json_schema: {
      "$schema": "http://json-schema.org/draft-04/schema#",
      "title": "Lobby server set",
      "description": "A set of lobby servers",
      "type": "array",
      "items": {
          "title": "Lobby server",
          "description": "A lobby server",
          "type": "object",
          "properties": {
              "version": {
                  "description": "The lobby server engine version",
                  "type": "string",
                  "pattern": "^\\d+(\\.\\d+){1,3}$"
              },
              "host": {
                  "description": "The lobby server host",
                  "type": "string",
                  "anyOf": [
                      {
                          "format": "host-name"
                      },
                      {
                          "format": "ipv4"
                      },
                      {
                          "format": "ipv6"
                      }
                  ]
              },
              "port": {
                  "description": "The TCP port on which the lobby server accepts connections",
                  "type": "number",
                  "minimum": 0,
                  "maximum": 65535
              },
              "https_port": {
                  "description": "Https lobby server port",
                  "type": "number",
                  "minimum": 0,
                  "maximum": 65535
              },
              "message": {
                  "description": "The message displayed when a user connects to an available lobby server",
                  "type": [
                      "string",
                      "null"
                  ]
              },
              "error_message": {
                  "description": "The message displayed when a user connects to an unavailable lobby server",
                  "type": [
                      "string",
                      "null"
                  ]
              }
          },
          "required": [
              "version",
              "host",
              "port",
              "https_port",
              "message",
              "error_message"
          ],
          "additionalProperties": false
      }
  }