Class Support

Akita also supports using a class as the underlying value instead of a plain object. In most cases, we don't recommend doing so for the following reasons:

1. We can’t store classes in the database. A typical example of this is when you need to save the store snapshot.
2. Classes are harder to use with web workers, due to serialization concerns.
3. There are various third-party tools (for example immer) that only work with plain objects.

However, sometimes they can be useful. Here's an example that uses a class:

user.model.ts

export class User {
  constructor({ firstName, lastName, token }: Partial<User>) {
    this.firstName = firstName;
    this.lastName = lastName;
    this.token = token;
  }

  get name() {
    return `${this.firstName} ${this.lastName}`;
  }
}

user.store.ts

export interface UserState extends EntityState<User> {}

@StoreConfig({ name: 'user' })
export class UserStore extends EntityStore<UserState> {
  constructor() {
    super();
  }
}

danger

The class constructor should accept only one parameter which is a plain object

In this case, when you call update(), Akita will take care to instantiate a new User by merging the entity's current state with the new parameters.

You can use the akitaPreAddEntity to create a new instance of the entity:

@StoreConfig({ name: 'posts' })
export class PostsStore extends EntityStore<PostsState> {
  constructor() {
    super();
  }

  akitaPreAddEntity(nextState: Post): Post {
    return new Post(nextState);
  }
}