koa-ping-healthcheck

Make koa apps check internal status and health. This project is inspired by express-ping

Usage

• Save "koa-ping-healthcheck" to your package.json dependencies npm install koa-ping-healthcheck --save
• Include the middleware in your koa application:

const health = require("koa-ping-healthcheck");
const Koa = require("koa");

const app = new Koa();

app.use(health());

app.listen(3000);

Once you launch your koa application, it will add a new /ping endpoint to check the app status. If you GET http://localhost:3000/ping you will receive the following information:

{
  "custom": {},
  "timestamp": 1416079378823,
  "uptime": 550.219,
  "application": {
    "name": "koa-ping-healthcheck",
    "version": "1.0.0",
    "pid": 21149,
    "title": "node",
    "argv": ["node", "/koa-ping-healthcheck/index.js"],
    "versions": {
      "http_parser": "2.3",
      "node": "0.11.14",
      "v8": "3.26.33",
      "uv": "1.0.0",
      "zlib": "1.2.3",
      "modules": "14",
      "openssl": "1.0.1i"
    }
  },
  "resources": {
    "memory": {
      "rss": 26243072,
      "heapTotal": 17930752,
      "heapUsed": 10810544
    },
    "loadavg": [4.431640625, 4.572265625, 4.451171875],
    "cpu": [
      {
        "model": "Intel(R) Core(TM) i5-4250U CPU @ 1.30GHz",
        "speed": 1300,
        "times": {
          "user": 43839420,
          "nice": 0,
          "sys": 24282010,
          "idle": 164757040,
          "irq": 0
        }
      },
      {
        "model": "Intel(R) Core(TM) i5-4250U CPU @ 1.30GHz",
        "speed": 1300,
        "times": {
          "user": 23479990,
          "nice": 0,
          "sys": 10831830,
          "idle": 198556920,
          "irq": 0
        }
      },
      {
        "model": "Intel(R) Core(TM) i5-4250U CPU @ 1.30GHz",
        "speed": 1300,
        "times": {
          "user": 42303960,
          "nice": 0,
          "sys": 18350510,
          "idle": 172214370,
          "irq": 0
        }
      },
      {
        "model": "Intel(R) Core(TM) i5-4250U CPU @ 1.30GHz",
        "speed": 1300,
        "times": {
          "user": 23728510,
          "nice": 0,
          "sys": 9963050,
          "idle": 199177080,
          "irq": 0
        }
      }
    ],
    "disk": [
      {
        "filesystem": "/dev/disk1",
        "size": 117286912,
        "used": 92423484,
        "available": 24607428,
        "capacity": 0.79,
        "mount": "/"
      },
      {
        "filesystem": "devfs",
        "size": 180,
        "used": 180,
        "available": 0,
        "capacity": 1,
        "mount": "/dev"
      },
      {
        "filesystem": "map -hosts",
        "size": 0,
        "used": 0,
        "available": 0,
        "capacity": 1,
        "mount": "/net"
      },
      {
        "filesystem": "map auto_home",
        "size": 0,
        "used": 0,
        "available": 0,
        "capacity": 1,
        "mount": "/home"
      }
    ],
    "nics": {
      "lo0": [
        {
          "address": "::1",
          "netmask": "ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff",
          "family": "IPv6",
          "mac": "00:00:00:00:00:00",
          "scopeid": 0,
          "internal": true
        },
        {
          "address": "127.0.0.1",
          "netmask": "255.0.0.0",
          "family": "IPv4",
          "mac": "00:00:00:00:00:00",
          "internal": true
        },
        {
          "address": "fe80::1",
          "netmask": "ffff:ffff:ffff:ffff::",
          "family": "IPv6",
          "mac": "00:00:00:00:00:00",
          "scopeid": 1,
          "internal": true
        }
      ],
      "en0": [
        {
          "address": "fe80::8638:35ff:fe41:a48c",
          "netmask": "ffff:ffff:ffff:ffff::",
          "family": "IPv6",
          "mac": "84:38:35:41:a4:8c",
          "scopeid": 4,
          "internal": false
        },
        {
          "address": "192.168.1.100",
          "netmask": "255.255.255.0",
          "family": "IPv4",
          "mac": "84:38:35:41:a4:8c",
          "internal": false
        }
      ],
      "awdl0": [
        {
          "address": "fe80::8df:54ff:fe9e:d53b",
          "netmask": "ffff:ffff:ffff:ffff::",
          "family": "IPv6",
          "mac": "0a:df:54:9e:d5:3b",
          "scopeid": 7,
          "internal": false
        }
      ]
    }
  },
  "system": {
    "arch": "x64",
    "platform": "darwin",
    "type": "Darwin",
    "release": "14.0.0",
    "hostname": "MyPC",
    "uptime": 1802594,
    "cores": 4,
    "memory": 8589934592
  }
}

Configuration

You don't need to configure anything. By default, a /ping endpoint will be added to your routes, but you can pass the ping endpoint to the middeware simply doing:

app.use(health.ping({ path: "/custompath" }));

You can also pass a custom checker, use customCheckOnly option if you want to display only the custom checker's output:

app.use(
  healthCheck({
    customCheckOnly: false, //set to true to display only the output from custom checker
    customCheck: async function customHealthCheck(ctx) {
      const start = Date.now();

      await pingDatabase();

      return {
        ua: ctx.request.get("user-agent"),
        databaseLatency: `${Date.now() - start} ms`
      };
    }
  })
);

Which will output:

{
  "custom": {
    "ua": "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_13_4) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/71.0.3562.0 Safari/537.36",
    "databaseLatency": "22 ms"
  },
  "timestamp": 1416079378823,
  "uptime": 550.219
}

Notes

• Thanks to Guido García @palmerabollo
• Debate around the JSON organization see on express-ping wiki (contributions are welcome).