{
    "id": "/PingResponse",
    "title": "Ping Response",
    "type": "object",
    "properties": {
        "checksum": {
            "type": "number"
        },
        "changes": {
            "type": "array",
            "items": {
                "$ref": "/Change"
            }
        },
        "source": {
            "type": "string"
        },
        "sourceIncarnationNumber": {
            "type": "number"
        },
        "target": {
            "type": "string"
        }
    },
    "required": [
        "changes"
    ],
    "additionalProperties": false
}

{
    "id": "/PingResponse",
    "title": "Ping Response",
    "type": "object",
    "properties": {
        "checksum": {
            "type": "number"
        },
        "changes": {
            "type": "array",
            "items": {
                "$ref": "/Change"
            }
        },
        "source": {
            "type": "string"
        },
        "app": {
            "type": "string"
        },
        "sourceIncarnationNumber": {
            "type": "number"
        },
        "target": {
            "type": "string"
        }
    },
    "required": [
        "changes"
    ],
    "additionalProperties": false
}

Add optional app field in ping response
Add optional app field in ping response
