[!NOTE] Archived Project: Modella is a historical minimalist model framework for Node.js and browser applications. For modern projects, tools like Zod or Prisma are standard.
Modella is a bare-bones data modeling library designed to be extended via plugins.
Model Definition
const Modella = require('modella');
const validators = require('modella-validators');
const User = Modella('User')
.attr('id')
.attr('name')
.attr('email', { required: true })
.use(validators);
// Custom validation rule
User.validate((user) => {
if (!user.name()) {
user.error('name', 'Name is required');
}
});
Model Instances & Properties
// Instantiation
const user = new User({ name: 'Alice', email: '[email protected]' });
// Getters and Setters
user.name(); // -> "Alice"
user.name('Bob'); // Sets name to "Bob"
user.set({ name: 'Charlie' });
// State predicates
user.has('name'); // -> true
user.isNew(); // -> true (not yet saved)
user.isValid(); // Runs sync validators -> true/false
Lifecycle Events
// Persistence events
user.on('save', () => console.log('Saved'));
user.on('create', () => console.log('Created'));
user.on('remove', () => console.log('Removed'));
// Async hooks
user.on('saving', (instance, done) => {
// Pre-save asynchronous hook
done();
});
// Attribute change events
user.on('change', () => console.log('Attributes modified'));
user.on('change email', () => console.log('Email changed'));
Plugin Architecture
A Modella plugin is a higher-order function that decorates the model:
const TimestampsPlugin = () => {
return (Model) => {
Model
.attr('createdAt')
.attr('updatedAt');
Model.on('saving', (record, done) => {
const now = new Date();
if (record.isNew()) record.createdAt(now);
record.updatedAt(now);
done();
});
return Model;
};
};
User.use(TimestampsPlugin());