Time zones

index.js

'use strict';

const { faker } = require('@faker-js/faker');
const { DateTime, Settings } = require('luxon');

Settings.defaultZone = "utc";
console.info(`defaultZone zoneName ${DateTime.local().zoneName}`);

const dt = DateTime.local();

class Client {
  constructor(zone = '') {
    this.id = faker.string.uuid();
    this.firstName = faker.person.firstName();
    this.timezone = zone || faker.location.timeZone();
  }

  getZone() {
    return this.timezone;
  }

  getId() {
    return this.id;
  }

  getFirstName() {
    return this.firstName;
  }

  getNow() {
    return DateTime.now().setZone(this.timezone).toISO();
  }
}

class Store {
  constructor(zone = '') {
    this.products = [];
    this.timezone = zone || faker.location.timeZone();
  }

  getZone() {
    return this.timezone;
  }

  getProducts() {
    for (const product of this.products) {
      const { id, title, createdAt, updatedAt } = product;
      console.info(`${id}
      ${title}
      created ${DateTime.fromMillis(createdAt).toISO()}
      updatedAt ${DateTime.fromMillis(updatedAt).toISO()}
      `);
    }
  }

  loadProducts(len = 10) {
    this.products = Array.from({ length: len }, (v, i) => ({
      id: faker.string.uuid(),
      title: faker.word.words({ count: 5, min: 1, max: 5 }),
      createdAt: DateTime.fromJSDate(faker.date.past()).setZone(this.timezone).toMillis(),
      updatedAt: DateTime.fromJSDate(faker.date.past()).setZone(this.timezone).toMillis(),
    }));
  }
}

const start = async () => {
  try {
    console.group('CLIENTS');
    const clientA = new Client();
    const clientB = new Client();

    console.info(`clientA ${clientA.getId()}
    zone: ${clientA.getZone()} 
    now ${clientA.getNow()}`);

    console.info(`clientB ${clientB.getId()}
    zone: ${clientB.getZone()} 
    now: ${clientB.getNow()}`);

    console.groupEnd('CLIENTS');

    console.group('PRODUCTS');

    const store = new Store('utc');
    store.loadProducts(20);
    store.getProducts();

    console.groupEnd('PRODUCTS');


    console.group('SERVER TIME');
    // console.dir(dt, { depth: 3 });
    console.info(`iso ${dt.toISO()}`);
    console.info(`offset ${dt.offset}`);
    console.info(`timestamp ${dt.toMillis()}`);
    console.info(`zone ${dt.zoneName}`);
    console.groupEnd('SERVER TIME');


    Settings.defaultZone = "system";
    console.info(`defaultZone zoneName ${DateTime.local().zoneName}`);
  } catch (exc) {
    console.error(' Error ', exc.message);
  }
};

start();