OAuthとは

OAuthは認可情報の委譲のための仕様
-あらかじめ信頼関係を構築したサービス間で、ユーザの同意のもとに、セキュアにユーザの権限を受け渡しする
※自分が利用したいサービスに最低限必要な権限のみを委譲することができる。そのため、basic認証と比べて柔軟かつセキュアな運用が可能

認可情報の委譲を行う仕様には、Google、Yahoo!、Flickr、Facebookなどが独自に提供しているものが

OAuth Service Provider(Google, Yahoo, Twitter)
OAuth Consumer
Users

[vagrant@localhost api]$ php composer.phar
   ______
  / ____/___  ____ ___  ____  ____  ________  _____
 / /   / __ \/ __ `__ \/ __ \/ __ \/ ___/ _ \/ ___/
/ /___/ /_/ / / / / / / /_/ / /_/ (__  )  __/ /
\____/\____/_/ /_/ /_/ .___/\____/____/\___/_/
                    /_/
Composer version 1.6.2 2018-01-05 15:28:41

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