Add a @readonly attribute #524
Description
This attribute would mark a field as readonly, generating a schema that omits the field from create/update/upsert mutation types, but remains present elsewhere. This is useful in restricting fields to their default values.
It could optionally accept a parameter that allows the field to be present in the input, but only during creation. This is useful for allowing relations to be initialized, but not changed at a later time.
The presence of a readonly field in an input where the policy does not allow for it would throw a rejected by policy error.
Note that there is already some overlap in the current @@deny attribute and zenstackhq/zenstack#671, but this feature would be much more ergonomic for the most common use cases. It improves the readability of zmodel files, and surfaces the restriction to clients at build-time rather than runtime.
Sample Usage
model User {
id String @id @default(uuid()) @readonly
name String
createdAt DateTime @default(now()) @readonly
updatedAt DateTime @updatedAt @readonly
posts Post[]
}
model Post {
id String @id @default(uuid()) @readonly
title String
userId String @readonly(creatable: true)
user User @relation(fields: [userId], references: [id])
createdAt DateTime @default(now()) @readonly
updatedAt DateTime @updatedAt @readonly
}