[core worker] Python core worker task execution (#5783)

Executes tasks via the event loop in the C++ core worker. Also properly handles signals (including KeyboardInterrupt), so ctrl-C in a python interactive shell works now (if connecting to an existing cluster).

python/ray/includes/common.pxd

@@ -47,31 +47,34 @@ cdef extern from "ray/common/status.h" namespace "ray" nogil:
         CRayStatus OK()
 
         @staticmethod
-        CRayStatus OutOfMemory()
+        CRayStatus OutOfMemory(const c_string &msg)
 
         @staticmethod
-        CRayStatus KeyError()
+        CRayStatus KeyError(const c_string &msg)
 
         @staticmethod
-        CRayStatus Invalid()
+        CRayStatus Invalid(const c_string &msg)
 
         @staticmethod
-        CRayStatus IOError()
+        CRayStatus IOError(const c_string &msg)
 
         @staticmethod
-        CRayStatus TypeError()
+        CRayStatus TypeError(const c_string &msg)
 
         @staticmethod
-        CRayStatus UnknownError()
+        CRayStatus UnknownError(const c_string &msg)
 
         @staticmethod
-        CRayStatus NotImplemented()
+        CRayStatus NotImplemented(const c_string &msg)
 
         @staticmethod
-        CRayStatus RedisError()
+        CRayStatus ObjectStoreFull(const c_string &msg)
 
         @staticmethod
-        CRayStatus ObjectStoreFull()
+        CRayStatus RedisError(const c_string &msg)
+
+        @staticmethod
+        CRayStatus Interrupted(const c_string &msg)
 
         c_bool ok()
         c_bool IsOutOfMemory()
@@ -81,8 +84,9 @@ cdef extern from "ray/common/status.h" namespace "ray" nogil:
         c_bool IsTypeError()
         c_bool IsUnknownError()
         c_bool IsNotImplemented()
-        c_bool IsRedisError()
         c_bool IsObjectStoreFull()
+        c_bool IsRedisError()
+        c_bool IsInterrupted()
 
         c_string ToString()
         c_string CodeAsString()
@@ -92,6 +96,7 @@ cdef extern from "ray/common/status.h" namespace "ray" nogil:
     # We can later add more of the common status factory methods as needed
     cdef CRayStatus RayStatus_OK "Status::OK"()
     cdef CRayStatus RayStatus_Invalid "Status::Invalid"()
+    cdef CRayStatus RayStatus_NotImplemented "Status::NotImplemented"()
 
 
 cdef extern from "ray/common/status.h" namespace "ray::StatusCode" nogil:
@@ -117,6 +122,8 @@ cdef extern from "ray/protobuf/common.pb.h" nogil:
         pass
     cdef cppclass CWorkerType "ray::WorkerType":
         pass
+    cdef cppclass CTaskType "ray::TaskType":
+        pass
 
 
 # This is a workaround for C++ enum class since Cython has no corresponding
@@ -130,6 +137,11 @@ cdef extern from "ray/protobuf/common.pb.h" nogil:
     cdef CWorkerType WORKER_TYPE_WORKER "ray::WorkerType::WORKER"
     cdef CWorkerType WORKER_TYPE_DRIVER "ray::WorkerType::DRIVER"
 
+cdef extern from "ray/protobuf/common.pb.h" nogil:
+    cdef CTaskType TASK_TYPE_NORMAL_TASK "ray::TaskType::NORMAL_TASK"
+    cdef CTaskType TASK_TYPE_ACTOR_CREATION_TASK "ray::TaskType::ACTOR_CREATION_TASK"  # noqa: E501
+    cdef CTaskType TASK_TYPE_ACTOR_TASK "ray::TaskType::ACTOR_TASK"
+
 
 cdef extern from "ray/common/task/scheduling_resources.h" nogil:
     cdef cppclass ResourceSet "ray::ResourceSet":