FauxAPI

A schema-based mock JSON generator with CLI and API mocking capabilities.

Features

• 🎯 Schema-driven mock data generation
• 🔄 Deterministic output with seed support
• 🖥️ Powerful CLI tool
• 🌐 Mock API server (coming soon)
• 📦 TypeScript-first with full type inference
• 🚀 ESM and CommonJS support

Installation

npm install -g fauxapi

Usage

Programmatic API

import { defineMock, generate, string, number, email } from 'fauxapi';

const userSchema = defineMock({
  id: number(),
  name: string(),
  email: email(),
});

const user = generate(userSchema);
// { id: 42, name: "lorem", email: "[email protected]" }

const users = generate(userSchema, { count: 5, seed: 123 });
// Array of 5 users with deterministic data

CLI

Generate from a schema file:

fauxapi generate path/to/schema.js
fauxapi generate path/to/schema.mjs
fauxapi generate path/to/schema.json
fauxapi generate path/to/schema.ts  # requires esbuild installed

Example schema.mjs:

import { defineMock, string, number, email } from './dist/index.js';

export default defineMock({
  id: number,
  name: string,
  email: email,
});

Generate and print one object:

fauxapi generate ./schema.mjs

Generate five deterministic objects:

fauxapi generate ./schema.mjs --count 5 --seed 42

Options:

• -o, --out <file>: Output to file
• -c, --count <number>: Number objects (default: 1)
• -s, --seed <number>: Seed for deterministic data

Built-in Generators

• string(): Random string
• number(): Random number
• boolean(): Random boolean
• email(): Random email
• uuid(): Random UUID
• date(): Random ISO date string

Nested schema support

generate now supports nested object schemas and nested arrays within schema values.

import { defineMock, generate, string, number, boolean } from 'fauxapi';

const schema = defineMock({
  user: {
    name: string,
    age: number,
  },
  settings: {
    theme: 'dark',
    notifications: boolean,
  },
});

const result = generate(schema);
// {
//   user: { name: '...', age: ... },
//   settings: { theme: 'dark', notifications: true }
// }

Nested arrays are also supported in schema values:

const schemaWithList = defineMock({
  tags: ['a', 'b', 'c'],
  entries: [
    { id: number, value: string },
  ],
});

Custom Generators

const schema = defineMock({
  custom: () => 'always this value',
  fakerName: () => faker.person.fullName(),
});

API

defineMock(schema)

Defines a mock schema.

generate(schema, options?)

Generates mock data from schema.

Options:

• seed?: number - Seed for deterministic output
• count?: number - Number of items to generate (returns array if > 1)

Development

npm install
npm run build
npm test

License

MIT