Class Entity

packages/repository/src/model.ts:440–512

 * Base class for entities which have unique ids
 */
export class Entity extends Model implements Persistable {
  /**
   * Get the names of identity properties (primary keys).
   */
  static getIdProperties(): string[] {
    return this.definition.idProperties();
  }

  /**
   * Get the identity value for a given entity instance or entity data object.
   *
   * @param entityOrData - The data object for which to determine the identity
   * value.
   */
  static getIdOf(entityOrData: AnyObject): any {
    if (typeof entityOrData.getId === 'function') {
      return entityOrData.getId();
    }

    const idName = this.getIdProperties()[0];
    return entityOrData[idName];
  }

  /**
   * Get the identity value. If the identity is a composite key, returns
   * an object.
   */
  getId(): any {
    const definition = (this.constructor as typeof Entity).definition;
    const idProps = definition.idProperties();
    if (idProps.length === 1) {
      return (this as AnyObject)[idProps[0]];
    }
    if (!idProps.length) {
      throw new Error(
        `Invalid Entity ${this.constructor.name}:` +
          'missing primary key (id) property',
      );
    }
    return this.getIdObject();
  }

  /**
   * Get the identity as an object, such as `{id: 1}` or
   * `{schoolId: 1, studentId: 2}`
   */
  getIdObject(): Object {
    const definition = (this.constructor as typeof Entity).definition;
    const idProps = definition.idProperties();
    const idObj = {} as any;
    for (const idProp of idProps) {
      idObj[idProp] = (this as AnyObject)[idProp];
    }
    return idObj;
  }

  /**
   * Build the where object for the given id