createToken() protected method Creates token from its

$clientId public property OAuth client ID.

$clientSecret public property OAuth client secret.

fetchAccessToken() public method Fetches access token

composeRequestCurlOptions() protected method Composes

apiInternal() protected method Performs request to the

defaultReturnUrl() protected method Composes default

$tokenUrl public property Token request URL endpoint.

$version public property Protocol version.

buildAuthUrl() public method Composes user authorization