node-health-agent

Node agent for Node health project.

Purpose

Agent to trigger events in your instances (even on production). It comes with a list of built-in events and allows to trigger custom actions.

Compatibility

/!\ This module use async/await syntax and the inspector module, this is why you must have node 8.0+.

Supported and tested : >= 8.0

Version	Supported	Tested
14.x	yes	yes
12.x	yes	yes

In order to have all features we recommend to use at least Node.js version 10 or higher.

Installation

$ npm install node-health-agent --save

Usage

Basic

const agent = require('node-health-agent')({
  appName: 'testAPI',
  serverUrl: 'ws://localhost:3001',
  inspector: {
    storage: {
      type: "s3",
      bucket: process.env.CONFIG_S3_BUCKET,
      dir: 'inspector'
    }
  }
})

Add a custom event

agent.addEvent('myEvent', (event) => {
  console.log(event)
})

Add a custom event and send data to server

agent.addEvent('myEvent', (event, ws) => {
  const data = ... // get data in any way
  event.data = data
  ws.send(JSON.stringify(event))
})

Trigger event manually

agent._events.cpu_profiling_start({}, agent.ws, agent.inspector)
// ...
// a few moment later
const profile = await agent._events.cpu_profiling_stop({}, agent.ws, agent.inspector)

List of built-in events

Event	description
cpu_profiling_start	Start a CPU profiling
cpu_profiling_stop	Stop a CPU profiling
extract_env_var	Extract environment variables
extract_package_file	Extract package.json file content
extract_dependencies	Extract the full dependencies tree
memory_dump	Take a memory snapshot
memory_sampling_start	Start a memory sampling
memory_sampling_stop	Stop memory sampling
code_coverage_start	Start to collect code coverage data
code_coverage_stop	Stop code coevrage and send data
diagnosis_report	Run Node.js diagnosis report
memory_cpu_usage	Export CPU and memory info

Debug

Node-health's agent use debug module in order not to pollute your logs. If you want to see all agent output just use DEBUG environment variable:

DEBUG=node-health-agent* node myApp.js

Test

$ npm test

Coverage report can be found in coverage/.