paimon-python/pypaimon/manifest/__init__.py

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# to you under the Apache License, Version 2.0 (the
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#
#   http://www.apache.org/licenses/LICENSE-2.0
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# Apply fastavro Python 3.6 compatibility patch early, before any other
# manifest modules are imported that might use fastavro
import sys
if sys.version_info[:2] < (3, 8):
    try:
        from pypaimon.manifest import fastavro_py36_compat  # noqa: F401
    except ImportError:
        pass


_SUPPORTED_MANIFEST_COMPRESSIONS = {
    'null', 'deflate', 'snappy', 'zstd', 'bzip2', 'xz',
}


_DEFAULT_MANIFEST_CODEC = 'zstandard'


def avro_codec(compression):
    """Map Paimon manifest.compression config value to fastavro codec name."""
    if not isinstance(compression, str):
        return _DEFAULT_MANIFEST_CODEC
    lower = compression.lower()
    if lower not in _SUPPORTED_MANIFEST_COMPRESSIONS:
        raise ValueError(
            f"Unsupported manifest compression '{compression}'. "
            f"Supported: {sorted(_SUPPORTED_MANIFEST_COMPRESSIONS)}")
    if lower == 'zstd':
        return 'zstandard'
    return lower