Async socket reader with pushback buffer support. This class wraps an asyncio StreamReader and provides the ability to "unread" data back into a buffer for re-parsing. Performance optimization: Reuses BytesIO buffer with truncate/seek instead of creating new objects to reduce GC pr
| 12 | |
| 13 | |
| 14 | class AsyncUnreader: |
| 15 | """Async socket reader with pushback buffer support. |
| 16 | |
| 17 | This class wraps an asyncio StreamReader and provides the ability |
| 18 | to "unread" data back into a buffer for re-parsing. |
| 19 | |
| 20 | Performance optimization: Reuses BytesIO buffer with truncate/seek |
| 21 | instead of creating new objects to reduce GC pressure. |
| 22 | """ |
| 23 | |
| 24 | def __init__(self, reader, max_chunk=8192): |
| 25 | """Initialize the async unreader. |
| 26 | |
| 27 | Args: |
| 28 | reader: asyncio.StreamReader instance |
| 29 | max_chunk: Maximum bytes to read at once |
| 30 | """ |
| 31 | self.reader = reader |
| 32 | self.buf = io.BytesIO() |
| 33 | self.max_chunk = max_chunk |
| 34 | self._buf_start = 0 # Start position of valid data in buffer |
| 35 | |
| 36 | def _reset_buffer(self): |
| 37 | """Reset buffer for reuse instead of creating new BytesIO.""" |
| 38 | self.buf.seek(0) |
| 39 | self.buf.truncate(0) |
| 40 | self._buf_start = 0 |
| 41 | |
| 42 | def _get_buffered_data(self): |
| 43 | """Get all buffered data and reset buffer.""" |
| 44 | self.buf.seek(self._buf_start) |
| 45 | data = self.buf.read() |
| 46 | self._reset_buffer() |
| 47 | return data |
| 48 | |
| 49 | def _buffer_size(self): |
| 50 | """Get size of buffered data.""" |
| 51 | end = self.buf.seek(0, io.SEEK_END) |
| 52 | return end - self._buf_start |
| 53 | |
| 54 | async def read(self, size=None): |
| 55 | """Read data from the stream, using buffered data first. |
| 56 | |
| 57 | Args: |
| 58 | size: Number of bytes to read. If None, returns all buffered |
| 59 | data or reads a single chunk. |
| 60 | |
| 61 | Returns: |
| 62 | bytes: Data read from buffer or stream |
| 63 | """ |
| 64 | if size is not None and not isinstance(size, int): |
| 65 | raise TypeError("size parameter must be an int or long.") |
| 66 | |
| 67 | if size is not None: |
| 68 | if size == 0: |
| 69 | return b"" |
| 70 | if size < 0: |
| 71 | size = None |
no outgoing calls