What should I use as validation tool using NestJS and MongoDB?-CodePudding

Let's say, I am creating application using NestJS. I use MongoDB as a database and mongoose as ODM. So, NestJS has it's own way to validate data - ValidationPipe's. On the other side, there is mongoose built-in ways to validate data that being pushed into DB. The question is - can I use only NestJS validation or do I need also second-check my data using mongoose validation tools?

Personally, I can't see why should I use additional layer of validation if I already have NestJS validation. But maybe there is best-practice or something?

CodePudding user response：

Each database validates input data and emits an error if found. However, you must take into account your schema file. For instance, if you are using Prisma(It doesn't actually matter) and you have a User model like below

model User {
  id            String          @id @default(auto()) @map("_id") @db.ObjectId
  email         String          @unique
  password      String
  name          String
  image         String?
  createdAt     DateTime        @default(now())
  updatedAt     DateTime        @updatedAt
  
  @@map("user")
}

As you can see there is only one optional property "image". Whether you pass a value for image property or not, the database will insert the data as a row. On the other hand, the properties without "?" mark at the end of the type, will not be stored if you don't pass them and emit an error.

Therefore, if you modeled schema according to your business logic, you don't need to validate twice but only add an exception handling like the one below.

const user = await this.usersService.findOne('id...')
                   .catch((e) => new NotFoundException({ message: 'No user found.' }))