prisma-class-dto-generator

prisma-class-dto-generator

A generator for Prisma ORM that creates fully-typed Data Transfer Objects (DTOs) based on decorators from class-validator and class-transformer. It also provides a custom @Entity decorator for enhanced type support, enabling correct JSON schema generation. The resulting DTOs are ready for server-side TypeScript applications, and are well-suited for use with frameworks like routing-controllers, routing-controllers-openapi, and class-validator-jsonschema.

Author: unbywyd
License: Free

---

Features

• Automated DTO Generation: For each Prisma model, generates corresponding input and output DTO classes. For example, a model App will produce InputAppDTO and OutputAppDTO.
• List Types: Supports generating list DTOs for batch queries, including:
  • Pagination
  • Filters
  • Sorting
  • Flexible array elements (i.e., specifying which models the array should contain)
• Enum Generation: Handles generation of enums from the Prisma schema.
• Custom Models & Enums: Ability to create arbitrary custom models and enums via configuration.
• Fine-Grained Control via Schema Comments:
  Decorators like @filterable, @exclude input|output, @listable, and @orderable let you control which fields appear in inputs, outputs, filters, and sorting.
• Selective Generation: Choose exactly which models to generate, which fields to include or exclude, and how they should be extended.
• Integration with Class-Validator-JsonSchema & Routing-Controllers-OpenAPI:
  Easily generate OpenAPI specs and JSON schemas from your DTOs.
  Example:

  @OpenAPI({
    summary: "Get incoming requests",
    description: "Get incoming requests",
    responses: getOpenAPIResponse(OutputRequestDTO, true)
  })
  

• Lazy Imports for Deep Type Integration:

@Entity(() => import('./ExtraAppDTO.model').then(m => m.ExtraAppDTO), true)
items: ExtraAppDTO[];

Installation

npm install prisma-class-dto-generator

Usage

Just add the generator to your schema.prisma file:

generator class_validator {
  provider   = "node node_modules/prisma-class-dto-generator"
  output     = "../src/dto_sources"
  configPath = "./"
}

Configuration

Create a generator-config.json file next to your Prisma schema file (e.g. schema.prisma). This JSON file allows you to specify input/output configurations, excluded fields, included relations, extended models, list configurations, and more.

TYPE: GeneratorConfig

export type PrismaClassDTOGeneratorModelConfig = {
  excludeFields?: string[];
  excludeModels?: string[];
  excludeModelFields?: {
    [modelName: string]: string[]
  };
  includeModelFields?: {
    [modelName: string]: string[]
  };
  includeRelations?: boolean;
  extendModels?: {
    [modelName: string]: {
      fields: Array<PrismaClassDTOGeneratorField>
    }
  }
};
export type PrismaClassDTOGeneratorListModelConfig = {
  pagination?: true,
  itemsModePrefix?: string,
  filters?: Array<string | PrismaClassDTOGeneratorField>,
  orderable?: boolean
};
export type PrismaClassDTOGeneratorConfig = {
  input: PrismaClassDTOGeneratorModelConfig;
  output: PrismaClassDTOGeneratorModelConfig;
  excludeModels?: string[];
  list?: { // Generate list DTOs
    includeModels: {
      [modelName: string]: PrismaClassDTOGeneratorListModelConfig
    }
  },
  extra?: { // Additional models and enums
    enums?: {
      [enumName: string]: {
        values: Array<string>
      }
    },
    models: {
      [modelName: string]: {
        type: "input" | "output",
        fields: Array<PrismaClassDTOGeneratorField>
      }
    }
  }
};

Example generator-config.json:

{
  "excludeModels": [],
  "input": {
    "excludeFields": ["id", "createdAt", "updatedAt"],
    "includeRelations": true,
    "includeModelFields": {
      "App": ["name", "description", "test"]
    }
  },
  "output": {
    "excludeFields": [],
    "includeRelations": true,
    "excludeModelFields": {
      "App": []
    },
    "includeModelFields": {},
    "extendModels": {
      "App": {
        "fields": [
          {
            "name": "role",
            "type": "ERole",
            "isExtra": true,
            "kind": "enum",
            "isRequired": false
          }
        ]
      }
    }
  },
  "list": {
    "includeModels": {
      "App": {
        "pagination": true,
        "orderable": true,
        "itemsModePrefix": "Extra",
        "filters": [
          {
            "name": "test_best",
            "type": "String",
            "isList": true
          }
        ]
      }
    }
  },
  "extra": {
    "enums": {
      "ERole": {
        "values": ["ADMIN", "USER"]
      }
    },
    "models": {
      "App": {
        "fields": [
          { "name": "test", "type": "String", "isRequired": true },
          { "name": "description", "type": "String", "isRequired": true },
          { "name": "role", "type": "Role", "kind": "enum", "isRequired": true }
        ]
      },
      "Best": {
        "fields": [
          { "name": "app", "type": "App", "relationName": "app", "isRequired": true },
          { "name": "paidAt", "type": "DateTime", "isRequired": true },
          { "name": "gena", "type": "Gena", "relationName": "gena", "isRequired": true }
        ]
      }
    }
  }
}

Comment-Based Configuration within Prisma Schema:

model App {
  id          String   @id @default(cuid())
  name        String   @unique /// @filterable
  description String?  /// @exclude output
  logoUrl     String?
  isActive    Boolean  @default(true)
  apiKey      String   @unique @default(cuid())
  createdAt   DateTime @default(now())
  updatedAt   DateTime @updatedAt /// @filterable
  email       String   @unique /// @filterable
  password    String   /// @exclude input
  isConfirmed Boolean  @default(false)
  test        Test[]
  /// @listable
  /// @orderable
}

Details

Note on extendModels

The extendModels option in the configuration allows you to either add new fields or update existing fields in the DTOs:

Adding new fields: If a field specified in extendModels does not exist in the original model, it will be added as a new field. Updating existing fields: If a field with the same name already exists, its properties (e.g., isRequired) will be overridden with the values from extendModels. Example Given the following configuration:

{
  "input": {
    "extendModels": {
      "Item": {
        "fields": [
          {
            "name": "title",
            "isRequired": false
          }
        ]
      }
    }
  }
}

• If the Item model already has a title field, its isRequired property will be updated to false.
• If the title field does not exist in the Item model, it will be added as a new optional field.

Supported Comments:

• @filterable: Enables filtering for this field in list queries.
• @exclude {type} output|input: Exclude a field from either the output or input DTO.
• @listable: Makes the entire model listable.
• @orderable: Enables sorting capabilities.
• @pagination: Enables pagination capabilities.

Helper ToDTO

Utility functions like toDTO help you transform plain data to DTO instances with class-transformer:

import { plainToClass } from "class-transformer";

export function toDTO<T>(DtoClass: new (...args: any[]) => T, data: any): T {
  return plainToClass(DtoClass, data, {
    excludeExtraneousValues: true,
  });
}

Author

unbywyd