GraphQL to TypeScript Generator

A powerful CLI tool and library to convert GraphQL schemas into TypeScript type definitions.

Features

• 🚀 CLI Tool - Easy to use command-line interface
• 📁 Config File Support - JSON or JS configuration files
• 👀 Watch Mode - Automatically regenerate types on schema changes
• 🎨 Customizable - Custom scalar mappings, prefixes, suffixes
• 📝 Comments - Preserve GraphQL descriptions as TypeScript comments
• 🔧 Flexible Exports - Use as a library in your own tools

Installation

# Global installation
npm install -g graphql-to-ts-generator

# Project dependency
npm install --save-dev graphql-to-ts-generator

Quick Start

# Basic usage
graphql-to-ts schema.graphql

# Specify output file
graphql-to-ts schema.graphql -o types/schema.ts

# Watch mode
graphql-to-ts schema.graphql -w

# With custom options
graphql-to-ts schema.graphql -o types/schema.ts --prefix "GQL" --suffix "Type"

CLI Options

| Option | Description | Default | |--------|-------------|---------| | <input> | Input GraphQL schema file | Required | | -o, --output <path> | Output TypeScript file | types/generated.ts | | -c, --config <path> | Config file path | Auto-detect | | -w, --watch | Watch for file changes | false | | --no-comments | Exclude comments | false | | --prefix <prefix> | Type name prefix | "" | | --suffix <suffix> | Type name suffix | "" | | --enums-as-const | Generate const assertions | false | | --custom-scalars <json> | Custom scalar mappings | {} |

Configuration File

Create a graphql-to-ts.config.json file:

{
  "input": "schema.graphql",
  "output": "types/generated.ts",
  "watch": true,
  "includeComments": true,
  "typePrefix": "GQL",
  "typeSuffix": "Type",
  "enumsAsConst": false,
  "customScalarTypes": {
    "DateTime": "Date",
    "Upload": "File"
  }
}

Or use JavaScript configuration (graphql-to-ts.config.js):

module.exports = {
  input: 'schema.graphql',
  output: 'types/generated.ts',
  customScalarTypes: {
    DateTime: 'Date',
    Upload: 'File'
  }
};

Usage as Library

import { convertGraphQLToTypeScript } from 'graphql-to-ts-generator';

const schema = `
  type User {
    id: ID!
    name: String!
    email: String!
  }
`;

const types = convertGraphQLToTypeScript(schema, {
  customScalarTypes: {
    DateTime: 'Date'
  },
  typePrefix: 'GQL'
});

console.log(types);

Package.json Scripts

Add to your package.json:

{
  "scripts": {
    "generate-types": "graphql-to-ts schema.graphql -o types/generated.ts",
    "generate-types:watch": "graphql-to-ts schema.graphql -o types/generated.ts --watch"
  }
}

Examples

Basic Schema

Input (schema.graphql):

type User {
  id: ID!
  name: String!
  email: String
}

enum Role {
  ADMIN
  USER
}

Output:

export interface User {
  id: string;
  name: string;
  email?: string;
}

export enum Role {
  ADMIN = "ADMIN",
  USER = "USER",
}

With Custom Scalars

graphql-to-ts schema.graphql --custom-scalars '{"DateTime":"Date","JSON":"any"}'

License

MIT

## 10. Publishing Steps

```bash
# Initialize npm package
npm init -y

# Install dependencies
npm install

# Build the package
npm run build

# Test locally
npm link
graphql-to-ts --help

# Publish to npm
npm login
npm publish

11. Example Usage After Publishing

Users can then use your package like this:

# Install globally
npm install -g graphql-to-ts-generator

# Use in any project
graphql-to-ts schema.graphql -o types/generated.ts

# Or as project dependency
npm install --save-dev graphql-to-ts-generator
npx graphql-to-ts schema.graphql

12. Add to package.json scripts

{
  "scripts": {
    "generate-types": "graphql-to-ts schema.graphql -o types/generated.ts",
    "generate-types:watch": "graphql-to-ts schema.graphql -w"
  }
}