https://devops-monk.com/tags/jwt/Recent content in Jwt on Devops MonkHugoen-usSun, 03 May 2026 00:00:00 +0000https://devops-monk.com/tutorials/spring-boot/spring-security-jwt/Sun, 03 May 2026 00:00:00 +0000https://devops-monk.com/tutorials/spring-boot/spring-security-jwt/JWT (JSON Web Token) is the standard for stateless REST API authentication. This article builds a complete JWT authentication system — login, token generation, request validation, and token refresh. What is a JWT? A JWT has three base64url-encoded parts separated by dots: eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9 ← Header (algorithm + type) .eyJzdWIiOiJ1c2VyMTIzIiwicm9sZXMiOlsiVVNFUiJdLCJpYXQiOjE3MTQ3MjY0MDAsImV4cCI6MTcxNDczMDAwMH0 ← Payload .SflKxwRJSMeKKF2QT4fwpMeJf36POk6yJV_adQssw5c ← Signature The payload contains claims: { "sub": "user123", // subject (user identifier) "roles": ["USER"], "iat": 1714726400, // issued at "exp": 1714730000 // expires at } The signature is a HMAC of the header+payload — tamper-proof.https://devops-monk.com/2026/05/spring-boot-oauth2-jwt-security/Sun, 03 May 2026 00:00:00 +0000https://devops-monk.com/2026/05/spring-boot-oauth2-jwt-security/Zero-trust API security means every request is validated independently — no session state, no “trusted network” assumptions. A JWT bearer token is issued by an authorisation server, signed cryptographically, and validated on every API call. The API never calls back to the authorisation server during validation; it verifies the token’s signature locally. This guide covers the complete setup: dependencies, resource server configuration, token validation (both symmetric and asymmetric), extracting claims, role-based access control, method-level security, and the Spring Security 7 changes that break existing setups.