[Feature Request] application/health+json format

[ejunker]

I am not sure if this is within the scope of this project but there is a proposed standard for health data.

More detailed information can be found at:
https://inadarei.github.io/rfc-healthcheck/

Example response format:

  GET /health HTTP/1.1
  Host: example.org
  Accept: application/health+json

  HTTP/1.1 200 OK
  Content-Type: application/health+json
  Cache-Control: max-age=3600
  Connection: close

{
  "status": "pass",
  "version": "1",
  "releaseID": "1.2.2",
  "notes": [""],
  "output": "",
  "serviceID": "f03e522f-1f44-4062-9b55-9587f91c9c41",
  "description": "health of authz service",
  "details": {
    "cassandra:responseTime": [
      {
        "componentId": "dfd6cf2b-1b6e-4412-a0b8-f6f7797a60d2",
        "componentType": "datastore",
        "metricValue": 250,
        "metricUnit": "ms",
        "status": "pass",
        "time": "2018-01-17T03:36:48Z",
        "output": ""
      }
    ],
    "cassandra:connections": [
      {
        "componentId": "dfd6cf2b-1b6e-4412-a0b8-f6f7797a60d2",
        "type": "datastore",
        "metricValue": 75,
        "status": "warn",
        "time": "2018-01-17T03:36:48Z",
        "output": "",
        "links": {
          "self": "http://api.example.com/dbnode/dfd6cf2b/health"
        }
      }
    ],
    "uptime": [
      {
        "componentType": "system",
        "metricValue": 1209600.245,
        "metricUnit": "s",
        "status": "pass",
        "time": "2018-01-17T03:36:48Z"
      }
    ],
    "cpu:utilization": [
      {
        "componentId": "6fd416e0-8920-410f-9c7b-c479000f7227",
        "node": 1,
        "componentType": "system",
        "metricValue": 85,
        "metricUnit": "percent",
        "status": "warn",
        "time": "2018-01-17T03:36:48Z",
        "output": ""
      },
      {
        "componentId": "6fd416e0-8920-410f-9c7b-c479000f7227",
        "node": 2,
        "componentType": "system",
        "metricValue": 85,
        "metricUnit": "percent",
        "status": "warn",
        "time": "2018-01-17T03:36:48Z",
        "output": ""
      }
    ],
    "memory:utilization": [
      {
        "componentId": "6fd416e0-8920-410f-9c7b-c479000f7227",
        "node": 1,
        "componentType": "system",
        "metricValue": 8.5,
        "metricUnit": "GiB",
        "status": "warn",
        "time": "2018-01-17T03:36:48Z",
        "output": ""
      },
      {
        "componentId": "6fd416e0-8920-410f-9c7b-c479000f7227",
        "node": 2,
        "componentType": "system",
        "metricValue": 5500,
        "metricUnit": "MiB",
        "status": "pass",
        "time": "2018-01-17T03:36:48Z",
        "output": ""
      }
    ]
  },
  "links": {
    "about": "http://api.example.com/about/authz",
    "http://api.x.io/rel/thresholds":
      "http://api.x.io/about/authz/thresholds"
  }
}