@redis-nest/db-validator

Database validation decorators for NestJS with TypeORM. This library provides custom validators to check for uniqueness and existence of values in your database.

Installation

npm install @redis-nest/db-validator

Peer Dependencies

This library requires the following peer dependencies (already installed in your NestJS project):

• @nestjs/common (^10.0.0 || ^11.0.0)
• @nestjs/typeorm (^10.0.0 || ^11.0.0)
• class-validator (^0.14.0)
• typeorm (^0.3.0)

Setup

1. Import the ValidatorsModule in your AppModule

import { Module } from '@nestjs/common';
import { ValidatorsModule } from '@redis-nest/db-validator';

@Module({
  imports: [
    // ... other modules
    ValidatorsModule,
  ],
})
export class AppModule {}

2. Use the validators in your DTOs

import { UniqueDB, IsExists } from '@redis-nest/db-validator';
import { User } from '../entities/user.entity';
import { Role } from '../entities/role.entity';

export class CreateUserDto {
  @UniqueDB(User, 'email', { message: 'Email already exists' })
  @IsEmail()
  @IsNotEmpty()
  email: string;
}

export class UpdateUserDto {
  @IsExists(Role, 'id', { message: 'Role does not exist' })
  @IsNotEmpty()
  roleId: number;
}

Validators

@UniqueDB(entity, fieldName, options?)

Validates that a field value is unique in the database.

Parameters:

• entity: The TypeORM entity class
• fieldName: The field name to check for uniqueness
• options: Optional validation options (e.g., { message: 'Custom error message' })

Example:

@UniqueDB(User, 'email')
email: string;

@IsExists(entity, fieldName, options?)

Validates that a field value exists in the database.

Parameters:

• entity: The TypeORM entity class
• fieldName: The field name to check for existence
• options: Optional validation options (e.g., { message: 'Custom error message' })

Example:

@IsExists(Role, 'id')
roleId: number;

How It Works

1. The ValidatorsModule registers a ValidationService that uses TypeORM's DataSource to query the database.
2. The validators use this service to check for uniqueness or existence.
3. If the service is not available, the validators fall back to using getRepository() directly.

License

MIT