OmniAuth Identity
The OmniAuth Identity gem provides a way for applications to utilize a traditional login/password based authentication system without the need to give up the simple authentication flow provided by OmniAuth. Identity is designed on purpose to be as featureless as possible: it provides the basic construct for user management and then gets out of the way.
Usage
This can be a bit hard to understand the first time. Luckily, Ryan Bates made a Railscast about it!
You use omniauth-identity
just like you would any other OmniAuth provider: as a
Rack middleware. The basic setup for a email/password authentication would
look something like this:
use OmniAuth::Builder do
provider :identity, :fields => [:email]
end
Next, you need to create a model (called Identity by default
) that will be
able to persist the information provided by the user. Luckily for you, there
are pre-built models for popular ORMs that make this dead simple.
Note: OmniAuth Identity is different from many other user authentication
systems in that it is not built to store authentication information in your primary
User
model. Instead, the Identity
model should be associated with your
User
model giving you maximum flexibility to include other authentication
strategies such as Facebook, Twitter, etc.
ActiveRecord
Just subclass OmniAuth::Identity::Models::ActiveRecord
and provide fields
in the database for all of the fields you are using.
class Identity < OmniAuth::Identity::Models::ActiveRecord
# Add whatever you like!
end
Mongoid
Include the OmniAuth::Identity::Models::Mongoid
mixin and specify
fields that you will need.
class Identity
include Mongoid::Document
include OmniAuth::Identity::Models::Mongoid
field :email, type: String
field :name, type: String
field :password_digest, type: String
end
MongoMapper
Include the OmniAuth::Identity::Models::MongoMapper
mixin and specify
fields that you will need.
class Identity
include MongoMapper::Document
include OmniAuth::Identity::Models::MongoMapper
key :email, String
key :name, String
key :password_digest, String
end
DataMapper
Include the OmniAuth::Identity::Models::DataMapper
mixin and specify
fields that you will need.
class Identity
include DataMapper::Resource
include OmniAuth::Identity::Models::DataMapper
property :id, Serial
property :email, String
property :password_digest, Text
attr_accessor :password_confirmation
end
CouchPotato
Include the OmniAuth::Identity::Models::CouchPotatoModule
mixin and specify fields that you will need.
class Identity
include CouchPotato::Persistence
include OmniAuth::Identity::Models::CouchPotatoModule
property :email
property :password_digest
def self.where search_hash
CouchPotato.database.view Identity.by_email(:key => search_hash)
end
view :by_email, :key => :email
end
Once you've got an Identity persistence model and the strategy up and
running, you can point users to /auth/identity
and it will request
that they log in or give them the opportunity to sign up for an account.
Once they have authenticated with their identity, OmniAuth will call
through to /auth/identity/callback
with the same kinds of information
it would had the user authenticated through an external provider.
Simple!
Custom Auth Model
To use a class other than the default, specify the :model option to a different class.
use OmniAuth::Builder do
provider :identity, :fields => [:email], :model => MyCustomClass
end
Customizing Registration Failure
To use your own custom registration form, create a form that POSTs to '/auth/identity/register' with 'password', 'password_confirmation', and your other fields.
<%= form_tag '/auth/identity/register' do |f| %>
<h1>Create an Account</h1>
<%= text_field_tag :email %>
<%= password_field_tag :password %>
<%= password_field_tag :password_confirmation %>
<%= submit_tag %>
<% end %>
Beware not to nest your form parameters within a namespace. This strategy looks for the form parameters at the top level of the post params. If you are using simple_form, then you can avoid the params nesting by specifying :input_html.
<%= simple_form_for @identity, :url => '/auth/identity/register' do |f| %>
<h1>Create an Account</h1>
<%# specify :input_html to avoid params nesting %>
<%= f.input :email, :input_html => {:name => 'email'} %>
<%= f.input :password, :as => 'password', :input_html => {:name => 'password'} %>
<%= f.input :password_confirmation, :label => "Confirm Password", :as => 'password', :input_html => {:name => 'password_confirmation'} %>
<button type='submit'>Sign Up</button>
<% end %>
Next you'll need to let OmniAuth know what action to call when a registration fails. In your OmniAuth configuration, specify any valid rack endpoint in the :on_failed_registration option.
use OmniAuth::Builder do
provider :identity,
:fields => [:email],
:on_failed_registration => UsersController.action(:new)
end
For more information on rack endpoints, check out this introduction and ActionController::Metal
Customizing Locate Conditions
You can customize the way that matching records are found when authenticating. For example, for a site with multiple domains, you may wish to scope the search within a particular subdomain. To do so, add :locate_conditions to your config. The default value is:
:locate_conditions => lambda { |req| { model.auth_key => req['auth_key']} }
locate_conditions takes a Proc object, and must return a hash. The resulting hash is used
as a parameter in the locate method for your ORM. The proc is evaluated in the
callback context, and has access to the Identity model (using model
) and receives the request
object as a parameter. Note that model.auth_key defaults to 'email', but is also configurable.
Note: Be careful when customizing locate_conditions. The best way to modify the conditions is to copy the default value, and then add to the hash. Removing the default condition will almost always break things!
License
MIT License. See LICENSE for details.
Copyright
Copyright (c) 2010-2015 Michael Bleigh, and Intridea, Inc.