curl -X POST -H "Content-Type: application/json" -d '{
  "id": "gauge_test",
  "name": "Gauge Metric",
  "url": "http://127.0.0.1:8081/gauge",
  "method": "GET",
  "type": "gauge",
  "metrics": {
    "temperature": 36.6
  }
}' "http://localhost:9101/update"

curl http://localhost:9101/metrics