Supporting a new traffic filter type

The steps to add support for a new queuing discipline are:

1. Creation of a new Python class that inherits from TrafficFilter; the convention is to name such a class xxxFilter where xxx is the name of the filter

   xxxFilter.__init__() should expect as optional arguments:

   • the filter priority (an integer)

   • the Handle of the destination queuing class

   • the filter-specific parameters

2. The xxxFilter class must implement the filter_creation_args() method; this method should return the filter-specific tc(8) arguments for creating the filter

3. The xxxFilter class must implement the class method parse() to create a xxxFilter instance from the FilterOutput instance that is passed as an argument.

4. The xxxFilter class must be registered by invoking the TrafficFilterParser.register_filter() method

5. The xxxFilter class should implement the get_description() method

6. The xxxFilter class should implement the get_match_name() method

7. The xxxFilter class should implement getter methods for the filter-specific parameters

8. The xxxFilter class may implement setter methods for the filter-specific parameters

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TrafficFilter

class TrafficFilter(protocol: str, prio: Optional[int], filter_type: str, *, dest_class_handle: Optional[Handle] = None, filter_name: Optional[str] = None)

Generic filter class. It cannot be instantiated. It is subclassed based on filter type.

Parameters:

• protocol – protocol

• prio – optional filter priority (a number); defaults to -1

• filter_type – a string indicating one of the currently supported filter types: u32, fw

• dest_class_handle – Handle of class where this filter will direct traffic

• filter_name – user-friendly filter name

filter_creation_args() → List[str]

Returns a list of tc(8) arguments to create this filter

is_instantiated() → bool

Returns True if the filter is in the kernel

get_description() → str

Returns a string with detail info about the filter

get_match_name() → Optional[str]

Returns a string with the name that describes the traffic matched by the filter, or None.

This method should be defined in derived classes.

get_filter_type() → str

Returns the filter type

get_prio() → int

Returns the filter priority

set_prio(prio: int)

Set the filter priority.

Raises TcError if the filter is instantiated.

get_filter_name() → Optional[str]

Returns the filter name

set_filter_name(filter_name: str)

Set the filter name

get_dest_handle() → Optional[Handle]

Returns the Handle of the QClass where this filter will send traffic

set_dest_handle(handle: Handle)

Sets the handle of the class where this filter will send traffic.

Raises TcError if the filter is instantiated.

get_actions() → List[TrafficAction]

Returns the action list for this filter

add_action(action: TrafficAction) → None

Add a filter action