schema.json

{
  "$schema": "http://json-schema.org/draft-07/schema#",
  "type": "object",
  "properties": {
    "version": {
      "type": "string",
      "pattern": "^(\\d+\\.\\d+\\.\\d+)$"
    },
    "newsEntries": {
      "type": "array",
      "items": {
        "type": "object",
        "properties": {
          "id": {
            "type": "integer"
          },
          "level": {
            "type": "array",
            "items": {
              "type": "integer",
              "minimum": 1,
              "maximum": 5
            },
            "uniqueItems": true
          },
          "individuallyCloseable": {
            "type": "boolean"
          },
          "nextEntryID": {
            "type": "integer"
          },
          "startDate": {
            "type": "integer"
          },
          "endDate": {
            "type": "integer"
          },
          "publishDate": {
            "type": "integer"
          },
          "counterActive": {
            "type": "boolean"
          },
          "counterEndDate": {
            "type": "integer"
          },
          "buttonActive": {
            "type": "boolean"
          },
          "buttonText": {
            "type": "object",
            "patternProperties": {
              "^[a-z]{2}$": {
                "type": "string"
              }
            },
            "required": ["en"]
          },
          "buttonLink": {
            "anyOf": [
              {
                "type": "string",
                "format": "uri"
              },
              {
                "type": "string",
                "enum": [""]
              }
            ]
          },
          "headline": {
            "type": "object",
            "patternProperties": {
              "^[a-z]{2}$": {
                "type": "string"
              }
            },
            "required": ["en"]
          },
          "infotext": {
            "type": "object",
            "patternProperties": {
              "^[a-z]{2}$": {
                "type": "string"
              }
            },
            "required": ["en"]
          },
          "imageUrl": {
            "type": "string",
            "format": "uri"
          }
        },
        "required": ["id", "level", "individuallyCloseable", "nextEntryID", "startDate", "endDate", "publishDate", "counterActive", "counterEndDate", "buttonActive", "buttonText", "buttonLink", "headline", "infotext", "imageUrl"]
      }
    }
  },
  "required": ["version", "newsEntries"]
}