Clearance
=========
[](http://travis-ci.org/thoughtbot/clearance?branch=master)
[](https://codeclimate.com/github/thoughtbot/clearance)
[](https://gemnasium.com/thoughtbot/clearance)
Rails authentication with email & password.
Clearance was extracted out of [Airbrake](http://airbrake.io/). It is intended
to be small, simple, and well-tested. It is intended to be easy to override
defaults.
Use [GitHub Issues](https://github.com/thoughtbot/clearance/issues) for help.
Read [CONTRIBUTING.md](/CONTRIBUTING.md) to contribute.
Install
-------
Clearance is a Rails engine tested against Rails `>= 3.2` and Ruby `>= 1.9.3`.
It works with Rails 4 and Ruby 2.
Include the gem in your Gemfile:
```ruby
gem 'clearance'
```
Bundle:
bundle --binstubs
Make sure the development database exists. Then, run the generator:
rails generate clearance:install
The generator:
* inserts `Clearance::User` into your `User` model
* inserts `Clearance::Controller` into your `ApplicationController`
* creates a migration that either creates a users table or adds only missing
columns
Then, follow the instructions output from the generator.
Use Clearance [0.8.8](https://github.com/thoughtbot/clearance/tree/v0.8.8) for
Rails 2 apps.
Use Clearance [0.16.3](http://rubygems.org/gems/clearance/versions/0.16.3) for
Ruby 1.8.7 apps.
Configure
---------
Override any of these defaults in `config/initializers/clearance.rb`:
```ruby
Clearance.configure do |config|
config.cookie_domain = '.example.com'
config.cookie_expiration = lambda { |cookies| 1.year.from_now.utc }
config.cookie_path = '/'
config.httponly = false
config.mailer_sender = 'reply@example.com'
config.password_strategy = Clearance::PasswordStrategies::BCrypt
config.redirect_url = '/'
config.secure_cookie = false
config.sign_in_guards = []
config.user_model = User
end
```
Use
---
Use `current_user`, `signed_in?`, and `signed_out?` in controllers, views, and
helpers. For example:
```haml
- if signed_in?
= current_user.email
= link_to 'Sign out', sign_out_path, method: :delete
- else
= link_to 'Sign in', sign_in_path
```
To authenticate a user elsewhere than `sessions/new` (like in an API):
```ruby
User.authenticate 'email@example.com', 'password'
```
When a user resets their password, Clearance delivers them an email. So, you
should change the `mailer_sender` default, used in the email's "from" header:
```ruby
Clearance.configure do |config|
config.mailer_sender = 'reply@example.com'
end
```
Use `authorize` to control access in controllers:
```ruby
class ArticlesController < ApplicationController
before_filter :authorize
def index
current_user.articles
end
end
```
Or, you can authorize users in `config/routes.rb`:
```ruby
Blog::Application.routes.draw do
constraints Clearance::Constraints::SignedIn.new { |user| user.admin? } do
root to: 'admin'
end
constraints Clearance::Constraints::SignedIn.new do
root to: 'dashboard'
end
constraints Clearance::Constraints::SignedOut.new do
root to: 'marketing'
end
end
```
Clearance adds its session to the Rack environment hash so middleware and other
Rack applications can interact with it:
```ruby
class Bubblegum::Middleware
def initialize(app)
@app = app
end
def call(env)
if env[:clearance].signed_in?
env[:clearance].current_user.bubble_gum
end
@app.call(env)
end
end
```
Overriding routes
-----------------
See [config/routes.rb](/config/routes.rb) for the default behavior.
To override a Clearance route, redefine it:
```ruby
resource :session, controller: 'sessions'
```
Overriding controllers
----------------------
See [app/controllers/clearance](/app/controllers/clearance) for the default
behavior.
To override a Clearance controller, subclass it:
```ruby
class PasswordsController < Clearance::PasswordsController
class SessionsController < Clearance::SessionsController
class UsersController < Clearance::UsersController
```
Then, override public methods:
passwords#create
passwords#edit
passwords#new
passwords#update
sessions#create
sessions#destroy
sessions#new
users#create
users#new
Or, override private methods:
passwords#find_user_by_id_and_confirmation_token
passwords#find_user_for_create
passwords#find_user_for_edit
passwords#find_user_for_update
passwords#flash_failure_after_create
passwords#flash_failure_after_update
passwords#flash_failure_when_forbidden
passwords#forbid_missing_token
passwords#forbid_non_existent_user
passwords#url_after_create
passwords#url_after_update
sessions#flash_failure_after_create
sessions#url_after_create
sessions#url_after_destroy
users#flash_failure_after_create
users#url_after_create
users#user_from_params
All of these controller methods redirect to `'/'` by default:
passwords#url_after_update
sessions#url_after_create
users#url_after_create
application#url_after_denied_access_when_signed_in
To override them all at once, change the global configuration:
```ruby
Clearance.configure do |config|
config.redirect_url = '/overriden'
end
```
Overriding translations
-----------------------
All flash messages and email subject lines are stored in
[i18n translations](http://guides.rubyonrails.org/i18n.html).
Override them like any other translation.
See [config/locales/clearance.en.yml](/config/locales/clearance.en.yml) for the
default behavior.
Overriding views
----------------
See [app/views](/app/views) for the default behavior.
To override a view, create your own:
app/views/clearance_mailer/change_password.html.erb
app/views/passwords/create.html.erb
app/views/passwords/edit.html.erb
app/views/passwords/new.html.erb
app/views/sessions/_form.html.erb
app/views/sessions/new.html.erb
app/views/users/_form.html.erb
app/views/users/new.html.erb
There is a shortcut to copy all Clearance views into your app:
rails generate clearance:views
Overriding the model
--------------------
See [lib/clearance/user.rb](/lib/clearance/user.rb) for the default behavior.
To override the model, redefine public methods:
User.authenticate(email, password)
User#forgot_password!
User#reset_remember_token!
User#update_password(new_password)
Or, redefine private methods:
User#email_optional?
User#generate_confirmation_token
User#generate_remember_token
User#normalize_email
User#password_optional?
Overriding the password strategy
--------------------------------
By default, Clearance uses BCrypt encryption of the user's password.
See
[lib/clearance/password_strategies/bcrypt.rb](/lib/clearance/password_strategies/bcrypt.rb)
for the default behavior.
Change your password strategy in `config/initializers/clearance.rb:`
```ruby
Clearance.configure do |config|
config.password_strategy = Clearance::PasswordStrategies::SHA1
end
```
Clearance provides the following strategies:
```ruby
Clearance::PasswordStrategies::BCrypt
Clearance::PasswordStrategies::BCryptMigrationFromSHA1
Clearance::PasswordStrategies::Blowfish
Clearance::PasswordStrategies::SHA1
```
The previous default password strategy was SHA1.
Switching password strategies may cause your existing users to not be able to sign in.
If you have an existing app that used the old `SHA1` strategy and you want to
stay with SHA1, use
[Clearance::PasswordStrategies::SHA1](/lib/clearance/password_strategies/sha1.rb).
If you have an existing app that used the old `SHA1` strategy and you want to
switch to BCrypt transparently, use
[Clearance::PasswordStrategies::BCryptMigrationFromSHA1](/lib/clearance/password_strategies/bcrypt_migration_from_sha1.rb).
The SHA1 and Blowfish password strategies require an additional `salt` column in
the `users` table. Run this migration before switching to SHA or Blowfish:
```ruby
class AddSaltToUsers < ActiveRecord::Migration
def change
add_column :users, :salt, :string, limit: 128
end
end
```
You can write a custom password strategy that has two instance methods.
In your `authenticated?` method, encrypt the password with your desired
strategy, and then compare it to the `encrypted_password` that is provided by
Clearance.
```ruby
module CustomPasswordStrategy
def authenticated?(password)
encrypted_password == encrypt(password)
end
def password=(new_password)
end
private
def encrypt
# your encryption strategy
end
end
Clearance.configure do |config|
config.password_strategy = CustomPasswordStrategy
end
```
Deliver password reset email in a background job
------------------------------------------------
Clearance has one mailer. It is used to reset the user's password.
To deliver it in a background job using a queue system like [Delayed
Job](https://github.com/collectiveidea/delayed_job), subclass
`Clearance::PasswordsController` and define the behavior you need in its
`deliver_email` method:
```ruby
class PasswordsController < Clearance::PasswordsController
def deliver_email(user)
ClearanceMailer.delay.change_password(user)
end
end
```
Then, override the route:
```ruby
resources :passwords, only: [:create]
```
Using the SignInGuard stack
-------------------
`SignInGuard`s offer fine-grained control over the process of
signing in a user. Each guard is run in order and hands the session off to
the next guard in the stack.
A `SignInGuard` is an object that responds to `call`. It is initialized with a
session and the current stack.
On success, a guard should call the next guard or return `SuccessStatus.new` if
you don't want any subsequent guards to run.
On failure, a guard should call `FailureStatus.new(failure_message)`. It can
provide a message explaining the failure.
For convenience, a [SignInGuard](lib/clearance/sign_in_guard.rb) class has been
provided and can be inherited from. The convenience class provides a few methods
to help make writing guards simple: `success`, `failure`, `next_guard`,
`signed_in?`, and `current_user`.
Here's an example custom guard to handle email confirmation:
```ruby
Clearance.configure do |config|
config.sign_in_guards = [EmailConfirmationGuard]
end
```
```ruby
class EmailConfirmationGuard < Clearance::SignInGuard
def call
if unconfirmed?
failure("You must confirm your email address.")
else
next_guard
end
end
def unconfirmed?
signed_in? && !current_user.confirmed_at
end
end
```
Optional feature specs
----------------------
You can generate feature specs to help prevent regressions in Clearance's
integration with your Rails app over time.
Edit your `Gemfile` to include the dependencies:
```ruby
gem 'capybara', '~> 2.0'
gem 'factory_girl_rails', '~> 4.2'
gem 'rspec-rails', '~> 2.13'
```
Generate RSpec files:
rails generate rspec:install
Generate Clearance specs:
rails generate clearance:specs
Run the specs:
rake
Testing authorized controller actions
-------------------------------------
To test controller actions that are protected by `before_filter :authorize`,
include Clearance's test helpers and matchers in `spec/support/clearance.rb` or
`test/test_helper.rb`:
```ruby
require 'clearance/testing'
```
This will make `Clearance::Controller` methods work in your controllers
during functional tests and provide access to helper methods like:
sign_in
sign_in_as(user)
sign_out
And matchers like:
deny_access
Example:
```ruby
context 'a guest' do
before do
get :show
end
it { should deny_access }
end
context 'a user' do
before do
sign_in
get :show
end
it { should respond_with(:success) }
end
```
You may want to customize the tests:
```ruby
it { should deny_access }
it { should deny_access(flash: 'Denied access.') }
it { should deny_access(redirect: sign_in_url) }
```
Faster tests
------------
Clearance includes middleware that avoids wasting time spent visiting, loading,
and submitting the sign in form. It instead signs in the designated
user directly. The speed increase can be
[substantial](http://robots.thoughtbot.com/post/37907699673/faster-tests-sign-in-through-the-back-door).
Configuration:
```ruby
# config/environments/test.rb
MyRailsApp::Application.configure do
# ...
config.middleware.use Clearance::BackDoor
# ...
end
```
Usage:
```ruby
visit root_path(as: user)
```
Credits
-------
Clearance is maintained by [thoughtbot, inc](http://thoughtbot.com/community)
and [contributors](/thoughtbot/clearance/graphs/contributors) like you. Thank you!
License
-------
Clearance is copyright © 2009-2013 thoughtbot. It is free software, and may be
redistributed under the terms specified in the `LICENSE` file.
The names and logos for thoughtbot are trademarks of thoughtbot, inc.