In this article, we go through the basics of TypeORM migrations. It includes explaining why they are important & how to write them with Postgres. | Continue reading
In this article, we cover creating relationships in Postgres with TypeORM, including One-To-One, One-To-Many with Many-To-One & Many-To-Many. | Continue reading
The basics of creating an Express Postgres project with TypeScript and TypeORM. Setting up a Docker configuration with pgAdmin, connecting to the database. | Continue reading
In this article, we covered the basics of processing data with the MongoDB aggregation framework using, for example, $group, $lookup and $addField. | Continue reading
Registering and logging in users in a Typescript Express application using passwords hashed with bcrypt and JSON Web Tokens (JWT) | Continue reading
Not always everything goes perfectly, you need to expect the unexpected. To prepare for that, we cover Express error handling and incoming data validation. | Continue reading
In this part of the Express TypeScript tutorial, we cover using Express MongoDB with Mongoose. We also learn the concept of environment variables. | Continue reading
In this article we cover the very basics of building RESTful applications with TypeScript Express. It covers middleware, routing and controllers. | Continue reading
Hello! Today we tackle a very interesting topic, which is recursion. The article describes its main principles and dives deeper to uncover how does it work under the hood of the language, covering execution context and the call stack. Let’s go! JavaScript recursion Recursion An a … | Continue reading
There is a high chance that you’ve stumbled across the JavaScript eval function. It is a common knowledge that in JavaScript, eval is something that is a bad practice. Have you ever wondered how it works and why exactly a lot of people discourage it? This article covers that and … | Continue reading
Mistakes happen. That’s a given. According to Murphy’s law, whatever can go wrong, will go wrong. Your job, as a programmer, is to be prepared for that fact. You have a set of tools that are prepared to do precisely that. In this article, we go through them and explain how they w … | Continue reading
In this article, we explain what Cross-Origin Resource Sharing (CORS) is and how to avoid errors from the viewpoint of the frontend & backend. | Continue reading
Nowadays, JavaScript is often used to make Ajax requests. There are a lot of libraries that can do that for us, for example, axios or jQuery. Both of them use XMLHttpRequest (XHR). It differs from the relatively new Fetch API that was introduced a few years ago. This article expl … | Continue reading
In this article, we cover ways to join strings. Even though it includes old methods of concatenating strings, we focus on template literals. Here you can learn how they work and how to expand their functionality with tags. Let’s go! Before template literals Back in the days, we d … | Continue reading
The basics of how JavaScript array work under the hood. Explaining the type that the array value is, what are indexes, what is a maximum size of an array. | Continue reading
IndexedDB is another API meant for client-side storage. It is good for storing a significant amount of data, including files. IndexedDB is more suitable than WebStorage suitable for keeping structured data, and definitely more adequate for that than cookies. In this article, we g … | Continue reading
With the properties of objects, you can set more than just their values. In this article, you can learn what is the property descriptor and what you can achieve with it. Among other things, you can use getters and setters and the article also explains their concepts. Property des … | Continue reading
WebSocket is a protocol that makes two-way communication in real-time between the user and the server possible. A common use cases are chats and online multiplayer games. Today we cover implementing it both on frontend and backend. Let’s go! Explaining WebSockets WebSocket is a d … | Continue reading
1. JavaScript testing tutorial – part one. Explaining types of tests. Basics of unit testing with Jest2. JavaScript testing tutorial – part two. Introducing Enzyme and testing React components3. JavaScript testing tutorial – part three. Testing props, the mount function and snaps … | Continue reading
At the previous part of the tutorial, we’ve briefly covered the basics of unit testing. This time we will go further and start testing React with the Enzyme library. Thanks to the that, your application will be more reliable and it will be easier to avoid regression. Even though … | Continue reading
1. Webpack 4 course – part one. Entry, output and ES6 modules2. Webpack 4 course – part two. Using loaders to handle scss, image files and transpile JS3. Webpack 4 course – part three. Working with plugins4. Webpack 4 course – part four. Code splitting with SplitChunksPlugin5. We … | Continue reading
1. Webpack 4 course – part one. Entry, output and ES6 modules2. Webpack 4 course – part two. Using loaders to handle scss, image files and transpile JS3. Webpack 4 course – part three. Working with plugins4. Webpack 4 course – part four. Code splitting with SplitChunksPlugin5. We … | Continue reading
Today we will cover the development value of the mode property. It will automatically set the webpack configuration for you to make the development easier. Aside from that, we will also cover the wepback-dev-server and webpack-serve – Hot Module Replacement included. Let’s go! We … | Continue reading
1. Webpack 4 course – part one. Entry, output and ES6 modules2. Webpack 4 course – part two. Using loaders to handle scss, image files and transpile JS3. Webpack 4 course – part three. Working with plugins4. Webpack 4 course – part four. Code splitting with SplitChunksPlugin5. We … | Continue reading
1. Webpack 4 course – part one. Entry, output and ES6 modules2. Webpack 4 course – part two. Using loaders to handle scss, image files and transpile JS3. Webpack 4 course – part three. Working with plugins4. Webpack 4 course – part four. Code splitting with SplitChunksPluginHello … | Continue reading
After walking through the basic concepts of webpack, it is time to go deeper. This time we will cover something that is a great strength of webpack: loaders. First, we will learn how to use loaders that are available. This will include handling css, scss, image files and transpil … | Continue reading
Hello! Today we begin a webpack 4 course. We will start with the basic concepts of Webpack, with every part of the course going deeper. This time we will learn the basics of module bundling using ES6 modules. Webpack 4 provide default configuration, which we will go through. Let’ … | Continue reading
In the previous article, we’ve learned what events are and how to work with them. This time we will dive a bit deeper into them, explaining in more details how do they work. We will go through the event object and create our own, custom events. We will also simulate some native e … | Continue reading
JavaScript is a language, where events play a big role. In this article, we will talk about how they work. It includes different ways of listening to them and how they propagate. On the way we will cover some of mechanics from under the hood of JavaScript and browsers. We will al … | Continue reading
In JavaScript, the memory taken by the values held by the variables is automatically freed when they are not used anymore. This is done by the garbage collector to free up space. How can we benefit from knowing how it works and therefore how to write better code? Let’s find out! … | Continue reading
Web Storage API is used to store data in the browser and was introduced in HTML5. It bringed us localStorage and sessionStorage. At the first glance, they seem similar. There are some important differences between them though, which is what we will talk about today. You will lear … | Continue reading
Webpack 4 brought us some changes. Among things like faster bundling, it introduced SplitChunksPlugin, which made CommonsChunksPlugin obsolete. In this article, you will learn how to split your output code to improve the performance of our application. The idea of code splitting … | Continue reading
Functions are one of the most basic features of JavaScript. Have you ever wondered how exactly do they work? After all, they are just a special kind of objects. If you are curious, dig into them with me in this article! The basics of functions Speaking practically, a function is … | Continue reading
Mastering your tools as a developer is a very important thing. One of them is Node Package Manager – and quite a crucial one for a JavaScript developer. Having a better understanding how dependencies work will improve your workflow greatly and help to avoid many problems both for … | Continue reading
We covered quite a few features of regex so far. There is a lot more, though. Today we will deal with more advanced concepts, like groping and cover more of the RegExp object features in JavaScript. We will also learn how to use some of the features that ES6 brought us. Let’s go! … | Continue reading
Hello again! Today we are back to regular expressions in JavaScript. If you are new to them, check out the first part of the course. This time we will learn how to write more elegant patterns and define the position of searched strings. The shorter way to define repetitions Recen … | Continue reading
Regular expressions (regex) are sequences of characters defining a search pattern. Since it can be extremely useful in programmers everyday life, it was implemented into JavaScript. In this series of articles, I will show you how it works and what are its real-life usages. Hopefu … | Continue reading