Yuri Mednikov

Tag: Backend development

Some thoughts on server side validation with Vertx and a bit of Vavr

Eclipse Vertx is a robust technology to build reactive microservices or serverless functions. When you develop such applications, the role of server side validation rises. In traditional web applications we combine both client-side…

Server side validation in Javalin

When you are working on any somehow complex application, you need to enable validation. For example, if user submits a form or a request, your app should check, that data is in an…

Exception handling in Clojure

In some form or another, but exceptions exist in almost any languages. Due to the fact, that Clojure actually runs on JVM, it inherits its exception system from Java. From a technical point…

Home made JWT authentication for Javalin

An authentication with tokens became a must-have feature for modern web apps. It suits natively to single page applications and mobile applications. While Spring is de facto standard in Java ecosystem, there are…

Make use of Vertx-junit5

Eclipse Vertx is perfectly asynchronous framework, so testing its components require a bit more work, than with “old school” synchronous applications. The main actor here is verticle, that is defined as independent unit…

Secure Webflux API endpoints with HandlerFilterFunction

In the previous post we have already talked about authentication in Spring Webflux. We implemented a component, that contains a required business logic to process login and signup, and to issue JWT. However,…

Simple email notification microservice using Vertx

Almost any more or less complex application has to deliver notifications. As usual, it is done via traditional emails, especially in cases of password reset messages or transactional notifications etc. There is a…

Testing Spring reactive services

Unit tests serve to verify individual components, mostly on business logic level, and to ensure that components perform as expected. In Spring Webflux apps this level is a level of services. Here we…

Error handling in Spring Webflux

The topic of error handling in web applications is very important. From a client perspective it is essential to know on how was the request proceeded and in case of any error is…

Two-factor authentication for Spring Webflux APIs

Multi-factor authentication became a common practice for many cases, especially for enterprise ones, or those that deal with sensitive data (like finance apps). Moreover, MFA is enforced (especially in the EU) by law…