The principal

The principal is whoever is calling, once Jadpo has checked them: either a user (a person) or a service (another system, such as a partner's server). You declare it once in app.jadpo, with no name. It says which stored record each kind of caller is, and when that record may still sign in:

// app.jadpoprincipal {    user: {        subject: User.authentication_subject        active: User.status == UserStatus.active    }    service: {        subject: Service.name        active: Service.status == ServiceStatus.active    }}

subject:

Jadpo needs to know which record a signed-in caller is. subject: names the field it finds them by, such as User.authentication_subject or User.email. The field must be unique. When your app has tenants (many organisations sharing one app, see Tenancy), it must be a field every tenant shares, so one person is one record. Jadpo looks the caller up by this field whenever it needs their current record.

active:

active: is a condition on the same entity, written with its fields as a query's where: is. A caller whose record doesn't meet it is refused with user_disabled or service_disabled (see Failures). Leave it out and every record counts as active.

What code reads from the caller

The principal has three fields of its own, and no others:

• id: the record's id, a User.id or a Service.id;
• subject: the value of the subject: field;
• strength: how the caller proved who they are, primary or multi_factor.

A role, a tenant or an email address isn't on the principal. Code that needs one reads it from the entity, which is where Policy reads it too.

Users only

service: is optional. Most apps only have users, and leave it out. An app needs at least one of user: and service:.