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ExpressJS Tutorial

Post data to a web server to automate your Office documents.

Tip

Download a Zip of tutorial files.

Prerequisites​

Download and install nodeJS v16+ from https://nodejs.org/.

Tip

run node --version from a terminal window to confirm installation.

Installation​

Create a project directory, make it your working directory, and run from a terminal window:

Terminal

npm init -y
npm i express
npm i @yumdocs/yumdocs

Getting started​

  1. Create a Word document named input.docx, type {{field}} and save it in the project directory.
input.docx
{{field}}
  1. In the same project directory, create a file named index.mjs and copy-paste:
import path from 'node:path';
import express from 'express';
import {YumTemplate} from '@yumdocs/yumdocs';

const INPUT = './input.docx';
const OUTPUT = './output.docx';

// Create an express app with a JSON parser
const app = express();
app.use(express.json());

// Handle posts to /yumdocs
app.post("/yumdocs", async(req, res, next) => {
    try {
        const t = new YumTemplate();
        const i = path.resolve(process.cwd(), INPUT);
        const o = path.resolve(process.cwd(), OUTPUT);
        await t.load(i);
        await t.render(req.body);
        await t.saveAs(o);
        // res.download(o);
        res.sendStatus(200);
    } catch (error) {
        next(error);
    }
});

// Launch the web app
app.listen(3000, () => {
    console.log("Server running on port 3000");
});
  1. Open a terminal window in this project directory and run:
Terminal

node index.mjs

Tip

Change the value of "main" for index.mjs in package.json to run node . instead.

  1. Open another terminal window (keep the server running) and run the following request to simulate a browser:
Terminal

curl -X POST http://localhost:3000/yumdocs -H 'Content-Type: application/json' -d '{"field":"Anything you see fit"}'

  1. output.docx has been generated and the {{field}} placeholder has been replaced with Anything you see fit.
output.docx

Anything you see fit