ts-schema-factory/README.md

Generate TypeScript interfaces from database query results or JS arrays

# ts-schema-factory

Generate TypeScript interfaces from database query results or JavaScript arrays automatically.

## Installation

```bash
npm install ts-schema-factory
```

## Usage

### From JavaScript Array

```javascript
const { generateInterfaceFromArray } = require('ts-schema-factory');

const rows = [
  { id: 1, name: 'Alice', age: 30 },
  { id: 2, name: 'Bob', age: null },
  { id: 3, name: 'Charlie', active: true, notes: 'Hello' }
];

// Generate TypeScript interface and save to User.ts
const tsInterface = generateInterfaceFromArray(rows, 'User', 'User.ts');

// Print interface to console
console.log(tsInterface);
```

### Output

```typescript
interface User {
  id: number;
  name: string;
  age?: number | null;
  active?: boolean | null;
  notes?: string | null;
}
```

### Optional: Save to File

Pass the third argument as a filename, e.g., `'User.ts'`. The interface will be written to that file automatically.

## API

### `generateInterfaceFromArray(dataArray, interfaceName, outputFile?)`

* **dataArray**: Array of objects (like database query results)
* **interfaceName**: Name of the TypeScript interface to generate
* **outputFile** *(optional)*: Path to save the interface as a `.ts` file
* **Returns**: The generated TypeScript interface as a string

## Example

```javascript
const { generateInterfaceFromArray } = require('ts-schema-factory');

const data = [
  { id: 1, title: 'Book 1', price: 9.99 },
  { id: 2, title: 'Book 2', price: 12.5, description: 'A great book' }
];

generateInterfaceFromArray(data, 'Book', 'Book.ts');
```

This will create a file `Book.ts` with:

```typescript
interface Book {
  id: number;
  title: string;
  price: number;
  description?: string | null;
}
```

## License

MIT