57 lines
1.6 KiB
Python
57 lines
1.6 KiB
Python
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import json
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from typing import Dict, Any, Tuple
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class PackingError(Exception):
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pass
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class GXPacker:
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MAGIC = b'XIC'
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VERSION = 1
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@staticmethod
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def pack(manifest: Dict[str, Any], compressed_payload: bytes) -> bytes:
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try:
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header = GXPacker.MAGIC
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header += bytes([GXPacker.VERSION])
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manifest_json = json.dumps(manifest, separators=(',', ':')).encode('utf-8')
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manifest_len = len(manifest_json)
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header += manifest_len.to_bytes(4, 'big')
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result = header + manifest_json + compressed_payload
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return result
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except Exception as e:
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raise PackingError(f"Packing failed: {e}")
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@staticmethod
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def unpack(data: bytes) -> Tuple[Dict[str, Any], bytes]:
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try:
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if len(data) < 8:
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raise PackingError("Data too short for GX header")
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if data[:3] != GXPacker.MAGIC:
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raise PackingError("Invalid magic number")
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version = data[3]
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if version != GXPacker.VERSION:
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raise PackingError(f"Unsupported version: {version}")
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manifest_len = int.from_bytes(data[4:8], 'big')
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if len(data) < 8 + manifest_len:
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raise PackingError("Incomplete manifest")
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manifest_json = data[8:8 + manifest_len]
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compressed_payload = data[8 + manifest_len:]
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manifest = json.loads(manifest_json.decode('utf-8'))
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return manifest, compressed_payload
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except PackingError:
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raise
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except Exception as e:
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raise PackingError(f"Unpacking failed: {e}")
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