[5/6] dts: add statefulness to InteractiveShell
Checks
Commit Message
The InteractiveShell class can be started in privileged mode, but this
is not saved for reference to the tests developer. Moreover, originally
a command timeout could only be set at initialisation, this can now be
amended and reset back as needed.
Signed-off-by: Luca Vizzarro <luca.vizzarro@arm.com>
Reviewed-by: Jack Bond-Preston <jack.bond-preston@arm.com>
Reviewed-by: Honnappa Nagarahalli <honnappa.nagarahalli@arm.com>
---
.../remote_session/interactive_shell.py | 18 +++++++++++++++++-
1 file changed, 17 insertions(+), 1 deletion(-)
Comments
On Tue, Mar 26, 2024 at 3:04 PM Luca Vizzarro <luca.vizzarro@arm.com> wrote:
<snip>
> diff --git a/dts/framework/remote_session/interactive_shell.py b/dts/framework/remote_session/interactive_shell.py
> index a2c7b30d9f..5d80061e8d 100644
> --- a/dts/framework/remote_session/interactive_shell.py
> +++ b/dts/framework/remote_session/interactive_shell.py
> @@ -41,8 +41,10 @@ class InteractiveShell(ABC):
> _stdout: channel.ChannelFile
> _ssh_channel: Channel
> _logger: DTSLogger
> + __default_timeout: float
Only single underscores are used for other private variables, probably
better to keep that consistent with this one.
> _timeout: float
> _app_args: Params | None
> + _is_privileged: bool = False
<snip>
> 2.34.1
>
I have a general question. What are these changes for? Do you
anticipate us needing this in the future? Wouldn't it be better to add
it only when we need it?
On Thu, Mar 28, 2024 at 5:48 PM Jeremy Spewock <jspewock@iol.unh.edu> wrote:
>
> On Tue, Mar 26, 2024 at 3:04 PM Luca Vizzarro <luca.vizzarro@arm.com> wrote:
> <snip>
> > diff --git a/dts/framework/remote_session/interactive_shell.py b/dts/framework/remote_session/interactive_shell.py
> > index a2c7b30d9f..5d80061e8d 100644
> > --- a/dts/framework/remote_session/interactive_shell.py
> > +++ b/dts/framework/remote_session/interactive_shell.py
> > @@ -41,8 +41,10 @@ class InteractiveShell(ABC):
> > _stdout: channel.ChannelFile
> > _ssh_channel: Channel
> > _logger: DTSLogger
> > + __default_timeout: float
>
> Only single underscores are used for other private variables, probably
> better to keep that consistent with this one.
>
I agree, I don't see a reason for the double underscore.
> > _timeout: float
> > _app_args: Params | None
> > + _is_privileged: bool = False
> <snip>
> > 2.34.1
> >
On 10/04/2024 07:53, Juraj Linkeš wrote:
> I have a general question. What are these changes for? Do you
> anticipate us needing this in the future? Wouldn't it be better to add
> it only when we need it?
It's been sometime since we raised this task internally. This patch and
the next one arise from some survey done on old DTS test cases.
Unfortunately, I can't pinpoint.
Specifically for this patch though, the timeout bit is useful in
conjunction with the related change in the next. Instead of giving an
optional timeout argument to all the commands where we may want to
change it, aren't we better off with providing a facility to temporarily
change this for the current scope?
>
> On Thu, Mar 28, 2024 at 5:48 PM Jeremy Spewock <jspewock@iol.unh.edu> wrote:
>>
>> On Tue, Mar 26, 2024 at 3:04 PM Luca Vizzarro <luca.vizzarro@arm.com> wrote:
>> <snip>
>>> diff --git a/dts/framework/remote_session/interactive_shell.py b/dts/framework/remote_session/interactive_shell.py
>>> index a2c7b30d9f..5d80061e8d 100644
>>> --- a/dts/framework/remote_session/interactive_shell.py
>>> +++ b/dts/framework/remote_session/interactive_shell.py
>>> @@ -41,8 +41,10 @@ class InteractiveShell(ABC):
>>> _stdout: channel.ChannelFile
>>> _ssh_channel: Channel
>>> _logger: DTSLogger
>>> + __default_timeout: float
>>
>> Only single underscores are used for other private variables, probably
>> better to keep that consistent with this one.
>>
>
> I agree, I don't see a reason for the double underscore.
Ack.
>
>>> _timeout: float
>>> _app_args: Params | None
>>> + _is_privileged: bool = False
>> <snip>
>>> 2.34.1
>>>
On Wed, Apr 10, 2024 at 1:27 PM Luca Vizzarro <Luca.Vizzarro@arm.com> wrote:
>
> On 10/04/2024 07:53, Juraj Linkeš wrote:
> > I have a general question. What are these changes for? Do you
> > anticipate us needing this in the future? Wouldn't it be better to add
> > it only when we need it?
>
> It's been sometime since we raised this task internally. This patch and
> the next one arise from some survey done on old DTS test cases.
> Unfortunately, I can't pinpoint.
>
> Specifically for this patch though, the timeout bit is useful in
> conjunction with the related change in the next. Instead of giving an
> optional timeout argument to all the commands where we may want to
> change it, aren't we better off with providing a facility to temporarily
> change this for the current scope?
>
This is a good question. If the scope is just one command, then no. If
it's more than one, then maybe yes. I don't know which is better.
We should also consider that this would introduce a difference in API
between the interactive and non-interactive sessions. Do we want to do
this there as well?
Also, maybe set_timeout should be a property or we could just make
_timeout public.
And is_privileged should just be privileged, as it's a property (which
shouldn't contain a verb; if it was a method it would be a good name).
> >
> > On Thu, Mar 28, 2024 at 5:48 PM Jeremy Spewock <jspewock@iol.unh.edu> wrote:
> >>
> >> On Tue, Mar 26, 2024 at 3:04 PM Luca Vizzarro <luca.vizzarro@arm.com> wrote:
> >> <snip>
> >>> diff --git a/dts/framework/remote_session/interactive_shell.py b/dts/framework/remote_session/interactive_shell.py
> >>> index a2c7b30d9f..5d80061e8d 100644
> >>> --- a/dts/framework/remote_session/interactive_shell.py
> >>> +++ b/dts/framework/remote_session/interactive_shell.py
> >>> @@ -41,8 +41,10 @@ class InteractiveShell(ABC):
> >>> _stdout: channel.ChannelFile
> >>> _ssh_channel: Channel
> >>> _logger: DTSLogger
> >>> + __default_timeout: float
> >>
> >> Only single underscores are used for other private variables, probably
> >> better to keep that consistent with this one.
> >>
> >
> > I agree, I don't see a reason for the double underscore.
>
> Ack.
>
> >
> >>> _timeout: float
> >>> _app_args: Params | None
> >>> + _is_privileged: bool = False
> >> <snip>
> >>> 2.34.1
> >>>
>
On 10/04/2024 14:35, Juraj Linkeš wrote:
> We should also consider that this would introduce a difference in API
> between the interactive and non-interactive sessions. Do we want to do
> this there as well?
Could definitely add it there as well. You are referring to
RemoteSession I presume, right?
On Wed, Apr 10, 2024 at 4:07 PM Luca Vizzarro <Luca.Vizzarro@arm.com> wrote:
>
> On 10/04/2024 14:35, Juraj Linkeš wrote:
> > We should also consider that this would introduce a difference in API
> > between the interactive and non-interactive sessions. Do we want to do
> > this there as well?
>
> Could definitely add it there as well. You are referring to
> RemoteSession I presume, right?
Yes.
On Wed, Apr 10, 2024 at 9:36 AM Juraj Linkeš <juraj.linkes@pantheon.tech> wrote:
>
> On Wed, Apr 10, 2024 at 1:27 PM Luca Vizzarro <Luca.Vizzarro@arm.com> wrote:
> >
> > On 10/04/2024 07:53, Juraj Linkeš wrote:
> > > I have a general question. What are these changes for? Do you
> > > anticipate us needing this in the future? Wouldn't it be better to add
> > > it only when we need it?
> >
> > It's been sometime since we raised this task internally. This patch and
> > the next one arise from some survey done on old DTS test cases.
> > Unfortunately, I can't pinpoint.
> >
> > Specifically for this patch though, the timeout bit is useful in
> > conjunction with the related change in the next. Instead of giving an
> > optional timeout argument to all the commands where we may want to
> > change it, aren't we better off with providing a facility to temporarily
> > change this for the current scope?
> >
>
> This is a good question. If the scope is just one command, then no. If
> it's more than one, then maybe yes. I don't know which is better.
>
> We should also consider that this would introduce a difference in API
> between the interactive and non-interactive sessions. Do we want to do
> this there as well?
I believe there already is a difference in this case since the
interactive shell doesn't support modification of timeout on a
per-command basis. This is mainly because the way interactive shells
handle timeouts is on a lower level than sending a command using
fabric. Currently the interactive shells are modifying the timeout on
the channel of the connection, whereas fabric supports a keyword
argument that can modify timeouts on a per-command basis.
Of course we could also change the interactive shell send_command to
modify the timeout of the shell, but something else to note here is
that changing the timeout of the channel of the connection is slightly
different than giving a timeout for a command. This is because when
you change the timeout of the channel you're setting the timeout for
read/write operations on that channel. So, if you send a command and
give a timeout of 5 seconds for example, as long as you are receiving
output from the shell at least every 5 seconds, the command actually
wouldn't ever timeout. If we want to make the interactive shell
support passing a timeout per command, I would recommend we do it in a
different way that is more representative of your *command* having a
timeout instead of the shell's channel having a timeout.
Waiting for the status of a link to be "up" in testpmd was an
exception where I did allow you to give a specific timeout for the
command and this is exactly for the reason above. I wanted to make
sure that the user was able to specify how long they wanted to wait
for this status to be what they expect as opposed to how long to wait
for getting output from the channel. This is not supported in any
other method of the interactive shell.
>
> Also, maybe set_timeout should be a property or we could just make
> _timeout public.
> And is_privileged should just be privileged, as it's a property (which
> shouldn't contain a verb; if it was a method it would be a good name).
<snip>
> >
@@ -41,8 +41,10 @@ class InteractiveShell(ABC):
_stdout: channel.ChannelFile
_ssh_channel: Channel
_logger: DTSLogger
+ __default_timeout: float
_timeout: float
_app_args: Params | None
+ _is_privileged: bool = False
#: Prompt to expect at the end of output when sending a command.
#: This is often overridden by subclasses.
@@ -88,7 +90,7 @@ def __init__(
self._ssh_channel.settimeout(timeout)
self._ssh_channel.set_combine_stderr(True) # combines stdout and stderr streams
self._logger = logger
- self._timeout = timeout
+ self._timeout = self.__default_timeout = timeout
self._app_args = app_args
self._start_application(get_privileged_command)
@@ -105,6 +107,7 @@ def _start_application(self, get_privileged_command: Callable[[str], str] | None
start_command = f"{self.path} {self._app_args or ''}"
if get_privileged_command is not None:
start_command = get_privileged_command(start_command)
+ self._is_privileged = True
self.send_command(start_command)
def send_command(self, command: str, prompt: str | None = None) -> str:
@@ -150,3 +153,16 @@ def close(self) -> None:
def __del__(self) -> None:
"""Make sure the session is properly closed before deleting the object."""
self.close()
+
+ @property
+ def is_privileged(self) -> bool:
+ """Property specifying if the interactive shell is running in privileged mode."""
+ return self._is_privileged
+
+ def set_timeout(self, timeout: float):
+ """Set the timeout to use with the next commands."""
+ self._timeout = timeout
+
+ def reset_timeout(self):
+ """Reset the timeout to the default setting."""
+ self._timeout = self.__default_timeout