paimon-python/pypaimon/read/reader/iface/record_reader.py

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from abc import ABC, abstractmethod
from typing import Generic, Optional, TypeVar

from pypaimon.read.reader.iface.record_iterator import RecordIterator

T = TypeVar('T')


class RecordReader(Generic[T], ABC):
    """
    The reader that reads the batches of records.
    """

    @abstractmethod
    def read_batch(self) -> Optional[RecordIterator[T]]:
        """
        Reads one batch as a RecordIterator. The method should return null when reaching the end of the input.
        """

    @abstractmethod
    def close(self):
        """
        Closes the reader and should release all resources.
        """