Class StreamReader

Lib/asyncio/streams.py:410–773

                warnings.warn(f"unclosed {self!r}", ResourceWarning)

class StreamReader:

    _source_traceback = None

    def __init__(self, limit=_DEFAULT_LIMIT, loop=None):
        # The line length limit is  a security feature;
        # it also doubles as half the buffer limit.

        if limit <= 0:
            raise ValueError('Limit cannot be <= 0')

        self._limit = limit
        if loop is None:
            self._loop = events.get_event_loop()
        else:
            self._loop = loop
        self._buffer = bytearray()
        self._eof = False    # Whether we're done.
        self._waiter = None  # A future used by _wait_for_data()
        self._exception = None
        self._transport = None
        self._paused = False
        if self._loop.get_debug():
            self._source_traceback = format_helpers.extract_stack(
                sys._getframe(1))

    def __repr__(self):
        info = ['StreamReader']
        if self._buffer:
            info.append(f'{len(self._buffer)} bytes')
        if self._eof:
            info.append('eof')
        if self._limit != _DEFAULT_LIMIT:
            info.append(f'limit={self._limit}')
        if self._waiter:
            info.append(f'waiter={self._waiter!r}')
        if self._exception:
            info.append(f'exception={self._exception!r}')
        if self._transport:
            info.append(f'transport={self._transport!r}')
        if self._paused:
            info.append('paused')
        return '<{}>'.format(' '.join(info))

    def exception(self):
        return self._exception

    def set_exception(self, exc):
        self._exception = exc

        waiter = self._waiter
        if waiter is not None:
            self._waiter = None
            if not waiter.cancelled():
                waiter.set_exception(exc)

    def _wakeup_waiter(self):
        """Wakeup read*() functions waiting for data or EOF."""