**Pain Free Mocking with Jest** teaches you how to effectively and painlessly test JavaScript applications with Jest. You'll start by learning how to write unit and integration tests as well as the 'How', 'What', and 'When' of Mocks, Stubs, and Spies. Then we'll move to more advanced technique and strategies you'll be using for the rest of your career, including how to have a hollistic approach to testing and how to automatically add your tests in the development lifecycle.

### The Issue With Unit Testing & Mocks

Writing unit tests has always been equal parts important and confusing. 

While writing your first unit test is simple and easy, the learning curve becomes very steep very quickly once you have to test actual real-life scenarios. 

Because suddenly, you have to know how to **mock a database call** or **spy an HTTP request** or **stub a 3rd party API with a security token**. When you have to test real-life scenarios like that, things become much more complex than they initially seemed.

With every test case being different from the next one, and with Mocks not being used anywhere else in coding except for testing, it's hard to find quality information online. Every answer is different from the next one and is aimed for an ultra-specific scenario that won't necessarily apply to any other case, including yours. 

Instead of making things clear, this confuses things even further. 

### How "Pain Free Mocking with Jest" Helps:

"Pain Free Mocking with Jest" is designed to make testing painless by helping you understand once and for all the 'How', 'What', and 'When' of Mocks, Spies, and Stubs using the Jest testing framework.

You will learn how to write simple and complex test cases, utilize Jest's mocking capabilities, and gain hands-on experience with real-world testing scenarios that involve Databases, HTTP requests, and 3rd Party APIs. 

By the end of the course, you'll feel confident using Mocks, Spies and Stubs in any scenario you may need them. You'll have all the knowledge and tools you need to create complete test suites and confidently test JavaScript applications *with* mocking *without* headaches.

### Course Content Overview

Course Overview:
Total Modules: **6**
Total Lessons: **37**
Total Video Runtime: **2 hours, 28 minutes**

### Summary:
- Build and test a Node.js REST API application with authentication features like 'Sign Up' and 'Sign In'. 
- Learn how to test everything from simple functions all the way to Controllers that interract with 3rd party web services.
- Learn the 'What', 'How', and 'When' of Mocks, Spies, and Stubs.
- Learn to see your application code in testable units. 
- Write integration tests for HTTP endpoints, controllers, middleware functions, and 3rd party integrations.
- Create Git hooks to run unit tests before each commit 
- Build a CI pipeline using Github Actions to automate running integration tests on each git push to Github.

Learn to confidently test JavaScript applications and mock dependencies using Jest, the pain-free way. 

Understand how to painlessly use Mocks, Spies, and Stubs to test any part of your application, without worrying about Databases, APIs and Security Tokens. 

After finishing this course (which only takes a single afternoon), you'll feel confident in your testing skills because you'll have all the knowledge and tools you need to effectively and painlessly test even complex applications in the real world without headaches.

Pain Free Mocking with Jest

---
title: Separate database for testing purposes
description: How to use a separate test database instance for testing purposes
privateVideoUrl: https://stream.mux.com/s1ul502Y8Bl7TjiqHH1Nf7pqhXLzrDTX01WfO1Z3aq00JE.m3u8
isPublicLesson: false
---

# Implementing Separate Database Instances for Testing in Node.js Applications

## Introduction

Software development requires meticulous testing and experimentation. To ensure the stability of the production database while making changes, it is crucial to establish separate database instances for development and testing purposes in a Node.js application. This article will guide you through the process, enabling you to create a safe environment for trial and error without compromising your production system's stability.

## Setting Up the Environment

The first step is to install the necessary dependencies for the application. If you're developing a Node.js application, you can use the terminal to install `express` and `dotenv`.

```shell
npm install express dotenv
```

To manage environment variables effectively, we'll utilize the popular library known as `dotenv`. Create a file named `.env` in the root of your project, which will primarily contain the MongoDB URI used by your application.

In addition, create two more environment configuration files: `test.env` and `dev.env`. These files will hold the specific environment variables for your development and testing environments respectively.

```shell
// .env
MONGODB_URI=mongodb://localhost:27017/myrecipe
```

```shell
// test.env
MONGODB_URI=mongodb://localhost:27017/myrecipetest
```

```shell
// dev.env
MONGODB_URI=mongodb://localhost:27017/myrecipedev
```

## Properly Configuring the Testing Environment

In the testing environment, we'll use Jest as our testing framework. Jest automatically changes the `NODE_ENV` environment variable to `'test'` during test execution. This functionality helps distinguish between the development and testing environments.

How to use a separate test database instance for testing purposes