api-helper-lib

Full-stack API helpers: query parsing, headers, body parsing, response builders, and HTTP status utilities. Use in Node (Express, Fastify, etc.) or with fetch/Workers.

Features

• Zero dependencies
• Query — Parse and stringify URL query strings
• Headers — Read Authorization/Bearer, Content-Type, CORS helpers
• Body — Parse JSON or form body from Request / IncomingMessage
• Response — Consistent JSON success/error and paginated responses
• Status — HTTP status constants and helpers

Installation

npm install api-helper-lib

Quick Start

const {
  parseQuery,
  getQueryParam,
  getBearerToken,
  parseBody,
  successResponse,
  errorResponse,
  STATUS,
  corsHeaders,
} = require('api-helper-lib');

// Query (e.g. req.url or location.search)
const params = parseQuery('?page=1&sort=name');
const page = getQueryParam(req.url, 'page');

// Headers
const token = getBearerToken(req.headers);
const cors = corsHeaders('*', { credentials: true });

// Body (async)
const data = await parseBody(req, req.headers);

// Response shapes (use with your framework)
const res = successResponse({ user: { id: 1 } });
const err = errorResponse('Invalid input', STATUS.BAD_REQUEST);
const notFound = notFoundResponse();
const validation = validationErrorResponse([{ field: 'email', message: 'Invalid' }]);

Subpath Imports

const query = require('api-helper-lib/query');
const headers = require('api-helper-lib/headers');
const body = require('api-helper-lib/body');
const response = require('api-helper-lib/response');
const status = require('api-helper-lib/status');

API

query — parseQuery, getQueryParam, stringifyQuery, mergeQuery

headers — getHeader, getBearerToken, getContentType, isJsonRequest, corsHeaders, jsonHeaders

body — readBody, parseBody, parseJsonSafe

response — jsonResponse, successResponse, errorResponse, notFoundResponse, unauthorizedResponse, validationErrorResponse, paginatedResponse

status — STATUS, STATUS_TEXT, getStatusText, isSuccess, isClientError, isServerError

License

MIT