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@AlexAegis
Created October 23, 2020 14:50
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Convert relative models to foreign keys
export interface Model {
id: number;
}
export interface FooModel extends Model {
name: string;
}
export interface BarModel extends Model {
name: string;
foo: FooModel;
foos: FooModel[];
}
export type UnsavedModel<T extends Model> = Omit<T, 'id'> & { id?: number };
export const isSaved = <T extends Model>(t: UnsavedModel<T>): t is T => typeof t.id === 'number';
export type ConvertModelPropertiesTo<T extends Model, P, K extends keyof T = keyof T> = {
[p in K]: T[p] extends Model[] ? P[] : T[p] extends Model ? P : T[p];
};
/**
* Converts every or the selected Model like objects to a `number`
* or `number[]` to represent unresolved relative Models
*/
export type FlatModel<T extends Model, K extends keyof T = keyof T> =
| ConvertModelPropertiesTo<T, number, K>
| Omit<T, K>;
const bar: BarModel = { foo: { id: 1, name: '' }, id: 1, name: '', foos: [] };
const bar2: FlatModel<BarModel, 'foo'> = { foo: 1, foos: [], id: 2, name: '' };
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