pytorch-lightning

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# Copyright The Lightning AI team.
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#
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# Licensed under the Apache License, Version 2.0 (the "License");
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# you may not use this file except in compliance with the License.
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# You may obtain a copy of the License at
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#
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#     http://www.apache.org/licenses/LICENSE-2.0
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#
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# Unless required by applicable law or agreed to in writing, software
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# distributed under the License is distributed on an "AS IS" BASIS,
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# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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# See the License for the specific language governing permissions and
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# limitations under the License.
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import json
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from typing import Any, Dict
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def _duplicate_checker(js):
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    """_duplicate_checker verifies that your JSON object doesn't contain duplicate keys."""
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    result = {}
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    for name, value in js:
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        if name in result:
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            raise ValueError(
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                f"Unable to load JSON. A duplicate key {name} was detected. JSON objects must have unique keys."
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            )
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        result[name] = value
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    return result
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def string2dict(text):
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    """String2dict parses a JSON string into a dictionary, ensuring no keys are duplicated by accident."""
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    if not isinstance(text, str):
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        text = text.decode("utf-8")
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    try:
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        js = json.loads(text, object_pairs_hook=_duplicate_checker)
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        return js
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    except ValueError as ex:
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        raise ValueError(f"Unable to load JSON: {str(ex)}.")
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def is_openapi(obj):
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    """is_openopi checks if an object was generated by OpenAPI."""
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    return hasattr(obj, "swagger_types")
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def create_openapi_object(json_obj: Dict, target: Any):
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    """Create the OpenAPI object from the given JSON dict and based on the target object.
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    Lightning AI uses the target object to make new objects from the given JSON spec so the target must be a valid
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    object.
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    """
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    if not isinstance(json_obj, dict):
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        raise TypeError("json_obj must be a dictionary")
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    if not is_openapi(target):
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        raise TypeError("target must be an openapi object")
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    target_attribs = {}
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    for key, value in json_obj.items():
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        try:
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            # user provided key is not a valid key on openapi object
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            sub_target = getattr(target, key)
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        except AttributeError:
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            raise ValueError(f"Field {key} not found in the target object")
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        if is_openapi(sub_target):  # it's an openapi object
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            target_attribs[key] = create_openapi_object(value, sub_target)
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        else:
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            target_attribs[key] = value
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        # TODO(sherin) - specifically process list and dict and do the validation. Also do the
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        #  verification for enum types
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    return target.__class__(**target_attribs)
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