app-promise.js

This is the final code and uses axios to send and receive data via API.

Notes from the course

appendFile now appendFileSync

fs.appendFile(‘greetings.txt’, ‘Hello’);

To get rid of callback error; in node 7 or greater, you need to use:

fs.appendFileSync(‘greetings.txt’, ‘Hello’); or fs.appendFile(‘greetings.txt’, ‘Hello’, function (err) { if (err) { console.log(‘Unable to write to file’); } });

Installing NPM

npm init npm install (as usual add to .gitignore)

Installing nodemon

It’s a command line utility that gets executed from the terminal

Installing yargs

npm install yargs@4.7.1

const argv = yargs.argv;

usage = argv.”title”

var command = argv._[0];

Axios

if (response.data.stats === ‘something’) { throw new Error(‘Unable to fetch data from API servers’) }

The following is the basic error catch message (one catch for all promises, or individual error as above (or use both for specific errors for some, and generic errors for others.))

.catch((e) => { if (e.code === 'ENOTFOUND') { console.log('Unable to connect to API servers.') } else { console.log(e.message); } });