@nozbe/watermelondb/src/decorators/immutableRelation/index.js

Build powerful React Native and React web apps that scale from hundreds to tens of thousands of records and remain fast

// @flow

import { type Decorator } from '../../utils/common/makeDecorator'
import type { ColumnName, TableName } from '../../Schema'

import relation from '../relation'

// Defines a model property that fetches a record with a specific ID
// The property defined must be *immutable*, i.e. the relation ID must never change
// Returns an immutable Relation object. See watermelondb/Relation for more information
//
// If the property *can* change, use `relation` instead
//
// You can only assign a value inside a `collection.create()` or `collection.prepareCreate()` block
//
// relationIdColumn - name of the column with record ID
// relationTable - name of the table containing desired recods
//
// Example: a Comment has an author (and an author can never change), so it may define:
//   @immutableRelation('team_member', 'author_id') author: Relation<TeamMember>

const immutableRelation: Decorator = (
  relationTable: TableName<any>,
  relationIdColumn: ColumnName,
) => relation(relationTable, relationIdColumn, { isImmutable: true })

export default immutableRelation