app-promise.js

const yargs = require('yargs');
const axios = require('axios');

const argv = yargs
      .options({
        a: {
          demand: true,
          alias: 'address',
          describe: 'Address to fetch weather for',
          string: true
        }
      })
      .help()
      .alias('help', 'h')
      .argv;

var encodeAddress = encodeURIComponent(argv.address);
var geocodeUrl = `https://maps.googleapis.com/maps/api/geocode/json?address=${encodeAddress}`;
axios.get(geocodeUrl).then(res => {
  if (res.data.status === 'ZERO_RESULTS') {
    throw new Error('Unable to find that address.');
  }
  var lat = res.data.results[0].geometry.location.lat;
  var lng = res.data.results[0].geometry.location.lng;
  var weatherUrl = `https://api.darksky.net/forecast/bd24b48f09651451b6de3f8c53396351/${lat},${lng}`;
  return axios.get(weatherUrl);
}).then((response) => {
  var temperature = response.data.currently.temperature;
  var apparentTemperature = response.data.currently.apparentTemperature;
  console.log(`It's currently ${temperature}. It feels like ${apparentTemperature}`);
}).catch(e => {
  console.log(e);
  if (e.code === 'ENOTFOUND') {
    console.log('Unable to connect to API servers.');
  } else {
    console.log(e.message);
  }
});