Model.updateAttributes

1-updateattributes.js

var loopback = require('loopback');
var app = loopback();

var Car = loopback.createModel('Car');

Car.observe('before save', function(ctx) {
  console.log('before save %j', ctx);
  return Promise.resolve();
});

//app.dataSource('db', { connector: 'memory' });
app.dataSource('db', { connector: 'mongodb' });
app.model(Car, { dataSource: 'db' });

var id, c1, c2;
Car.create({ color: 'red', age: 1 })
  .then(function(car) {
    id = car.id;
  })
  .then(function() {
    return Car.findById(id).then(function(car) { c1 = car; });
  })
  .then(function() {
    return Car.findById(id).then(function(car) { c2 = car; });
  })
  .then(function() {
    // Simulate two "PUT /car/:id" requests running in parallel
    return Promise.all([
      c1.updateAttributes({ color: 'white' }),
      c2.updateAttributes({ age: 2 })
    ]);
  })
  .then(function() {
    return Car.findById(id).then(function(car) {
      console.log('RESULT', car);
      process.exit();
    });
  });

2-memory

before save {"instance":{"color":"red","age":1}}
before save {"where":{"id":1},"data":{"color":"white"}}
before save {"where":{"id":1},"data":{"age":2}}
RESULT { color: 'white', age: 2, id: 1 }

3-mongodb

before save {"instance":{"color":"red","age":1}}
before save {"where":{"id":"54f81156ac57108d1ee37985"},"data":{"color":"white"}}
before save {"where":{"id":"54f81156ac57108d1ee37985"},"data":{"age":2}}
RESULT { color: 'white', age: 2, id: 54f81156ac57108d1ee37985 }