Clearance

Rails authentication with email & password.

Clearance is intended to be small, simple, and well-tested. It has opinionated defaults but is intended to be easy to override.

Please use GitHub Issues to report bugs. If you have a question about the library, please use the clearance tag on Stack Overflow. This tag is monitored by contributors.

Getting Started

Clearance is a Rails engine tested against Rails >= 3.2 and Ruby >= 1.9.3.

You can add it to your Gemfile with:

gem "clearance"

Run the bundle command to install it.

After you install Clearance, you need to run the generator:

$ rails generate clearance:install

The Clearance install generator:

Inserts Clearance::User into your User model
Inserts Clearance::Controller into your ApplicationController
Creates an initializer file to allow further configuration.
Creates a migration file that either create a users table or adds any necessary columns to the existing table.

Configure

Override any of these defaults in config/initializers/clearance.rb:

Clearance.configure do |config|
  config.allow_sign_up = true
  config.cookie_domain = ".example.com"
  config.cookie_expiration = lambda { |cookies| 1.year.from_now.utc }
  config.cookie_name = "remember_token"
  config.cookie_path = "/"
  config.routes = true
  config.httponly = false
  config.mailer_sender = "reply@example.com"
  config.password_strategy = Clearance::PasswordStrategies::BCrypt
  config.redirect_url = "/"
  config.rotate_csrf_on_sign_in = false
  config.secure_cookie = false
  config.sign_in_guards = []
  config.user_model = User
end

The install generator will set rotate_csrf_on_sign_in to true, so new installations will get this behavior from the start. This helps avoid session fixation attacks, and will become the default in Clearance 2.0.

Use

Access Control

Use the require_login filter to control access to controller actions.

class ArticlesController < ApplicationController
  before_action :require_login

  def index
    current_user.articles
  end
end

Clearance also provides routing constraints that can be used to control access at the routing layer:

Blog::Application.routes.draw do
  constraints Clearance::Constraints::SignedIn.new { |user| user.admin? } do
    root to: "admin/dashboards#show", as: :admin_root
  end

  constraints Clearance::Constraints::SignedIn.new do
    root to: "dashboards#show", as: :signed_in_root
  end

  constraints Clearance::Constraints::SignedOut.new do
    root to: "marketing#index"
  end
end

Helper Methods

Use current_user, signed_in?, and signed_out? in controllers, views, and helpers. For example:

<% if signed_in? %>
  <%= current_user.email %>
  <%= button_to "Sign out", sign_out_path, method: :delete %>
<% else %>
  <%= link_to "Sign in", sign_in_path %>
<% end %>

Password Resets

When a user resets their password, Clearance delivers them an email. You should change the mailer_sender default, used in the email's "from" header:

Clearance.configure do |config|
  config.mailer_sender = "reply@example.com"
end

Integrating with Rack Applications

Clearance adds its session to the Rack environment hash so middleware and other Rack applications can interact with it:

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 Clearance

Routes

See config/routes.rb for the default set of routes.

As of Clearance 1.5 it is recommended that you disable Clearance routes and take full control over routing and URL design. This ensures that your app's URL design won't be affected if the gem's routes and URL design are changed.

To disable the routes, set config.routes = false. You can optionally run rails generate clearance:routes to dump a copy of the default routes into your application for modification.

Controllers

See app/controllers/clearance for the default behavior. Many protected methods were extracted in these controllers in an attempt to make overrides and hooks simpler.

To override a Clearance controller, subclass it and update the routes to point to your new controller (see the "Routes" section).

class PasswordsController < Clearance::PasswordsController
class SessionsController < Clearance::SessionsController
class UsersController < Clearance::UsersController

Redirects

All of these controller methods redirect to Clearance.configuration.redirect_url (which is / by default):

passwords#url_after_update
sessions#url_after_create
sessions#url_for_signed_in_users
users#url_after_create
application#url_after_denied_access_when_signed_in

To override them all at once, change the global configuration of redirect_url. To change individual URLs, override the appropriate method.

application#url_after_denied_access_when_signed_out defaults to sign_in_url. Override this method to change this.

Views

See app/views for the default behavior.

To override a view, create your own copy of it:

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

You can use the Clearance views generator to copy the default views to your application for modification.

$ rails generate clearance:views

Layouts

By default, Clearance uses your application's default layout. If you would like to change the layout that Clearance uses when rendering its views, simply specify the layout in an initializer.

Clearance::PasswordsController.layout "my_passwords_layout"
Clearance::SessionsController.layout "my_sessions_layout"
Clearance::UsersController.layout "my_admin_layout"

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 for the default behavior.

You can also install clearance-i18n for access to additional, user-contributed translations.

User Model

See lib/clearance/user.rb for the default behavior. You can override those methods as needed.

Deliver Email in Background Job

Clearance has a password reset mailer. If you are using Rails 4.2 and Clearance 1.6 or greater, Clearance will use ActiveJob's deliver_later method to automatically take advantage of your configured queue.

If you are using an earlier version of Rails, you can override the Clearance::Passwords controller and define the behavior you need in the deliver_email method.

class PasswordsController < Clearance::PasswordsController
  def deliver_email(user)
    ClearanceMailer.delay.change_password(user)
  end
end

Extending Sign In

By default, Clearance will sign in any user with valid credentials. If you need to support additional checks during the sign in process then you can use the SignInGuard stack. For example, using the SignInGuard stack, you could prevent suspended users from signing in, or require that users confirm their email address before accessing the site.

SignInGuards 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 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:

Clearance.configure do |config|
  config.sign_in_guards = [EmailConfirmationGuard]
end

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

Testing

Fast Feature Specs

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.

Enable the Middleware in Test:

# config/environments/test.rb
MyRailsApp::Application.configure do
  # ...
  config.middleware.use Clearance::BackDoor
  # ...
end

Usage:

visit root_path(as: user)

Additionally, if User#to_param is overridden, you can pass a block in order to override the default behavior:

# config/environments/test.rb
MyRailsApp::Application.configure do
  # ...
  config.middleware.use Clearance::BackDoor do |username|
    Clearance.configuration.user_model.find_by(username: username)
  end
  # ...
end

Ready Made Feature Specs

If you're using RSpec, you can generate feature specs to help prevent regressions in Clearance's integration with your Rails app over time. These feature specs, will also require factory_girl_rails.

To Generate the clearance specs, run:

$ rails generate clearance:specs

Controller Test Helpers

To test controller actions that are protected by before_action :require_login, require Clearance's test helpers in your test suite.

For rspec, add the following line to your spec/rails_helper.rb or spec/spec_helper if rails_helper does not exist:

require "clearance/rspec"

For test-unit, add this line to your test/test_helper.rb:

require "clearance/test_unit"

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

View and Helper Spec Helpers

Does the view or helper you're testing reference signed_in?, signed_out? or current_user? If you require 'clearance/rspec', you will have the following helpers available in your view specs:

sign_in
sign_in_as(user)

These will make the clearance view helpers work as expected by signing in either a new instance of your user model (sign_in) or the object you pass to sign_in_as. If you do not call one of these sign in helpers or otherwise set current_user in your view specs, your view will behave as if there is no current user: signed_in? will be false and signed_out? will be true.

Contributing

Please see CONTRIBUTING.md. Thank you, contributors!

License

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jvanbaarsen/clearance