Attempts to log in the user. The user can choose between multiple login strategies. A strategy can be ‘basic’ or ‘facebook’ login. After login, the user storage becomes available to store data in a shop-global scope and can be shared across devices. Based on the shop, custom errors can be returned to react to in the theme. Calling this pipeline when a user is logged in results in an error because that usually means there some kind of issue in the theme.
Login. They differ depending on the strategy.
Returns an empty object.