Function ExposeOperator

dali/python/backend_impl.cc:3031–3069

}

void ExposeOperator(py::module &m) {
  py::class_<OperatorBase, py::smart_holder>(m, "_Operator")
    .def(py::init([](const OpSpec &spec) {
      DomainTimeRange tr("Instantiate " + GetOpDisplayName(spec, true), kDynamicDefaultColor);
      return dali::InstantiateOperator(spec);
    }))
    .def("Setup", [](OperatorBase &self, std::vector<dali::OutputDesc> &out_descs, Workspace &ws) {
      py::gil_scoped_release interpreter_unlock{};
      DomainTimeRange tr("Setup " + GetOpDisplayName(self.GetSpec(), true), kDynamicDefaultColor);
      return self.Setup(out_descs, ws);
    })
    .def("Run", [](OperatorBase &self, Workspace &ws) {
      py::gil_scoped_release interpreter_unlock{};
      DomainTimeRange tr("Run " + GetOpDisplayName(self.GetSpec(), true), kDynamicDefaultColor);
      self.Run(ws);
    } )
    .def("SetupAndRun", [](OperatorBase &self, PyWorkspace &ws, std::optional<int> batch_size) {
      py::gil_scoped_release interpreter_unlock{};
      SetupAndRun(self, ws, batch_size);
    }, "ws"_a, "batch_size"_a = py::none())
    .def("GetReaderMeta", [](OperatorBase &self) {
      return ReaderMetaToDict(self.GetReaderMeta());
    })
    .def("SaveCheckpoint", [](OperatorBase &self, py::object stream) -> py::bytes {
      // Saves the operator state, serializes it and returns the serialized representation.
      // Used by the dynamic API to expose stateful operator checkpointing to Python.
      // The returned blob may contain arbitrary bytes (e.g. protobuf-serialized loader
      // state), so it is returned as `py::bytes` to avoid UTF-8 conversion.
      OpCheckpoint cpt(self.GetSpec().SchemaName());
      self.SaveState(cpt, AccessOrderFromPythonStreamObj(stream));
      return py::bytes(self.SerializeCheckpoint(cpt));
    }, "stream"_a = py::none())
    .def("RestoreCheckpoint", [](OperatorBase &self, const std::string &data) {
      // Deserializes the operator state from a string/bytes blob and restores it.
      OpCheckpoint cpt(self.GetSpec().SchemaName());
      self.DeserializeCheckpoint(cpt, data);
      self.RestoreState(cpt);
    }, "data"_a);
}

auto GetSupportedBackends(OpSchema &schema) {
  std::vector<std::string_view> ret;