fix

src/app.controller.ts

@@ -2,7 +2,7 @@ import { BadRequestException, Body, Controller, Get, Post } from '@nestjs/common
 import { AppService } from './app.service';
 import * as fs from 'fs';
 import { ApiProperty } from '@nestjs/swagger';
-import { IsArray, IsBoolean, IsDate, IsDateString, IsNotEmpty, IsString } from 'class-validator';
+import { IsArray, IsBoolean, IsDateString, IsNotEmpty, IsString } from 'class-validator';
 import { NodeVisitorEntity } from './node-visitor.entity';
 import { DataSource } from 'typeorm';
 import * as bluebird from 'bluebird';