Source code for volatility3.framework.automagic.construct_layers

# This file is Copyright 2019 Volatility Foundation and licensed under the Volatility Software License 1.0
# which is available at
"""An automagic module to use configuration data to configure and then
construct classes that fulfill the descendants of a :class:`~volatility3.framewo

import logging
import sys
from typing import List

from volatility3 import framework
from volatility3.framework import constants
from volatility3.framework import interfaces

vollog = logging.getLogger(__name__)

[docs]class ConstructionMagic(interfaces.automagic.AutomagicInterface): """Constructs underlying layers. Class to run through the requirement tree of the :class:`~volatility3.framework.interfaces.configuration.ConfigurableInterface` and from the bottom of the tree upwards, attempt to construct all :class:`~volatility3.framework.interfaces.configuration.ConstructableRequirementInterface` based classes. :warning: This `automagic` should run first to allow existing configurations to have been constructed for use by later automagic """ priority = 0 def __call__( self, context: interfaces.context.ContextInterface, config_path: str, requirement: interfaces.configuration.RequirementInterface, progress_callback=None, optional=False, ) -> List[str]: # Make sure we import the layers, so they can reconstructed framework.import_files(sys.modules["volatility3.framework.layers"]) result: List[str] = [] if requirement.unsatisfied(context, config_path): # Having called validate at the top level tells us both that we need to dig deeper # but also ensures that TranslationLayerRequirements have got the correct subrequirements if their class is populated subreq_config_path = interfaces.configuration.path_join( config_path, ) for subreq in requirement.requirements.values(): try: self( context, subreq_config_path, subreq, optional=optional or subreq.optional, ) except Exception as e: # We don't really care if this fails, it tends to mean the configuration isn't complete for that item vollog.log( constants.LOGLEVEL_VVVV, f"Construction Exception occurred: {e}" ) invalid = subreq.unsatisfied(context, subreq_config_path) # We want to traverse optional paths, so don't check until we've tried to validate # We also don't want to emit a debug message when a parent is optional, hence the optional parameter if invalid and not (optional or subreq.optional): vollog.log( constants.LOGLEVEL_V, f"Failed on requirement: {subreq_config_path}", ) result.append( interfaces.configuration.path_join( subreq_config_path, ) ) if result: return result elif isinstance( requirement, interfaces.configuration.ConstructableRequirementInterface ): # We know all the subrequirements are filled, so let's populate requirement.construct(context, config_path) if progress_callback is not None: progress_callback(100, "Reconstruction finished") return []