zod-default-instance

Effortlessly create default instances from Zod schemas with intelligent type inference and flexible customization.

🚀 Features

• 📦 Create default instances from Zod schemas
• 🧠 Intelligent type inference
• 🛠 Support for nested objects, arrays, and complex types
• 🎛 Customizable with partial source objects
• 🔄 Handles discriminated unions and regular unions
• 🏷 Full TypeScript support

📦 Installation

npm install zod-default-instance

or

yarn add zod-default-instance

🛠 Usage

import { z } from 'zod';
import defaultInstance from 'zod-default-instance';

// Define your Zod schema
const userSchema = z.object({
  name: z.string(),
  age: z.number(),
  isActive: z.boolean(),
  roles: z.array(z.string()),
  settings: z.object({
    theme: z.enum(['light', 'dark']),
    notifications: z.boolean()
  })
});

// Create a default instance
const defaultUser = defaultInstance(userSchema);

console.log(defaultUser);
// Output:
// {
//   name: '',
//   age: 0,
//   isActive: false,
//   roles: [],
//   settings: {
//     theme: 'light',
//     notifications: false
//   }
// }

With Partial Source

You can provide a partial source object to override default values:

const partialUser = {
  name: 'John Doe',
  settings: {
    theme: 'dark'
  }
};

const userWithCustomValues = defaultInstance(userSchema, partialUser);

console.log(userWithCustomValues);
// Output:
// {
//   name: 'John Doe',
//   age: 0,
//   isActive: false,
//   roles: [],
//   settings: {
//     theme: 'dark',
//     notifications: false
//   }
// }

🧩 Advanced Usage

Discriminated Unions

const resultSchema = z.discriminatedUnion('status', [
  z.object({ status: z.literal('success'), data: z.string() }),
  z.object({ status: z.literal('error'), message: z.string() })
]);

const defaultResult = defaultInstance(resultSchema);
console.log(defaultResult); // { status: 'success', data: '' }

Regular Unions

const dataSchema = z.union([
  z.object({ type: z.literal('string'), value: z.string() }),
  z.object({ type: z.literal('number'), value: z.number() }),
  z.string()
]);

const defaultData = defaultInstance(dataSchema);
console.log(defaultData); // { type: 'string', value: '' }