morphMap

Polymorphic-relation type alias registry. Map short type names ('user', 'post') to model classes so the *_type column on a polymorphic table stores the alias instead of a fully-qualified class name.

Signature

class Relation {
  static morphMap(map?: Record<string, typeof Model>, merge?: boolean): Record<string, typeof Model>;
}

Parameters

Name	Required	Description
map	optional	Object of alias → model class. Pass nothing to read the current map.
merge	default true	When true, merges with the existing map. Pass false to replace.

Returns the resolved map (after the call).

Real-World Use Cases

1. Register aliases at app startup (default merge)

import { Relation } from '@gradii/fedaco';
import { User } from './models/user';
import { Post } from './models/post';

const map1 = { user: User };
const map2 = { post: Post };

Relation.morphMap(map1);
Relation.morphMap(map2);
// Both 'user' and 'post' are now registered (default behaviour merges).

2. Replace the map (no merge)

Relation.morphMap({ user: User }, /* merge */ false);
Relation.morphMap({ post: Post }, /* merge */ false);
// After the second call, only 'post' is in the map.

3. Use with morph relations

Once registered, morphMany / morphTo columns store the alias:

Relation.morphMap({
  user: User,
  post: Post,
});

const user = await User.createQuery().create({ email: 'linbolen@gradii.com' });
await user.NewRelation('photos').create({ name: 'Avatar 1' });
await user.NewRelation('photos').create({ name: 'Avatar 2' });

const post = await user.NewRelation('posts').create({ name: 'First Post' });
await post.NewRelation('photos').create({ name: 'Hero 1' });
await post.NewRelation('photos').create({ name: 'Hero 2' });

(await user.photos)[0].GetAttribute('imageable_type'); // 'user'
(await post.photos)[0].GetAttribute('imageable_type'); // 'post'

The imageable_type column stores the alias ('user' / 'post') — not the class name. morphTo resolves back to the right class via the same map:

const photo = await Photo.createQuery().first();
const owner = await photo.imageable; // FedacoTestUser

4. Read current map

const m = Relation.morphMap();
console.log(m); // { user: User, post: Post }

Why Use a Morph Map?

• Refactor-safe: rename your Post class without breaking historical rows.
• Database-friendly: short, stable type names are easier to query and index.
• Cross-language: another service reading the same database can rely on stable type tokens, regardless of whether your code is TS, PHP, or anything else.

Common Pitfalls

• Register before any morph queries run. If a polymorphic query fires before morphMap is called, fedaco will store/expect the bare class name. Mixing the two yields rows that no longer resolve.
• Aliases must be unique. A second call with the same alias overwrites the previous mapping; downstream rows pointing at the older mapping silently break.
• All polymorphic models should be in the map. Don't half-register — either map every model or none, otherwise queries will mix aliases and class names.

See Also

• Polymorphic Relationships.
• Custom Polymorphic Types.