webuniverseio/superagent-node-http-timings

Measure http timings in node.js

yarn add superagent-node-http-timings
npm i --save superagent-node-http-timings

HTTP Timings

This plugin for superagent gives you an easy interface to get http timings information. Primary use case is to be able to monitor and optimize network requests in node in a similar way to how you do it in browser with network inspector.

Example

const request = require('superagent');
const logNetworkTime = require('superagent-node-http-timings');
request
  .get(`https://google.com`)
  .use(logNetworkTime((err, result) => {
    if (err) {
      return console.error(err);
    }
    console.log(result);
  }))
  .then(x => x);

Sample results (timings are in milliseconds)1:

{
  "status": 301,
  "timings": {
    "socketAssigned": 4.0982,
    "dnsLookup": 38.9614,
    "tcpConnection": 42.1931,
    "tlsHandshake": 105.221,
    "firstByte": 67.0892,
    "contentTransfer": 0.6482,
    "total": 258.2111
  },
  "url": "https://google.com"
}

Results interpretation

• socketAssigned - time since call was initiated until socket got assigned to request
• dnsLookup - time since socketAssigned until dns lookup end, will be undefined when request was sent to IP (no domain)
• tcpConnection - time since dnsLookup (or socketAssigned if IP was used) until connection was established
• tlsHandshake - time since tcpConnection until until ssl negotiation end, will be undefined when request was sent via http
• firstByte - time since tlsHandshake (or tcpConnection for http request) until first byte
• contentTransfer - time since firstByte until response end

Inspired by

• https://blog.risingstack.com/measuring-http-timings-node-js/
• https://github.com/RisingStack/example-http-timings

Contributing to this repo

PRs are welcome! :)