Proposed Cisco WLC fix for session_preparation() problems (#2822)

netmiko/cisco/cisco_wlc_ssh.py

@@ -11,11 +11,7 @@
 class CiscoWlcSSH(BaseConnection):
     """Netmiko Cisco WLC support."""
 
-    def __init__(self, *args: Any, **kwargs: Any) -> None:
-        # WLC/AireOS has an issue where you can get "No Existing Session" with
-        # the default conn_timeout (so increase conn_timeout to 10-seconds).
-        kwargs.setdefault("conn_timeout", 10)
-        return super().__init__(*args, **kwargs)
+    prompt_pattern = r"(?m:[>#]\s*$)"  # force re.Multiline
 
     def special_login_handler(self, delay_factor: float = 1.0) -> None:
         """WLC presents with the following on login (in certain OS versions)
@@ -28,25 +24,51 @@ def special_login_handler(self, delay_factor: float = 1.0) -> None:
 
         Password:****
         """
-        delay_factor = self.select_delay_factor(delay_factor)
-        i = 0
-        time.sleep(delay_factor * 0.5)
         output = ""
-        while i <= 12:
-            output = self.read_channel()
-            if output:
-                if "login as" in output or "User:" in output:
-                    assert isinstance(self.username, str)
-                    self.write_channel(self.username + self.RETURN)
-                elif "Password" in output:
-                    assert isinstance(self.password, str)
-                    self.write_channel(self.password + self.RETURN)
-                    break
-                time.sleep(delay_factor * 1)
+        uname = "User:"
+        login = "login as"
+        password = "ssword"
+        pattern = rf"(?:{uname}|{login}|{password}|{self.prompt_pattern})"
+
+        while True:
+            new_data = self.read_until_pattern(pattern=pattern, read_timeout=25.0)
+            output += new_data
+            if re.search(self.prompt_pattern, new_data):
+                return
+
+            if uname in new_data or login in new_data:
+                assert isinstance(self.username, str)
+                self.write_channel(self.username + self.RETURN)
+            elif password in new_data:
+                assert isinstance(self.password, str)
+                self.write_channel(self.password + self.RETURN)
             else:
-                # no output read, sleep and go for one more round of read channel
-                time.sleep(delay_factor * 1.5)
-            i += 1
+                msg = f"""
+Failed to login to Cisco WLC Device.
+
+Pattern not detected: {pattern}
+output:
+
+{output}
+
+"""
+                raise NetmikoAuthenticationException(msg)
+
+    def session_preparation(self) -> None:
+        """
+        Prepare the session after the connection has been established
+
+        Cisco WLC uses "config paging disable" to disable paging
+        """
+
+        # _test_channel_read() will happen in the special_login_handler()
+        try:
+            self.set_base_prompt()
+        except ValueError:
+            msg = f"Authentication failed: {self.host}"
+            raise NetmikoAuthenticationException(msg)
+
+        self.disable_paging(command="config paging disable")
 
     def send_command_w_enter(self, *args: Any, **kwargs: Any) -> str:
         """
@@ -145,22 +167,6 @@ def _send_command_w_yes(self, *args: Any, **kwargs: Any) -> str:
             output = self.strip_prompt(output)
         return output
 
-    def session_preparation(self) -> None:
-        """
-        Prepare the session after the connection has been established
-
-        Cisco WLC uses "config paging disable" to disable paging
-        """
-        self._test_channel_read(pattern=r"[>#]")
-
-        try:
-            self.set_base_prompt()
-        except ValueError:
-            msg = f"Authentication failed: {self.host}"
-            raise NetmikoAuthenticationException(msg)
-
-        self.disable_paging(command="config paging disable")
-
     def cleanup(self, command: str = "logout") -> None:
         """Reset WLC back to normal paging and gracefully close session."""
         self.send_command_timing("config paging enable")

netmiko/extreme/extreme_ers_ssh.py

@@ -50,7 +50,7 @@ def special_login_handler(self, delay_factor: float = 1.0) -> None:
                 self.write_channel(self.password + self.RETURN)
             else:
                 msg = f"""
-Failed to login to Extreme ERS Devices.
+Failed to login to Extreme ERS Device.
 
 Pattern not detected: {pattern}
 output: