MySQL, PostgreSQL, and many more (even HTTP API)!

Whether you need to send data from your database to mobile or insert data from your mobile to the database, today I will show you how you can do that in 5 minutes.

The final result of the application

Our MySQL database looks like this.

Let me show you its negative impact on poorly written HTTP Server (Express Framework) in Node.Js.

We build spectacular apps, check

It always starts with an interesting prediction that our new server will be “small and simple”.

And yet, as most of the predictions, even this one will soon be doomed.

It all starts with this boilerplate code


The first use case is quite simple. When our server receives a login request from a client it will call the external HTTP API and when everything goes well it will send the 200 status code response to the end user.

We are building middleware. This server…

These days a lot of people is using Jest’s snapshot testing on a daily basis. I will show you reasons why I stopped.

We build spectacular apps, check


We changed a little bit of code and it blew off half of our tests. The problem is that these snapshots are highly coupled with our implementation and as we all know, coupling is one of the biggest pain in software development.

How coupled you asked?

Imagine we have a component and we created a new div container because of a new design requirement. …

Do your tests fail even with a little change of code? Do you mock heavily? Are you testing function calls and component state all the time? Well, you probably doing it wrong.

We build spectacular apps, check

I have read a lot of articles about how to test React components and most of the time I felt like there should be a better way. In this article, I would like to address some common issues with help of Jest and Enzyme.

So let's begin with the most important advice.

Test behavior, not implementation details!

Look at the example below.

At first, it seems…

In this article, we are going to look at the SOLID principles and how to apply them in the React.

For the sake of simplicity, I will not provide the full implementation of some components. So let's begin.

Single Responsibility Principle

First is the Single responsibility principle. This principle tells us that module should have one and only one reason to change.

Let’s imagine we are trying to build an application which displays users in a table.

We have a component which has a user list in the state. We are fetching users from some HTTP endpoint and each user is editable…

Tomáš Gold

Software Developer, focusing on clean code and JavaScript technologies.

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