NestJS Drizzle CRUD Generator

Overview

This skill automatically generates complete CRUD (Create, Read, Update, Delete) modules for NestJS applications using Drizzle ORM. It creates all necessary files following the zaccheroni-monorepo patterns.

When to Use

• Creating new entity modules with full CRUD endpoints
• Building database-backed features in NestJS
• Generating type-safe DTOs with Zod validation
• Adding services with Drizzle ORM queries
• Creating unit tests with mocked database

Instructions

Step 1: Identify Feature Requirements

Before generating, gather:

• Entity name (e.g., user, product, order)
• List of fields with types
• Required fields vs optional fields

Step 2: Run the Generator

Execute the generation script:

python scripts/generate_crud.py --feature <name> --fields '<json-array>' --output <path>

Step 3: Field Definition Format

Fields must be defined as JSON array with name, type, and required properties.

Step 4: Integrate Module

After generation, integrate the module into your NestJS application.

Examples

Example 1: Generate a User module

python scripts/generate_crud.py \
  --feature user \
  --fields '[{"name": "name", "type": "string", "required": true}, {"name": "email", "type": "string", "required": true}, {"name": "password", "type": "string", "required": true}]' \
  --output ./libs/server

Example 2: Generate a Product module

python scripts/generate_crud.py \
  --feature product \
  --fields '[{"name": "title", "type": "string", "required": true}, {"name": "price", "type": "number", "required": true}, {"name": "description", "type": "text", "required": false}, {"name": "inStock", "type": "boolean", "required": false, "default": true}]' \
  --output ./libs/server

Quick Start

Step 1: Identify Feature Requirements

Before generating, gather:

• Entity name (e.g., user, product, order)
• List of fields with types
• Required fields vs optional fields

Step 2: Run the Generator

Execute the generation script:

python scripts/generate_crud.py --feature <name> --fields '<json-array>' --output <path>

Step 3: Field Definition Format

Fields must be defined as JSON array:

[
  {"name": "name", "type": "string", "required": true},
  {"name": "email", "type": "string", "required": true},
  {"name": "age", "type": "integer", "required": false},
  {"name": "isActive", "type": "boolean", "required": false, "default": true},
  {"name": "price", "type": "number", "required": true},
  {"name": "description", "type": "text", "required": false},
  {"name": "uuid", "type": "uuid", "required": false}
]

Step 4: Example Commands

Generate a User module:

python scripts/generate_crud.py \
  --feature user \
  --fields '[{"name": "name", "type": "string", "required": true}, {"name": "email", "type": "string", "required": true}, {"name": "password", "type": "string", "required": true}]' \
  --output ./libs/server

Generate a Product module:

python scripts/generate_crud.py \
  --feature product \
  --fields '[{"name": "title", "type": "string", "required": true}, {"name": "price", "type": "number", "required": true}, {"name": "description", "type": "text", "required": false}, {"name": "inStock", "type": "boolean", "required": false, "default": true}]' \
  --output ./libs/server

Generated Structure

The generator creates this directory structure:

libs/server/{feature-name}/
├── src/
│   ├── index.ts
│   └── lib/
│       ├── {feature}-feature.module.ts
│       ├── controllers/
│       │   ├── index.ts
│       │   └── {feature}.controller.ts
│       ├── services/
│       │   ├── index.ts
│       │   ├── {feature}.service.ts
│       │   └── {feature}.service.spec.ts
│       ├── dto/
│       │   ├── index.ts
│       │   └── {feature}.dto.ts
│       └── schema/
│           └── {feature}.table.ts

Supported Field Types

Type	Drizzle Column	Zod Schema
string	text	z.string()
text	text	z.string()
number	real	z.number()
integer	integer	z.number().int()
boolean	boolean	z.boolean()
date	timestamp	z.date()
uuid	uuid	z.string().uuid()
email	text	z.string().email()

Features

Module

• Uses forRootAsync pattern for lazy configuration
• Exports generated service for other modules
• Imports DatabaseModule for feature tables

Controller

• Full CRUD endpoints: POST, GET, PATCH, DELETE
• Query parameter validation for pagination
• Zod validation pipe integration

Service

• Drizzle ORM query methods
• Soft delete support (via deletedAt column)
• Pagination with limit/offset
• Filtering support
• Type-safe return types

DTOs

• Zod schemas for Create and Update
• Query parameter schemas for filtering
• NestJS DTO integration

Tests

• Jest test suite
• Mocked Drizzle database
• Test cases for all CRUD operations

Manual Integration

After generation, integrate into your app module:

// app.module.ts
import { {{FeatureName}}FeatureModule } from '@your-org/server-{{feature}}';

@Module({
  imports: [
    {{FeatureName}}FeatureModule.forRootAsync({
      useFactory: () => ({
        defaultPageSize: 10,
        maxPageSize: 100,
      }),
    }),
  ],
})
export class AppModule {}

Field Options

Each field supports:

• name: Field name
• type: Data type (string, text, number, integer, boolean, date, uuid, email)
• required: Boolean for mandatory fields
• default: Default value for non-required fields
• maxLength: Maximum length for strings
• minLength: Minimum length for strings

Dependencies

The generated code requires:

• @nestjs/common
• @nestjs/core
• drizzle-orm
• drizzle-zod
• zod
• nestjs-zod

Best Practices

1. Verify generated code: Always review generated files before committing
2. Run tests: Execute unit tests to verify the generated code works
3. Customize as needed: Add business logic to services after generation
4. Database migrations: Manually create migrations for the generated schema
5. Type safety: Use the generated types in your application code

Constraints and Warnings

• Soft delete only: The generated delete method uses soft delete (sets deletedAt). Hard deletes require manual modification
• No authentication: Generated code does not include auth guards - add them separately
• Basic CRUD only: Complex queries or business logic must be implemented manually
• JSON field escaping: When passing fields JSON on command line, use single quotes around the JSON array