Changing a shopify order's location based on the shipping address of the order using order.created/order.updated webhooks

webhook.js

// For posterity, I'm saving/sharing some code I wrote for a shopify app I ran
// in which I had two physical warehouses: one in Maryland, and one in California.
// Each of these was its own "Location" in Shopify, and I wanted every order
// to be automatically assigned to one or the other based on the shipping address.
// I ran this webhook on Autocode: https://autocode.com/
// which makes it really easy to stand up a webhook without futzing with servers.

const Shopify = require('shopify-api-node');

const shopify = new Shopify({
  shopName: 'my-shop-name',
  apiKey: process.env.SHOPIFY_API_KEY,
  password: process.env.SHOPIFY_API_PW,
});

const californiaLocationId = 'XYZ123';
const marylandLocationId = 'XYZ456';

const westCoastStates = new Set([
  // Based on https://www.ups.com/using/services/servicemaps/maps25/map_0774_FEB21.gif
  // and (from MD): https://www.ups.com/using/services/servicemaps/maps25/map_0140_FEB21.gif
  
  // 1-2 day
  'CA',
  'NV',
  
  // 2 days
  'WA',
  'OR',
  'AZ',
  'UT',
  'HI',
  
  // 2-3 days
  'ID',
  'WY',
  
  // 3 days
  'AK',
  'NM',
  //'CO', keep on MD for now.
  
  // 3-4 days
  'MT',
]);


module.exports = async (context) => {
  const {
    id,
    order_number,
    created_at,
    updated_at,
    shipping_address,
    fulfillment_status,
    line_items,
  } = context.params;
  
  console.log({
    id,
    order_number,
    created_at,
    updated_at,
    shipping_address,
    fulfillment_status,
    tags,
  });
  
  
  if (
    shipping_address.country_code === 'US' &&
    westCoastStates.has(shipping_address.province_code) &&
    fulfillment_status !== 'fulfilled' &&
    fulfillment_status !== 'partial'
  ) {
    console.log('CA order found!');
    
    const fulfillmentOrders = await shopify.order.fulfillmentOrders(id);
    console.log('fulfillmentOrders:');
    console.log(fulfillmentOrders.map(({id, status, assigned_location: {name}}) => ({id, status, name})));
    
    if (fulfillmentOrders.length === 1) {
      const fulfillmentOrder = fulfillmentOrders[0];
      console.log(`Moving fulfillment ${fulfillmentOrder.id} to ${californiaLocationId}`);
      await shopify.fulfillmentOrder.move(fulfillmentOrder.id, californiaLocationId);
    } else {
      console.log('Too many fulfillments; assuming a human has been at work, leaving it be.')
    }
  }
  
  return `ok`;
};