ListBlogs.go

func (s *BlogServiceServer) ListBlogs(req *blogpb.ListBlogsReq, stream blogpb.BlogService_ListBlogsServer) error {
	// Initiate a BlogItem type to write decoded data to
	data := &BlogItem{}
	// collection.Find returns a cursor for our (empty) query
	cursor, err := blogdb.Find(context.Background(), bson.M{})
	if err != nil {
		return status.Errorf(codes.Internal, fmt.Sprintf("Unknown internal error: %v", err))
	}
	// An expression with defer will be called at the end of the function
	defer cursor.Close(context.Background())
	// cursor.Next() returns a boolean, if false there are no more items and loop will break
	for cursor.Next(context.Background()) {
		// Decode the data at the current pointer and write it to data
		err := cursor.Decode(data)
		// check error
		if err != nil {
			return status.Errorf(codes.Unavailable, fmt.Sprintf("Could not decode data: %v", err))
		}
		// If no error is found send blog over stream
		stream.Send(&blogpb.ListBlogsRes{
			Blog: &blogpb.Blog{
				Id:       data.ID.Hex(),
				AuthorId: data.AuthorID,
				Content:  data.Content,
				Title:    data.Title,
			},
		})
	}
	// Check if the cursor has any errors
	if err := cursor.Err(); err != nil {
		return status.Errorf(codes.Internal, fmt.Sprintf("Unkown cursor error: %v", err))
	}
	return nil
}