req-logger

package.json

{
  "name": "req-dump",
  "version": "1.0.0",
  "description": "",
  "main": "server.js",
  "bin": "server.js",
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1",
    "start": "node server.js"
  },
  "author": "Sankaran Kaliappan <mail@sankarank.in>",
  "license": "ISC",
  "dependencies": {
    "body-parser": "^1.19.0",
    "express": "^4.17.1"
  }
}

server.js

#!/usr/bin/env node

const express = require('express')
const bodyParser = require('body-parser')
const fs = require('fs')
const app = express()
const port = process.env.PORT || 3000

function array2csv(data) {
  const replacer = (key, value) => value === null ? '' : value // specify how you want to handle null values here
  const header = Object.keys(data[0])
  const csv = [
    header.join(','), // header row first
      ...data.map(row => header.map(fieldName => JSON.stringify(row[fieldName], replacer)).join(','))
  ].join('\r\n')
  return csv;
}

// send formated json response
app.set('json spaces', 2)

// parse application/x-www-form-urlencoded
app.use(bodyParser.urlencoded({ extended: true }))

// parse application/json
app.use(bodyParser.json({ limit: '10mb' }))

// parse an HTML body into a string
app.use(bodyParser.text({ type: 'text/html' }))

app.post('/json2csv', (req, res) => {
    const outputFilename = `./${req.body.file_name || 'output'}.csv`;
    fs.writeFileSync(outputFilename, array2csv(req.body.payload)); // write to the file system
    res.json({output: outputFilename});
});

app.all('*', (req, res) => {
  const { headers, method, url, body, query } = req
  console.log({ headers, method, url, body, query })
  res.send({
    headers, method, url, body, query,
  })
})

app.listen(port, () => console.log(`listening at http://localhost:${port}`))