Learn MICRONAUT-SECURITY with Real Code Examples

Micronaut Security integrates seamlessly with Micronaut applications to provide JWT, OAuth2, LDAP, and custom authentication strategies.

Supports role-based and attribute-based access control for granular authorization.

Reactive and non-blocking, designed for high-performance microservices.

Simplifies secure API development with declarative annotations and configuration.

Extensible to integrate with external identity providers and custom authentication mechanisms.

Authentication mechanisms (JWT, OAuth2, LDAP, custom)

Authorization via annotations (@Secured, @RolesAllowed)

Method-level and endpoint-level security

Integration with reactive and non-reactive applications

Security filters and token validation

Authentication - verifying user identity (JWT, OAuth2, LDAP)

Authorization - determining access rights (roles, permissions)

Controller - endpoints secured with annotations

Filter - intercept requests for security processing

Token - JWT or OAuth2 access token for stateless security

src/main/java - application code

src/main/resources/application.yml - security configuration

controllers/ - endpoint definitions

services/ - user authentication and role logic

security/ - custom authentication providers or filters

Enable security feature in Micronaut project

Configure authentication provider (JWT, OAuth2, LDAP)

Annotate controllers or methods with `@Secured` or `@RolesAllowed`

Implement custom user details or token validation if needed

Test secured endpoints with appropriate credentials or tokens

Beginner: secure a single REST endpoint with JWT

Intermediate: role-based access control for multiple controllers

Advanced: OAuth2 integration with external identity provider

Expert: custom reactive security filters and token validation

Enterprise: multi-service security architecture with SSO

Micronaut Security vs Spring Security: Micronaut reactive, lightweight, compile-time; Spring Security richer ecosystem, runtime reflection

Micronaut Security vs Keycloak standalone: Keycloak full-featured IdP, Micronaut integrates IdP into services

Micronaut Security vs OAuth2 libraries: Micronaut provides framework integration and annotations

Micronaut Security vs Quarkus Security: both reactive, compile-time; Micronaut favors JVM microservices

Micronaut Security vs Express middleware: Micronaut offers declarative, typed Java/Kotlin security

2018 - Initial Micronaut Security modules introduced

2019 - JWT and OAuth2 support added

2020 - Reactive security features stabilized

2022 - LDAP and multi-provider support expanded

2025 - Latest stable version with full reactive microservices support

Authentication - verifying identity

Authorization - checking access permissions

JWT - JSON Web Token for stateless authentication

OAuth2 - protocol for delegated access

Secured annotation - declares security requirements