Files
netsec/env/lib/python3.12/site-packages/pyshark/packet/layers/base.py
2024-12-09 18:22:38 +09:00

72 lines
1.9 KiB
Python

import os
import typing
import io
import sys
from pyshark.packet import common
DATA_LAYER_NAME = "DATA"
class BaseLayer(common.SlotsPickleable):
"""An object representing a Packet layer."""
__slots__ = ["_layer_name"]
def __init__(self, layer_name):
self._layer_name = layer_name
def get_field(self, name):
raise NotImplementedError()
@property
def field_names(self) -> typing.List[str]:
"""Gets all XML field names of this layer."""
raise NotImplementedError()
def has_field(self, name):
return name in self.field_names
@property
def layer_name(self):
return self._layer_name
def get(self, item, default=None):
"""Gets a field in the layer, or the default if not found.
Works the same way as getattr, but returns the given default if not the field was not found"""
try:
return getattr(self, item)
except AttributeError:
return default
def __dir__(self):
return dir(type(self)) + self.field_names
def __getattr__(self, item):
val = self.get_field(item)
if val is None:
raise AttributeError(f"{item} does not exist in Layer")
return val
def pretty_print(self, writer=None):
if not writer:
writer = sys.stdout
if self.layer_name == DATA_LAYER_NAME:
writer.write('DATA')
return
text = f'Layer {self.layer_name.upper()}{os.linesep}:'
writer.write(common.colored(text, color="yellow", attrs=["bold"]))
self._pretty_print_layer_fields(writer)
def _pretty_print_layer_fields(self, terminal_writer: io.IOBase):
raise NotImplementedError()
def __repr__(self):
return f'<{self.layer_name.upper()} Layer>'
def __str__(self):
writer = io.StringIO()
self.pretty_print(writer=writer)
return writer.getvalue()