#!/usr/bin/env node

const amqp = require('amqplib');

const args = process.argv.slice(2);

if (args.length === 0) {

console.log("Usage: rpc_client.js num");

process.exit(1);

}

async function main() {

const connection = await amqp.connect('amqp://localhost');

const channel = await connection.createChannel();

const correlationId = generateUuid();

const num = parseInt(args[0]);

console.log(' [x] Requesting fib(%d)', num);

const result = await new Promise((resolve) => {

// Consume from the Direct Reply-to pseudo-queue (noAck is mandatory)

channel.consume('amq.rabbitmq.reply-to', (msg) => {

if (msg.properties.correlationId === correlationId) {

resolve(msg.content.toString());

}

}, { noAck: true });

channel.sendToQueue('rpc_queue',

Buffer.from(num.toString()), {

correlationId: correlationId,

replyTo: 'amq.rabbitmq.reply-to'

});

});

console.log(' [.] Got %s', result);

await connection.close();

}

function generateUuid() {

return Math.random().toString() +

Math.random().toString() +

Math.random().toString();

}

main();