export generates valid but not well-formatted json

[dfang]

like this, many empty key value pair in output json

{
    "users": {
        "15d99242e9f7235d220d": {
            "": "",
            "id": "15d99242e9f7235d220d"
        },
        "166e8c2e5ca2eaa67376": {
            "": "",
            "id": "166e8c2e5ca2eaa67376"
        },
        "99d3bd56485b8f3893cf": {
            "": "",
            "id": "99d3bd56485b8f3893cf"
        }
    }
}