[PATCH v7 17/21] dts: node docstring update

[Yoan Picchi]

On 11/15/23 13:09, Juraj Linkeš wrote:
> Format according to the Google format and PEP257, with slight
> deviations.
> 
> Signed-off-by: Juraj Linkeš <juraj.linkes at pantheon.tech>
> ---
>   dts/framework/testbed_model/node.py | 191 +++++++++++++++++++---------
>   1 file changed, 131 insertions(+), 60 deletions(-)
> 
> diff --git a/dts/framework/testbed_model/node.py b/dts/framework/testbed_model/node.py
> index fa5b143cdd..f93b4acecd 100644
> --- a/dts/framework/testbed_model/node.py
> +++ b/dts/framework/testbed_model/node.py
> @@ -3,8 +3,13 @@
>   # Copyright(c) 2022-2023 PANTHEON.tech s.r.o.
>   # Copyright(c) 2022-2023 University of New Hampshire
>   
> -"""
> -A node is a generic host that DTS connects to and manages.
> +"""Common functionality for node management.
> +
> +A node is any host/server DTS connects to.
> +
> +The base class, :class:`Node`, provides functionality common to all nodes and is supposed
> +to be extended by subclasses with functionality specific to each node type.

functionality -> functionalities

> +The decorator :func:`Node.skip_setup` can be used without subclassing.
>   """
>   
>   from abc import ABC
> @@ -35,10 +40,22 @@
>   
>   
>   class Node(ABC):
> -    """
> -    Basic class for node management. This class implements methods that
> -    manage a node, such as information gathering (of CPU/PCI/NIC) and
> -    environment setup.
> +    """The base class for node management.
> +
> +    It shouldn't be instantiated, but rather subclassed.
> +    It implements common methods to manage any node:
> +
> +        * Connection to the node,
> +        * Hugepages setup.
> +
> +    Attributes:
> +        main_session: The primary OS-aware remote session used to communicate with the node.
> +        config: The node configuration.
> +        name: The name of the node.
> +        lcores: The list of logical cores that DTS can use on the node.
> +            It's derived from logical cores present on the node and the test run configuration.
> +        ports: The ports of this node specified in the test run configuration.
> +        virtual_devices: The virtual devices used on the node.
>       """
>   
>       main_session: OSSession
> @@ -52,6 +69,17 @@ class Node(ABC):
>       virtual_devices: list[VirtualDevice]
>   
>       def __init__(self, node_config: NodeConfiguration):
> +        """Connect to the node and gather info during initialization.
> +
> +        Extra gathered information:
> +
> +        * The list of available logical CPUs. This is then filtered by
> +          the ``lcores`` configuration in the YAML test run configuration file,
> +        * Information about ports from the YAML test run configuration file.
> +
> +        Args:
> +            node_config: The node's test run configuration.
> +        """
>           self.config = node_config
>           self.name = node_config.name
>           self._logger = getLogger(self.name)
> @@ -60,7 +88,7 @@ def __init__(self, node_config: NodeConfiguration):
>           self._logger.info(f"Connected to node: {self.name}")
>   
>           self._get_remote_cpus()
> -        # filter the node lcores according to user config
> +        # filter the node lcores according to the test run configuration
>           self.lcores = LogicalCoreListFilter(
>               self.lcores, LogicalCoreList(self.config.lcores)
>           ).filter()
> @@ -76,9 +104,14 @@ def _init_ports(self) -> None:
>               self.configure_port_state(port)
>   
>       def set_up_execution(self, execution_config: ExecutionConfiguration) -> None:
> -        """
> -        Perform the execution setup that will be done for each execution
> -        this node is part of.
> +        """Execution setup steps.
> +
> +        Configure hugepages and call :meth:`_set_up_execution` where
> +        the rest of the configuration steps (if any) are implemented.
> +
> +        Args:
> +            execution_config: The execution test run configuration according to which
> +                the setup steps will be taken.
>           """
>           self._setup_hugepages()
>           self._set_up_execution(execution_config)
> @@ -87,58 +120,74 @@ def set_up_execution(self, execution_config: ExecutionConfiguration) -> None:
>               self.virtual_devices.append(VirtualDevice(vdev))
>   
>       def _set_up_execution(self, execution_config: ExecutionConfiguration) -> None:
> -        """
> -        This method exists to be optionally overwritten by derived classes and
> -        is not decorated so that the derived class doesn't have to use the decorator.
> +        """Optional additional execution setup steps for subclasses.
> +
> +        Subclasses should override this if they need to add additional execution setup steps.
>           """
>   
>       def tear_down_execution(self) -> None:
> -        """
> -        Perform the execution teardown that will be done after each execution
> -        this node is part of concludes.
> +        """Execution teardown steps.
> +
> +        There are currently no common execution teardown steps common to all DTS node types.
>           """
>           self.virtual_devices = []
>           self._tear_down_execution()
>   
>       def _tear_down_execution(self) -> None:
> -        """
> -        This method exists to be optionally overwritten by derived classes and
> -        is not decorated so that the derived class doesn't have to use the decorator.
> +        """Optional additional execution teardown steps for subclasses.
> +
> +        Subclasses should override this if they need to add additional execution teardown steps.
>           """
>   
>       def set_up_build_target(
>           self, build_target_config: BuildTargetConfiguration
>       ) -> None:
> -        """
> -        Perform the build target setup that will be done for each build target
> -        tested on this node.
> +        """Build target setup steps.
> +
> +        There are currently no common build target setup steps common to all DTS node types.
> +
> +        Args:
> +            build_target_config: The build target test run configuration according to which
> +                the setup steps will be taken.
>           """
>           self._set_up_build_target(build_target_config)
>   
>       def _set_up_build_target(
>           self, build_target_config: BuildTargetConfiguration
>       ) -> None:
> -        """
> -        This method exists to be optionally overwritten by derived classes and
> -        is not decorated so that the derived class doesn't have to use the decorator.
> +        """Optional additional build target setup steps for subclasses.
> +
> +        Subclasses should override this if they need to add additional build target setup steps.
>           """
>   
>       def tear_down_build_target(self) -> None:
> -        """
> -        Perform the build target teardown that will be done after each build target
> -        tested on this node.
> +        """Build target teardown steps.
> +
> +        There are currently no common build target teardown steps common to all DTS node types.
>           """
>           self._tear_down_build_target()
>   
>       def _tear_down_build_target(self) -> None:
> -        """
> -        This method exists to be optionally overwritten by derived classes and
> -        is not decorated so that the derived class doesn't have to use the decorator.
> +        """Optional additional build target teardown steps for subclasses.
> +
> +        Subclasses should override this if they need to add additional build target teardown steps.
>           """
>   
>       def create_session(self, name: str) -> OSSession:
> -        """
> -        Create and return a new OSSession tailored to the remote OS.
> +        """Create and return a new OS-aware remote session.
> +
> +        The returned session won't be used by the node creating it. The session must be used by
> +        the caller. The session will be maintained for the entire lifecycle of the node object,
> +        at the end of which the session will be cleaned up automatically.
> +
> +        Note:
> +            Any number of these supplementary sessions may be created.
> +
> +        Args:
> +            name: The name of the session.
> +
> +        Returns:
> +            A new OS-aware remote session.
>           """
>           session_name = f"{self.name} {name}"
>           connection = create_session(
> @@ -156,19 +205,19 @@ def create_interactive_shell(
>           privileged: bool = False,
>           app_args: str = "",
>       ) -> InteractiveShellType:
> -        """Create a handler for an interactive session.
> +        """Factory for interactive session handlers.
>   
> -        Instantiate shell_cls according to the remote OS specifics.
> +        Instantiate `shell_cls` according to the remote OS specifics.
>   
>           Args:
>               shell_cls: The class of the shell.
> -            timeout: Timeout for reading output from the SSH channel. If you are
> -                reading from the buffer and don't receive any data within the timeout
> -                it will throw an error.
> +            timeout: Timeout for reading output from the SSH channel. If you are reading from
> +                the buffer and don't receive any data within the timeout it will throw an error.
>               privileged: Whether to run the shell with administrative privileges.
>               app_args: The arguments to be passed to the application.
> +
>           Returns:
> -            Instance of the desired interactive application.
> +            An instance of the desired interactive application shell.
>           """
>           if not shell_cls.dpdk_app:
>               shell_cls.path = self.main_session.join_remote_path(shell_cls.path)
> @@ -185,14 +234,22 @@ def filter_lcores(
>           filter_specifier: LogicalCoreCount | LogicalCoreList,
>           ascending: bool = True,
>       ) -> list[LogicalCore]:
> -        """
> -        Filter the LogicalCores found on the Node according to
> -        a LogicalCoreCount or a LogicalCoreList.
> +        """Filter the node's logical cores that DTS can use.
> +
> +        Logical cores that DTS can use are the ones that are present on the node, but filtered
> +        according to the test run configuration. The `filter_specifier` will filter cores from
> +        those logical cores.
> +
> +        Args:
> +            filter_specifier: Two different filters can be used, one that specifies the number
> +                of logical cores per core, cores per socket and the number of sockets,
> +                and another one that specifies a logical core list.
> +            ascending: If :data:`True`, use cores with the lowest numerical id first and continue
> +                in ascending order. If :data:`False`, start with the highest id and continue
> +                in descending order. This ordering affects which sockets to consider first as well.
>   
> -        If ascending is True, use cores with the lowest numerical id first
> -        and continue in ascending order. If False, start with the highest
> -        id and continue in descending order. This ordering affects which
> -        sockets to consider first as well.
> +        Returns:
> +            The filtered logical cores.
>           """
>           self._logger.debug(f"Filtering {filter_specifier} from {self.lcores}.")
>           return lcore_filter(
> @@ -202,17 +259,14 @@ def filter_lcores(
>           ).filter()
>   
>       def _get_remote_cpus(self) -> None:
> -        """
> -        Scan CPUs in the remote OS and store a list of LogicalCores.
> -        """
> +        """Scan CPUs in the remote OS and store a list of LogicalCores."""
>           self._logger.info("Getting CPU information.")
>           self.lcores = self.main_session.get_remote_cpus(self.config.use_first_core)
>   
>       def _setup_hugepages(self) -> None:
> -        """
> -        Setup hugepages on the Node. Different architectures can supply different
> -        amounts of memory for hugepages and numa-based hugepage allocation may need
> -        to be considered.
> +        """Setup hugepages on the node.
> +
> +        Configure the hugepages only if they're specified in the node's test run configuration.
>           """
>           if self.config.hugepages:
>               self.main_session.setup_hugepages(
> @@ -220,8 +274,11 @@ def _setup_hugepages(self) -> None:
>               )
>   
>       def configure_port_state(self, port: Port, enable: bool = True) -> None:
> -        """
> -        Enable/disable port.
> +        """Enable/disable `port`.
> +
> +        Args:
> +            port: The port to enable/disable.
> +            enable: :data:`True` to enable, :data:`False` to disable.
>           """
>           self.main_session.configure_port_state(port, enable)
>   
> @@ -231,15 +288,17 @@ def configure_port_ip_address(
>           port: Port,
>           delete: bool = False,
>       ) -> None:
> -        """
> -        Configure the IP address of a port on this node.
> +        """Add an IP address to `port` on this node.
> +
> +        Args:
> +            address: The IP address with mask in CIDR format. Can be either IPv4 or IPv6.
> +            port: The port to which to add the address.
> +            delete: If :data:`True`, will delete the address from the port instead of adding it.
>           """
>           self.main_session.configure_port_ip_address(address, port, delete)
>   
>       def close(self) -> None:
> -        """
> -        Close all connections and free other resources.
> -        """
> +        """Close all connections and free other resources."""
>           if self.main_session:
>               self.main_session.close()
>           for session in self._other_sessions:
> @@ -248,6 +307,11 @@ def close(self) -> None:
>   
>       @staticmethod
>       def skip_setup(func: Callable[..., Any]) -> Callable[..., Any]:
> +        """Skip the decorated function.
> +
> +        The :option:`--skip-setup` command line argument and the :envvar:`DTS_SKIP_SETUP`
> +        environment variable enable the decorator.
> +        """
>           if SETTINGS.skip_setup:
>               return lambda *args: None
>           else:
> @@ -257,6 +321,13 @@ def skip_setup(func: Callable[..., Any]) -> Callable[..., Any]:
>   def create_session(
>       node_config: NodeConfiguration, name: str, logger: DTSLOG
>   ) -> OSSession:
> +    """Factory for OS-aware sessions.
> +
> +    Args:
> +        node_config: The test run configuration of the node to connect to.
> +        name: The name of the session.
> +        logger: The logger instance this session will use.
> +    """
>       match node_config.os:
>           case OS.linux:
>               return LinuxSession(node_config, name, logger)