https://github.com/nebulab/simple_command
A simple, standardized way to build and use Service Objects (aka Commands) in Ruby
https://github.com/nebulab/simple_command
ruby service-object
Last synced: 8 months ago
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A simple, standardized way to build and use Service Objects (aka Commands) in Ruby
- Host: GitHub
- URL: https://github.com/nebulab/simple_command
- Owner: nebulab
- License: mit
- Created: 2014-12-23T11:28:33.000Z (about 11 years ago)
- Default Branch: master
- Last Pushed: 2023-09-11T04:27:30.000Z (over 2 years ago)
- Last Synced: 2025-05-10T12:09:13.492Z (8 months ago)
- Topics: ruby, service-object
- Language: Ruby
- Homepage: http://nebulab.it
- Size: 52.7 KB
- Stars: 630
- Watchers: 31
- Forks: 54
- Open Issues: 6
-
Metadata Files:
- Readme: README.md
- License: LICENSE.txt
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README
[](https://codeclimate.com/github/nebulab/simple_command)
# SimpleCommand
A simple, standardized way to build and use _Service Objects_ (aka _Commands_) in Ruby
## Requirements
* Ruby 2.6+
## Installation
Add this line to your application's Gemfile:
```ruby
gem 'simple_command'
```
And then execute:
$ bundle
Or install it yourself as:
$ gem install simple_command
## Usage
Here's a basic example of a command that authenticates a user
```ruby
# define a command class
class AuthenticateUser
# put SimpleCommand before the class' ancestors chain
prepend SimpleCommand
include ActiveModel::Validations
# optional, initialize the command with some arguments
def initialize(email, password)
@email = email
@password = password
end
# mandatory: define a #call method. its return value will be available
# through #result
def call
if user = User.find_by(email: @email)&.authenticate(@password)
return user
else
errors.add(:base, :failure)
end
nil
end
end
```
in your locale file
```yaml
# config/locales/en.yml
en:
activemodel:
errors:
models:
authenticate_user:
failure: Wrong email or password
```
Then, in your controller:
```ruby
class SessionsController < ApplicationController
def create
# initialize and execute the command
# NOTE: `.call` is a shortcut for `.new(args).call`
command = AuthenticateUser.call(session_params[:email], session_params[:password])
# check command outcome
if command.success?
# command#result will contain the user instance, if found
session[:user_token] = command.result.secret_token
redirect_to root_path
else
flash.now[:alert] = t(command.errors.full_messages.to_sentence)
render :new
end
end
private
def session_params
params.require(:session).permit(:email, :password)
end
end
```
## Test with Rspec
Make the spec file `spec/commands/authenticate_user_spec.rb` like:
```ruby
describe AuthenticateUser do
subject(:context) { described_class.call(username, password) }
describe '.call' do
context 'when the context is successful' do
let(:username) { 'correct_user' }
let(:password) { 'correct_password' }
it 'succeeds' do
expect(context).to be_success
end
end
context 'when the context is not successful' do
let(:username) { 'wrong_user' }
let(:password) { 'wrong_password' }
it 'fails' do
expect(context).to be_failure
end
end
end
end
```
## Contributing
1. Fork it ( https://github.com/nebulab/simple_command/fork )
2. Create your feature branch (`git checkout -b my-new-feature`)
3. Commit your changes (`git commit -am 'Add some feature'`)
4. Push to the branch (`git push origin my-new-feature`)
5. Create a new Pull Request