45 lines
1.6 KiB
Python
45 lines
1.6 KiB
Python
import importlib
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import shutil
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def compress(filename: str):
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supp_compr_algo = {"zip": "zipfile", "gzip": "gzip", "bzip2": "bz2", "lzma": "lzma"}
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extensions = {"zip": ".zip", "gzip": ".gz", "bzip2": ".bz2", "lzma": ".xz"}
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assert set(supp_compr_algo.keys()) == set(extensions.keys())
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compression = "bzip2"
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if compression not in supp_compr_algo:
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raise ValueError(
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f"Unknown compression algorithm '{compression}'; must be one of {list(supp_compr_algo.keys())}")
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try_compression(
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file=filename,
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name=compression,
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module_name=supp_compr_algo[compression],
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extension=extensions[compression],
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function=zip_compression if compression == "zip" else compression_open_context_manager
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)
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print(f"Successfully compressed '{filename}' to '{filename + extensions[compression]}' "
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f"using {compression} as compression algorithm")
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def try_compression(file: str, name: str, module_name: str, extension: str, function: callable):
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try:
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compression_module = importlib.import_module(module_name)
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function(file, compression_module, extension)
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except ImportError as ex:
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raise ImportError(f"compression='{name}' failed: required module could not be loaded ({ex})")
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def compression_open_context_manager(file: str, module, extension: str):
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with open(file, "rb") as f_in:
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with module.open(file + extension, "wb") as f_out:
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shutil.copyfileobj(f_in, f_out)
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def zip_compression(file: str, module, extension: str):
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with module.ZipFile(file + extension, "w", compression=module.ZIP_DEFLATED) as z:
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z.write(file)
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