static encodeMetricsReportMessage(body) {
        const report = JSON.stringify(body);
        const buf = Buffer.alloc(report.length + headerSize);
        buf.writeUInt8(MessageType.METRICS_REPORT_MESSAGE, 0);
        buf.writeUInt8(0, 1);
        buf.writeUInt8(TargetType.TARGET_ANY, 2);
        buf.write(report, headerSize);
        return buf;
    }
Creates a wire representation of a metrics message

@param  {object} body Metrics report

@returns {Buffer} wire representation