Automate weekly sales reports with Node.js

A retail customer spends three hours every Monday morning pulling data from websites, e-commerce platforms, and accounting software into an Excel file. Here is how we automated that.

Gathering data from sources

Each source has its own module, returning the same format: date, channel, revenue, order count. Adding a new source simply requires writing another module.

const sources = [woocommerce, marketplace, accounting];
const rows = (await Promise.all(
  sources.map(s => s.fetchWeek(lastMonday))
)).flat();

Aggregation and verification

Before sending, the script compares the total revenue with the previous week. If there is an unusual discrepancy, the report is flagged with a warning for the recipient to double-check the data source.

Delivering on time

A cron job runs at 7 AM every Monday, generating the Excel file and emailing it to the management board. No dedicated server is needed—a serverless function is enough.

Start small

Do not try to automate everything at once. Pick the most repetitive report, automate it, and then gradually expand.