FeatureToggles
This gem provides a mechanism for pending features that take longer than a single release cycle. The basic idea is to have a configuration file that defines a bunch of toggles for various features you have pending. The running application then uses these toggles in order to decide whether or not to show the new feature.
Installation
Add this line to your application’s Gemfile:
ruby
gem "feature_toggles"
And then execute:
$ bundle
Or install it yourself as:
$ gem install feature_toggles
Framework-agnostic usage
Features could be defined dynamically
```ruby features = FeatureToggles.build do # define env var prefix to enable features # globally by passing MY_PREFIX_BAR=1 env “MY_PREFIX”
feature :bar do user.can_bar? end
feature :foo do |user: nil| !user.nil? && user.can_foo? end end
features.enabled?(:bar) features.enabled?(:bar, user: user) features.for(user: user).enabled?(:foo) ```
or loaded from files
ruby
features = FeatureToggles.build(["/path/to/features.rb"])
Rails usage
This is step-by-step guide to add feature_toggles to Rails application.
Step 0. (optional) Add features to User model
NOTE: This is not the part of this gem–you can model you per-user features settings differently.
ruby
class AddFeaturesToUsers < ActiveRecord::Migration
def change
# we use a `features` array column to store user's active features
add_column :users, :features, :string, array: true, default: []
end
end
Step 1. Define features
Features from file <rails-root-or-engine>/config/features.rb are loaded by convention.
```ruby # config/features.rb env “FEATURE”
feature :chat do |user: nil| user&.features.include?(“chat”) end ```
Features will be available at Rails.features after the end of application initialization.
Step 2. Add current_features helper and use it.
```ruby class ApplicationController < ActionController::Base # … helper_method :current_features
def current_features Rails.features.for(user: current_user) end end ```
Step 3. Use current_features.
For example, in your navigation template:
```erb
-
<% if current_features.enabled?(:chat) %>
- Chat <% end %>
```
Or in your controller:
ruby
class ChatController < ApplicationController
def index
unless current_features.enabled?(:chat)
return render template: "comming_soon"
end
end
end
Metadata
You can add arbitrary metadata to features:
ruby
feature :manual_quantity_backsync, icon: :updated, description: "Manual quantity sync for imported products" do |user: nil|
!!user&.features&.fetch("manual_quantity_backsync", false)
end
That metadata can be later programmatically accessed and exposed into admin panels, API documentation, etc.
ruby
Rails.features.first.metadata
# => { icon: :updated, description: "Manual quantity sync for imported products" }
Development
After checking out the repo, run bin/setup to install dependencies. Then, run rake spec to run the tests. You can also run bin/console for an interactive prompt that will allow you to experiment.
To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version number in version.rb, and then run bundle exec rake release, which will create a git tag for the version, push git commits and tags, and push the .gem file to rubygems.org.
Contributing
Bug reports and pull requests are welcome on GitHub at https://github.com/bibendi/feature_toggles. This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the Contributor Covenant code of conduct.
License
The gem is available as open source under the terms of the MIT License.
Code of Conduct
Everyone interacting in the FeatureToggles project’s codebases, issue trackers, chat rooms and mailing lists is expected to follow the code of conduct.