In the fourth part of this series, we’ve learned the basics of mocking API calls. However, there are often situations where we would like to test various more demanding cases. So, in this article, we implement more advanced examples on how to mock with Jest. Creating a simple React component Let’s start by creating a […]
When developing applications, data fetching is one of the most fundamental tasks. Despite that, there are some things to watch out for: one of them is race conditions. This article explains what they are and provides a solution using the AbortController. Identifying a race condition A “race condition” is when our application depends on a […]
A few days ago, React released version 18, which is not compatible with Enzyme. Furthermore, it probably is not achievable to use Enzyme with React 18. If you’re still using Enzyme, it is time to look into alternatives. The most popular option besides Enzyme seems to be React Testing Library. However, incorporating RTL requires a […]
As web developers, we should care about the privacy of our users. This article explains what the Referer header is and what information it exposes. We also learn to use the Referrer-Policy to control how many details the referer header should include. We can increase privacy and deal with some potential security issues by doing […]
When developing an application, we need to ensure that our users are safe from various attacks. Unfortunately, the web has a lot of mechanisms that can be abused. In this article, we explore the idea of iframes and underline the danger of clickjacking. We also learn how to deal with this problem using the X-Frame-Options […]
We’ve learned how to block certain cross-site-scripting (XSS) attacks in the previous article. We did that by disallowing our website from running JavaScript from unknown origins. Unfortunately, attackers might be able to upload malicious code into our application disguised as an image, for example. Then, they can take advantage of MIME sniffing to trick a […]
The security of our web application should be one of our primary concerns as developers. One of the threats we need to consider is cross-site scripting (XSS). This article explains the danger it poses and how we can fight it using a Content Security Policy (CSP) header. Cross-Site Scripting (XSS) With cross-site scripting (XSS) attacks, […]
We need to watch out for quite a few pitfalls when designing our architecture. One of them is the possibility of circular dependencies. In this article, we go through this concept in the context of Node.js modules and NestJS services. Circular dependencies in Node.js modules A circular dependency between Node.js modules happens when two files […]
So far on this blog, we’ve used the serial type to define autoincrementing ids for our tables. However, TypeORM started fully supporting identity columns very recently. Since PostgreSQL official recommends using them, it is a good moment to go through both approaches and compare them. Serial type The serial data type allows us to generate unique […]
Across this series, we emphasize code readability and maintainability. In part #52 of this course, we’ve gone through generating documentation with Compodoc and JSDoc. This time we look into the OpenAPI specification and the Swagger tool. You can check out an interactive demo prepared by the Swagger team. Introducing OpenAPI and Swagger With OpenAPI and […]
