macosapplescriptnetwork-servicesystem-preferencessystemevent

AppleScript - determine the network service to which the current IP address is bound


The following AppleScript code will return all the network services in the Network Setup.

tell application "System Events"
        tell current location of network preferences
            set names to get name of every service
        end tell
 end tell

How do I get only the active network service name instead of all?

Update with clarification: 'active' in this context means the network service to whose interface the current [primary] IPv4 address is bound.


Solution

  • @mcgrailm's answer shows you how to obtain all active (read: not disabled) network services, whether currently bound to addresses or not.

    This answer, by contrast, shows you how to determine the network service to whose interface the current (primary) IPv4 address is bound:

    Unfortunately, this is non-trivial, as the information must be drawn from several sources:

    # Obtain the [network] `service` instance underlying the 
    # current IPv4 address...
    set serviceWithPrimaryIpv4Address to my networkServiceByIp4Address("")
    # ... and extract the name.
    set nameOfServiceWithPrimaryIpv4Address to name of serviceWithPrimaryIpv4Address
    
    # ---- Helper handlers.
    
    # SYNOPSIS
    #   networkServiceByIp4Address([addr])
    # DESCRIPTION
    #   Given (one of) the local system's IPv4 address(es), returns the network service object whose interface
    #   the address is bound to (class `network service` is defined in `Sytem Events.sdef`).
    #   If `addr` is an empty string or a missing value, the current primary IPv4 address is used.
    #  An error is thrown if no matching service is found.
    on networkServiceByIp4Address(addr)
      local macAddress
      set macAddress to my ip4ToMacAddress(addr)
      tell application "System Events"
        try
          tell current location of network preferences
            return first service whose (MAC address of interface of it) is macAddress
          end tell
        end try
      end tell
      error "No network service found matching IP address '" & addr & "'." number 500
    end networkServiceByIp4Address
    
    # SYNOPSIS
    #   ip4ToMacAddress([addr])
    # DESCRIPTION
    #   Given (one of) the local system's IPv4 address(es), returns the corresponding network interface's
    #   MAC address (regardless of interface type).
    #   If `addr` is an empty string or a missing value, the current primary IPv4 address is used.
    #  An error is thrown if no matching MAC address is found.
    on ip4ToMacAddress(addr)
      if addr as string is "" then set addr to IPv4 address of (system info)
      try
        do shell script "ifconfig | awk -v ip4=" & ¬
          quoted form of addr & ¬
          " 'NF==2 && $2 ~ /^[a-f0-9]{2}(:[a-f0-9]{2}){5}$/ {macAddr=$2; next} $1 == \"inet\" && $2 == ip4 {print macAddr; exit}'"
        if result ≠ "" then return result
      end try
      error "No MAC address found matching IP address '" & addr & "'." number 500
    end ip4ToMacAddress
    
    my ip4ToMacAddress("")