Add Service layer

Author: making

todo-api/src/main/java/lol/maki/dev/todo/TodoController.java

@@ -1,102 +1,71 @@
 package lol.maki.dev.todo;
 
 import java.net.URI;
-import java.time.Clock;
-import java.time.Instant;
 import java.util.List;
-import java.util.Objects;
-import java.util.Optional;
-
+import java.util.Map;
 import org.springframework.http.HttpStatus;
 import org.springframework.http.ResponseEntity;
 import org.springframework.security.core.annotation.AuthenticationPrincipal;
 import org.springframework.security.oauth2.jwt.Jwt;
-import org.springframework.util.IdGenerator;
 import org.springframework.web.bind.annotation.DeleteMapping;
+import org.springframework.web.bind.annotation.ExceptionHandler;
 import org.springframework.web.bind.annotation.GetMapping;
 import org.springframework.web.bind.annotation.PatchMapping;
 import org.springframework.web.bind.annotation.PathVariable;
 import org.springframework.web.bind.annotation.PostMapping;
 import org.springframework.web.bind.annotation.RequestBody;
 import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RestController;
-import org.springframework.web.server.ResponseStatusException;
 import org.springframework.web.util.UriComponentsBuilder;
 
 @RestController
 @RequestMapping(path = "/todos")
 public class TodoController {
 
-	private final TodoRepository todoRepository;
-
-	private final IdGenerator idGenerator;
-
-	private final Clock clock;
+	private final TodoService todoService;
 
-	public TodoController(TodoRepository todoRepository, IdGenerator idGenerator, Clock clock) {
-		this.todoRepository = todoRepository;
-		this.idGenerator = idGenerator;
-		this.clock = clock;
+	public TodoController(TodoService todoService) {
+		this.todoService = todoService;
 	}
 
 	@GetMapping(path = "")
 	public ResponseEntity<List<Todo>> getTodos() {
-		List<Todo> todos = this.todoRepository.findAll();
+		List<Todo> todos = this.todoService.getTodos();
 		return ResponseEntity.ok(todos);
 	}
 
 	@GetMapping(path = "/{todoId}")
 	public ResponseEntity<Todo> getTodo(@PathVariable("todoId") String todoId) {
-		Todo todo = this.todoRepository.findById(todoId)
-			.orElseThrow(() -> new ResponseStatusException(HttpStatus.NOT_FOUND,
-					"Todo not found: todoId=%s".formatted(todoId)));
+		Todo todo = this.todoService.getTodo(todoId);
 		return ResponseEntity.ok(todo);
 	}
 
 	@PostMapping(path = "")
 	public ResponseEntity<Todo> postTodos(@RequestBody Todo todo, @AuthenticationPrincipal Jwt jwt,
 			UriComponentsBuilder builder) {
-		Instant now = this.clock.instant();
 		String email = jwt.getClaimAsString("email");
-		Todo initialized = TodoBuilder.from(todo)
-			.todoId(this.idGenerator.generateId().toString())
-			.createdBy(email)
-			.createdAt(now)
-			.updatedBy(email)
-			.updatedAt(now)
-			.build();
-		Todo created = this.todoRepository.save(initialized);
+		Todo created = this.todoService.create(todo.todoTitle(), email);
 		URI uri = builder.pathSegment("todos", created.todoId()).build().toUri();
 		return ResponseEntity.created(uri).body(created);
 	}
 
 	@PatchMapping(path = "/{todoId}")
 	public ResponseEntity<Todo> patchTodo(@PathVariable("todoId") String todoId, @RequestBody Todo todo,
 			@AuthenticationPrincipal Jwt jwt) {
-		Optional<Todo> updated = this.todoRepository.findById(todoId).map(t -> {
-			TodoBuilder builder = TodoBuilder.from(t);
-			boolean touched = false;
-			if (todo.todoTitle() != null) {
-				builder.todoTitle(todo.todoTitle());
-				touched = true;
-			}
-			if (!Objects.equals(todo.finished(), t.finished())) {
-				builder.finished(todo.finished());
-				touched = true;
-			}
-			if (touched) {
-				builder.updatedBy(jwt.getClaimAsString("email"));
-				builder.updatedAt(this.clock.instant());
-			}
-			return builder.build();
-		}).map(this.todoRepository::save);
-		return ResponseEntity.of(updated);
+		String email = jwt.getClaimAsString("email");
+		Todo updated = this.todoService.update(todoId, todo.todoTitle(), todo.finished(), email);
+		return ResponseEntity.ok(updated);
 	}
 
 	@DeleteMapping(path = "/{todoId}")
 	public ResponseEntity<Void> deleteTodo(@PathVariable("todoId") String todoId) {
-		this.todoRepository.deleteById(todoId);
+		this.todoService.deleteById(todoId);
 		return ResponseEntity.noContent().build();
 	}
 
+	@ExceptionHandler(TodoService.NotFoundException.class)
+	public ResponseEntity<?> handleNotFound(TodoService.NotFoundException e) {
+		return ResponseEntity.status(HttpStatus.NOT_FOUND).body(Map.of("message", e.getMessage()));
+	}
+
 }

todo-api/src/main/java/lol/maki/dev/todo/TodoService.java

@@ -0,0 +1,80 @@
+package lol.maki.dev.todo;
+
+import java.time.Clock;
+import java.time.Instant;
+import java.util.List;
+import java.util.Objects;
+import org.springframework.stereotype.Service;
+import org.springframework.util.IdGenerator;
+
+@Service
+public class TodoService {
+
+	private final TodoRepository todoRepository;
+
+	private final IdGenerator idGenerator;
+
+	private final Clock clock;
+
+	public TodoService(TodoRepository todoRepository, IdGenerator idGenerator, Clock clock) {
+		this.todoRepository = todoRepository;
+		this.idGenerator = idGenerator;
+		this.clock = clock;
+	}
+
+	public List<Todo> getTodos() {
+		return this.todoRepository.findAll();
+	}
+
+	public Todo getTodo(String todoId) {
+		return this.todoRepository.findById(todoId).orElseThrow(() -> new NotFoundException(todoId));
+	}
+
+	public Todo create(String todoTitle, String email) {
+		Instant now = this.clock.instant();
+		Todo todo = TodoBuilder.todo()
+			.todoId(this.idGenerator.generateId().toString())
+			.todoTitle(todoTitle)
+			.finished(false)
+			.createdBy(email)
+			.createdAt(now)
+			.updatedBy(email)
+			.updatedAt(now)
+			.build();
+		Todo updated = this.todoRepository.save(todo);
+		return this.todoRepository.save(updated);
+	}
+
+	public Todo update(String todoId, String todoTitle, boolean finished, String email) {
+		return this.todoRepository.findById(todoId).map(t -> {
+			TodoBuilder builder = TodoBuilder.from(t);
+			boolean touched = false;
+			if (todoTitle != null) {
+				builder.todoTitle(todoTitle);
+				touched = true;
+			}
+			if (!Objects.equals(finished, t.finished())) {
+				builder.finished(finished);
+				touched = true;
+			}
+			if (touched) {
+				builder.updatedBy(email);
+				builder.updatedAt(this.clock.instant());
+			}
+			return builder.build();
+		}).map(this.todoRepository::save).orElseThrow(() -> new NotFoundException(todoId));
+	}
+
+	public void deleteById(String todoId) {
+		this.todoRepository.deleteById(todoId);
+	}
+
+	public static class NotFoundException extends RuntimeException {
+
+		public NotFoundException(String todoId) {
+			super("Todo not found: todoId=%s".formatted(todoId));
+		}
+
+	}
+
+}