<log4j:event logger="WorkOrdersApi.Filters.RequestLoggerFilter" timestamp="1475666070747" level="DEBUG" 
thread="7"><log4j:message>Request recieved: Uri=/debug/version</log4j:message>

The segment starts with

log4j:event

Then logger, timestamp, level, and thread are attributes within this segment. In the above there is not an ending to this segment; i.e.

</log4j:event>

You can use DOM to extract the segments and then get a list of the attributes. In java this would be:

var foo = document.getElementById('foo'),
    attrs = foo.attributes,
    i = attrs.length,
    attr;

while (i--)
{
    attr = attrs[i];
    console.log(attr.name + '="' + attr.value + '"');
}

You can convert the above to VFP.