Source code for edxia.io.loader.stack_loader

# Copyright (c) 2019 Fabien Georget <fabien.georget@epfl.ch>, EPFL
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from copy import copy

from .base_loader import AbstractLoader

class StackLoader(AbstractLoader):
    """
    Loader using a set of maps already read (and optionally filtered) using a different loader.

    """
    def __init__(self, stack):
        """
        Create a loader object from a stack of maps.

        :param stack: an instance of a :class:`edxia.core.map.MapsStack`.
        """
        self._stack = copy(stack)
        super().__init__(stack.parent)

    def load_stack(self, components=None, factors=None):
        """ Copy and return the stack of maps of the loader."""
        if components is None and factors is None:
            return copy(self._stack)
        else:
            return super().load_stack(components=components, factors=factors)

    def load_edsmap_single(self, component):
        eds_map = self._stack.map(component)
        return eds_map