How to use AliExpress Affiliates with NodeJS

I have created an Affiliate Links project called FinDrop.link where I can retrieve products form AliExpress based on dropshipping URLs or images. Everything was perfect until I have faced a problem when I was close to wrap up the project.

The problem came when I tried to use my Affiliate Account from AliExpress to tag my Affiliate ID to each link, something that sounds simple but it has been a headache since I started investigating how to do it.

Here I drop a quick tutorial on how to get affiliate links from actual AliExpress links.

1. Create an account on portals.aliexpress.com
2. Get your app key, and secret key
3. Create a new affiliate tracking ID in Portals
4. Create a server side function that looks like this:

import axios from 'axios';
import * as crypto from 'crypto';

const APP_KEY = 'YOUR_APP_KEY';
const SECRET_KEY = 'YOUR_SECRET_KEY';

function getAffiliateLink(link: string) {
  const signMethod = 'sha256';
  const affiliateLinkMethod = 'aliexpress.affiliate.link.generate';

  // A timestamp is needed to use their API
  const timestamp = new Date().getTime();

  // Affiliate link parameters (Replace with your affiliate tracking ID)
  const trackingId = 'YOUR_AFFILIATE_TRACKING_ID';
  
  // Include the signature in your API request
  const url = 'https://api-sg.aliexpress.com/sync';
  const params = {
    app_key: APP_KEY,
    method: affiliateLinkMethod,
    timestamp: timestamp,
    v: '2.0',
    tracking_id: trackingId,
    promotion_link_type: 0,
    source_values: link,
    sign_method: signMethod,
  };

  // Sort all parameters and values according to the parameter name in ASCII table
  const sortedParams = Object.keys(params).sort().reduce((acc, key) => {
    acc[key] = params[key];
    return acc;
  }, {} as Record<string, string>);

  //  Concatenate the sorted parameters and their values into a string
  const sortedParamsString = Object.entries(sortedParams)
                                   .map(([key, value]) => `${key}${value}`)
                                   .join('');

  // Create the signature using HMAC-SHA256
  const signature = crypto.createHmac(signMethod, SECRET_KEY)
                          .update(sortedParamsString)
                          .digest('hex').toUpperCase();

  // Add the signature to the parameters
  params['sign'] = signature;

  try {
    const data = (await axios.get(url, { params })).data;
    // You will get back a JSON with the affiliate links
  } catch (error) {
    console.log(error);
  }
}

I hope it helps you, and you can save some time.