Only ask for sudo password when required

Check nmcli permissions and only ask for password if required.

Move getpass to separate func and validate password input using assert
Otherwise raise AssertionError

Change sudo func to return an empty string if no sudo password is
provided in order to prevent formating of the nmcli commands with sudo
prefix if not required.
Raise condition is moved at password input.

This commit solves gopro#483

demos/python/sdk_wireless_camera_control/open_gopro/wifi/adapters/wireless.py

@@ -117,15 +117,16 @@ def _detect_driver(self) -> WifiController:
         if which("networksetup"):
             return NetworksetupWireless()
 
-        # Try Linux options. Need password for sudo
-        if not self._password:
-            self._password = getpass("Need to run as sudo. Enter password: ")
-        # Validate password
-        if "VALID PASSWORD" not in cmd(f'echo "{self._password}" | sudo -S echo "VALID PASSWORD"'):
-            raise RuntimeError("Invalid password")
-
+        # Try Linux options.
         # try nmcli (Ubuntu 14.04). Allow for use in Snap Package
         if which("nmcli") or which("nmcli", path="/snap/bin/"):
+
+            ctrl_wifi = cmd("nmcli general permissions |grep enable-disable-wifi")
+            scan_wifi = cmd("nmcli general permissions |grep scan")
+
+            if not "yes" in ctrl_wifi or not "yes" in scan_wifi:
+                self._sudo_from_stdin()
+
             version = cmd("nmcli --version").split()[-1]
             # On RHEL based systems, the version is in the form of 1.44.2-1.fc39
             # wich raises an error when trying to compare it with the Version class
@@ -138,10 +139,27 @@ def _detect_driver(self) -> WifiController:
             )
         # try nmcli (Ubuntu w/o network-manager)
         if which("wpa_supplicant"):
+            self._sudo_from_stdin()
             return WpasupplicantWireless(password=self._password)
 
         raise RuntimeError("Unable to find compatible wireless driver.")
 
+    def _sudo_from_stdin(self) -> str:
+        """Ask for sudo password input from stdin
+
+        Returns:
+            str: password
+        """
+        # Need password for sudo
+        if not self._password:
+            self._password = getpass("Need to run as sudo. Enter password: ")
+            assert self._password, 'Password is required'
+        # Validate password
+        if "VALID PASSWORD" not in cmd(f'echo "{self._password}" | sudo -S echo "VALID PASSWORD"'):
+            raise RuntimeError("Invalid password")
+
+        return self._password
+
     @pass_through_to_driver
     def connect(self, ssid: str, password: str, timeout: float = 15) -> bool:  # type: ignore
         """Connect to a network.

demos/python/sdk_wireless_camera_control/open_gopro/wifi/controller.py

@@ -143,12 +143,9 @@ def is_on(self) -> bool:
     def sudo(self) -> str:
         """Return the sudo encapsulated password
 
-        Raises:
-            RuntimeError: No password has been supplied
-
         Returns:
             str: echo "**********" | sudo -S
         """
         if not self._password:
-            raise RuntimeError("Can't use sudo with empty password.")
+            return ""
         return f'echo "{self._password}" | sudo -S'