@saas-power-factory/response-kit

Tiny Express helper to send consistent API responses with configurable required keys and default envelopes.

Quick Start

import express from 'express'
import { sendResponse, defaultMiddleware } from '@saas-power-factory/response-kit'

const app = express()
app.use(express.json())

// Option 1: Direct helper (no middleware needed)
app.get('/simple', (req, res) => {
  sendResponse(res, { status: 200, message: 'ok', data: { hello: 'world' } })
})

// Option 2: Use middleware to attach res.api.send
app.use(defaultMiddleware)
app.get('/middleware', (req, res) => {
  res.api.send({ status: 200, message: 'ok', data: { hello: 'world' } })
})

Configurable Response Kit

Create a configured response helper that ensures required keys are always present:

import { createResponseKit } from '@saas-power-factory/response-kit'

const { sendResponse, middleware } = createResponseKit({
  requiredKeys: ['status', 'message', 'error'],
  defaultEnvelope: { message: 'default message' },
  defaultStatus: 200
})

app.use(middleware)

app.get('/api/data', (req, res) => {
  // Only provide data - required keys will be filled automatically
  res.api.send({ data: { items: [] } })
  // Result: { status: 200, message: 'default message', error: null, data: { items: [] } }
})

app.get('/api/replace', (req, res) => {
  // Replace mode: custom payload replaces defaults but required keys are ensured
  sendResponse(res, { status: 201, custom: 'field' }, { replace: true })
  // Result: { status: 201, message: null, error: null, custom: 'field' }
})

Features

• Consistent shape: All responses follow the same JSON structure
• Required keys: Ensure specific fields are always present
• Default values: Set fallback values for common fields
• Replace mode: Option to override default envelope completely
• TypeScript friendly: Proper types, no as any needed
• Flexible: Accept custom fields alongside standard ones