Re: [PATCH v2 4/7] dts: revert back to a single InteractiveShell

[Nicholas Pratte <npratte@iol.unh.edu>]

Reviewed-by: Nicholas Pratte <npratte@iol.unh.edu>

On Fri, Mar 14, 2025 at 9:19 AM Luca Vizzarro <luca.vizzarro@arm.com> wrote:
>
> Previously InteractiveShell was split into two classes to differentiate
> a shell which execution must be controlled in a tight scope through a
> context manager, from a more looser approach. With the addition of the
> shell pool this is no longer needed as the management of shells is now
> delegated to the test run instead of the test suites.
>
> Revert back to a single InteractiveShell to simplify the code. Keep the
> context manager implementation but also render start_application and
> close public methods again.
>
> Signed-off-by: Luca Vizzarro <luca.vizzarro@arm.com>
> Reviewed-by: Paul Szczepanek <paul.szczepanek@arm.com>
> ---
>  dts/framework/remote_session/dpdk_app.py      |   4 +-
>  dts/framework/remote_session/dpdk_shell.py    |   6 +-
>  .../remote_session/interactive_shell.py       | 289 ++++++++++++++++--
>  dts/framework/remote_session/python_shell.py  |   4 +
>  dts/framework/remote_session/shell_pool.py    |   2 +-
>  .../single_active_interactive_shell.py        | 275 -----------------
>  dts/framework/remote_session/testpmd_shell.py |   4 +-
>  7 files changed, 275 insertions(+), 309 deletions(-)
>  delete mode 100644 dts/framework/remote_session/single_active_interactive_shell.py
>
> diff --git a/dts/framework/remote_session/dpdk_app.py b/dts/framework/remote_session/dpdk_app.py
> index c9945f302d..c5aae05e02 100644
> --- a/dts/framework/remote_session/dpdk_app.py
> +++ b/dts/framework/remote_session/dpdk_app.py
> @@ -62,7 +62,7 @@ def wait_until_ready(self, end_token: str) -> None:
>          Args:
>              end_token: The string at the end of a line that indicates the app is ready.
>          """
> -        self._start_application(end_token)
> +        self.start_application(end_token)
>
>      def close(self) -> None:
>          """Close the application.
> @@ -70,4 +70,4 @@ def close(self) -> None:
>          Sends a SIGINT to close the application.
>          """
>          self.send_command("\x03")
> -        self._close()
> +        super().close()
> diff --git a/dts/framework/remote_session/dpdk_shell.py b/dts/framework/remote_session/dpdk_shell.py
> index f7ea2588ca..24a39482ce 100644
> --- a/dts/framework/remote_session/dpdk_shell.py
> +++ b/dts/framework/remote_session/dpdk_shell.py
> @@ -11,8 +11,8 @@
>
>  from framework.context import get_ctx
>  from framework.params.eal import EalParams
> -from framework.remote_session.single_active_interactive_shell import (
> -    SingleActiveInteractiveShell,
> +from framework.remote_session.interactive_shell import (
> +    InteractiveShell,
>  )
>  from framework.testbed_model.cpu import LogicalCoreList
>
> @@ -51,7 +51,7 @@ def compute_eal_params(
>      return params
>
>
> -class DPDKShell(SingleActiveInteractiveShell, ABC):
> +class DPDKShell(InteractiveShell, ABC):
>      """The base class for managing DPDK-based interactive shells.
>
>      This class shouldn't be instantiated directly, but instead be extended.
> diff --git a/dts/framework/remote_session/interactive_shell.py b/dts/framework/remote_session/interactive_shell.py
> index 9ca285b604..62f9984d3b 100644
> --- a/dts/framework/remote_session/interactive_shell.py
> +++ b/dts/framework/remote_session/interactive_shell.py
> @@ -1,44 +1,281 @@
>  # SPDX-License-Identifier: BSD-3-Clause
> -# Copyright(c) 2023 University of New Hampshire
> +# Copyright(c) 2024 University of New Hampshire
>  # Copyright(c) 2024 Arm Limited
>
> -"""Interactive shell with manual stop/start functionality.
> +"""Common functionality for interactive shell handling.
>
> -Provides a class that doesn't require being started/stopped using a context manager and can instead
> -be started and stopped manually, or have the stopping process be handled at the time of garbage
> -collection.
> +The base class, :class:`InteractiveShell`, is meant to be extended by subclasses that
> +contain functionality specific to that shell type. These subclasses will often modify things like
> +the prompt to expect or the arguments to pass into the application, but still utilize
> +the same method for sending a command and collecting output. How this output is handled however
> +is often application specific. If an application needs elevated privileges to start it is expected
> +that the method for gaining those privileges is provided when initializing the class.
> +
> +This class is designed for applications like primary applications in DPDK where only one instance
> +of the application can be running at a given time and, for this reason, is managed using a context
> +manager. This context manager starts the application when you enter the context and cleans up the
> +application when you exit. Using a context manager for this is useful since it allows us to ensure
> +the application is cleaned up as soon as you leave the block regardless of the reason.
> +
> +The :option:`--timeout` command line argument and the :envvar:`DTS_TIMEOUT`
> +environment variable configure the timeout of getting the output from command execution.
>  """
>
> -import weakref
> +from abc import ABC
> +from pathlib import PurePath
>  from typing import ClassVar
>
> -from .single_active_interactive_shell import SingleActiveInteractiveShell
> +from paramiko import Channel, channel
> +from typing_extensions import Self
> +
> +from framework.exception import (
> +    InteractiveCommandExecutionError,
> +    InteractiveSSHSessionDeadError,
> +    InteractiveSSHTimeoutError,
> +)
> +from framework.logger import DTSLogger, get_dts_logger
> +from framework.params import Params
> +from framework.settings import SETTINGS
> +from framework.testbed_model.node import Node
> +from framework.utils import MultiInheritanceBaseClass
> +
> +
> +class InteractiveShell(MultiInheritanceBaseClass, ABC):
> +    """The base class for managing interactive shells.
>
> +    This class shouldn't be instantiated directly, but instead be extended. It contains
> +    methods for starting interactive shells as well as sending commands to these shells
> +    and collecting input until reaching a certain prompt. All interactive applications
> +    will use the same SSH connection, but each will create their own channel on that
> +    session.
>
> -class InteractiveShell(SingleActiveInteractiveShell):
> -    """Adds manual start and stop functionality to interactive shells.
> +    Interactive shells are started and stopped using a context manager. This allows for the start
> +    and cleanup of the application to happen at predictable times regardless of exceptions or
> +    interrupts.
>
> -    Like its super-class, this class should not be instantiated directly and should instead be
> -    extended. This class also provides an option for automated cleanup of the application using a
> -    weakref and a finalize class. This finalize class allows for cleanup of the class at the time
> -    of garbage collection and also ensures that cleanup only happens once. This way if a user
> -    initiates the closing of the shell manually it is not repeated at the time of garbage
> -    collection.
> +    Attributes:
> +        is_alive: :data:`True` if the application has started successfully, :data:`False`
> +            otherwise.
>      """
>
> -    _finalizer: weakref.finalize
> -    #: One attempt should be enough for shells which don't have to worry about other instances
> -    #: closing before starting a new one.
> -    _init_attempts: ClassVar[int] = 1
> +    _node: Node
> +    _stdin: channel.ChannelStdinFile
> +    _stdout: channel.ChannelFile
> +    _ssh_channel: Channel
> +    _logger: DTSLogger
> +    _timeout: float
> +    _app_params: Params
> +    _privileged: bool
> +    _real_path: PurePath
> +
> +    #: The number of times to try starting the application before considering it a failure.
> +    _init_attempts: ClassVar[int] = 5
> +
> +    #: Prompt to expect at the end of output when sending a command.
> +    #: This is often overridden by subclasses.
> +    _default_prompt: ClassVar[str] = ""
> +
> +    #: Extra characters to add to the end of every command
> +    #: before sending them. This is often overridden by subclasses and is
> +    #: most commonly an additional newline character. This additional newline
> +    #: character is used to force the line that is currently awaiting input
> +    #: into the stdout buffer so that it can be consumed and checked against
> +    #: the expected prompt.
> +    _command_extra_chars: ClassVar[str] = ""
> +
> +    #: Path to the executable to start the interactive application.
> +    path: ClassVar[PurePath]
> +
> +    is_alive: bool = False
> +
> +    def __init__(
> +        self,
> +        node: Node,
> +        name: str | None = None,
> +        privileged: bool = False,
> +        path: PurePath | None = None,
> +        app_params: Params = Params(),
> +        **kwargs,
> +    ) -> None:
> +        """Create an SSH channel during initialization.
> +
> +        Additional keyword arguments can be passed through `kwargs` if needed for fulfilling other
> +        constructors in the case of multiple inheritance.
> +
> +        Args:
> +            node: The node on which to run start the interactive shell.
> +            name: Name for the interactive shell to use for logging. This name will be appended to
> +                the name of the underlying node which it is running on.
> +            privileged: Enables the shell to run as superuser.
> +            path: Path to the executable. If :data:`None`, then the class' path attribute is used.
> +            app_params: The command line parameters to be passed to the application on startup.
> +            **kwargs: Any additional arguments if any.
> +        """
> +        self._node = node
> +        if name is None:
> +            name = type(self).__name__
> +        self._logger = get_dts_logger(f"{node.name}.{name}")
> +        self._app_params = app_params
> +        self._privileged = privileged
> +        self._timeout = SETTINGS.timeout
> +        # Ensure path is properly formatted for the host
> +        self._update_real_path(path or self.path)
> +        super().__init__(**kwargs)
> +
> +    def _setup_ssh_channel(self):
> +        self._ssh_channel = self._node.main_session.interactive_session.session.invoke_shell()
> +        self._stdin = self._ssh_channel.makefile_stdin("w")
> +        self._stdout = self._ssh_channel.makefile("r")
> +        self._ssh_channel.settimeout(self._timeout)
> +        self._ssh_channel.set_combine_stderr(True)  # combines stdout and stderr streams
> +
> +    def _make_start_command(self) -> str:
> +        """Makes the command that starts the interactive shell."""
> +        start_command = f"{self._real_path} {self._app_params or ''}"
> +        if self._privileged:
> +            start_command = self._node.main_session._get_privileged_command(start_command)
> +        return start_command
> +
> +    def start_application(self, prompt: str | None = None) -> None:
> +        """Starts a new interactive application based on the path to the app.
> +
> +        This method is often overridden by subclasses as their process for starting may look
> +        different. Initialization of the shell on the host can be retried up to
> +        `self._init_attempts` - 1 times. This is done because some DPDK applications need slightly
> +        more time after exiting their script to clean up EAL before others can start.
>
> -    def start_application(self) -> None:
> -        """Start the application.
> +        Args:
> +            prompt: When starting up the application, expect this string at the end of stdout when
> +                the application is ready. If :data:`None`, the class' default prompt will be used.
>
> -        After the application has started, use :class:`weakref.finalize` to manage cleanup.
> +        Raises:
> +            InteractiveCommandExecutionError: If the application fails to start within the allotted
> +                number of retries.
>          """
> -        self._start_application()
> -        self._finalizer = weakref.finalize(self, self._close)
> +        self._setup_ssh_channel()
> +        self._ssh_channel.settimeout(5)
> +        start_command = self._make_start_command()
> +        self.is_alive = True
> +        for attempt in range(self._init_attempts):
> +            try:
> +                self.send_command(start_command, prompt)
> +                break
> +            except InteractiveSSHTimeoutError:
> +                self._logger.info(
> +                    f"Interactive shell failed to start (attempt {attempt+1} out of "
> +                    f"{self._init_attempts})"
> +                )
> +        else:
> +            self._ssh_channel.settimeout(self._timeout)
> +            self.is_alive = False  # update state on failure to start
> +            raise InteractiveCommandExecutionError("Failed to start application.")
> +        self._ssh_channel.settimeout(self._timeout)
> +
> +    def send_command(
> +        self, command: str, prompt: str | None = None, skip_first_line: bool = False
> +    ) -> str:
> +        """Send `command` and get all output before the expected ending string.
> +
> +        Lines that expect input are not included in the stdout buffer, so they cannot
> +        be used for expect.
> +
> +        Example:
> +            If you were prompted to log into something with a username and password,
> +            you cannot expect ``username:`` because it won't yet be in the stdout buffer.
> +            A workaround for this could be consuming an extra newline character to force
> +            the current `prompt` into the stdout buffer.
> +
> +        Args:
> +            command: The command to send.
> +            prompt: After sending the command, `send_command` will be expecting this string.
> +                If :data:`None`, will use the class's default prompt.
> +            skip_first_line: Skip the first line when capturing the output.
> +
> +        Returns:
> +            All output in the buffer before expected string.
> +
> +        Raises:
> +            InteractiveCommandExecutionError: If attempting to send a command to a shell that is
> +                not currently running.
> +            InteractiveSSHSessionDeadError: The session died while executing the command.
> +            InteractiveSSHTimeoutError: If command was sent but prompt could not be found in
> +                the output before the timeout.
> +        """
> +        if not self.is_alive:
> +            raise InteractiveCommandExecutionError(
> +                f"Cannot send command {command} to application because the shell is not running."
> +            )
> +        self._logger.info(f"Sending: '{command}'")
> +        if prompt is None:
> +            prompt = self._default_prompt
> +        out: str = ""
> +        try:
> +            self._stdin.write(f"{command}{self._command_extra_chars}\n")
> +            self._stdin.flush()
> +            for line in self._stdout:
> +                if skip_first_line:
> +                    skip_first_line = False
> +                    continue
> +                if line.rstrip().endswith(prompt):
> +                    break
> +                out += line
> +        except TimeoutError as e:
> +            self._logger.exception(e)
> +            self._logger.debug(
> +                f"Prompt ({prompt}) was not found in output from command before timeout."
> +            )
> +            raise InteractiveSSHTimeoutError(command) from e
> +        except OSError as e:
> +            self._logger.exception(e)
> +            raise InteractiveSSHSessionDeadError(
> +                self._node.main_session.interactive_session.hostname
> +            ) from e
> +        finally:
> +            self._logger.debug(f"Got output: {out}")
> +        return out
>
>      def close(self) -> None:
> -        """Free all resources using :class:`weakref.finalize`."""
> -        self._finalizer()
> +        """Close the shell.
> +
> +        Raises:
> +            InteractiveSSHTimeoutError: If the shell failed to exit within the set timeout.
> +        """
> +        try:
> +            # Ensure the primary application has terminated via readiness of 'stdout'.
> +            if self._ssh_channel.recv_ready():
> +                self._ssh_channel.recv(1)  # 'Waits' for a single byte to enter 'stdout' buffer.
> +        except TimeoutError as e:
> +            self._logger.exception(e)
> +            self._logger.debug("Application failed to exit before set timeout.")
> +            raise InteractiveSSHTimeoutError("Application 'exit' command") from e
> +        self._ssh_channel.close()
> +
> +    def _update_real_path(self, path: PurePath) -> None:
> +        """Updates the interactive shell's real path used at command line."""
> +        self._real_path = self._node.main_session.join_remote_path(path)
> +
> +    def __enter__(self) -> Self:
> +        """Enter the context block.
> +
> +        Upon entering a context block with this class, the desired behavior is to create the
> +        channel for the application to use, and then start the application.
> +
> +        Returns:
> +            Reference to the object for the application after it has been started.
> +        """
> +        self.start_application()
> +        return self
> +
> +    def __exit__(self, *_) -> None:
> +        """Exit the context block.
> +
> +        Upon exiting a context block with this class, we want to ensure that the instance of the
> +        application is explicitly closed and properly cleaned up using its close method. Note that
> +        because this method returns :data:`None` if an exception was raised within the block, it is
> +        not handled and will be re-raised after the application is closed.
> +
> +        The desired behavior is to close the application regardless of the reason for exiting the
> +        context and then recreate that reason afterwards. All method arguments are ignored for
> +        this reason.
> +        """
> +        self.close()
> diff --git a/dts/framework/remote_session/python_shell.py b/dts/framework/remote_session/python_shell.py
> index 9d4abab12c..17e6c2559d 100644
> --- a/dts/framework/remote_session/python_shell.py
> +++ b/dts/framework/remote_session/python_shell.py
> @@ -29,3 +29,7 @@ class PythonShell(InteractiveShell):
>
>      #: The Python executable.
>      path: ClassVar[PurePath] = PurePath("python3")
> +
> +    def close(self):
> +        """Close Python shell."""
> +        return super().close()
> diff --git a/dts/framework/remote_session/shell_pool.py b/dts/framework/remote_session/shell_pool.py
> index 173aa8fd36..da956950d5 100644
> --- a/dts/framework/remote_session/shell_pool.py
> +++ b/dts/framework/remote_session/shell_pool.py
> @@ -90,7 +90,7 @@ def terminate_current_pool(self):
>          for shell in self._pools.pop():
>              self._logger.debug(f"Closing shell {shell} in shell pool level {current_pool_level}.")
>              try:
> -                shell._close()
> +                shell.close()
>              except Exception as e:
>                  self._logger.error(f"An exception has occurred while closing shell {shell}:")
>                  self._logger.exception(e)
> diff --git a/dts/framework/remote_session/single_active_interactive_shell.py b/dts/framework/remote_session/single_active_interactive_shell.py
> deleted file mode 100644
> index 2257b6156b..0000000000
> --- a/dts/framework/remote_session/single_active_interactive_shell.py
> +++ /dev/null
> @@ -1,275 +0,0 @@
> -# SPDX-License-Identifier: BSD-3-Clause
> -# Copyright(c) 2024 University of New Hampshire
> -
> -"""Common functionality for interactive shell handling.
> -
> -The base class, :class:`SingleActiveInteractiveShell`, is meant to be extended by subclasses that
> -contain functionality specific to that shell type. These subclasses will often modify things like
> -the prompt to expect or the arguments to pass into the application, but still utilize
> -the same method for sending a command and collecting output. How this output is handled however
> -is often application specific. If an application needs elevated privileges to start it is expected
> -that the method for gaining those privileges is provided when initializing the class.
> -
> -This class is designed for applications like primary applications in DPDK where only one instance
> -of the application can be running at a given time and, for this reason, is managed using a context
> -manager. This context manager starts the application when you enter the context and cleans up the
> -application when you exit. Using a context manager for this is useful since it allows us to ensure
> -the application is cleaned up as soon as you leave the block regardless of the reason.
> -
> -The :option:`--timeout` command line argument and the :envvar:`DTS_TIMEOUT`
> -environment variable configure the timeout of getting the output from command execution.
> -"""
> -
> -from abc import ABC
> -from pathlib import PurePath
> -from typing import ClassVar
> -
> -from paramiko import Channel, channel
> -from typing_extensions import Self
> -
> -from framework.exception import (
> -    InteractiveCommandExecutionError,
> -    InteractiveSSHSessionDeadError,
> -    InteractiveSSHTimeoutError,
> -)
> -from framework.logger import DTSLogger, get_dts_logger
> -from framework.params import Params
> -from framework.settings import SETTINGS
> -from framework.testbed_model.node import Node
> -from framework.utils import MultiInheritanceBaseClass
> -
> -
> -class SingleActiveInteractiveShell(MultiInheritanceBaseClass, ABC):
> -    """The base class for managing interactive shells.
> -
> -    This class shouldn't be instantiated directly, but instead be extended. It contains
> -    methods for starting interactive shells as well as sending commands to these shells
> -    and collecting input until reaching a certain prompt. All interactive applications
> -    will use the same SSH connection, but each will create their own channel on that
> -    session.
> -
> -    Interactive shells are started and stopped using a context manager. This allows for the start
> -    and cleanup of the application to happen at predictable times regardless of exceptions or
> -    interrupts.
> -
> -    Attributes:
> -        is_alive: :data:`True` if the application has started successfully, :data:`False`
> -            otherwise.
> -    """
> -
> -    _node: Node
> -    _stdin: channel.ChannelStdinFile
> -    _stdout: channel.ChannelFile
> -    _ssh_channel: Channel
> -    _logger: DTSLogger
> -    _timeout: float
> -    _app_params: Params
> -    _privileged: bool
> -    _real_path: PurePath
> -
> -    #: The number of times to try starting the application before considering it a failure.
> -    _init_attempts: ClassVar[int] = 5
> -
> -    #: Prompt to expect at the end of output when sending a command.
> -    #: This is often overridden by subclasses.
> -    _default_prompt: ClassVar[str] = ""
> -
> -    #: Extra characters to add to the end of every command
> -    #: before sending them. This is often overridden by subclasses and is
> -    #: most commonly an additional newline character. This additional newline
> -    #: character is used to force the line that is currently awaiting input
> -    #: into the stdout buffer so that it can be consumed and checked against
> -    #: the expected prompt.
> -    _command_extra_chars: ClassVar[str] = ""
> -
> -    #: Path to the executable to start the interactive application.
> -    path: ClassVar[PurePath]
> -
> -    is_alive: bool = False
> -
> -    def __init__(
> -        self,
> -        node: Node,
> -        name: str | None = None,
> -        privileged: bool = False,
> -        path: PurePath | None = None,
> -        app_params: Params = Params(),
> -        **kwargs,
> -    ) -> None:
> -        """Create an SSH channel during initialization.
> -
> -        Additional keyword arguments can be passed through `kwargs` if needed for fulfilling other
> -        constructors in the case of multiple inheritance.
> -
> -        Args:
> -            node: The node on which to run start the interactive shell.
> -            name: Name for the interactive shell to use for logging. This name will be appended to
> -                the name of the underlying node which it is running on.
> -            privileged: Enables the shell to run as superuser.
> -            path: Path to the executable. If :data:`None`, then the class' path attribute is used.
> -            app_params: The command line parameters to be passed to the application on startup.
> -            **kwargs: Any additional arguments if any.
> -        """
> -        self._node = node
> -        if name is None:
> -            name = type(self).__name__
> -        self._logger = get_dts_logger(f"{node.name}.{name}")
> -        self._app_params = app_params
> -        self._privileged = privileged
> -        self._timeout = SETTINGS.timeout
> -        # Ensure path is properly formatted for the host
> -        self._update_real_path(path or self.path)
> -        super().__init__(**kwargs)
> -
> -    def _setup_ssh_channel(self):
> -        self._ssh_channel = self._node.main_session.interactive_session.session.invoke_shell()
> -        self._stdin = self._ssh_channel.makefile_stdin("w")
> -        self._stdout = self._ssh_channel.makefile("r")
> -        self._ssh_channel.settimeout(self._timeout)
> -        self._ssh_channel.set_combine_stderr(True)  # combines stdout and stderr streams
> -
> -    def _make_start_command(self) -> str:
> -        """Makes the command that starts the interactive shell."""
> -        start_command = f"{self._real_path} {self._app_params or ''}"
> -        if self._privileged:
> -            start_command = self._node.main_session._get_privileged_command(start_command)
> -        return start_command
> -
> -    def _start_application(self, prompt: str | None = None) -> None:
> -        """Starts a new interactive application based on the path to the app.
> -
> -        This method is often overridden by subclasses as their process for starting may look
> -        different. Initialization of the shell on the host can be retried up to
> -        `self._init_attempts` - 1 times. This is done because some DPDK applications need slightly
> -        more time after exiting their script to clean up EAL before others can start.
> -
> -        Args:
> -            prompt: When starting up the application, expect this string at the end of stdout when
> -                the application is ready. If :data:`None`, the class' default prompt will be used.
> -
> -        Raises:
> -            InteractiveCommandExecutionError: If the application fails to start within the allotted
> -                number of retries.
> -        """
> -        self._setup_ssh_channel()
> -        self._ssh_channel.settimeout(5)
> -        start_command = self._make_start_command()
> -        self.is_alive = True
> -        for attempt in range(self._init_attempts):
> -            try:
> -                self.send_command(start_command, prompt)
> -                break
> -            except InteractiveSSHTimeoutError:
> -                self._logger.info(
> -                    f"Interactive shell failed to start (attempt {attempt+1} out of "
> -                    f"{self._init_attempts})"
> -                )
> -        else:
> -            self._ssh_channel.settimeout(self._timeout)
> -            self.is_alive = False  # update state on failure to start
> -            raise InteractiveCommandExecutionError("Failed to start application.")
> -        self._ssh_channel.settimeout(self._timeout)
> -
> -    def send_command(
> -        self, command: str, prompt: str | None = None, skip_first_line: bool = False
> -    ) -> str:
> -        """Send `command` and get all output before the expected ending string.
> -
> -        Lines that expect input are not included in the stdout buffer, so they cannot
> -        be used for expect.
> -
> -        Example:
> -            If you were prompted to log into something with a username and password,
> -            you cannot expect ``username:`` because it won't yet be in the stdout buffer.
> -            A workaround for this could be consuming an extra newline character to force
> -            the current `prompt` into the stdout buffer.
> -
> -        Args:
> -            command: The command to send.
> -            prompt: After sending the command, `send_command` will be expecting this string.
> -                If :data:`None`, will use the class's default prompt.
> -            skip_first_line: Skip the first line when capturing the output.
> -
> -        Returns:
> -            All output in the buffer before expected string.
> -
> -        Raises:
> -            InteractiveCommandExecutionError: If attempting to send a command to a shell that is
> -                not currently running.
> -            InteractiveSSHSessionDeadError: The session died while executing the command.
> -            InteractiveSSHTimeoutError: If command was sent but prompt could not be found in
> -                the output before the timeout.
> -        """
> -        if not self.is_alive:
> -            raise InteractiveCommandExecutionError(
> -                f"Cannot send command {command} to application because the shell is not running."
> -            )
> -        self._logger.info(f"Sending: '{command}'")
> -        if prompt is None:
> -            prompt = self._default_prompt
> -        out: str = ""
> -        try:
> -            self._stdin.write(f"{command}{self._command_extra_chars}\n")
> -            self._stdin.flush()
> -            for line in self._stdout:
> -                if skip_first_line:
> -                    skip_first_line = False
> -                    continue
> -                if line.rstrip().endswith(prompt):
> -                    break
> -                out += line
> -        except TimeoutError as e:
> -            self._logger.exception(e)
> -            self._logger.debug(
> -                f"Prompt ({prompt}) was not found in output from command before timeout."
> -            )
> -            raise InteractiveSSHTimeoutError(command) from e
> -        except OSError as e:
> -            self._logger.exception(e)
> -            raise InteractiveSSHSessionDeadError(
> -                self._node.main_session.interactive_session.hostname
> -            ) from e
> -        finally:
> -            self._logger.debug(f"Got output: {out}")
> -        return out
> -
> -    def _close(self) -> None:
> -        try:
> -            # Ensure the primary application has terminated via readiness of 'stdout'.
> -            if self._ssh_channel.recv_ready():
> -                self._ssh_channel.recv(1)  # 'Waits' for a single byte to enter 'stdout' buffer.
> -        except TimeoutError as e:
> -            self._logger.exception(e)
> -            self._logger.debug("Application failed to exit before set timeout.")
> -            raise InteractiveSSHTimeoutError("Application 'exit' command") from e
> -        self._ssh_channel.close()
> -
> -    def _update_real_path(self, path: PurePath) -> None:
> -        """Updates the interactive shell's real path used at command line."""
> -        self._real_path = self._node.main_session.join_remote_path(path)
> -
> -    def __enter__(self) -> Self:
> -        """Enter the context block.
> -
> -        Upon entering a context block with this class, the desired behavior is to create the
> -        channel for the application to use, and then start the application.
> -
> -        Returns:
> -            Reference to the object for the application after it has been started.
> -        """
> -        self._start_application()
> -        return self
> -
> -    def __exit__(self, *_) -> None:
> -        """Exit the context block.
> -
> -        Upon exiting a context block with this class, we want to ensure that the instance of the
> -        application is explicitly closed and properly cleaned up using its close method. Note that
> -        because this method returns :data:`None` if an exception was raised within the block, it is
> -        not handled and will be re-raised after the application is closed.
> -
> -        The desired behavior is to close the application regardless of the reason for exiting the
> -        context and then recreate that reason afterwards. All method arguments are ignored for
> -        this reason.
> -        """
> -        self._close()
> diff --git a/dts/framework/remote_session/testpmd_shell.py b/dts/framework/remote_session/testpmd_shell.py
> index db1bfaa9d1..b83b0c82a0 100644
> --- a/dts/framework/remote_session/testpmd_shell.py
> +++ b/dts/framework/remote_session/testpmd_shell.py
> @@ -2312,11 +2312,11 @@ def rx_vxlan(self, vxlan_id: int, port_id: int, enable: bool, verify: bool = Tru
>                  self._logger.debug(f"Failed to set VXLAN:\n{vxlan_output}")
>                  raise InteractiveCommandExecutionError(f"Failed to set VXLAN:\n{vxlan_output}")
>
> -    def _close(self) -> None:
> +    def close(self) -> None:
>          """Overrides :meth:`~.interactive_shell.close`."""
>          self.stop()
>          self.send_command("quit", "Bye...")
> -        return super()._close()
> +        return super().close()
>
>      """
>      ====== Capability retrieval methods ======
> --
> 2.43.0
>