example node fetch distributed tracing

index.js

// cd into root of this directory
// npm install
// npm install -g http-echo-server
// new terminal window from run `http-echo-server`
// node index.js
// see output that server receives in output.txt

tracer = require('dd-trace').init()

const fetch = require('node-fetch');
const testUrl = 'http://localhost:3000/hello'

fetch(testUrl)
  .then(res => {
    return res
  }).then(output => {
    console.log(output)
  })

output.txt

COMP10929:node-fetch-stuff $ http-echo-server
[server] event: listening (port: 3000)
[server] event: connection (socket#1)
[socket#1] event: resume
[socket#1] event: data
--> GET /hello HTTP/1.1
--> Accept: */*
--> User-Agent: node-fetch/1.0 (+https://github.com/bitinn/node-fetch)
--> Accept-Encoding: gzip,deflate
--> Connection: close
--> x-datadog-trace-id: 2894019178293600090
--> x-datadog-parent-id: 2894019178293600090
--> x-datadog-sampled: 1
--> x-datadog-sampling-priority: 1
--> Host: localhost:3000
--> 
--> 
[socket#1] event: prefinish
[socket#1] event: finish
[socket#1] event: readable
[socket#1] event: end
[socket#1] event: close

package.json

{
  "name": "exampe_distributed_headers",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1"
  },
  "author": "Eric Mustin",
  "license": "ISC",
  "dependencies": {
    "dd-trace": "^0.17.1",
    "http-echo-server": "^2.1.1",
    "node-fetch": "^2.6.0"
  }
}