Stream -> promise -> stream

gistfile1.js

var lifestyle = require('lifestyle');
var through2 = require('through2');

var client = new lifestyle.FinnClient('http://api.finn.no/iad/');

var mapToAd = through2.obj(function (adId, encoding, callback) {
	client.getAd(adId).then(function(ad) {
		this.push(ad);
	}.bind(this), function(err) {
		console.error('YIKES, GOT ERROR!', err);
	}).finally(callback);
});

var pluckTitle = through2.obj(function (ad, encoding, callback) {
	this.push(ad.title);
	callback();
})

console.log('Enter any adId...');

process.stdin
	.pipe(mapToAd)
	.pipe(pluckTitle)
	.pipe(process.stdout);