24:in `call'
rack (1.6.0) lib/rack/conditionalget.rb:38:in `call'
rack (1.6.0) lib/rack/head.rb:13:in `call'
/rails/actionpack/lib/action_dispatch/middleware/params_parser.rb:27:in `call'
/rails/actionpack/lib/action_dispatch/middleware/flash.rb:266:in `call'
rack (1.6.0) lib/rack/session/abstract/id.rb:225:in `context'
rack (1.6.0) lib/rack/session/abstract/id.rb:220:in `call'
/rails/actionpack/lib/action_dispatch/middleware/cookies.rb:560:in `call'
/rails/activerecord/lib/active_record/query_cache.rb:36:in `call'
/rails/activerecord/lib/active_record/connection_adapters/abstract/connection_pool.rb:642:in `call'
/rails/activerecord/lib/active_record/migration.rb:378:in `call'
/rails/actionpack/lib/action_dispatch/middleware/callbacks.rb:29:in `block in call'
/rails/activesupport/lib/active_support/callbacks.rb:86:in `run_callbacks'
/rails/actionpack/lib/action_dispatch/middleware/callbacks.rb:27:in `call'
/rails/actionpack/lib/action_dispatch/middleware/reloader.rb:73:in `call'
/rails/actionpack/lib/action_dispatch/middleware/remote_ip.rb:78:in `call'
/rails/actionpack/lib/action_dispatch/middleware/debug_exceptions.rb:47:in `call'
/Users/godfrey/.rvm/gems/ruby-2.2.2/bundler/gems/web-console-f5255e303d66/lib/web_console/middleware.rb:37:in `call'
/rails/actionpack/lib/action_dispatch/middleware/show_exceptions.rb:30:in `call'
/rails/railties/lib/rails/rack/logger.rb:38:in `call_app'
/rails/railties/lib/rails/rack/logger.rb:20:in `block in call'
/rails/activesupport/lib/active_support/tagged_logging.rb:70:in `block in tagged'
/rails/activesupport/lib/active_support/tagged_logging.rb:26:in `tagged'
/rails/activesupport/lib/active_support/tagged_logging.rb:70:in `tagged'
/rails/railties/lib/rails/rack/logger.rb:20:in `call'
/rails/actionpack/lib/action_dispatch/middleware/request_id.rb:25:in `call'
rack (1.6.0) lib/rack/methodoverride.rb:22:in `call'
rack (1.6.0) lib/rack/runtime.rb:18:in `call'
/rails/activesupport/lib/active_support/cache/strategy/local_cache_middleware.rb:28:in `call'
rack (1.6.0) lib/rack/lock.rb:17:in `call'
/rails/actionpack/lib/action_dispatch/middleware/static.rb:115:in `call'
rack (1.6.0) lib/rack/sendfile.rb:113:in `call'
/rails/railties/lib/rails/engine.rb:518:in `call'
/rails/railties/lib/rails/application.rb:165:in `call'
rack (1.6.0) lib/rack/lock.rb:17:in `call'
rack (1.6.0) lib/rack/content_length.rb:15:in `call'
rack (1.6.0) lib/rack/handler/webrick.rb:89:in `service'
/Users/godfrey/.rvm/rubies/ruby-2.2.2/lib/ruby/2.2.0/webrick/httpserver.rb:138:in `service'
/Users/godfrey/.rvm/rubies/ruby-2.2.2/lib/ruby/2.2.0/webrick/httpserver.rb:94:in `run'
/Users/godfrey/.rvm/rubies/ruby-2.2.2/lib/ruby/2.2.0/webrick/server.rb:294:in `block in start_thread'
/rails/activerecord/lib/active_record/querying.rb:49:in `find_by_sql'
/rails/activerecord/lib/active_record/statement_cache.rb:107:in `execute'
/rails/activerecord/lib/active_record/core.rb:192:in `find_by'
/rails/activerecord/lib/active_record/dynamic_matchers.rb:65:in `find_by_type_and_user_id'
/rails/activerecord/lib/active_record/dynamic_matchers.rb:19:in `method_missing'
app/models/user.rb:3:in `ensure_permission'
app/models/post.rb:5:in `ensure_author'
/rails/activesupport/lib/active_support/callbacks.rb:428:in `block in make_lambda'
/rails/activesupport/lib/active_support/callbacks.rb:164:in `call'
/rails/activesupport/lib/active_support/callbacks.rb:164:in `block (2 levels) in halting'
/rails/activesupport/lib/active_support/callbacks.rb:599:in `call'
/rails/activesupport/lib/active_support/callbacks.rb:599:in `block (2 levels) in default_terminator'
/rails/activesupport/lib/active_support/callbacks.rb:598:in `catch'
/rails/activesupport/lib/active_support/callbacks.rb:598:in `block in default_terminator'
/rails/activesupport/lib/active_support/callbacks.rb:165:in `call'
/rails/activesupport/lib/active_support/callbacks.rb:165:in `block in halting'
/rails/activesupport/lib/active_support/callbacks.rb:500:in `call'
/rails/activesupport/lib/active_support/callbacks.rb:500:in `block in call'
/rails/activesupport/lib/active_support/callbacks.rb:500:in `each'
/rails/activesupport/lib/active_support/callbacks.rb:500:in `call'
/rails/activesupport/lib/active_support/callbacks.rb:90:in `run_callbacks'
/rails/activerecord/lib/active_record/callbacks.rb:301:in `create_or_update'
/rails/activerecord/lib/active_record/persistence.rb:151:in `save!'
/rails/activerecord/lib/active_record/validations.rb:43:in `save!'
/rails/activerecord/lib/active_record/attribute_methods/dirty.rb:29:in `save!'
/rails/activerecord/lib/active_record/transactions.rb:303:in `block in save!'
/rails/activerecord/lib/active_record/transactions.rb:374:in `block in with_transaction_returning_status'
/rails/activerecord/lib/active_record/connection_adapters/abstract/database_statements.rb:211:in `block in transaction'
/rails/activerecord/lib/active_record/connection_adapters/abstract/transaction.rb:183:in `within_new_transaction'
/rails/activerecord/lib/active_record/connection_adapters/abstract/database_statements.rb:211:in `transaction'
/rails/activerecord/lib/active_record/transactions.rb:210:in `transaction'
/rails/activerecord/lib/active_record/transactions.rb:371:in `with_transaction_returning_status'
/rails/activerecord/lib/active_record/transactions.rb:303:in `save!'
/rails/activerecord/lib/active_record/suppressor.rb:42:in `save!'
app/controllers/posts_controller.rb:30:in `block in create'
/rails/actionpack/lib/action_controller/metal/mime_responds.rb:190:in `respond_to'
app/controllers/posts_controller.rb:29:in `create'
/rails/actionpack/lib/action_controller/metal/implicit_render.rb:4:in `send_action'
/rails/actionpack/lib/abstract_controller/base.rb:189:in `process_action'
/rails/actionpack/lib/action_controller/metal/rendering.rb:21:in `process_action'
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raise “zomg”
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class User < ActiveRecord::Base
has_many :permissions
has_many :posts
def ensure_permission(role)
raise "lolwut, how did I get here??"
permissions.find_by_type!(role)
end
end
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No content
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No content
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No content
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@current_user.name
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nil.name
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@current_user = User.find_by_id(session[:user_id])
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puts “zomg”
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class ApplicationController < ActionController::Base
def current_user
require "pp"
puts "ZOMG " * 1000
puts
puts "Stack Trace:"
puts caller
puts
puts "User ID: #{ session[:user_id].inspect }"
puts
puts "User:"
pp User.find_by_id(session[:user_id])
puts
puts "LOL " * 1000
@current_user ||= User.find_by_id(session[:user_id])
end
end
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puts caller
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require ‘pp’
pp some_object
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pp instance_values
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Debugger
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group :development, :test do
# Call 'byebug' anywhere in the code to stop execution
# and get a debugger console
gem 'byebug'
# Access an IRB console on exception pages or by using
# <%= console %> in views
gem 'web-console'
...
end
Gemfile
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class ApplicationController < ActionController::Base
def current_user
byebug
@current_user ||= User.find_by_id(session[:user_id])
end
end
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Started GET "/posts/1" for ::1 at 2015-04-20 14:22:58 -0400
Processing by PostsController#show as HTML
Parameters: {"id"=>"1"}
[1, 9] in /private/tmp/demo/app/controllers/application_controller.rb
1: class ApplicationController < ActionController::Base
2:
3: def current_user
4: byebug
5:
=> 6: @current_user ||= User.find_by_id(session[:user_id])
7: end
8:
9: end
(byebug)
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{ next, up, down, continue, ... }
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<%= console %>
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ActiveRecord::SubclassNotFound (The single-table inheritance...):
/rails/activerecord/lib/active_record/inheritance.rb:176:in `rescue in find_sti_class'
/rails/activerecord/lib/active_record/inheritance.rb:170:in `find_sti_class'
/rails/activerecord/lib/active_record/inheritance.rb:159:in `discriminate_class_for_record'
/rails/activerecord/lib/active_record/persistence.rb:67:in `instantiate'
/rails/activerecord/lib/active_record/querying.rb:50:in `block (2 levels) in find_by_sql'
/rails/activerecord/lib/active_record/result.rb:51:in `block in each'
/rails/activerecord/lib/active_record/result.rb:51:in `each'
/rails/activerecord/lib/active_record/result.rb:51:in `each'
/rails/activerecord/lib/active_record/querying.rb:50:in `map'
/rails/activerecord/lib/active_record/querying.rb:50:in `block in find_by_sql'
/rails/activesupport/lib/active_support/notifications/instrumenter.rb:20:in `instrument'
/rails/activerecord/lib/active_record/querying.rb:49:in `find_by_sql'
/rails/activerecord/lib/active_record/statement_cache.rb:107:in `execute'
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ActiveRecord::SubclassNotFound (The single-table inheritance...):
/rails/activerecord/lib/active_record/inheritance.rb:176:in `rescue in find_sti_class'
/rails/activerecord/lib/active_record/inheritance.rb:170:in `find_sti_class'
/rails/activerecord/lib/active_record/inheritance.rb:159:in `discriminate_class_for_record'
/rails/activerecord/lib/active_record/persistence.rb:67:in `instantiate'
/rails/activerecord/lib/active_record/querying.rb:50:in `block (2 levels) in find_by_sql'
/rails/activerecord/lib/active_record/result.rb:51:in `block in each'
/rails/activerecord/lib/active_record/result.rb:51:in `each'
/rails/activerecord/lib/active_record/result.rb:51:in `each'
/rails/activerecord/lib/active_record/querying.rb:50:in `map'
/rails/activerecord/lib/active_record/querying.rb:50:in `block in find_by_sql'
/rails/activesupport/lib/active_support/notifications/instrumenter.rb:20:in `instrument'
/rails/activerecord/lib/active_record/querying.rb:49:in `find_by_sql'
/rails/activerecord/lib/active_record/statement_cache.rb:107:in `execute'
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bundle open GEM_NAME
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gem pristine GEM_NAME
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Restart Rails server!
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spring stop
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export DISABLE_SPRING=1
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bundle open rails
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No content
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ActiveRecord::SubclassNotFound (The single-table inheritance...):
/rails/activerecord/lib/active_record/inheritance.rb:176:in `rescue in find_sti_class'
/rails/activerecord/lib/active_record/inheritance.rb:170:in `find_sti_class'
/rails/activerecord/lib/active_record/inheritance.rb:159:in `discriminate_class_for_record'
/rails/activerecord/lib/active_record/persistence.rb:67:in `instantiate'
/rails/activerecord/lib/active_record/querying.rb:50:in `block (2 levels) in find_by_sql'
/rails/activerecord/lib/active_record/result.rb:51:in `block in each'
/rails/activerecord/lib/active_record/result.rb:51:in `each'
/rails/activerecord/lib/active_record/result.rb:51:in `each'
/rails/activerecord/lib/active_record/querying.rb:50:in `map'
/rails/activerecord/lib/active_record/querying.rb:50:in `block in find_by_sql'
/rails/activesupport/lib/active_support/notifications/instrumenter.rb:20:in `instrument'
/rails/activerecord/lib/active_record/querying.rb:49:in `find_by_sql'
/rails/activerecord/lib/active_record/statement_cache.rb:107:in `execute'
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bundle open activerecord
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gem “rails”, path: “~/oss-forks/rails/”
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git stash ...
git reset ...
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git checkout master
git checkout 4-2-stable
git checkout v4.2.1
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require 'active_support/core_ext/hash/indifferent_access'
module ActiveRecord
# == Single table inheritance
#
# Active Record allows inheritance by storing the name of the class in a column that by
# default is named "type" (can be changed by overwriting Base.inheritance_column).
# This means that an inheritance looking like this:
#
# class Company < ActiveRecord::Base; end
# class Firm < Company; end
# class Client < Company; end
# class PriorityClient < Client; end
#
# When you do Firm.create(name: "37signals"), this record will be saved in
# the companies table with type = "Firm". You can then fetch this row again using
# Company.where(name: '37signals').first and it will return a Firm object.
#
# Be aware that because the type column is an attribute on the record every new
# subclass will instantly be marked as dirty and the type column will be included
# in the list of changed attributes on the record. This is different from non
# STI classes:
#
# Company.new.changed? # => false
# Firm.new.changed? # => true
# Firm.new.changes # => {"type"=>["","Firm"]}
#
# If you don't have a type column defined in your table, single-table inheritance won't
# be triggered. In that case, it'll work just like normal subclasses with no special magic
# for differentiating between them or reloading the right type with find.
#
# Note, all the attributes for all the cases are kept in the same table. Read more:
# http://www.martinfowler.com/eaaCatalog/singleTableInheritance.html
#
module Inheritance
extend ActiveSupport::Concern
included do
# Determines whether to store the full constant name including namespace when using STI.
class_attribute :store_full_sti_class, instance_writer: false
self.store_full_sti_class = true
end
module ClassMethods
# Determines if one of the attributes passed in is the inheritance column,
# and if the inheritance column is attr accessible, it initializes an
# instance of the given subclass instead of the base class.
def new(*args, &block)
if abstract_class? || self == Base
raise NotImplementedError, "#{self} is an abstract class and cannot be instantiated."
end
attrs = args.first
if subclass_from_attributes?(attrs)
subclass = subclass_from_attributes(attrs)
end
if subclass
subclass.new(*args, &block)
else
super
end
end
# Returns +true+ if this does not need STI type condition. Returns
# +false+ if STI type condition needs to be applied.
def descends_from_active_record?
if self == Base
false
elsif superclass.abstract_class?
superclass.descends_from_active_record?
else
superclass == Base || !columns_hash.include?(inheritance_column)
end
end
def finder_needs_type_condition? #:nodoc:
# This is like this because benchmarking justifies the strange :false stuff
:true == (@finder_needs_type_condition ||= descends_from_active_record? ? :false : :true)
end
# Returns the class descending directly from ActiveRecord::Base, or
# an abstract class, if any, in the inheritance hierarchy.
#
# If A extends AR::Base, A.base_class will return A. If B descends from A
# through some arbitrarily deep hierarchy, B.base_class will return A.
#
# If B < A and C < B and if A is an abstract_class then both B.base_class
# and C.base_class would return B as the answer since A is an abstract_class.
def base_class
unless self < Base
raise ActiveRecordError, "#{name} doesn't belong in a hierarchy descending from ActiveRecord"
end
if superclass == Base || superclass.abstract_class?
self
else
superclass.base_class
end
end
# Set this to true if this is an abstract class (see abstract_class?).
# If you are using inheritance with ActiveRecord and don't want child classes
# to utilize the implied STI table name of the parent class, this will need to be true.
# For example, given the following:
#
# class SuperClass < ActiveRecord::Base
# self.abstract_class = true
# end
# class Child < SuperClass
# self.table_name = 'the_table_i_really_want'
# end
#
#
# self.abstract_class = true is required to make Child<.find,.create, or any Arel method> use the_table_i_really_want instead of a table called super_classes
#
attr_accessor :abstract_class
# Returns whether this class is an abstract class or not.
def abstract_class?
defined?(@abstract_class) && @abstract_class == true
end
def sti_name
store_full_sti_class ? name : name.demodulize
end
protected
# Returns the class type of the record using the current module as a prefix. So descendants of
# MyApp::Business::Account would appear as MyApp::Business::AccountSubclass.
def compute_type(type_name)
if type_name.match(/^::/)
# If the type is prefixed with a scope operator then we assume that
# the type_name is an absolute reference.
ActiveSupport::Dependencies.constantize(type_name)
else
# Build a list of candidates to search for
candidates = []
name.scan(/::|$/) { candidates.unshift "#{$`}::#{type_name}" }
candidates << type_name
candidates.each do |candidate|
constant = ActiveSupport::Dependencies.safe_constantize(candidate)
return constant if candidate == constant.to_s
end
raise NameError.new("uninitialized constant #{candidates.first}", candidates.first)
end
end
private
# Called by +instantiate+ to decide which class to use for a new
# record instance. For single-table inheritance, we check the record
# for a +type+ column and return the corresponding class.
def discriminate_class_for_record(record)
if using_single_table_inheritance?(record)
find_sti_class(record[inheritance_column])
else
super
end
end
def using_single_table_inheritance?(record)
record[inheritance_column].present? && columns_hash.include?(inheritance_column)
end
def find_sti_class(type_name)
if store_full_sti_class
ActiveSupport::Dependencies.constantize(type_name)
else
compute_type(type_name)
end
rescue NameError
raise SubclassNotFound,
"The single-table inheritance mechanism failed to locate the subclass: '#{type_name}'. " +
"This error is raised because the column '#{inheritance_column}' is reserved for storing the class in case of inheritance. " +
"Please rename this column if you didn't intend it to be used for storing the inheritance class " +
"or overwrite #{name}.inheritance_column to use another column for that information."
end
def type_condition(table = arel_table)
sti_column = table[inheritance_column]
sti_names = ([self] + descendants).map(&:sti_name)
sti_column.in(sti_names)
end
# Detect the subclass from the inheritance column of attrs. If the inheritance column value
# is not self or a valid subclass, raises ActiveRecord::SubclassNotFound
# If this is a StrongParameters hash, and access to inheritance_column is not permitted,
# this will ignore the inheritance column and return nil
def subclass_from_attributes?(attrs)
attribute_names.include?(inheritance_column) && attrs.is_a?(Hash)
end
def subclass_from_attributes(attrs)
subclass_name = attrs.with_indifferent_access[inheritance_column]
if subclass_name.present? && subclass_name != self.name
subclass = subclass_name.safe_constantize
unless descendants.include?(subclass)
raise ActiveRecord::SubclassNotFound.new("Invalid single-table inheritance type: #{subclass_name} is not a subclass of #{name}")
end
subclass
end
end
end
def initialize_dup(other)
super
ensure_proper_type
end
private
def initialize_internals_callback
super
ensure_proper_type
end
# Sets the attribute used for single table inheritance to this class name if this is not the
# ActiveRecord::Base descendant.
# Considering the hierarchy Reply < Message < ActiveRecord::Base, this makes it possible to
# do Reply.new without having to set Reply[Reply.inheritance_column] = "Reply" yourself.
# No such attribute would be set for objects of the Message class in that example.
def ensure_proper_type
klass = self.class
if klass.finder_needs_type_condition?
write_attribute(klass.inheritance_column, klass.sti_name)
end
end
end
end
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Take a deep breath.
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Stay laser-focused.
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Ignore everything else.
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1. What does this method do?
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1. What does this method do?
2. What are the inputs?
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1. What does this method do?
2. What are the inputs?
3. What is expected to happen?
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1. What does this method do?
2. What are the inputs?
3. What is expected to happen?
4. Did that happen?
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Follow the breadcrumbs.
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module ActiveRecord
module Inheritance
module ClassMethods
def find_sti_class(type_name)
if store_full_sti_class
ActiveSupport::Dependencies.constantize(type_name)
else
compute_type(type_name)
end
rescue NameError
raise SubclassNotFound, "The single-table inheritance mechanism..."
end
end
end
end
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module ActiveRecord
module Inheritance
module ClassMethods
def find_sti_class(type_name)
if store_full_sti_class
ActiveSupport::Dependencies.constantize(type_name)
else
compute_type(type_name)
end
rescue NameError
raise SubclassNotFound, "The single-table inheritance mechanism..."
end
end
end
end
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module ActiveRecord
module Inheritance
module ClassMethods
def find_sti_class(type_name)
if store_full_sti_class
ActiveSupport::Dependencies.constantize(type_name)
else
compute_type(type_name)
end
rescue NameError
raise SubclassNotFound, "The single-table inheritance mechanism..."
end
end
end
end
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module ActiveRecord
module Inheritance
module ClassMethods
def find_sti_class(type_name)
if store_full_sti_class
ActiveSupport::Dependencies.constantize(type_name)
else
compute_type(type_name)
end
rescue NameError
raise SubclassNotFound, "The single-table inheritance mechanism..."
end
end
end
end
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module ActiveRecord
module Inheritance
module ClassMethods
def find_sti_class(type_name)
if store_full_sti_class
ActiveSupport::Dependencies.constantize(type_name)
else
compute_type(type_name)
end
rescue NameError
raise SubclassNotFound, "The single-table inheritance mechanism..."
end
end
end
end
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module ActiveRecord
module Inheritance
module ClassMethods
def find_sti_class(type_name)
if store_full_sti_class
ActiveSupport::Dependencies.constantize(type_name)
else
compute_type(type_name)
end
rescue NameError
raise SubclassNotFound, "The single-table inheritance mechanism..."
end
end
end
end
Where is this defined?
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{ Terminal, Editor, Github } Search
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module ActiveRecord
module Inheritance
module ClassMethods
def find_sti_class(type_name)
if store_full_sti_class
ActiveSupport::Dependencies.constantize(type_name)
else
byebug
compute_type(type_name)
end
rescue NameError
raise SubclassNotFound, "The single-table inheritance mechanism..."
end
end
end
end
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method(:compute_type)
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method(:compute_type).source_location
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method(:compute_type).owner
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gem “method_source”
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method(:compute_type).source
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method(:compute_type).comment
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# Returns the class type of the record using the current module as a prefix. So descendants of
# MyApp::Business::Account would appear as MyApp::Business::AccountSubclass.
def compute_type(type_name)
if type_name.match(/^::/)
# If the type is prefixed with a scope operator then we assume that
# the type_name is an absolute reference.
ActiveSupport::Dependencies.constantize(type_name)
else
# Build a list of candidates to search for
candidates = []
name.scan(/::|$/) { candidates.unshift "#{$`}::#{type_name}" }
candidates << type_name
candidates.each do |candidate|
constant = ActiveSupport::Dependencies.safe_constantize(candidate)
return constant if candidate == constant.to_s
end
raise NameError.new("uninitialized constant #{candidates.first}", candidates.first)
end
end
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# Returns the class type of the record using the current module as a prefix. So descendants of
# MyApp::Business::Account would appear as MyApp::Business::AccountSubclass.
def compute_type(type_name)
if type_name.match(/^::/)
# If the type is prefixed with a scope operator then we assume that
# the type_name is an absolute reference.
ActiveSupport::Dependencies.constantize(type_name)
else
# Build a list of candidates to search for
candidates = []
name.scan(/::|$/) { candidates.unshift "#{$`}::#{type_name}" }
candidates << type_name
candidates.each do |candidate|
constant = ActiveSupport::Dependencies.safe_constantize(candidate)
return constant if candidate == constant.to_s
end
raise NameError.new("uninitialized constant #{candidates.first}", candidates.first)
end
end
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# Returns the class type of the record using the current module as a prefix. So descendants of
# MyApp::Business::Account would appear as MyApp::Business::AccountSubclass.
def compute_type(type_name)
if type_name.match(/^::/)
# If the type is prefixed with a scope operator then we assume that
# the type_name is an absolute reference.
ActiveSupport::Dependencies.constantize(type_name)
else
# Build a list of candidates to search for
candidates = []
name.scan(/::|$/) { candidates.unshift "#{$`}::#{type_name}" }
candidates << type_name
candidates.each do |candidate|
constant = ActiveSupport::Dependencies.safe_constantize(candidate)
return constant if candidate == constant.to_s
end
raise NameError.new("uninitialized constant #{candidates.first}", candidates.first)
end
end
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git log inheritance.rb
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git blame inheritance.rb
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ceb33f84 (Jon Leighton # MyApp::Business::Account would appear as MyApp::Business::AccountSubclass.
ceb33f84 (Jon Leighton def compute_type(type_name)
ceb33f84 (Jon Leighton if type_name.match(/^::/)
ceb33f84 (Jon Leighton # If the type is prefixed with a scope operator then we assume that
ceb33f84 (Jon Leighton # the type_name is an absolute reference.
ceb33f84 (Jon Leighton ActiveSupport::Dependencies.constantize(type_name)
ceb33f84 (Jon Leighton else
ceb33f84 (Jon Leighton # Build a list of candidates to search for
ceb33f84 (Jon Leighton candidates = []
ceb33f84 (Jon Leighton name.scan(/::|$/) { candidates.unshift "#{$`}::#{type_name}" }
ceb33f84 (Jon Leighton candidates << type_name
ceb33f84 (Jon Leighton
ceb33f84 (Jon Leighton candidates.each do |candidate|
c965de39 (Arthur Neves constant = ActiveSupport::Dependencies.safe_constantize(candidate)
c965de39 (Arthur Neves return constant if candidate == constant.to_s
ceb33f84 (Jon Leighton end
ceb33f84 (Jon Leighton
bea44cba (Chulki Lee raise NameError.new("uninitialized constant #{candidates.first}", candidates.first)
ceb33f84 (Jon Leighton end
ceb33f84 (Jon Leighton end
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git show ceb33f84
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ceb33f8 Split out most of the AR::Base code into separate modules :cake: (Jon Leighton, 3 years, 4 months ago)
diff --git a/activerecord/lib/active_record.rb b/activerecord/lib/active_record.rb
index 92f3666..de73715 100644
--- a/activerecord/lib/active_record.rb
+++ b/activerecord/lib/active_record.rb
@@ -39,6 +39,7 @@ module ActiveRecord
autoload :Aggregations
autoload :Associations
autoload :AttributeMethods
+ autoload :AttributeAssignment
autoload :AutosaveAssociation
autoload :Relation
@@ -57,27 +58,37 @@ module ActiveRecord
autoload :Base
autoload :Callbacks
autoload :CounterCache
+ autoload :DefaultScope
+ autoload :DynamicMatchers
autoload :DynamicFinderMatch
autoload :DynamicScopeMatch
+ autoload :Explain
+ autoload :IdentityMap
+ autoload :Inheritance
+ autoload :Integration
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git blame ceb33f84^ inheritance.rb
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git blame ceb33f84^ inheritance.rb
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lame ceb33f84^ inheritance
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eb33f84^ inher
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https://github.com/chancancode/blame_parent
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Isolating the problem
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rails new --dev zomg
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Bug Report Template
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guides/bug_report_templates/active_record_gem.rb
Models, database
guides/bug_report_templates/action_controller_gem.rb
Controllers, routing, etc
guides/bug_report_templates/generic_gem.rb
Everything else
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Getting help
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...or you can probably Just Fix It™ ;)
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ಠ_ಠ
I want my money back.
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Right
You already know this stuff!
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Rails
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Ruby
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Ruby
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leg•a•cy code |ˈlegəsē kōd| noun
code you didn’t write (this morning)
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Community Office Hour
Wednesday, during happy hour
Heroku booth
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Breaking down the barrier
Demystifying contributing to Rails
Eileen M. Uchitelle
@ eileencodes
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@chancancode
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