First draft "namespace path" named tuple; probably will discard

tractor/_portal.py

@@ -14,11 +14,13 @@
 # You should have received a copy of the GNU Affero General Public License
 # along with this program.  If not, see <https://www.gnu.org/licenses/>.
 
-"""
+'''
 Memory boundary "Portals": an API for structured
 concurrency linked tasks running in disparate memory domains.
 
-"""
+'''
+from __future__ import annotations
+from typing import NamedTuple
 import importlib
 import inspect
 from typing import (
@@ -66,11 +68,38 @@ async def maybe_open_nursery(
             yield nursery
 
 
-def func_deats(func: Callable) -> tuple[str, str]:
-    return (
-        func.__module__,
-        func.__name__,
-    )
+class NamespacePath(NamedTuple):
+    '''
+    A serializeable description of a (function) object location
+    described by the target's module path and its namespace key.
+
+    '''
+    mod: str
+    key: str
+
+    def load(self) -> Callable:
+        return getattr(
+            importlib.import_module(self.mod),
+            self.key
+        )
+
+    @classmethod
+    def from_ref(
+        cls,
+        obj,
+
+    ) -> NamespacePath:
+        return cls(
+            obj.__module__,
+            obj.__name__,
+        )
+
+
+# def func_deats(func: Callable) -> NamespacePath[str, str]:
+#     return NamespacePath(
+#         func.__module__,
+#         func.__name__,
+#     )
 
 
 def _unwrap_msg(
@@ -86,6 +115,7 @@ def _unwrap_msg(
         assert msg.get('cid'), "Received internal error at portal?"
         raise unpack_error(msg, channel)
 
+
 class MessagingError(Exception):
     'Some kind of unexpected SC messaging dialog issue'
 
@@ -316,7 +346,8 @@ class Portal:
                 raise TypeError(
                     f'{func} must be a non-streaming async function!')
 
-            fn_mod_path, fn_name = func_deats(func)
+            # fn_mod_path, fn_name = func_deats(func)
+            fn_mod_path, fn_name = NamespacePath.from_ref(func)
 
         ctx = await self.actor.start_remote_task(
             self.channel,
@@ -346,7 +377,8 @@ class Portal:
                 raise TypeError(
                     f'{async_gen_func} must be an async generator function!')
 
-        fn_mod_path, fn_name = func_deats(async_gen_func)
+        # fn_mod_path, fn_name = func_deats(async_gen_func)
+        fn_mod_path, fn_name = NamespacePath.from_ref(async_gen_func)
         ctx = await self.actor.start_remote_task(
             self.channel,
             fn_mod_path,
@@ -412,7 +444,8 @@ class Portal:
             raise TypeError(
                 f'{func} must be an async generator function!')
 
-        fn_mod_path, fn_name = func_deats(func)
+        # fn_mod_path, fn_name = func_deats(func)
+        fn_mod_path, fn_name = NamespacePath.from_ref(func)
 
         ctx = await self.actor.start_remote_task(
             self.channel,
@@ -430,7 +463,7 @@ class Portal:
             first = msg['started']
             ctx._started_called = True
 
-        except KeyError as kerr:
+        except KeyError:
             assert msg.get('cid'), ("Received internal error at context?")
 
             if msg.get('error'):