On Fri, Dec 1, 2023 at 7:18 PM Jeremy Spewock <jspew...@iol.unh.edu> wrote:
>
>
>
> On Thu, Nov 23, 2023 at 10:14 AM Juraj Linkeš <juraj.lin...@pantheon.tech>
> wrote:
>>
>> Format according to the Google format and PEP257, with slight
>> deviations.
>>
>> Signed-off-by: Juraj Linkeš <juraj.lin...@pantheon.tech>
>> ---
>> .../testbed_model/traffic_generator/scapy.py | 91 +++++++++++--------
>> 1 file changed, 54 insertions(+), 37 deletions(-)
>>
>> diff --git a/dts/framework/testbed_model/traffic_generator/scapy.py
>> b/dts/framework/testbed_model/traffic_generator/scapy.py
>> index c88cf28369..30ea3914ee 100644
>> --- a/dts/framework/testbed_model/traffic_generator/scapy.py
>> +++ b/dts/framework/testbed_model/traffic_generator/scapy.py
>> @@ -2,14 +2,15 @@
>> # Copyright(c) 2022 University of New Hampshire
>> # Copyright(c) 2023 PANTHEON.tech s.r.o.
>>
>> -"""Scapy traffic generator.
>> +"""The Scapy traffic generator.
>>
>> -Traffic generator used for functional testing, implemented using the Scapy
>> library.
>> +A traffic generator used for functional testing, implemented with
>> +`the Scapy library <https://scapy.readthedocs.io/en/latest/>`_.
>> The traffic generator uses an XML-RPC server to run Scapy on the remote TG
>> node.
>>
>> -The XML-RPC server runs in an interactive remote SSH session running Python
>> console,
>> -where we start the server. The communication with the server is facilitated
>> with
>> -a local server proxy.
>> +The traffic generator uses the :mod:`xmlrpc.server` module to run an
>> XML-RPC server
>> +in an interactive remote Python SSH session. The communication with the
>> server is facilitated
>> +with a local server proxy from the :mod:`xmlrpc.client` module.
>> """
>>
>> import inspect
>> @@ -69,20 +70,20 @@ def scapy_send_packets_and_capture(
>> recv_iface: str,
>> duration: float,
>> ) -> list[bytes]:
>> - """RPC function to send and capture packets.
>> + """The RPC function to send and capture packets.
>>
>> - The function is meant to be executed on the remote TG node.
>> + The function is meant to be executed on the remote TG node via the
>> server proxy.
>>
>
> Should this maybe be "This function is meant" instead? I'm not completely
> sure if it should be, I feel like it might be able to go either way.
>
There is something to this. It's a bit more explicit and as such less
confusing which feels better, so I'll change it in all three
instances.
>>
>> Args:
>> xmlrpc_packets: The packets to send. These need to be converted to
>> - xmlrpc.client.Binary before sending to the remote server.
>> + :class:`~xmlrpc.client.Binary` objects before sending to the
>> remote server.
>> send_iface: The logical name of the egress interface.
>> recv_iface: The logical name of the ingress interface.
>> duration: Capture for this amount of time, in seconds.
>>
>> Returns:
>> A list of bytes. Each item in the list represents one packet, which
>> needs
>> - to be converted back upon transfer from the remote node.
>> + to be converted back upon transfer from the remote node.
>> """
>> scapy_packets = [scapy.all.Packet(packet.data) for packet in
>> xmlrpc_packets]
>> sniffer = scapy.all.AsyncSniffer(
>> @@ -96,19 +97,15 @@ def scapy_send_packets_and_capture(
>>
>>
>> def scapy_send_packets(xmlrpc_packets: list[xmlrpc.client.Binary],
>> send_iface: str) -> None:
>> - """RPC function to send packets.
>> + """The RPC function to send packets.
>>
>> - The function is meant to be executed on the remote TG node.
>> - It doesn't return anything, only sends packets.
>> + The function is meant to be executed on the remote TG node via the
>> server proxy.
>
>
> Same thing here. I don't think it matters that much since you refer to it as
> being "the RPC function" for sending packets, but it feels like you are
> referring instead to this specific function on this line.
>
>>
>> + It only sends `xmlrpc_packets`, without capturing them.
>>
>> Args:
>> xmlrpc_packets: The packets to send. These need to be converted to
>> - xmlrpc.client.Binary before sending to the remote server.
>> + :class:`~xmlrpc.client.Binary` objects before sending to the
>> remote server.
>> send_iface: The logical name of the egress interface.
>> -
>> - Returns:
>> - A list of bytes. Each item in the list represents one packet, which
>> needs
>> - to be converted back upon transfer from the remote node.
>> """
>> scapy_packets = [scapy.all.Packet(packet.data) for packet in
>> xmlrpc_packets]
>> scapy.all.sendp(scapy_packets, iface=send_iface, realtime=True,
>> verbose=True)
>> @@ -128,11 +125,19 @@ def scapy_send_packets(xmlrpc_packets:
>> list[xmlrpc.client.Binary], send_iface: s
>>
>>
>> class QuittableXMLRPCServer(SimpleXMLRPCServer):
>> - """Basic XML-RPC server that may be extended
>> - by functions serializable by the marshal module.
>> + """Basic XML-RPC server.
>> +
>> + The server may be augmented by functions serializable by the
>> :mod:`marshal` module.
>> """
>>
>> def __init__(self, *args, **kwargs):
>> + """Extend the XML-RPC server initialization.
>> +
>> + Args:
>> + args: The positional arguments that will be passed to the
>> superclass's constructor.
>> + kwargs: The keyword arguments that will be passed to the
>> superclass's constructor.
>> + The `allow_none` argument will be set to :data:`True`.
>> + """
>> kwargs["allow_none"] = True
>> super().__init__(*args, **kwargs)
>> self.register_introspection_functions()
>> @@ -140,13 +145,12 @@ def __init__(self, *args, **kwargs):
>> self.register_function(self.add_rpc_function)
>>
>> def quit(self) -> None:
>> + """Quit the server."""
>> self._BaseServer__shutdown_request = True
>> return None
>>
>> def add_rpc_function(self, name: str, function_bytes:
>> xmlrpc.client.Binary) -> None:
>> - """Add a function to the server.
>> -
>> - This is meant to be executed remotely.
>> + """Add a function to the server from the local server proxy.
>>
>> Args:
>> name: The name of the function.
>> @@ -157,6 +161,11 @@ def add_rpc_function(self, name: str, function_bytes:
>> xmlrpc.client.Binary) -> N
>> self.register_function(function)
>>
>> def serve_forever(self, poll_interval: float = 0.5) -> None:
>> + """Extend the superclass method with an additional print.
>> +
>> + Once executed in the local server proxy, the print gives us a clear
>> string to expect
>> + when starting the server. The print means the function was executed
>> on the XML-RPC server.
>> + """
>> print("XMLRPC OK")
>> super().serve_forever(poll_interval)
>>
>> @@ -164,19 +173,12 @@ def serve_forever(self, poll_interval: float = 0.5) ->
>> None:
>> class ScapyTrafficGenerator(CapturingTrafficGenerator):
>> """Provides access to scapy functions via an RPC interface.
>>
>> - The traffic generator first starts an XML-RPC on the remote TG node.
>> - Then it populates the server with functions which use the Scapy library
>> - to send/receive traffic.
>> -
>> - Any packets sent to the remote server are first converted to bytes.
>> - They are received as xmlrpc.client.Binary objects on the server side.
>> - When the server sends the packets back, they are also received as
>> - xmlrpc.client.Binary object on the client side, are converted back to
>> Scapy
>> - packets and only then returned from the methods.
>> + The class extends the base with remote execution of scapy functions.
>
>
> Same thing here if the above end up getting changed.
>
>>
>>
>> - Arguments:
>> - tg_node: The node where the traffic generator resides.
>> - config: The user configuration of the traffic generator.
>> + Any packets sent to the remote server are first converted to bytes.
>> They are received as
>> + :class:`~xmlrpc.client.Binary` objects on the server side. When the
>> server sends the packets
>> + back, they are also received as :class:`~xmlrpc.client.Binary` objects
>> on the client side, are
>> + converted back to :class:`~scapy.packet.Packet` objects and only then
>> returned from the methods.
>>
>> Attributes:
>> session: The exclusive interactive remote session created by the
>> Scapy
>> @@ -190,6 +192,22 @@ class ScapyTrafficGenerator(CapturingTrafficGenerator):
>> _config: ScapyTrafficGeneratorConfig
>>
>> def __init__(self, tg_node: Node, config: ScapyTrafficGeneratorConfig):
>> + """Extend the constructor with Scapy TG specifics.
>> +
>> + The traffic generator first starts an XML-RPC on the remote
>> `tg_node`.
>> + Then it populates the server with functions which use the Scapy
>> library
>> + to send/receive traffic:
>> +
>> + * :func:`scapy_send_packets_and_capture`
>> + * :func:`scapy_send_packets`
>> +
>> + To enable verbose logging from the xmlrpc client, use the
>> :option:`--verbose`
>> + command line argument or the :envvar:`DTS_VERBOSE` environment
>> variable.
>> +
>> + Args:
>> + tg_node: The node where the traffic generator resides.
>> + config: The traffic generator's test run configuration.
>> + """
>> super().__init__(tg_node, config)
>>
>> assert (
>> @@ -231,10 +249,8 @@ def _start_xmlrpc_server_in_remote_python(self,
>> listen_port: int) -> None:
>> # or class, so strip all lines containing only whitespace
>> src = "\n".join([line for line in src.splitlines() if not
>> line.isspace() and line != ""])
>>
>> - spacing = "\n" * 4
>> -
>> # execute it in the python terminal
>> - self.session.send_command(spacing + src + spacing)
>> + self.session.send_command(src + "\n")
>> self.session.send_command(
>> f"server = QuittableXMLRPCServer(('0.0.0.0',
>> {listen_port}));server.serve_forever()",
>> "XMLRPC OK",
>> @@ -267,6 +283,7 @@ def _send_packets_and_capture(
>> return scapy_packets
>>
>> def close(self) -> None:
>> + """Close the traffic generator."""
>> try:
>> self.rpc_server_proxy.quit()
>> except ConnectionRefusedError:
>> --
>> 2.34.1
>>
