io.grpc.stub.StreamObserver#onValue ( )源码实例Demo

@Override
public final void signIn(final SignInRequest request,
                         final StreamObserver<SignInResponse> responseObserver) {

  SignInResponse reply;
  try {
    GitkitUser gitkitUser = AuthUtils.verifyGitkitToken(request.getGitkitToken());
    reply = SignInResponse.newBuilder().setUserToken(AuthUtils.getJwt(gitkitUser.getLocalId()))
        .build();
  } catch (GitkitClientException | IOException | SignatureException | InvalidKeyException e) {
    LOGGER.warning("Authentication error with Gitkit Client " + e.getMessage());
    reply = SignInResponse.newBuilder().setError(getErrorMessage("500", e.getMessage())).build();
  }
  responseObserver.onValue(reply);
  responseObserver.onCompleted();
}
 

@Override
public final void ratePhoto(final VoteRequest request,
                            final StreamObserver<StatusResponse> responseObserver) {
  StatusResponse reply;
  if (AuthUtils.isSignedIn()) {
    long photoId = request.getPhotoId();
    try {
      Entity photo = dbClient.getPhoto(photoId);
      // Let's rate the photo
      int vote = 0;
      if (request.getVote() == VoteRequest.VoteType.THUMBS_DOWN) {
        vote = -1;
      } else if (request.getVote() == VoteRequest.VoteType.THUMBS_UP) {
        vote = 1;
      }
      if (photo != null && dbClient.voteForPhoto(photoId, vote, AuthUtils.getUserId())) {
        // Everything went well
        reply = StatusResponse.newBuilder().build();
      } else if (photo == null) {
        // Photo does not exist
        reply = StatusResponse.newBuilder().setError(getErrorMessage("404", "Photo not found"))
            .build();
      } else {
        // Internal error, impossible to rate
        reply = StatusResponse.newBuilder().setError(getDbErrorMessage()).build();
      }
    }  catch (DatastoreException e) {
      // Internal error
      reply = StatusResponse.newBuilder().setError(getDbErrorMessage()).build();
    }
  } else {
    reply = StatusResponse.newBuilder().setError(getAuthErrorMessage()).build();
  }
  responseObserver.onValue(reply);
  responseObserver.onCompleted();
}
 

/**
 * Lists photos for listMyPhotos, listMyLikes.
 * @param request the gRPC request
 * @param responseObserver the gRPC response observer that will send the response to the client
 * @param listKind the kind of list we want to return from dbClient.PhotoListType
 */
public final void listPhotos(final PhotoListRequest request,
                             final StreamObserver<PhotoListResponse> responseObserver,
                             final DbClient.PhotoListType listKind) {
  PhotoListResponse reply;
  if (AuthUtils.isSignedIn()) {
    long page = request.getPageNumber();
    DbClient.EntityListAndCursorResult photoListAndCursor;
    try {
      ByteString cursor = null;
      boolean pageError = false;
      if (page != 0) {
        Entity cursorEntity = dbClient.getAndDeleteCursor(page);
        if (cursorEntity != null) {
          cursor = getByteString(getPropertyMap(cursorEntity).get("cursor"));
        } else {
          pageError = true;
        }
      }
      photoListAndCursor = dbClient.getPhotoList(AuthUtils.getUserId(), listKind, cursor);

      PhotoListResponse.Builder builder = PhotoListResponse.newBuilder();
      if (pageError) {
        // Invalid cursor, send an error but also return results
        builder.setError(getErrorMessage("400-200",
            "Invalid page, returning results from scratch"));
      }
      for (Entity result : photoListAndCursor.getEntityList()) {
        Map<String, Value> props = getPropertyMap(result);
        long rating = 1;
        if (listKind == DbClient.PhotoListType.PHOTO_LIST_STREAM) {
          rating = dbClient.getVoteValueForPhoto(DbUtils.getEntityId(result),
              getString(props.get("userId")));
        }
        Photo photo = Photo.newBuilder()
            .setPhotoId(DbUtils.getEntityId(result))
            .setUserId(getString(props.get("userId")))
            .setDate(getTimestamp(props.get("date")))
            .setDescription(getString(props.get("description")))
            .setRating(rating)
            .setUrl(BackendConstants.IMAGES_BASE_URL + DbUtils.getEntityId(result) + "_"
                + getString(props.get("userId")) + ".webp")
            .build();

        builder.addPhoto(photo);
      }
      if (photoListAndCursor.getCursor() != null
          && photoListAndCursor.getEntityList().size() > 0) {
        long cursorId = dbClient.insertCursor(photoListAndCursor.getCursor(),
            AuthUtils.getUserId());
        builder.setNextPage(cursorId);
      }
      // Everything went well
      reply = builder.build();

    } catch (DatastoreException e) {
      // Internal error, impossible to list the photos
      reply = PhotoListResponse.newBuilder().setError(getDbErrorMessage()).build();
    }
  } else {
    reply = PhotoListResponse.newBuilder().setError(getAuthErrorMessage()).build();
  }
  responseObserver.onValue(reply);
  responseObserver.onCompleted();
}
 

@Override
public final void flagPhoto(final FlagRequest request,
                            final StreamObserver<StatusResponse> responseObserver) {
  StatusResponse reply;
  if (AuthUtils.isSignedIn()) {
    long photoId = request.getPhotoId();
    try {
      Entity photo = dbClient.getPhoto(photoId);
      if (photo == null) {
        throw new DatastoreException("flagPhoto", 404, "Photo not found in Database", null);
      }
      List<Entity> photoFlags = dbClient.getPhotoFlags(photo.getKey());

      boolean hasAlreadyFlagged = false;
      for (Entity flag : photoFlags) {
        Map<String, Value> propsFlag = getPropertyMap(flag);
        String userIdFlag = propsFlag.get("userId").getStringValue();
        if (userIdFlag != null && userIdFlag.equals(AuthUtils.getUserId())) {
          hasAlreadyFlagged = true;
        }
      }
      if (!hasAlreadyFlagged) {
        if (dbClient.insertFlag(photo.getKey(), AuthUtils.getUserId())) {
          if (photoFlags.size() + 1 >= 2 && !dbClient.setPhotoFlagged(photo.getKey())) {
            // Internal error, impossible to flag the photo
            // Let's not say anything to the user as he did
            // his job.
            LOGGER.warning("Impossible to flag photo=" + photoId + " with count_flags="
                + photoFlags.size());
          }
          // Everything went well
          reply = StatusResponse.newBuilder().build();
        } else {
          // Internal error, impossible to store the flag
          reply = StatusResponse.newBuilder().setError(getDbErrorMessage()).build();
        }
      } else {
        // User has already flagged the picture, do nothing
        reply = StatusResponse.newBuilder().build();
      }
    } catch (DatastoreException e) {
      // Internal error, impossible to store the flag
      reply = StatusResponse.newBuilder().setError(getDbErrorMessage()).build();
    }
  } else {
    reply = StatusResponse.newBuilder().setError(getAuthErrorMessage()).build();
  }
  responseObserver.onValue(reply);
  responseObserver.onCompleted();
}
 

@Override
public final void editPhoto(final EditPhotoRequest request,
                            final StreamObserver<StatusResponse> responseObserver) {
  StatusResponse reply;
  if (AuthUtils.isSignedIn()) {
    long photoId = request.getPhotoId();
    Entity photo;
    try {
      photo = dbClient.getPhoto(photoId);
      if (photo == null) {
        throw new DatastoreException("editPhoto", 404, "Photo not found in Database", null);
      }
      Map<String, Value> propsPhoto = getPropertyMap(photo);
      String userIdPhoto = propsPhoto.get("userId").getStringValue();
      if (userIdPhoto != null) {
        if (userIdPhoto.equals(AuthUtils.getUserId())) {
          // Let's update the photo
          if (dbClient.updatePhotoDescription(photo.getKey(), request.getDescription())) {
            // Everything went well
            reply = StatusResponse.newBuilder().build();
          } else {
            // Internal error, impossible to delete
            reply = StatusResponse.newBuilder().setError(getDbErrorMessage()).build();
          }
        } else {
          // The user is trying to edit a photo that he does not
          // own
          reply = StatusResponse.newBuilder().setError(getErrorMessage("403",
                  "Not the owner of the photo")).build();
        }
      } else {
        // Internal error - no property userId on the photo
        reply = StatusResponse.newBuilder().setError(getDbErrorMessage()).build();
      }
    }  catch (DatastoreException e) {
      // Internal error
      reply = StatusResponse.newBuilder().setError(getDbErrorMessage()).build();
    }
  } else {
    reply = StatusResponse.newBuilder().setError(getAuthErrorMessage()).build();
  }
  responseObserver.onValue(reply);
  responseObserver.onCompleted();
}
 

@Override
public final void deletePhoto(final DeletePhotoRequest request,
                              final StreamObserver<StatusResponse> responseObserver) {
  StatusResponse reply;
  if (AuthUtils.isSignedIn()) {
    long photoId = request.getPhotoId();
    try {
      Entity photo = dbClient.getPhoto(photoId);
      if (photo == null) {
        throw new DatastoreException("deletePhoto", 404, "Photo not found in Database", null);
      }
      Map<String, Value> propsPhoto = getPropertyMap(photo);
      String userIdPhoto = propsPhoto.get("userId").getStringValue();
      if (userIdPhoto != null) {
        if (userIdPhoto.equals(AuthUtils.getUserId())) {
          // Let's delete all the data associated to this photo
          if (dbClient.deletePhotoAndChildren(photo.getKey())) {
            // Everything went well
            reply = StatusResponse.newBuilder().build();
          } else {
            // Internal error, impossible to delete
            reply = StatusResponse.newBuilder().setError(getDbErrorMessage()).build();
          }
        } else {
          // The user is trying to suppress a photo that he
          // does not own
          reply = StatusResponse.newBuilder().setError(getErrorMessage("403",
                  "Not the owner of the photo")).build();
        }
      } else {
        // Internal error - no property userId on the photo
        reply = StatusResponse.newBuilder().setError(getDbErrorMessage()).build();
      }
    }  catch (DatastoreException e) {
      // Internal error
      reply = StatusResponse.newBuilder().setError(getDbErrorMessage()).build();
    }
  } else {
    reply = StatusResponse.newBuilder().setError(getAuthErrorMessage()).build();
  }
  responseObserver.onValue(reply);
  responseObserver.onCompleted();
}