YAML body parser middleware for any Node.js framework

yaml.middleware.ts

import type { IncomingMessage, ServerResponse } from 'http';
import type { EventEmitter } from 'events';
import yaml from 'yaml'; // npm install yaml

type Next = (err?: any) => void;
type RequestWithBody<T = any> = IncomingMessage & { body?: T } & EventEmitter

async function parseYaml(req: RequestWithBody, _: ServerResponse, next: Next) {
  try {
    let body = '';
    for await (const chunk of req) body += chunk;
    req.body = yaml.parse(body);
    next();
  } catch (error) {
    next(error);
  }
}

export { parseYaml };

// Usage:
//
// const app = express()
// app.use(parseYaml())
//
// Can also be used on Tinyhttp, Polka, and other Express-flavor frameworks.