PMT-14: Implement JWT Auth

build.gradle.kts

@@ -48,6 +48,11 @@ dependencies {
     implementation("org.springframework.boot:spring-boot-starter-data-jpa")
     implementation("org.springframework.boot:spring-boot-starter-validation")
     implementation("org.springframework.boot:spring-boot-starter-web")
+    implementation("org.springframework.boot:spring-boot-starter-security")
+    implementation("org.springframework.boot:spring-boot-starter-oauth2-client")
+    implementation("org.springframework.boot:spring-boot-starter-oauth2-resource-server")
+
+    // Postgres
     runtimeOnly("org.postgresql:postgresql")
 
     // Lombok
@@ -57,6 +62,7 @@ dependencies {
     // Test
     testImplementation("org.springframework.boot:spring-boot-starter-test")
     testImplementation("org.springframework.boot:spring-boot-testcontainers")
+    testImplementation("org.springframework.security:spring-security-test")
     testImplementation("org.testcontainers:junit-jupiter")
     testImplementation("org.testcontainers:postgresql")
     testRuntimeOnly("org.junit.platform:junit-platform-launcher")

src/main/java/de/hmmh/pmt/auth/AuthConfig.java

@@ -0,0 +1,57 @@
+package de.hmmh.pmt.auth;
+
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.security.config.annotation.method.configuration.EnableMethodSecurity;
+import org.springframework.security.config.annotation.web.builders.HttpSecurity;
+import org.springframework.security.config.annotation.web.configuration.EnableWebSecurity;
+import org.springframework.security.core.session.SessionRegistry;
+import org.springframework.security.core.session.SessionRegistryImpl;
+import org.springframework.security.web.SecurityFilterChain;
+import org.springframework.security.web.authentication.session.RegisterSessionAuthenticationStrategy;
+import org.springframework.security.web.authentication.session.SessionAuthenticationStrategy;
+import org.springframework.security.web.session.HttpSessionEventPublisher;
+import org.springframework.security.web.util.matcher.AntPathRequestMatcher;
+
+@Configuration
+@EnableWebSecurity
+@EnableMethodSecurity
+public class AuthConfig {
+
+    private final JWT jwt;
+
+    AuthConfig(JWT jwt) {
+        this.jwt = jwt;
+    }
+
+    @Bean
+    public SessionRegistry sessionRegistry() {
+        return new SessionRegistryImpl();
+    }
+
+    @Bean
+    protected SessionAuthenticationStrategy sessionAuthenticationStrategy() {
+        return new RegisterSessionAuthenticationStrategy(sessionRegistry());
+    }
+
+    @Bean
+    public HttpSessionEventPublisher httpSessionEventPublisher() {
+        return new HttpSessionEventPublisher();
+    }
+
+
+    @Bean
+    public SecurityFilterChain securityFilterChain(HttpSecurity http) throws Exception {
+        http
+                .authorizeHttpRequests(auth -> auth
+                        .anyRequest()
+                        .authenticated()
+                )
+                .oauth2ResourceServer(resourceServer -> resourceServer
+                        .jwt(jwt -> jwt
+                                .jwtAuthenticationConverter(this.jwt.jwtAuthenticationConverter())
+                        )
+                );
+        return http.build();
+    }
+}

src/main/java/de/hmmh/pmt/auth/JWT.java

@@ -0,0 +1,69 @@
+package de.hmmh.pmt.auth;
+
+import jakarta.servlet.http.HttpServletRequest;
+import jakarta.servlet.http.HttpServletResponse;
+import org.springframework.http.ResponseEntity;
+import org.springframework.security.core.Authentication;
+import org.springframework.security.core.GrantedAuthority;
+import org.springframework.security.core.authority.SimpleGrantedAuthority;
+import org.springframework.security.oauth2.core.oidc.user.OidcUser;
+import org.springframework.security.oauth2.server.resource.authentication.JwtAuthenticationConverter;
+import org.springframework.security.web.authentication.logout.LogoutHandler;
+import org.springframework.stereotype.Component;
+import org.springframework.web.client.RestTemplate;
+import org.springframework.web.util.UriComponentsBuilder;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Map;
+
+@Component
+public class JWT implements LogoutHandler {
+    private static final String REALM_ACCESS_CLAIM = "realm_access";
+    private static final String ROLES_CLAIM = "roles";
+    private static final String ROLE_PREFIX = "ROLE_";
+    private static final String OIDC_LOGOUT_ROUTE = "/protocol/openid-connect/logout";
+    private static final String OIDC_TOKEN_HINT_QUERY_PARAMETER = "id_token_hin";
+
+    private final RestTemplate template = new RestTemplate();
+
+    @Override
+    public void logout(HttpServletRequest request, HttpServletResponse response, Authentication authentication) {
+        OidcUser user = (OidcUser) authentication.getPrincipal();
+        String endSessionEndpoint = user.getIssuer() + OIDC_LOGOUT_ROUTE;
+        UriComponentsBuilder builder = UriComponentsBuilder
+                .fromUriString(endSessionEndpoint)
+                .queryParam(OIDC_TOKEN_HINT_QUERY_PARAMETER, user.getIdToken().getTokenValue());
+
+        ResponseEntity<String> logoutResponse = template.getForEntity(builder.toUriString(), String.class);
+        if (logoutResponse.getStatusCode().is2xxSuccessful()) {
+            System.out.println("Logged out successfully");
+        } else {
+            System.out.println("Failed to logout");
+        }
+    }
+
+    public JwtAuthenticationConverter jwtAuthenticationConverter() {
+        JwtAuthenticationConverter jwtAuthenticationConverter = new JwtAuthenticationConverter();
+        jwtAuthenticationConverter.setJwtGrantedAuthoritiesConverter(jwt -> {
+            List<GrantedAuthority> grantedAuthorities = new ArrayList<>();
+
+            Map<String, Object> realmAccess = jwt.getClaim(REALM_ACCESS_CLAIM);
+            if (realmAccess == null || !realmAccess.containsKey(ROLES_CLAIM)) {
+                return grantedAuthorities;
+            }
+
+            Object rolesClaim = realmAccess.get(ROLES_CLAIM);
+            if (!(rolesClaim instanceof List<?>)) {
+                return grantedAuthorities;
+            }
+            for (Object role : (List<?>) rolesClaim) {
+                assert role instanceof String;
+                grantedAuthorities.add(new SimpleGrantedAuthority(ROLE_PREFIX + role));
+            }
+
+            return grantedAuthorities;
+        });
+        return jwtAuthenticationConverter;
+    }
+}

src/main/resources/api.yml

@@ -5,8 +5,15 @@ info:
   version: 1.0.0
 servers:
   - url: /api/v1
+security:
+  - JWTAuth: []
     
 components:
+  securitySchemes:
+    JWTAuth:
+      type: http
+      scheme: bearer
+      bearerFormat: JWT
   schemas: 
     HelloOut:
       description: "A Test Schema"

src/main/resources/application.properties

@@ -6,4 +6,15 @@ server.port=8080
 spring.datasource.url=jdbc:postgresql://localhost:5432/pmt
 spring.datasource.username=pmt_user
 spring.datasource.password=pmt123
-spring.jpa.hibernate.ddl-auto=create-drop
+spring.jpa.hibernate.ddl-auto=create-drop
+
+# JWT Auth
+spring.security.oauth2.client.registration.keycloak.client-id=employee-management-service
+spring.security.oauth2.client.registration.keycloak.authorization-grant-type=authorization_code
+spring.security.oauth2.client.registration.keycloak.scope=openid
+spring.security.oauth2.client.provider.keycloak.issuer-uri=https://keycloak.szut.dev/auth/realms/szut
+spring.security.oauth2.client.provider.keycloak.user-name-attribute=preferred_username
+spring.security.oauth2.resourceserver.jwt.issuer-uri=https://keycloak.szut.dev/auth/realms/szut
+
+# Debugging
+logging.level.org.springframework.security=DEBUG