state.py

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# 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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# 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.

from dataclasses import dataclass
from pandas import DataFrame
from pyarrow import Table
from typing import Optional

from .schema import Schema, AttributeType
from .schema.attribute_type import FROM_PYOBJECT_MAPPING


@dataclass
class State:
    def __init__(
        self, table: Optional[Table] = None, pass_to_all_downstream: bool = True
    ):
        self.schema = Schema()
        self.passToAllDownstream = pass_to_all_downstream
        if table is not None:
            self.__dict__.update(table.to_pandas().iloc[0].to_dict())
            self.schema = Schema(table.schema)

    @classmethod
    def from_tuple(cls, tuple, schema):
        obj = cls()
        obj.__dict__.update(tuple.as_dict())
        obj.schema = schema
        return obj

    @classmethod
    def from_dict(cls, dictionary):
        obj = cls()
        for item in dictionary:
            obj.add(item, dictionary[item])
        return obj

    def add(
        self, key: str, value: any, value_type: Optional[AttributeType] = None
    ) -> None:
        if key not in self.__dict__:
            if value_type is not None:
                self.schema.add(key, value_type)
            elif key != "schema":
                self.schema.add(key, FROM_PYOBJECT_MAPPING[type(value)])
        self.__dict__[key] = value

    def get(self, key: str) -> any:
        return self.__dict__[key]

    def to_table(self) -> Table:
        return Table.from_pandas(
            df=DataFrame([self.__dict__]),
            schema=self.schema.as_arrow_schema(),
        )

    def to_dict(self) -> dict:
        dictionary = self.__dict__.copy()
        del dictionary["passToAllDownstream"]
        del dictionary["schema"]
        return dictionary

    def __setattr__(self, key: str, value: any) -> None:
        self.add(key, value)

    def __setitem__(self, key: str, value: any) -> None:
        self.add(key, value)

    def __getitem__(self, key: str) -> any:
        return self.get(key)

    def __str__(self) -> str:
        content = ", ".join(
            [
                repr(key) + ": " + repr(value)
                for key, value in self.__dict__.items()
                if key != "schema"
            ]
        )
        return f"State[{content}]"

    __repr__ = __str__