cosmos_predict1/utils/easy_io/handlers/json_handler.py

# SPDX-FileCopyrightText: Copyright (c) 2025 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
# SPDX-License-Identifier: Apache-2.0
#
# 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.

import json

import numpy as np

from cosmos_predict1.utils.easy_io.handlers.base import BaseFileHandler


def set_default(obj):
    """Set default json values for non-serializable values.

    It helps convert ``set``, ``range`` and ``np.ndarray`` data types to list.
    It also converts ``np.generic`` (including ``np.int32``, ``np.float32``,
    etc.) into plain numbers of plain python built-in types.
    """
    if isinstance(obj, (set, range)):
        return list(obj)
    elif isinstance(obj, np.ndarray):
        return obj.tolist()
    elif isinstance(obj, np.generic):
        return obj.item()
    raise TypeError(f"{type(obj)} is unsupported for json dump")


class JsonHandler(BaseFileHandler):
    def load_from_fileobj(self, file):
        return json.load(file)

    def dump_to_fileobj(self, obj, file, **kwargs):
        kwargs.setdefault("default", set_default)
        json.dump(obj, file, **kwargs)

    def dump_to_str(self, obj, **kwargs):
        kwargs.setdefault("default", set_default)
        return json.dumps(obj, **kwargs)