project-work/worker-toolkit-stocks-in-the-future/repo/docs/map/objects/identity/teacher.md

type, cluster, universe, status, entity

type	cluster	universe	status	entity
object	identity	live	verified	app/models/teacher.rb

Teacher

A User with type: "Teacher" — runs classrooms and gradebooks. Owns no portfolio and cannot trade.

Verified 2026-08-16 against commit 63732df.

Why this shape

Login is by username app-wide, but teachers think in email addresses. Rather than splitting the auth key, Teacher copies email into username on every validation (app/models/teacher.rb:9,17-19). So a teacher's username is their email, kept in sync automatically — change the email and the login changes with it. This is the exact inverse of student, whose username is assigned and whose email is usually nil.

attr_accessor :school_id (:4) is a form-only field. It is not a column and not persisted — a teacher reaches a school only through classrooms.

Shape

• STI subclass of user; no table of its own
• has_many :teacher_classrooms, has_many :classrooms, through: (:6-7)
• before_validation :sync_username_from_email (:9)
• display_name prefers name, then the email local-part (:11-13)
• Join table teacher_classrooms — unique on [teacher_id, classroom_id] (db/schema.rb:368). No behaviour of its own, so it has no card.

Connected to

• owns: classroom (through teacher_classrooms)
• owned-by: —
• joins: teacher_classrooms
• looks-like-but-is-not: a teacher is not an admin. Admin is a boolean on users; teacher_or_admin? (app/models/user.rb:53-55) exists precisely because the two are independent and often both true.

If you change this

• Hits: sign-in for every teacher if you touch sync_username_from_email — it rewrites username, the auth key; Order.for_teacher (app/models/order.rb:40-42), which scopes orders through users.classroom_id, not through teacher_classrooms; Admin::Teachers::DeactivationsController / ReactivationsController.
• Does not hit: portfolio. Portfolio validates that its user is a student (app/models/portfolio.rb:102-104), so no teacher change can create or affect one.

Surfaces

Surface	Role
Admin::TeachersController	admin CRUD
Admin::Teachers::DeactivationsController / ReactivationsController	discard / restore
ClassroomsController, GradeBooksController	authorizes as teacher

See

• Source: app/models/teacher.rb
• Base class: user