Get union type of type field (@@delegate) from table with Polymorphic Relations

[piscopancer]

I wonder how I can conveniently extract and use this union type in my app

I thought I can get it like so

import { type Notification } from '@prisma/client'

type NotificationType = Notification['type']

but it's not the case because type of Notification is string representing its table value, which is correct, but not the union type I needed

Schema for my Notification is below

model Notification {
  id         Int      @id @default(autoincrement())
  createdAt  DateTime @default(now())
  type       String
  senderId   Int
  sender     User     @relation("user-notification-sent", fields: [senderId], references: [id], onDelete: Cascade)
  receiverId Int
  receiver   User     @relation("user-notification-received", fields: [receiverId], references: [id], onDelete: Cascade)

  @@delegate (type)
}

model AddedToGroupNotification extends Notification {
  groupId Int
  group   Group @relation(fields: [groupId], references: [id], onDelete: Cascade)
}

model AddedToCourseNotification  extends Notification {
  courseId Int
  course   Course @relation(fields: [courseId], references: [id], onDelete: Cascade)
}

What I want in the end is

type NotificationType = 'AddedToGroupNotification' | 'AddedToCourseNotification' // not written by hand xd

[jiashengguo]

@piscopancer, firslty sorry for the late response, we didn't check the discussion that often. What you want should be achieved by this:

import type { Notification } from "@zenstackhq/runtime/prisma";

type NotificationType = Notification['type']

There is a post for a complete example of Polymorphic with more details:

https://zenstack.dev/blog/ocp