OAuth stack middleware.

• session: The request must have session handling accounted for. You can do this by prepending the stack/session middleware to this one.

• credentials: You need to have some sort of OAuth server. By default, stack/oauth will use twitter. But you can change that through the oauth_service.class config parameter.

use Igorw\Stack\OAuth;

$app = new OAuth($app, [
    'key'           => 'foo',
    'secret'        => 'bar',
    'callback_url'  => 'http://localhost:8080/auth/verify',
    'success_url'   => '/',
    'failure_url'   => '/auth',
]);

• /auth
• /auth/verify

• config validation
• tests
• more flexible path config (?)