Core WLAN MCS Index? - swift

Question

I'm trying to recreate the information displayed for the current Wi-Fi network when option-clicking on the Wi-Fi status bar item. One of the parameters shown is the MCS Index, but I can't find any way to query this value using the CWInterface class, which is where I am getting most of the other data:
if let interface = CWWiFiClient.shared().interface() {
rssi = interface.rssiValue()
noise = interface.noiseMeasurement()
// etc.
}
Since both the Wi-Fi status bar item and the airport command line tool display the MCS Index, it seems like there should be some way to query it:
MacBook:~ mark$ /System/Library/PrivateFrameworks/Apple80211.framework/Versions/Current/Resources/airport -I
agrCtlRSSI: -46
agrExtRSSI: 0
agrCtlNoise: -90
agrExtNoise: 0
state: running
op mode: station
lastTxRate: 878
maxRate: 1300
lastAssocStatus: 0
802.11 auth: open
link auth: wpa2-psk
BSSID: xx:xx:xx:xx:xx:xx
SSID: MyWiFi
MCS: 7
channel: 149,80
I've also seem some Python sample code that seems to indicate that the MCS Index should be available, but I don't see it in the docs or code completion.
Is there some way to get this value through Core WLAN or some other framework, or is this something I need to calculate based on other values?

Answer 1

I found another Python script wifi_status.py
which reports the WiFi status. From the lines
def wifi_status(properties=('bssid', 'channel', 'txRate', 'mcsIndex', 'rssi', 'noise')):
xface = CWWiFiClient.sharedWiFiClient().interface()
while True:
yield({name: getattr(xface, name)() for name in properties})
one can conclude that these attributes can be retrieved with
Key-Value Coding.
And that really works:
if let iface = CWWiFiClient.shared().interface() {
if let mcsIndex = iface.value(forKey: "mcsIndex") as? Int {
print(mcsIndex)
}
}
But I have now idea if that approach is officially supported,
or will work in the future, so use at your own risk.