TimberWinR/TimberWinR.ServiceHost/loopback.json

{
    "TimberWinR": {
        "Inputs": {           
            "Stdin": [
                {
                }
            ]
        },      
        "Outputs": {
            "Stdout": [
                { 
                }
            ]
        },
		"Filters": [          
            {
                "grok": {
                    "match": [
                        "message",
                        ""
                    ],                   
                    "add_field": [
                        "ComputerName", "test"                   
                    ]
                }
            }
		]
    }
}