Create method to find currently connected network interface

Create method to find currently connected network interface

sssd_test_framework/utils/tools.py

@@ -515,6 +515,31 @@ def grep(self, pattern: str, paths: str | list[str], args: list[str] | None = No
 
         return command.rc == 0
 
+    def connected_interface(self) -> str:
+        """
+        Retrieves the currently connected network interface on a Linux system by executing the
+        'ip route show default' command on a remote host.
+
+        This method uses the `exec` method of the `host.conn` object to run the 'ip route show default'
+        command on the remote host. It then parses the output to determine the network interface
+        used for the default route.
+
+        Returns:
+            str: The name of the connected network interface (e.g., 'eth0', 'wlan0') if found.
+                 If the command fails, returns empty string.
+
+        Example:
+            >>> client.tools.connected_interface()
+            'eth0'
+        """
+        result = self.host.conn.exec(["ip", "route", "show", "default"])
+        if result.rc == 0:
+            output = result.stdout.strip()
+            if output:
+                interface = output.split()[4]  # The interface name is the 5th field
+                return interface
+        return ""
+
     def tcpdump(self, pcap_path: str, args: list[Any] | None = None) -> SSHKillableProcess:
         """
         Run tcpdump. The packets are captured in ``pcap_path``.