Typescript Project Setup Guide

This is an empty template for creating TypeScript projects. It also includes ESLint and Jest.

The easiest way of creating a new project is by forking this into a new GitHub repository:

• fork this repo on GitHub by pressing the fork button on the upper right side.
• choose the account you want your fork (your new repo) to be placed
• click on the settings button in your forked repo and change the name e.g. to 'myproject'
• open a console / bash and get a local copy using `git clone https://github.com/youraccount/yourproject'
• change the package.json to your needs
• ...enjoy with your new project :)!

Why forking?

Have a look at this fork. In the meanwhile the main repo has changed. In the forked repo you see something like this:

This branch is XYZ commits behind software-developer-org:master. | Pull request | Compare

Now you can go to 'Compare' and click on 'switching the base for your comparison' and you can create a pull request for getting all the changes into your fork.

Duplicating a repository

• go to your GitHub account, create a new repository e.g. myprojects-typescript-template
• open Git Bash
• create a bare clone of the repository

$ git clone --bare https://github.com/software-developer-org/typescript-template

• navigate to the that repository (a bare clone repo will end with .git!)

$ cd typescript-template.git

• mirror-push to your new repository on GitHub

$ git push --mirror https://github.com/_yourusername_/myprojects-typescript-template.git

• remove the temporary local repository

$ cd ..
$ git -rf typescript-template.git

Why duplicating?

With git clone --bare you will get all of the tags copied, local branches master (HEAD), next, pu, and maint, no remote tracking branches. That is, all branches are copied as is, and it's set up completely independent, with no expectation of fetching again. Any remote branches (in the cloned remote) and other refs are completely ignored. Your new GitHub repository will now not be affected by changes in the initial repo, like forking, anymore.

Setup tool chain

Git

Install and configure git following this git-started as a basic tutorial.

In case you are new to git: step back, take your time, and work through the tutorial at your own speed! git is a tool you will work with on a daily basis. The better you understand and dive deeper into it, the more productive you will be on your daily business!

Once you have mastered the basics of git followed these intermediate git-bootcamp exercises.

Node.js

You can find the latest version for your system at nodejs.org. There are two versions:

• a long time support version (LTS): which should be used on production
• latest version: if you are curios about the latest Node features

If you are not implementing in Node, or do just TypeScript, then go for the LTS. This will also make your life easier when integrating other projects or apis.

Node Package Manager (npm)

NOTE: If you install Node.js it also includes npm.

npm is (a) a registry where you can find all open source packages here and (b) a command line tool (CLI) for installing node packages from this registry (and others).

Visual Studio Code (aka VSCode/ vs code)

Visual Studio Code is a lightweight but powerful source code editor. You can download the latest version on code.visualstudio.com

VSCode Plugins

VSCode has some realy helpful extensions. For intalling extensions follow these instructions. We recommend the following extensions:

• ESLint
• Prettier ESLint
• Prettier- Code formatter
• Git History

The easiest way to install them is to search for each in the vscode extention tab (Ctrl+Shift+X)

Getting Started

Install node packages

Your project configuration is defined in the Node configuration file 'package.json'. In this file all the required Node packages for this project are defined. These packages will be installed by the folling CLI command. Open your console and enter:

> npm install
# the following is only output...
npm WARN [email protected] No repository field.
npm WARN optional SKIPPING OPTIONAL DEPENDENCY: [email protected] (node_modules\fsevents):
npm WARN notsup SKIPPING OPTIONAL DEPENDENCY: Unsupported platform for [email protected]: wanted {"os":"darwin","arch":"any"} (current: {"os":"win32","arch":"x64"})

added 621 packages from 373 contributors and audited 622 packages in 13.291s

21 packages are looking for funding
  run `npm fund` for details

found 0 vulnerabilities

All installed packages will appear in the node_modules folder. Every time the package.json is updated, this folder can be updated using npm install.

Jest

Jest is used for unit testing your code. You can find an example file with the corresponding test in this repo.

All tests can be started by:

npm  run test

Note: npm run test points to a script named 'test' as defined in package.json. In this case it is a shortform for npx jest.

Jest allows a TestPathPattern (see help using npx jest --help). Examples:

# run all tests containing the pattern 'example-code'
npm run test example-code

# run all tests containing the pattern 'array-exercise'
npm run test array-exercise

# run all tests ending with test.ts
npm run test *test.ts

Debugging in VSCode

You can also use Jest to debug your code. The config is stored in .vscode/launch.json.

For debugging:

• use the debug tab (Ctrl+Shift+D),
• select the 'Debug Jest Tests' option in the upper left corner, and
• press the green start button this will run all tests in debug mode.

If you want to run a single test open your launch.json file (CTRL+SHIFT+P to open a file) in the .vscode folder and uncomment the filename:

{
...
    "configurations": [
...
        {
...
            "runtimeArgs": [
...
              //"<filename>", // uncomment in case only one test should be started
...
            ],
...
}

For more information on how to use jest visit jestjs.io

ESLint & Prettier

You can use these two basic config files in this repo:

• .eslintrc.js
• .prettierrc

If you want to personalise your config visit the following sites for more information:

• prettier config
• eslint config

Scripts

We added three other scripts in the package.json file.

Two scripts for eslint:

• To check your projekts formating and errors use the comand:

npm  run lint

• And with this second command elsint will fix al autofixable problems:

npm  run fix

And one for typescript:

This command creates a new folder and compiles your projekt files from typescript into plain javascript.

npm  run build

It also clears any previously builded files bevor compiling.

New to JavaScript and TypeScript?

Start coding and open the array-exercise-001.test.ts file. Check out these resources:

• additional resources on JavaScript check the Mozilla Developer Network (MDN, see below).
• especially the reference on Arrays on MDN

Resources

• Mozilla Developer Network - JavaScript
• JavaScript tutorials on W3Schools
• YouTube: Functional Programming with JavaScript