RestClient in Spring Boot – Modern Alternative to RestTemplate (Deep Dive into Fluent API, Internals & Interceptors) In the previous part, we understood why RestTemplate is no longer the best…
Synchronous Communication Between Microservices in Spring Boot (OrderService ↔ ProductService using RestTemplate & RestClient) In a real-world microservices architecture, services rarely live in isolation. They constantly need to talk to…
Role-Based Authorization in Spring Boot using @PreAuthorize and @PostAuthorize In modern Spring Boot applications, security is not just about authentication (who you are) but also about authorization (what you…
OAuth 2.0 vs OIDC – Complete Guide with Stateless Spring Boot Implementation OAuth is one of the most misunderstood topics in security. Most developers use it daily (Google login,…
OAuth 2.0 – Complete Guide (High Level Design) What is OAuth 2.0? OAuth stands for Open Authorization. It is an authorization framework, not authentication. It allows: Secure third-party applications…
JWT Authentication in Spring Boot – Full Implementation Guide We will implement: User Registration Token Generation (Login) JWT Validation Filter Custom Authentication Provider Secured APIs Refresh Token Step 1…
JWT (JSON Web Token) – Complete Notes What is JWT? JWT (JSON Web Token) is a stateless authentication mechanism used to securely transmit information between parties as a JSON…
Basic Authentication in Spring Security – Complete Guide Basic Authentication is one of the simplest authentication mechanisms supported by Spring Security. It is easy to implement, widely supported, and…
Form Login Authentication in Spring Security – A Complete Guide Form Login Authentication is the default authentication mechanism in Spring Boot Security. It is simple, powerful, and widely used…
Common Web Security Attacks Every Spring Developer Must Know Before diving into Spring Security, it’s important to understand the most common web application attacks. These vulnerabilities exist in almost…
