OmniContacts

Inspired by the popular OmniAuth, OmniContacts is a library that enables users of an application to import contacts from their email or Facebook accounts. The email providers currently supported are Gmail, Yahoo and Hotmail.
OmniContacts is a Rack middleware, therefore you can use it with Rails, Sinatra and any other Rack-based framework.

OmniContacts uses the OAuth protocol to communicate with the contacts provider. Yahoo still uses OAuth 1.0, while Facebook, Gmail and Hotmail support OAuth 2.0.
In order to use OmniContacts, it is therefore necessary to first register your application with the provider and to obtain client_id and client_secret.

Usage

Add OmniContacts as a dependency:

gem "omnicontacts"

As for OmniAuth, there is a Builder facilitating the usage of multiple contacts importers. In the case of a Rails application, the following code could be placed at config/initializers/omnicontacts.rb:

require "omnicontacts"

Rails.application.middleware.use OmniContacts::Builder do
  importer :gmail, "client_id", "client_secret", {:redirect_path => "/oauth2callback", :ssl_ca_file => "/etc/ssl/certs/curl-ca-bundle.crt"}
  importer :yahoo, "consumer_id", "consumer_secret", {:callback_path => '/callback'}
  importer :hotmail, "client_id", "client_secret"
  importer :facebook, "client_id", "client_secret"
end

Every importer expects client_id and client_secret as mandatory, while :redirect_path and :ssl_ca_file are optional.
Since Yahoo implements the version 1.0 of the OAuth protocol, naming is slightly different. Instead of :redirect_path you should use :callback_path as key in the hash providing the optional parameters.
While :ssl_ca_file is optional, it is highly recommended to set it on production environments for obvious security reasons. On the other hand it makes things much easier to leave the default value for :redirect_path and :callback path, the reason of which will be clear after reading the following section.

Register your application

• For Gmail : Google API Console

• For Yahoo : Yahoo Developer Network

• For Hotmail : Microsoft Developer Network

• For Facebook : Facebook Developers

Note:

Please go through MSDN if above Hotmail link will not work.

Integrating with your Application

To use the Gem you first need to redirect your users to /contacts/:importer, where :importer can be facebook, gmail, yahoo or hotmail. No changes to config/routes.rb are needed for this step since OmniContacts will be listening on that path and redirect the user to the email provider's website in order to authorize your app to access his contact list. Once that is done the user will be redirected back to your application, to the path specified in :redirect_path (or :callback_path for yahoo). If nothing is specified the default value is /contacts/:importer/callback (e.g. /contacts/yahoo/callback). This makes things simpler and you can just add the following line to config/routes.rb:

  match "/contacts/:importer/callback" => "your_controller#callback"

The list of contacts can be accessed via the omnicontacts.contacts key in the environment hash and it consists of a simple array of hashes.
The following table shows which fields are supported by which provider:

Provider	:email	:id	:profile_picture	:name	:first_name	:last_name	:address_1	:address_2	:city	:region	:postcode	:country	:phone_number	:birthday	:gender	:relation
Gmail	X	X		X	X	X	X	X	X	X	X	X	X	X	X	X
Facebook		X	X	X	X	X								X	X	X
Yahoo	X	X		X	X	X	X	X	X	X	X			X
Hotmail	X	X	X	X	X	X								X	X

Obviously it may happen that some fields are blank even if supported by the provider in the case that the contact did not provide any information about them.

The information for the logged in user can also be accessed via 'omnicontacts.user' key in the environment hash. It consists of a simple hash which includes the same fields as above.

The following snippet shows how to simply print name and email of each contact, and also the the name of logged in user:

def contacts_callback
  @contacts = request.env['omnicontacts.contacts']
  @user = request.env['omnicontacts.user']
  puts "List of contacts of #{user[:name]} obtained from #{params[:importer]}:"
  @contacts.each do |contact|
    puts "Contact found: name => #{contact[:name]}, email => #{contact[:email]}"
  end
end

If the user does not authorize your application to access his/her contacts list, or any other inconvenience occurs, he/she is redirected to /contacts/failure. The query string will contain a parameter named error_message which specifies why the list of contacts could not be retrieved. error_message can have one of the following values: not_authorized, timeout and internal_error.

Tips and tricks

OmniContacts supports OAuth 1.0 and OAuth 2.0 token refresh, but for both it needs to persist data between requests. OmniContacts stores access tokens in the session. If you hit the 4KB cookie storage limit you better opt for the Memcache or the Active Record storage.

Gmail requires you to register the redirect_path on their website along with your application. Make sure to use the same value present in the configuration file, or /contacts/gmail/callback if using the default.

To configure the max number of contacts to download from Gmail, just add a max results parameter in your initializer:

importer :gmail, "xxx", "yyy", :max_results => 1000

Yahoo requires you to configure the Permissions your application requires. Make sure to go the Yahoo website and to select Read permission for Contacts.

Hotmail presents a "peculiar" feature. Their API returns a Contact object which does not contain an e-mail field! However, if the contact has either name, family name or both set to null, than there is a field called name which does contain the e-mail address. This means that it may happen that an Hotmail contact does not contain the email field.

Integration Testing

You can enable test mode like this:

  OmniContacts.integration_test.enabled = true

In this way all requests to /omnicontacts/provider will be redirected automatically to /omnicontacts/provider/callback.

The mock method allows to configure per-provider the result to return:

  OmniContacts.integration_test.mock(:provider_name, :email => "[email protected]")

You can either pass a single hash or an array of hashes. If you pass a string, an error will be triggered with subsequent redirect to /contacts/failure?error_message=internal_error

Follows a full example of an integration test:

  OmniContacts.integration_test.enabled = true
  OmniContacts.integration_test.mock(:gmail, :email => "[email protected]")
  visit '/contacts/gmail'
  page.should have_content("[email protected]")

Working on localhost

Since Hotmail and Facebook do not allow the usage of localhost as redirect path for the authorization step, a workaround is to use the localtunnel gem.
This gem is really useful when you need someone, the contacts provider in this case, to access your locally running application using a unique url.

Install the Gem using RubyGems:

sudo gem install localtunnel

Start localtunnel passing your public SSH key and the port where your application is running:

localtunnel -k ~/.ssh/id_rsa.pub 3000

Check the output to see something like

Port 3000 is now publicly accessible from http://8bv2.localtunnel.com ...

The printed Url is the one you can now use to access your application.

Example application

Thanks to @sonianand11, you can find a full example of a Rails application using OmniContacts at: https://github.com/sonianand11/omnicontacts_example

Thanks

As already mentioned above, a special thanks goes to @sonianand11 for implementing an example app.
Thanks also to @asmatameem for her huge contribution. She indeed added support for Facebook and for many fields which were missing before.

License

Copyright (c) 2012-2013 Diego81

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.