Added arch unit tests

pom.xml

@@ -5,7 +5,7 @@
     <parent>
         <groupId>org.springframework.boot</groupId>
         <artifactId>spring-boot-starter-parent</artifactId>
-        <version>4.1.0-SNAPSHOT</version>
+        <version>4.1.0-M4</version>
         <relativePath/> <!-- lookup parent from repository -->
     </parent>
     <groupId>eu.andreasdahm.tbp</groupId>
@@ -15,6 +15,8 @@
     <properties>
         <java.version>25</java.version>
         <jwt.version>0.13.0</jwt.version>
+        <testcontainers.version>1.21.4</testcontainers.version>
+        <archunit.version>1.4.1</archunit.version>
     </properties>
     <dependencies>
         <!-- Spring -->
@@ -128,6 +130,29 @@
             <artifactId>spring-boot-devtools</artifactId>
             <scope>runtime</scope>
         </dependency>
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-testcontainers</artifactId>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.testcontainers</groupId>
+            <artifactId>postgresql</artifactId>
+            <scope>test</scope>
+            <version>${testcontainers.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.testcontainers</groupId>
+            <artifactId>junit-jupiter</artifactId>
+            <version>${testcontainers.version}</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>com.tngtech.archunit</groupId>
+            <artifactId>archunit-junit5</artifactId>
+            <version>${archunit.version}</version>
+            <scope>test</scope>
+        </dependency>
     </dependencies>
 
     <build>

src/main/java/auth_service/configuration/security/JwtService.java

@@ -1,6 +1,5 @@
 package auth_service.configuration.security;
 
-import auth_service.domain.login.model.User;
 import io.jsonwebtoken.Jwts;
 import io.jsonwebtoken.security.Keys;
 import org.springframework.stereotype.Service;
@@ -29,9 +28,9 @@ public class JwtService {
      *
      * @return A signed JWT string
      */
-    public String generateToken(User user) {
+    public String generateToken(String email) {
         return Jwts.builder()
-                .subject(user.getEmail())
+                .subject(email)
                 .issuedAt(new Date(System.currentTimeMillis()))
                 .expiration(new Date(System.currentTimeMillis() + JWT_EXPIRATION_MS))
                 .signWith(getSigningKey())

src/main/java/auth_service/domain/login/controller/LoginController.java

@@ -1,5 +1,6 @@
 package auth_service.domain.login.controller;
 
+import auth_service.configuration.security.JwtService;
 import auth_service.domain.login.controller.dto.request.LoginRequest;
 import auth_service.domain.login.controller.dto.response.LoginResponse;
 import auth_service.domain.login.controller.mapper.ApiMapper;
@@ -21,6 +22,7 @@ import org.springframework.web.bind.annotation.RestController;
 public class LoginController {
 
     private final LoginService loginService;
+    private final JwtService jwtService;
 
     /**
      * Authenticates a user based on email and password.
@@ -33,7 +35,9 @@ public class LoginController {
     public ResponseEntity<LoginResponse> login(@RequestBody LoginRequest request) {
 
         var user = ApiMapper.toModel(request);
-        var jwt = loginService.login(user);
-        return ResponseEntity.ok(new LoginResponse("Login successful", jwt));
+        var authenticatedUser = loginService.login(user);
+        var token = jwtService.generateToken(authenticatedUser.getEmail());
+
+        return ResponseEntity.ok(new LoginResponse("Login successful", token));
     }
 }

src/main/java/auth_service/domain/login/service/LoginService.java

@@ -1,6 +1,5 @@
 package auth_service.domain.login.service;
 
-import auth_service.configuration.security.JwtService;
 import auth_service.domain.login.exception.InvalidCredentialsException;
 import auth_service.domain.login.exception.UserNotFoundException;
 import auth_service.domain.login.model.User;
@@ -16,15 +15,19 @@ import org.springframework.stereotype.Service;
 public class LoginService {
     private final MinimalUserRepository minimalUserRepository;
     private final PasswordEncoder passwordEncoder;
-    private final JwtService jwtService;
 
-    public String login(User userToLogin) {
+    /**
+     * Authenticates a user based on email and raw password.
+     *
+     * @return The authenticated User model
+     */
+    public User login(User userToLogin) {
         var userFromDatabase = minimalUserRepository.findByEmail(userToLogin.getEmail()).orElseThrow(() -> new UserNotFoundException("User not found with given email"));
         var loginSuccessful = passwordEncoder.matches(userToLogin.getPassword(), userFromDatabase.getPassword());
         if (!loginSuccessful) {
             throw new InvalidCredentialsException("Invalid credentials");
         }
 
-        return jwtService.generateToken(userToLogin);
+        return userFromDatabase;
     }
 }

src/test/java/auth_service/AuthServiceApplicationTests.java

@@ -1,15 +1,29 @@
 package auth_service;
 
-import org.junit.jupiter.api.Disabled;
 import org.junit.jupiter.api.Test;
 import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.boot.testcontainers.service.connection.ServiceConnection;
+import org.testcontainers.containers.PostgreSQLContainer;
+import org.testcontainers.junit.jupiter.Container;
+import org.testcontainers.junit.jupiter.Testcontainers;
 
 @SpringBootTest
-@Disabled("Tests temporarily disabled until DB config is ready")
+@Testcontainers
 class AuthServiceApplicationTests {
 
+    /**
+     * Define the PostgreSQL container.
+     *
+     * @ServiceConnection automatically configures the application properties
+     * (URL, username, password) for this specific container.
+     */
+    @Container
+    @ServiceConnection
+    static PostgreSQLContainer<?> postgres = new PostgreSQLContainer<>("postgres:17.9");
+
     @Test
     void contextLoads() {
+        // If the context fails to load (e.g. Flyway migration fails or beans are missing),
+        // this test will fail automatically. No explicit assertions needed.
     }
-
 }

src/test/java/auth_service/architecture/ArchitectureTest.java

@@ -0,0 +1,93 @@
+package auth_service.architecture;
+
+import com.tngtech.archunit.core.importer.ImportOption;
+import com.tngtech.archunit.junit.AnalyzeClasses;
+import com.tngtech.archunit.junit.ArchTest;
+import com.tngtech.archunit.lang.ArchRule;
+import com.tngtech.archunit.library.dependencies.SlicesRuleDefinition;
+
+import static com.tngtech.archunit.lang.syntax.ArchRuleDefinition.classes;
+import static com.tngtech.archunit.lang.syntax.ArchRuleDefinition.noClasses;
+
+/**
+ * ArchUnit tests to enforce Clean Architecture and package boundaries.
+ * Analyzes all classes in the 'auth_service' package, ignoring test classes.
+ */
+@AnalyzeClasses(packages = "auth_service", importOptions = ImportOption.DoNotIncludeTests.class)
+class ArchitectureTest {
+
+    // ===================================================================================
+    // 1. DOMAIN INDEPENDENCE (Slices)
+    // ===================================================================================
+
+    @ArchTest
+    static final ArchRule domains_should_not_depend_on_each_other = SlicesRuleDefinition.slices()
+            .matching("auth_service.domain.(*)..")
+            .should().notDependOnEachOther()
+            .because("Domains (e.g. login, user) should be strictly isolated and independent.");
+
+    // ===================================================================================
+    // 2. CLEAN ARCHITECTURE DEPENDENCY DIRECTION (Inside out)
+    // ===================================================================================
+
+    @ArchTest
+    static final ArchRule domain_core_should_not_depend_on_outside = noClasses()
+            .that().resideInAnyPackage("..model..", "..service..")
+            .should().dependOnClassesThat().resideInAnyPackage("..controller..", "..persistence.entities..", "..persistence.mapper..")
+            .because("Domain core (Models, Services) must not depend on Web/Controller or Persistence details.");
+
+    @ArchTest
+    static final ArchRule persistence_interfaces_belong_to_domain = classes()
+            .that().resideInAPackage("..persistence..")
+            .and().areInterfaces()
+            .should().haveSimpleNameEndingWith("Repository")
+            .because("Repository interfaces are the ports and belong to the domain/persistence boundary.");
+
+    // ===================================================================================
+    // 3. ENCAPSULATION OF DTOs AND ENTITIES
+    // ===================================================================================
+
+    @ArchTest
+    static final ArchRule dtos_should_only_be_used_in_controllers = classes()
+            .that().resideInAPackage("..controller.dto..")
+            .should().onlyBeAccessed().byAnyPackage("..controller..")
+            .because("DTOs are Web/API concerns and must not leak into Services or Persistence.");
+
+    @ArchTest
+    static final ArchRule entities_should_only_be_used_in_persistence = classes()
+            .that().resideInAPackage("..persistence.entities..")
+            .should().onlyBeAccessed().byAnyPackage("..persistence..")
+            .because("Database Entities must not leak into the Domain Core or Controllers.");
+
+    // ===================================================================================
+    // 4. ADDITIONAL BEST PRACTICES
+    // ===================================================================================
+
+    @ArchTest
+    static final ArchRule no_cyclic_dependencies = SlicesRuleDefinition.slices()
+            .matching("auth_service.(*)..")
+            .should().beFreeOfCycles()
+            .because("Cyclic dependencies make the code unmaintainable and tightly coupled.");
+
+    @ArchTest
+    static final ArchRule controllers_should_only_call_services = noClasses()
+            .that().resideInAPackage("..controller..")
+            .should().dependOnClassesThat().resideInAPackage("..persistence..")
+            .because("Controllers must delegate to Services and should not access Persistence directly.");
+
+    @ArchTest
+    static final ArchRule services_should_be_annotated = classes()
+            .that().resideInAPackage("..service..")
+            .and().haveSimpleNameEndingWith("Service")
+            .should().beAnnotatedWith(org.springframework.stereotype.Service.class)
+            .because("Classes named *Service should be registered as Spring @Service beans.");
+
+    @ArchTest
+    static final ArchRule controllers_should_be_annotated = classes()
+            .that().resideInAPackage("..controller..")
+            .and().haveSimpleNameEndingWith("Controller")
+            .should().beAnnotatedWith(org.springframework.web.bind.annotation.RestController.class)
+            .orShould().beAnnotatedWith(org.springframework.web.bind.annotation.ControllerAdvice.class)
+            .orShould().beAnnotatedWith(org.springframework.web.bind.annotation.RestControllerAdvice.class)
+            .because("Classes named *Controller should be registered as Spring @RestController or @ControllerAdvice or @RestControllerAdvice beans.");
+}