json_schema: {
      "$schema": "http://json-schema.org/draft-04/schema#",
      "type": "object",
      "title": "EnvSensor4 tempEvent Schema",
      "description": "defines the structure of a temperature event in degrees Fahrenheit ",
      "properties": {
          "temp": {
              "description": "temperature in degrees Fahrenheit",
              "type": "number",
              "minimum": -459.67,
              "default": 75.0
          }
      },
      "required": [
          "temp"
      ]
  }