I'm moving this file contents to the repository wiki

DOING

Technologies that I'm tryng to learn right now.

• dotenv
• knex.js
• TypeORM(Not Using)
• Jest

dotenv

Dotenv is a zero-dependency module that loads environment variables from a .env file into process.env.

Basically dotenv's purpose is for you to be able to use environment variables inside your code.

This environment variables are saved in a file at the project root folder caller .env.

Setup and Use

Run yarn add dotenv to install it.

Now you'll create a new .env file at the root off your project. This is the file syntax:

PORT=3333

# DATABASE
CLIENT=postgres
USER=user
MY_VARIABLE=variableText

---

To use dotenv you'll need to call it as soon as possible in your project

require('dotenv').config()

Or pass some options for multiple .env files

require('dotenv').config({
  path: process.env.NODE_ENV === 'test' ? '.env.test' : '.env.dev'
})

If you're using import, dotenv recommends that you use preload.

Edit your package.json file:

"scripts": {
  "dev:server": "ts-node-dev --require dotenv/config --respawn --transpileOnly src/server.ts",
  "dev:serverOld": "ts-node-dev --respawn --transpileOnly src/server.ts",
}

The require of dotenv is done in the script --require dotenv/config.

You also can call the .env file of your choice by adding dotenv_config_path=.env to your script:

{
  "scripts":{
    "dev:server": "ts-node-dev --require dotenv/config --respawn --transpileOnly src/server.ts dotenv_config_path=.env",
    "dev:serverOld": "ts-node-dev --respawn --transpileOnly src/server.ts",
  }
}

I just want to remember that you should always put your .env files inside .gitignore.

Although dotenv doesn't recommend using multiple files, I reckon that it makes some things easier, but you still should avoid it as much as possible.

How I learned

• https://github.com/motdotla/dotenv
• https://www.youtube.com/watch?v=2G_mWfG0DZE

knex.js

A batteries-included, multi-dialect query builder for Node.js.

What you'll use to manipulate your databases.

Setup

Run yarn add knex to install.

Run yarn add pg to add database drivers.

// DATABASE_URL env should follow this format:
// postgres://user_name:password@ipaddress:port/table
// Example: postgres://jimmy:password@localhost:5432/pg_database

Create a file named knexfile.ts in the root folder.

Example:

import dotenv from 'dotenv'
import path from 'path'
dotenv.config()

module.exports = {
  development: {
    client: process.env.DB_CLIENT,
    connection: process.env.DB_URL,
    migrations: {
      directory: path.resolve(__dirname, 'src', 'database', 'migrations')
    }
  }
}

Create a file named connection.ts inside src/database.

Example:

import knex from 'knex'

const connection = knex({
  client: process.env.DB_CLIENT,
  connection: process.env.DB_URL
})

export default connection

Knex ready for use 👍

Migrations

You can run yarn knex migrate:make migration_name to create migration files.

Example:

import Knex from 'knex'

export async function up (knex: Knex): Promise<any> {
  return knex.schema.createTable('champion', table => {
    table.increments('id').primary()
    table.string('name').notNullable()
  })
}

export async function down (knex: Knex): Promise<any> {
  return knex.schema.dropTable('champion')
}

To run the migrations create the script.

{
  "scripts": {
    "knex:migrate": "knex --knexfile knexfile.ts migrate:latest"
  }
}

You can run it like this yarn knex:migrate or set the environment yarn knex:migrate --env staging.

Seeds

How I learned

• http://knexjs.org/
• http://knexjs.org/#esm-module-interop
• https://github.com/knex/knex
• https://www.youtube.com/watch?v=U7GjS3FuSkA&t

Setup

Jest

Jest is a delightful JavaScript Testing Framework with a focus on simplicity.

Setup

Run yarn add jest @types/jest ts-jest -D to install it.

Now add jest to the .eslintrc.js file, it should look like this now:

env: {
    es6: true,
    node: true,
    jest: true
  },

Now for the configuration run yarn jest --init.

Would you like to use Jest when running "test" script in "package.json"? Y

Choose the test environment that will be used for testing node

Do you want Jest to add coverage reports? y

Automatically clear mock calls and instances between every test? y

It creates the jest.config.js file.

You'll have to make some changes to the file.

  collectCoverageFrom: [
      'src/**/*.ts'
    ],

  coverageDirectory: '__tests__/coverage',

  transform: {
    '^.+\\.ts$': 'ts-jest'
  },

Now you can create a folder __test__ at the root of the project and place all the tests inside it.

I'll put one example here.

exaple.spec.ts

test('sum two numbers', () => {
  expect(1 + 1).toBe(2)
})

Now you can simply run with yarn test.

TypeORM

TypeORM is an ORM that can run in NodeJS, Browser, Cordova, PhoneGap, Ionic, React Native, NativeScript, Expo, and Electron platforms and can be used with TypeScript and JavaScript (ES5, ES6, ES7, ES8).

Setup

Things to install:

For the ORM yarn add typeorm yarn add reflect-metadata yarn add @types/node -D

Database driver yarn add sqlite3 -D `yarn add pg

Files configuration:

Your tsconfig.json should have this lines.

  "compilerOptions": {
    "lib": [
        "es5",
        "es6"
    ],
    "target": "es5",
    "module": "commonjs",
    "moduleResolution": "node",
    "outDir": "./build",
    "emitDecoratorMetadata": true,
    "experimentalDecorators": true,
    "sourceMap": true
  }

Create a file named ormconfig.json

{
   "type": "sqlite",
   "database": "database.sqlite",
   "synchronize": true,
   "logging": false,
   "entities": [
      "src/entity/**/*.ts"
   ],
   "migrations": [
      "src/migration/**/*.ts"
   ],
   "subscribers": [
      "src/subscriber/**/*.ts"
   ],
   "cli": {
      "entitiesDir": "src/entity",
      "migrationsDir": "src/migration",
      "subscribersDir": "src/subscriber"
   }
}

This is a basic configuration. Create a folder named entity and other named migration inside the src/ folder.