aria/parser/loading/source.py

# Licensed to the Apache Software Foundation (ASF) under one or more
# contributor license agreements.  See the NOTICE file distributed with
# this work for additional information regarding copyright ownership.
# The ASF licenses this file to You under the Apache License, Version 2.0
# (the "License"); you may not use this file except in compliance with
# the License.  You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
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from .location import LiteralLocation, UriLocation
from .literal import LiteralLoader
from .uri import UriTextLoader


class LoaderSource(object):
    """
    Base class for ARIA loader sources.

    Loader sources provide appropriate :class:`Loader` instances for locations.
    """

    def get_loader(self, context, location, origin_location):
        raise NotImplementedError


class DefaultLoaderSource(LoaderSource):
    """
    The default ARIA loader source will generate a :class:`UriTextLoader` for
    :class:`UriLocation` and a :class:`LiteralLoader` for a :class:`LiteralLocation`.
    """

    def get_loader(self, context, location, origin_location):
        if isinstance(location, UriLocation):
            return UriTextLoader(context, location, origin_location)
        elif isinstance(location, LiteralLocation):
            return LiteralLoader(location)

        return super(DefaultLoaderSource, self).get_loader(context, location, origin_location)