Implement select to enable waiting for a specific number of remote objects to be ready. (#369)

src/raylib.cc

@@ -897,6 +897,26 @@ static PyObject* request_object(PyObject* self, PyObject* args) {
   Py_RETURN_NONE;
 }
 
+static PyObject* ray_select(PyObject* self, PyObject* args) {
+  Worker* worker;
+  PyObject* objectids;
+  if (!PyArg_ParseTuple(args, "O&O", &PyObjectToWorker, &worker, &objectids)) {
+    return NULL;
+  }
+  std::vector<ObjectID> objectids_vec;
+  for (size_t i = 0; i < PyList_Size(objectids); ++i) {
+    ObjectID objectid;
+    PyObjectToObjectID(PyList_GetItem(objectids, i), &objectid);
+    objectids_vec.push_back(objectid);
+  }
+  std::vector<int> indices = worker->select(objectids_vec);
+  PyObject* result = PyList_New(indices.size());
+  for (size_t i = 0; i < indices.size(); ++i) {
+    PyList_SetItem(result, i, PyInt_FromLong(indices[i]));
+  }
+  return result;
+}
+
 static PyObject* alias_objectids(PyObject* self, PyObject* args) {
   Worker* worker;
   ObjectID alias_objectid;
@@ -1061,6 +1081,7 @@ static PyMethodDef RayLibMethods[] = {
  { "get_object", get_object, METH_VARARGS, "get protocol buffer object from the local object store" },
  { "get_objectid", get_objectid, METH_VARARGS, "register a new object reference with the scheduler" },
  { "request_object" , request_object, METH_VARARGS, "request an object to be delivered to the local object store" },
+ { "ray_select" , ray_select, METH_VARARGS, "checks the scheduler to see if a object can be gotten" },
  { "alias_objectids", alias_objectids, METH_VARARGS, "make two objectids refer to the same object" },
  { "wait_for_next_message", wait_for_next_message, METH_VARARGS, "get next message from scheduler (blocking)" },
  { "submit_task", submit_task, METH_VARARGS, "call a remote function" },