feat: provide service to save, overwrite and delete draft messages

src/main/java/de/caritas/cob/messageservice/api/model/draftmessage/SavedDraftType.java

@@ -0,0 +1,20 @@
+package de.caritas.cob.messageservice.api.model.draftmessage;
+
+import org.springframework.http.HttpStatus;
+
+public enum SavedDraftType {
+
+  NEW_MESSAGE(HttpStatus.CREATED),
+  OVERWRITTEN_MESSAGE(HttpStatus.OK);
+
+  private final HttpStatus httpStatus;
+
+  SavedDraftType(HttpStatus httpStatus) {
+    this.httpStatus = httpStatus;
+  }
+
+  public HttpStatus getHttpStatus() {
+    return this.httpStatus;
+  }
+
+}

src/main/java/de/caritas/cob/messageservice/api/model/entity/DraftMessage.java → src/main/java/de/caritas/cob/messageservice/api/model/draftmessage/entity/DraftMessage.java

@@ -1,4 +1,4 @@
-package de.caritas.cob.messageservice.api.model.entity;
+package de.caritas.cob.messageservice.api.model.draftmessage.entity;
 
 import java.time.LocalDateTime;
 import javax.persistence.Column;

src/main/java/de/caritas/cob/messageservice/api/repository/DraftMessageRepository.java

@@ -1,8 +1,11 @@
 package de.caritas.cob.messageservice.api.repository;
 
-import de.caritas.cob.messageservice.api.model.entity.DraftMessage;
+import de.caritas.cob.messageservice.api.model.draftmessage.entity.DraftMessage;
+import java.util.Optional;
 import org.springframework.data.repository.CrudRepository;
 
 public interface DraftMessageRepository extends CrudRepository<DraftMessage, Long> {
 
+  Optional<DraftMessage> findByUserIdAndRcGroupId(String userId, String rcGroupId);
+
 }

src/main/java/de/caritas/cob/messageservice/api/service/DraftMessageService.java

@@ -0,0 +1,84 @@
+package de.caritas.cob.messageservice.api.service;
+
+import static de.caritas.cob.messageservice.api.model.draftmessage.SavedDraftType.NEW_MESSAGE;
+import static de.caritas.cob.messageservice.api.model.draftmessage.SavedDraftType.OVERWRITTEN_MESSAGE;
+
+import de.caritas.cob.messageservice.api.exception.CustomCryptoException;
+import de.caritas.cob.messageservice.api.exception.InternalServerErrorException;
+import de.caritas.cob.messageservice.api.helper.AuthenticatedUser;
+import de.caritas.cob.messageservice.api.model.draftmessage.SavedDraftType;
+import de.caritas.cob.messageservice.api.model.draftmessage.entity.DraftMessage;
+import de.caritas.cob.messageservice.api.repository.DraftMessageRepository;
+import java.time.LocalDateTime;
+import java.util.Optional;
+import lombok.NonNull;
+import lombok.RequiredArgsConstructor;
+import org.springframework.stereotype.Service;
+
+/**
+ * Service class to provide creation, updating and deletion of draft messages.
+ */
+@Service
+@RequiredArgsConstructor
+public class DraftMessageService {
+
+  private final @NonNull DraftMessageRepository draftMessageRepository;
+  private final @NonNull EncryptionService encryptionService;
+  private final @NonNull AuthenticatedUser authenticatedUser;
+
+  /**
+   * Encrypts and saves a draft message. The message will be overwritten if a message for the given
+   * user and rocket chat group id already exists.
+   *
+   * @param message the message to encrypt and persist
+   * @param rcGroupId the rocket chat group id
+   * @return a {@link SavedDraftType} for the created type
+   */
+  public SavedDraftType saveDraftMessage(String message, String rcGroupId) {
+
+    Optional<DraftMessage> optionalDraftMessage = this.draftMessageRepository
+        .findByUserIdAndRcGroupId(this.authenticatedUser.getUserId(), rcGroupId);
+
+    DraftMessage draftMessage = optionalDraftMessage.orElse(buildNewDraftMessage(rcGroupId));
+    updateMessage(message, rcGroupId, draftMessage);
+
+    this.draftMessageRepository.save(draftMessage);
+    return extractSavedDraftType(optionalDraftMessage);
+  }
+
+  private SavedDraftType extractSavedDraftType(Optional<DraftMessage> optionalDraftMessage) {
+    return optionalDraftMessage.isPresent() ? OVERWRITTEN_MESSAGE : NEW_MESSAGE;
+  }
+
+  private DraftMessage buildNewDraftMessage(String rcGroupId) {
+    return DraftMessage.builder()
+        .createDate(LocalDateTime.now())
+        .userId(this.authenticatedUser.getUserId())
+        .rcGroupId(rcGroupId)
+        .build();
+  }
+
+  private void updateMessage(String message, String rcGroupId, DraftMessage draftMessage) {
+    try {
+      String encryptedMessage = this.encryptionService.encrypt(message, rcGroupId);
+      draftMessage.setMessage(encryptedMessage);
+    } catch (CustomCryptoException e) {
+      throw new InternalServerErrorException(e, LogService::logInternalServerError);
+    }
+  }
+
+  /**
+   * Deletes a draft message if exists.
+   *
+   * @param rcGroupId the rocket chat group id
+   */
+  public void deleteDraftMessageIfExist(String rcGroupId) {
+    this.draftMessageRepository.findByUserIdAndRcGroupId(this.authenticatedUser.getUserId(),
+        rcGroupId).ifPresent(this::deleteDraftMessage);
+  }
+
+  private void deleteDraftMessage(DraftMessage draftMessage) {
+    this.draftMessageRepository.delete(draftMessage);
+  }
+
+}

src/test/java/de/caritas/cob/messageservice/api/service/DraftMessageServiceTest.java

@@ -0,0 +1,92 @@
+package de.caritas.cob.messageservice.api.service;
+
+import static de.caritas.cob.messageservice.api.model.draftmessage.SavedDraftType.NEW_MESSAGE;
+import static de.caritas.cob.messageservice.api.model.draftmessage.SavedDraftType.OVERWRITTEN_MESSAGE;
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.is;
+import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.Mockito.times;
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.when;
+
+import de.caritas.cob.messageservice.api.exception.CustomCryptoException;
+import de.caritas.cob.messageservice.api.exception.InternalServerErrorException;
+import de.caritas.cob.messageservice.api.helper.AuthenticatedUser;
+import de.caritas.cob.messageservice.api.model.draftmessage.SavedDraftType;
+import de.caritas.cob.messageservice.api.model.draftmessage.entity.DraftMessage;
+import de.caritas.cob.messageservice.api.repository.DraftMessageRepository;
+import java.util.Optional;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.InjectMocks;
+import org.mockito.Mock;
+import org.mockito.junit.MockitoJUnitRunner;
+
+@RunWith(MockitoJUnitRunner.class)
+public class DraftMessageServiceTest {
+
+  @InjectMocks
+  private DraftMessageService draftMessageService;
+
+  @Mock
+  private DraftMessageRepository draftMessageRepository;
+
+  @Mock
+  private AuthenticatedUser authenticatedUser;
+
+  @Mock
+  private EncryptionService encryptionService;
+
+  @Test
+  public void saveDraftMessage_Should_returnNewMessageType_When_noMessageForUserAndRcGroupExists()
+      throws CustomCryptoException {
+
+    SavedDraftType savedDraftType = this.draftMessageService
+        .saveDraftMessage("message", "rcGroupId");
+
+    assertThat(savedDraftType, is(NEW_MESSAGE));
+    verify(this.draftMessageRepository, times(1)).save(any());
+    verify(this.encryptionService, times(1)).encrypt(any(), any());
+  }
+
+  @Test
+  public void saveDraftMessage_Should_returnOverwrittenMessageType_When_messageForUserAndRcGroupExists()
+      throws CustomCryptoException {
+    when(this.draftMessageRepository.findByUserIdAndRcGroupId(any(), any()))
+        .thenReturn(Optional.of(new DraftMessage()));
+
+    SavedDraftType savedDraftType = this.draftMessageService
+        .saveDraftMessage("message", "rcGroupId");
+
+    assertThat(savedDraftType, is(OVERWRITTEN_MESSAGE));
+    verify(this.draftMessageRepository, times(1)).save(any());
+    verify(this.encryptionService, times(1)).encrypt(any(), any());
+  }
+
+  @Test
+  public void deleteDraftMessageIfExist_Should_notCallDelete_When_noMessageForUserAndGroupExists() {
+    this.draftMessageService.deleteDraftMessageIfExist("rcGroupId");
+
+    verify(this.draftMessageRepository, times(0)).delete(any());
+  }
+
+  @Test
+  public void deleteDraftMessageIfExist_Should_callDelete_When_messageForUserAndGroupExists() {
+    when(this.draftMessageRepository.findByUserIdAndRcGroupId(any(), any()))
+        .thenReturn(Optional.of(new DraftMessage()));
+
+    this.draftMessageService.deleteDraftMessageIfExist("rcGroupId");
+
+    verify(this.draftMessageRepository, times(1)).delete(any());
+  }
+
+  @Test(expected = InternalServerErrorException.class)
+  public void saveDraftMessage_Should_throwInternalServerError_When_encryptionServiceThrowsCustomCryptoException()
+      throws CustomCryptoException {
+    when(this.encryptionService.encrypt(any(), any()))
+        .thenThrow(new CustomCryptoException(new Exception()));
+
+    this.draftMessageService.saveDraftMessage("message", "rcGroupId");
+  }
+
+}