[{
    "name":"foo",
    "properties":{
        "version":"1.3.0.0",
        "upgradePolicy": "manual",
        "state": "enabled",
        "extensions":[{
            "name":"baz",
            "sequenceNumber":0,
            "publicSettings":{
                "commandToExecute": "echo 123",
                "uris":[]
            }
        }]
    },
    "versionUris":[{
        "uri":"http://ext_handler_pkgs/versionUri"
    }]
}]