example dd express hook

example_express_hook.js

// npm install

const tracer = require('dd-trace').init({debug: false})

tracer.use('express', {
  hooks: {
    request: (span, req, res) => {
	  console.log('express hook invoked')
      span.setTag('hook_tag_key', 'hook_tag_value')
	}
  }
})

const axios = require('axios')
const express = require('express')

const app = express()
const port = 5000

app.get('*', function(req, res) {
  console.log('responding')
  res.send('Hello World!')
})

app.listen(port, function() {
  console.log(`listening on port ${port}!`)
})


// $ curl localhost:5000

// ## SAMPLE OUTPUT

// ok
// express hook

package.json

{
  "name": "example_express_hook",
  "version": "1.0.0",
  "description": "",
  "main": "example_express_hook.js",
  "scripts": {
    "start": "node example_express_hook.js"
  },
  "author": "",
  "license": "ISC",
  "dependencies": {
    "axios": "^0.19.1",
    "dd-trace": "0.15.3",
    "express": "^4.17.1"
  }
}

example output