# Copyright 2020 Huawei Technologies Co., Ltd
#
# Licensed 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
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
# ============================================================================
"""File operation module."""
import os


def _is_obs(url):
    return url.startswith("obs://") or url.startswith("s3://")


def read(url, binary=False):
    if _is_obs(url):
        # TODO read cloud file.
        return None

    with open(url, "rb" if binary else "r") as f:
        return f.read()


def walk(url):
    if _is_obs(url):
        # TODO read cloud file.
        return None
    return os.walk(url)
