@active-record-ts/active-model

Typed attributes, dirty tracking, validations, and callbacks for plain TypeScript classes — no database. A port of Rails' ActiveModel.

Used by @active-record-ts/active-record for persistence; usable on its own for form objects, API payloads, etc.

Usage

import { Model } from '@active-record-ts/active-model';

class Signup extends Model {
  declare email: string;
  declare age: number;
}

Signup.attribute('email', 'string');
Signup.attribute('age', 'integer');
Signup.validates('email', { presence: true, format: { with: /@/ } });
Signup.validates('age', { numericality: { greaterThanOrEqualTo: 13 } });

const s = new Signup({ email: '[email protected]', age: 12 });
await s.validate();          // false
s.errors.fullMessages;       // ["Age must be greater than or equal to 13"]

Features

• Typed attributes — attribute(name, type). Built-ins: string, integer, bigint, float, decimal, boolean, date, datetime, binary, json. Register your own with registerType.
• Dirty tracking — record.changed(), record.changes(), record.wasChanged(attr), record.savedChanges().
• Validations — presence, absence, format, length, numericality, inclusion, exclusion, acceptance, confirmation.
• Callbacks — beforeValidation, afterValidation, beforeSave, afterSave, aroundSave. Throw HaltError (or call throwAbort()) inside a before* callback to halt the chain.
• Errors — record.errors exposes Rails-style add, on, fullMessages, etc.
• Inflector — camelize, underscore, pluralize, tableize.

Test

bun run test:active-model