Stanislav Hejny
48 lines
1.7 KiB
Python
48 lines
1.7 KiB
Python
import json
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import struct
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import io
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import pika
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class StreamParser:
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def __init__(self):
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self.buffer = io.BytesIO() # Buffer to accumulate chunks
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self.metadata_length = None # Length of the metadata
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self.metadata = None # Parsed JSON metadata
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self.file_writer = None # File writer for the remaining data
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def process_chunk(self, chunk):
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"""
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Process a chunk of data and handle it according to the rules.
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"""
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self.buffer.write(chunk)
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# If metadata length is not yet known, try to read it
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if self.metadata_length is None and self.buffer.tell() >= 4:
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self.buffer.seek(0)
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self.metadata_length = struct.unpack('>I', self.buffer.read(4))[0]
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# If metadata length is known but metadata is not yet parsed, try to parse it
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if self.metadata_length is not None and self.metadata is None:
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if self.buffer.tell() >= 4 + self.metadata_length:
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self.buffer.seek(4)
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metadata_bytes = self.buffer.read(self.metadata_length)
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self.metadata = json.loads(metadata_bytes.decode('utf-8'))
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print("Metadata:", self.metadata)
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# Prepare to write the remaining data to a file
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self.file_writer = open(self.metadata.get("filename", "output_file"), "wb")
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# If metadata is parsed, write the remaining data to the file
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if self.metadata is not None:
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remaining_data = self.buffer.read()
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if remaining_data:
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self.file_writer.write(remaining_data)
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def close(self):
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"""
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Close the file writer and clean up.
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"""
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if self.file_writer:
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self.file_writer.close()
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self.buffer.close()
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