Chanko

http://cookpad.github.io/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.

• Ruby >= 3.0.0
• Rails >= 6.1.0

Add to your Gemfile.

gem "chanko"

Chanko provides a generator to create templates of an unit.

$ rails generate chanko:unit example_unit
      create  app/units/example_unit
      create  app/units/example_unit/example_unit.rb
      create  app/units/example_unit/views/.gitkeep
      create  app/units/example_unit/images/.gitkeep
      create  app/units/example_unit/javascripts/.gitkeep
      create  app/units/example_unit/stylesheets/.gitkeep
      create  app/assets/images/units/example_unit
      create  app/assets/javascripts/units/example_unit
      create  app/assets/stylesheets/units/example_unit

You can invoke the logics defined in your units via invoke and unit methods. In controller class context, unit_action utility is also provided. The block passed to invoke is a fallback executed if any problem occurs in invoking.

# app/controllers/users_controller.rb
class UsersController < ApplicationController
  unit_action :example_unit, :show

  def index
    invoke(:example_unit, :index) do
      @users = User.all
    end
  end
end

-# app/views/examples/index.html.slim
= unit.helper_method
= invoke(:example_unit, :render_example)

You can see the real example of an unit module file.

You can define your MVC code here.

# app/units/example_unit/example_unit.rb
module ExampleUnit
  include Chanko::Unit
  ...
end

This block is used to decide if this unit is active or not. context is the receiver object of invoke. options is passed via invoke(:foo, :bar, :active_if_options => { ... }). By default, this is set as active_if { true }.

active_if do |context, options|
  true
end

By default, any error raised in production env is ignored. raise_error is used to force an unit to raise up errors occured in invoking. You can force all units to raise up errors by Config.raise_error = true.

raise_error

In controller or view context, you can call functions defined by function via invoke(:example_unit, :function_name).

scope(:controller) do
  function(:show) do
    @user = User.find(params[:id])
  end

  function(:index) do
    @users = User.active
  end
end

In version 2 and earlier, Chanko extended Rails' search path to include the views path of the unit. This functionality has been discontinued. To maintain the views path under the unit, you will need to manually create a symbolic link in app/views/units to access it.

You can call methods defined by shared in invoking.

shared(:hello) do |world|
  "Hello, #{world}"
end

You can call helpers in view via unit proxy like unit.helper_method.

helpers do
  def helper_method
    "helper method"
  end
end

https://github.com/cookpad/chanko/tree/master/spec/dummy
Chanko provides an example rails application in spec/dummy directory.

$ git clone git@github.com:cookpad/chanko.git
$ cd chanko/spec/dummy
$ bundle install
$ bundle exec rake db:create db:migrate
$ rails s
$ open http://localhost:3000