How to send a PDF file to a WhatsApp user in Node.js

This article shows you how to send a document (e.g. a PDF file, an MP4 file, a WAV file, etc.) to a registered WhatsApp user in Node.js (JavaScript).

Before the recipient can receive your WhatsApp message, she MUST register with the WhatsMate WA Gateway. Instructions are available on the official site. Unregistered users will never receive messages from the Gateway.

To send a WhatsApp message containing a PDF file in Node.js, do this:

First, learn how to send a simple text message on the official site.
With the above knowledge, you can now download our sample code.

Locate the file nodejs/send-pdf-individual.js.

	#!/usr/bin/env node

	var http = require('http');
	var fs = require('fs');

	// Put down your own client ID and secret here:
	var instanceId = "YOUR_OWN_GATEWAY_INSTANCE_ID";
	var clientId = "YOUR_OWN_CLIENT_ID";
	var clientSecret = "YOUR_OWN_SECRET_ID";

	var jsonPayload = JSON.stringify({
	number: "12025550108", // FIXME
	document: fs.readFileSync("../assets/subwaymap.pdf").toString('base64'), // FIXME
	filename: "anyname.pdf", // FIXME
	caption: "Hope you like it" // FIXME. caption is optional. Can be null.
	});

	var options = {
	hostname: "api.whatsmate.net",
	port: 80,
	path: "/v3/whatsapp/single/document/message/" + instanceId,
	method: "POST",
	headers: {
	"Content-Type": "application/json",
	"X-WM-CLIENT-ID": clientId,
	"X-WM-CLIENT-SECRET": clientSecret,
	"Content-Length": Buffer.byteLength(jsonPayload)
	}
	};

	var request = new http.ClientRequest(options);
	request.end(jsonPayload);

	request.on('response', function (response) {
	console.log('Heard back from WhatsMate WhatsApp Gateway:\n');
	console.log('Status code: ' + response.statusCode);
	response.setEncoding('utf8');
	response.on('data', function (chunk) {
	console.log(chunk);
	});
	});

view raw send-pdf-individual.js hosted with ❤ by GitHub

Study the Node.js source code and customize the TODO/FIXME lines.
- Among other things, put down YOUR OWN number as the recipient. You can’t send messages to strangers because we are against SPAMMERS.
Change to the directory containing the script: cd nodejs
Run the script to send yourself the first image: ./send-pdf-individual.js

Happy coding :)