kd.types.StreamReader API

Stream reader.

Note: This class supports parametrization like StreamReader[T].

StreamReader.read_available(limit=None)

Returns the available items from the stream.

Returns an empty list if no more data is currently available and
the stream is still open.

Returns `None` if the stream has been exhausted and closed without
an error; otherwise, raises the error passed during closing.

Args:
  limit: The maximum number of items to return.

StreamReader.subscribe_once(callback, /)

Registers a one-time callback for when items arrive or the stream closes.

The `callback` is executed without arguments. It may run synchronously
on the current thread if the stream is already ready, or asynchronously
on the C++ to Python bridge thread. To avoid blocking other notifications
on the bridge thread, the callback must execute quickly; any non-trivial
processing should be offloaded to a separate thread pool.

When the `callback` is invoked, the subsequent `read_available()`
call is guaranteed to return a non-trivial result:
 * a non-empty list if there are more items available,
 * `None` if the stream was closed without an error, or
 * raise an error if the stream was closed with an error.