Chanko Hacking Guide

https://github.com/cookpad/chanko

Transcript

1. CHG
   Chanko Hacking Guide
   @r7kamura
   

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2. 1. README.md
   2. chanko.gemspec
   3. lib/chanko.rb
   4. lib/chanko/railtie.rb
   5. lib/chanko/invoker.rb
   6. lib/chanko/loader.rb
   7. lib/chanko/function.rb
   

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3. README.md
   Chanko
   !
   Chanko provides a simple framework for rapidly and safely
   prototyping new features in your production Rails app, and
   exposing these prototypes to specified segments of your user base.
   !
   With Chanko, you can release many features concurrently and
   manage target users independently. When any errors are raised from
   chanko's features, it will be automatically hidden and fallback to its
   normal behavior.
   

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4. README.md
   = invoke(:unit_name, :function_name) do
   # fallback …
   

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5. rails >= 3.0.10
   chanko.gemspec
   

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6. Bundler.require
   Loads all Gems listed in Gemfile.
   Open your config/application.rb
   to see the real example.
   !
   # example
   Bundler.require(:default, Rails.env)
   

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7. require "action_controller"
   require "action_view"
   require "active_record"
   require "active_support/all"
   require "rails"
   require "chanko/active_if"
   require "chanko/config"
   require "chanko/controller"
   require "chanko/exception_handler"
   require "chanko/function"
   require "chanko/helper"
   require "chanko/invoker"
   require "chanko/loader"
   require "chanko/logger"
   require "chanko/railtie"
   require "chanko/unit"
   require "chanko/unit_proxy"
   require "chanko/unit_proxy_provider"
   lib/chanko.rb
   external
   internal
   

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8. Rails::Railtie
   Railtie is the core of the Rails framework and
   provides several hooks to extend Rails and/or
   modify the initialization process.
   !
   class MyRailtie < Rails::Railtie
   initializer "my_initializer_name" do
   # some initialization behavior
   end
   end
   

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9. Rails Init Process
   1. `rails s`
   2. bin/rails
   3. rails/commands/server … or using unicorn
   4. config.ru
   5. config/application.rb
   6. Bundler.require
   7. My::Application.initialize!
   8. initializers.tsort_each…
   9. run My::Application
   

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10. initializer "chanko" do
    ActionController::Base.include Controller
    ActionController::Base.include Invoker
    ActionController::Base.include UnitProxyProvider
    ActionView::Base.include Helper
    ActionView::Base.include Invoker
    ActionView::Base.include UnitProxyProvider
    end
    lib/chanko/railtie.rb
    

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11. .invoke(:x, :y)
    1. find a module named “X”
    2. find a function named “y” from “X”
    3. stack local variables
    4. call “y”
    5. unstack local variables
    6. call fallback block if any error occurred
    lib/chanko/invoker.rb
    

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12. Loader.load(name)
    1. autoload_paths << app/extensions/#{name}
    2. name.camelize.constantize
    3. rescue Exception
    lib/chanko/loader.rb
    

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13. AS::Dependencies
    1. Register auto load path
    2. Find module if const_missing occurred
    3. Clear loaded modules if any file changed
    

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14. lib/chanko/invoker.rb
    view.invoke(:x, :y)
    Loader.load(:x)
    AS::Dependencies
    “X”.constantize
    Loader.cache
    .clear
    in each request
    in development
    

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15. lib/chanko/invoker.rb
    view.invoke(:x, :y)
    X.find_function(view, :y)
    function.invoke(view)
    view.instance_eval
    X.scopes[view][:y]
    module X
    scopes(:view) {
    function(:y) {
    …
    }
    }
    end
    function.active?
    

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16. lib/chanko/function.rb
    instance
    _eval
    decoration
    exception handler
    view path
    stack
    unit stack
    fallback stack
    

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17. Thank you
    github.com/cookpad/chanko
    

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