Well done!

You have completed Using npm as a Task Runner!

Preview

Overview

4:21 with Andrew Chalkley

In this video we'll take a brief overview to on task running with npm.

Download the project files to follow along with this workshop

Related Discussions

Have questions about this video? Start a discussion with the community and Treehouse staff.

Related Discussions

Have questions about this video? Start a discussion with the community and Treehouse staff.

[SOUND] Hello there, I'm Andrew, and 0:00

welcome to this workshop on using npm as a task runner. 0:04

A task is something that you need to do. 0:10

If you want to perform that task over and over again, 0:13

you'll save yourself a lot of time if you alternate the process. 0:16

Common web development tests include running test suites. 0:20

Compiling SaaS, TypeScript and CoffeeScript files. 0:23

Downloading assets of files from an external source that your package needs. 0:26

Starting a web server. 0:31

And starting a worker that goes through a queue of jobs, 0:33

like sending out emails or push notifications. 0:36

Popular jump script build tools like grunt and group are good for complex projects. 0:40

But you don't always need that power or 0:46

want to bother with the time consuming set up process that they require. 0:48

You can always turn to a full feature build system 0:53

later as your project evolves. 0:56

npm tests are called scripts, and 0:59

they're added to the scripts property of a project's package.json file. 1:01

Tasks have a name and a command, which is simply a string that's 1:07

executed on the operating system's command line when the task is run. 1:11

For example, you could echo out a message to the terminal, start up a web server, 1:16

or use a command line like mv to move files, or cp to copy files. 1:22

I'll show you a few examples in a moment. 1:28

Once you have the script added to the package.json file, you can run it simply 1:32

by typing npm run, the name of the script in your computer's command line tool. 1:36

For example, if you had a task named test, you'd run it by typing npm run test. 1:43

Or if I had a script named compile, that compiles CSS files, 1:51

I'd run it with npm run compile. 1:55

I'll focus on two types of task with MPM. 1:59

Default, or built-in tasks, and arbitrary tasks. 2:01

Built-in tasks are those that are common to most projects. 2:06

An example of a built-in task is "test". 2:11

Built-in tasks do not require the run command. 2:14

So npm run test can also be ran as npm test. 2:18

That saves a couple of keystrokes every time you want to run your tests. 2:24

Arbitrary tasks are those that you can name yourself. 2:28

They require npm’s run command. 2:32

Since there's no built-in compile task, if you added your own 2:35

script with that name, you'd read it like this, npm run compile. 2:40

Not all JavaScript applications will need custom or arbitrary tasks like this, 2:46

since the built-in task cover many of the most common situations. 2:52

Here's the simple project we're building in this video. 2:56

Dice Simulator 2015 is the latest craze. 3:00

You click the button and it rolls the dice. 3:03

This project is a front end project. 3:06

When I say we'll be building this, I don't mean that we'll be programming this. 3:09

All the programming has been done, but 3:14

we'll be getting the project ready to deploy. 3:16

Open up the associated work space with this video and we'll get going. 3:19

Let's take a look at the start point of this project. 3:24

We have a srcc folder or source folder. 3:27

A test folder, with a simple test for this application. 3:31

And we can use npm's built in test task for this. 3:36

Let's jump in quickly to the package.json file and see what's going on in there. 3:40

We'll be using Mocha as our test library and 3:47

UglifyJs to combine our JavaScript files into one app.js file. 3:50

The scripts object has a test task. 3:56

If you don't specify your test, it prints out, Error: no test specified, and 4:00

it exits with a 1, meaning something went wrong. 4:05

Computer programs successfully run exits with the code of 0. 4:08

The thing that's wrong here, is that we have no test set up. 4:14

We'll do that in the next video. 4:18

You need to sign up for Treehouse in order to download course files.

You need to sign up for Treehouse in order to set up Workspace