To support the concept of registering for an app, we will need to first create a User model. A user, similar to a Shopping List or an Item model in our Vapor app, will be a class that contains certain properties, such as name, email, and password. When a user tries to register for our app, they will provide us with their name, email, and password, and we will take those and create a new user record if it does not already exist. In our app, we will use email as the ID by which a user can log in along with their password. Some websites or apps may even have a concept of username, which can be added as a property to the User model; however, for our app, email will suffice to serve as a unique identifier by which we can find a user account.
The user will need to provide a password when registering, and using that password, they will be able to log in. We cannot simply store the password in its original text form in the database, as there are a lot of security concerns since...