feat(python): ConnectionStrategy supports the pickle module (#486)

* feat(python): ConnectionStrategy supports the pickle module

* less constricted quil requirement

* fix missing assert, remove stale code

crates/python/pyproject.toml

@@ -20,7 +20,7 @@ classifiers = [
   "Programming Language :: Python :: 3.11",
   "Operating System :: OS Independent",
 ]
-dependencies = ["quil==0.11.1"]
+dependencies = ["quil>=0.11.2"]
 
 # PEP 621 specifies the [project] table as the source for project metadata. However, Poetry only supports [tool.poetry]
 # We can remove this table once this issue is resolved: https://github.com/python-poetry/poetry/issues/3332

crates/python/src/qpu/api.rs

@@ -8,8 +8,8 @@ use pyo3::{
     pyclass,
     pyclass::CompareOp,
     pyfunction, pymethods,
-    types::{PyComplex, PyDict, PyInt},
-    IntoPy, Py, PyAny, PyObject, PyResult, Python, ToPyObject,
+    types::{PyComplex, PyInt, PyTuple},
+    IntoPy, Py, PyObject, PyResult, Python, ToPyObject,
 };
 use qcs::qpu::api::{
     ApiExecutionOptions, ApiExecutionOptionsBuilder, ConnectionStrategy, ExecutionOptions,
@@ -382,6 +382,7 @@ py_function_sync_async! {
 
 py_wrap_type! {
     #[derive(Debug, Default)]
+    #[pyo3(module = "qcs_sdk.qpu.api")]
     PyExecutionOptions(ExecutionOptions) as "ExecutionOptions"
 }
 impl_repr!(PyExecutionOptions);
@@ -432,21 +433,22 @@ impl PyExecutionOptions {
         }
     }
 
-    fn __getstate__(&self, py: Python<'_>) -> PyResult<Py<PyAny>> {
-        let dict = PyDict::new(py);
-        dict.set_item("connection_strategy", self.connection_strategy())?;
-        dict.set_item("timeout_seconds", self.timeout_seconds())?;
-        dict.set_item("api_options", self.api_options())?;
-        Ok(dict.into())
-    }
-
-    fn __setstate__(&mut self, py: Python<'_>, state: Py<PyAny>) -> PyResult<()> {
-        *self = Self::_from_parts(
-            state.getattr(py, "connection_strategy")?.extract(py)?,
-            state.getattr(py, "timeout_seconds")?.extract(py)?,
-            state.getattr(py, "api_options")?.extract(py)?,
-        )?;
-        Ok(())
+    fn __reduce__<'py>(&mut self, py: Python<'py>) -> PyResult<&'py PyTuple> {
+        let callable = py.get_type::<Self>().getattr("_from_parts")?;
+        Ok(PyTuple::new(
+            py,
+            [
+                callable,
+                PyTuple::new(
+                    py,
+                    &[
+                        self.connection_strategy().into_py(py),
+                        self.timeout_seconds().into_py(py),
+                        self.api_options().into_py(py),
+                    ],
+                ),
+            ],
+        ))
     }
 
     #[staticmethod]
@@ -575,6 +577,7 @@ impl PyApiExecutionOptionsBuilder {
 
 py_wrap_type! {
     #[derive(Default)]
+    #[pyo3(module = "qcs_sdk.qpu.api")]
     PyConnectionStrategy(ConnectionStrategy) as "ConnectionStrategy"
 }
 impl_repr!(PyConnectionStrategy);
@@ -608,4 +611,35 @@ impl PyConnectionStrategy {
             _ => py.NotImplemented(),
         }
     }
+
+    fn __reduce__(&self, py: Python<'_>) -> PyResult<PyObject> {
+        Ok(match self.as_inner() {
+            ConnectionStrategy::Gateway => PyTuple::new(
+                py,
+                &[
+                    py.get_type::<Self>().getattr("gateway")?.to_object(py),
+                    PyTuple::empty(py).to_object(py),
+                ],
+            )
+            .to_object(py),
+            ConnectionStrategy::DirectAccess => PyTuple::new(
+                py,
+                &[
+                    py.get_type::<Self>()
+                        .getattr("direct_access")?
+                        .to_object(py),
+                    PyTuple::empty(py).to_object(py),
+                ],
+            )
+            .to_object(py),
+            ConnectionStrategy::EndpointId(endpoint_id) => PyTuple::new(
+                py,
+                &[
+                    py.get_type::<Self>().getattr("endpoint_id")?.to_object(py),
+                    PyTuple::new(py, [endpoint_id]).to_object(py),
+                ],
+            )
+            .to_object(py),
+        })
+    }
 }

crates/python/tests/qpu/test_api.py

@@ -1,10 +1,13 @@
+import pickle
 import pytest
 
 from qcs_sdk.qpu.translation import (
     translate,
 )
 
 from qcs_sdk.qpu.api import (
+    ConnectionStrategy,
+    ExecutionOptions,
     Register,
     retrieve_results,
     submit,
@@ -44,3 +47,16 @@ def test_submit_retrieve(
 
     job_id = submit(program, memory, quantum_processor_id)
     results = retrieve_results(job_id)
+
+class TestPickle():
+    @pytest.mark.parametrize("strategy", [ConnectionStrategy.gateway(), ConnectionStrategy.direct_access(), ConnectionStrategy.endpoint_id("endpoint_id")])
+    def test_connection_strategy(self, strategy: ConnectionStrategy):
+        pickled = pickle.dumps(strategy)
+        unpickled = pickle.loads(pickled)
+        assert unpickled == strategy
+
+    def test_execution_options(self):
+        options = ExecutionOptions.default()
+        pickled = pickle.dumps(options)
+        unpickled = pickle.loads(pickled)
+        assert unpickled == options