/w1-node-ecosystem

Primary LanguageJavaScript

Setting up a Project with Node

Welcome to JSCRIPT 400 - Server Side Development with JavaScript

During class, we will be using repositories like these to develop skills and solidify concepts. I would recommend reading through the instructions before coming to class to prime yourself to the material.

Part of your homework assignment for each class will be to make a Pull Request against this repository. Your Pull Request should include answers to any questions in this document.

As we work together on this during class, I would encourage you to make comments next to code we write. Explain what is happening in your own words so that later you have those notes as a reference.

Core Learning Objective

  • Use NodeJS APIs to interact with files and the web

Sub-Objectives

  • Setup a basic NPM project
  • Run your project from the command line with scripts
  • Export and require your own files
  • Require and use core Node libraries
  • Install, require, and use packages from the web

Prereqs

To complete this lesson, make sure that node and npm is installed and can be run from the command line. My versions of each are as follows:

$ node -v
v12.2.0

$ npm -v
6.9.0

Instructions & Guiding Questions

  • Fork & Clone this repository

  • Question: What is the difference between forking and cloning a repository as opposed to just cloning a repository?

  • Your Answer: git fork - creates a safe environment for you to write code and create experiments without impacting the master branch. You could merge this code in later.

git clone - creates a copy locally for you to work in and keep track of the master remote repository.

  • Run npm init -y from the command line

  • Question: What does npm init do? How does the -y flag modify that command?

  • Your Answer:

It says yes to everything when you initiate a new node project and makes assumptions on certain fields about what should be filled out.

  • Take a look at the file that was generated by the previous command

  • Question: What is the purpose of the following keys? "name", "scripts", "license"

  • Your Answer:

  • name - Is the name of the project. Important if you plan to publish your package.
  • scripts - Is where you define any default and/or custom commands that are run at various times of your package lifecycle.
  • license - Is for if you need to have any special licensing for your project. It let's people know whether or not they are permitted to use it and if you are placing any special restrictions on it's use.
  • Create a .gitignore file

  • Question: What is the purpose of the .gitignore file? What is the significance of a "dot-file?"

  • Your Answer:

Using git as your version control system, you can create a .dot file such as .gitignore to tell git which file changes to not keep track of. Having a . in front of a file creates a hidden file. Typically want to hide things like node_modules, API key, etc.

  • Create an index.js file with the following contents: console.log('Hello, Node!')

  • Question: From the command line, how can you run this file?

  • Your Answer: In your terminal, you run node index.js

You would run node index.js

  • Run npm test from the command line

  • Question: What happens and how is this related to what is in the package.json file?

  • Your Answer:

It will display back npm ERR! Test failed. See above for for more details in your terminal. You would need to specify any test scripts here and it can print to the terminal any custom messaging you write.

  • Create a new "script" command called "start" that has the following value: node index.js

  • Question: What will you enter on the command line to run that script?

  • Your Answer:

npm start - default script

  • Change the name of your "start" script to "my-file"

  • Question: The same pattern will not work to try and run this script. How can you successfully get this script to run?

  • Your Answer:

    If you create a custom script, you have to add the run keyword before your custom script name.

  • Create a new file called profile.js. Inside the file, copy the following but replace <your-name> with your name:

    module.exports = "<your-name>";

    Add the following to your index.js file. Then, run your file.

    const profile = require("./profile.js");
console.log(profile);

  • Question: What gets logged? Why?

  • Your Answer:

It will log out the string with my name because I have exported it and made it available to be used elsewhere in the app.

  • Question: What is module.exports and what is its type in JavaScript? What is require and what is its type in JavaScript?

  • Your Answer:

It's an object. You can create an object or an array and then export it.

  • We can only export one thing from files when using Node. With that said, export both your name and your birthday from the profile.js file.

  • Question: What are some ways you can solve this problem?

  • Your Answer: You could declare a const object and export it like the following. This now makes it accessible elsewhere in your project.

const person = {
    name: 'Tom Workman',
    age: 1000,
}

module.exports = person
  • Add the following to your index.js file. Then, run your file. 
    const path = require("path");
console.log(path.resolve());

  • Question: What is path and where does it come from?

  • Your Answer:

Path is just a package that comes with Node. It's a module that is part of Node.

  • Question: What command can you run to install this package?

  • Your Answer:

Run npm i moment

  • On your own, use this package in the index.js file

  • Question: Do you need to use a ./ to require the package? Why or why not?

  • Your Answer:

Nope! Node knows to look for it in the package.json.

  • Move your profile.js file into a src/ folder. Update the path in your index.js file to ensure everything continues to work.

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