0.6.5: require python-introspect 0.3

CHANGELOG.md

@@ -0,0 +1,27 @@
+# Changelog
+
+## 0.6.5
+
+Requires `python-introspect>=0.3.0,<0.4` (was `<0.3`).
+
+Wire form:
+- No message declared by zmqruntime changes on the wire: none of them has a field
+  whose declared type admits several classes, so a 0.6.4 peer and a 0.6.5 peer
+  exchange the same bytes for zmqruntime's own messages.
+- An application message does change if it declares such a field (a union of two
+  or more dataclasses, an abstract dataclass, or an `AutoRegisterMeta` class): the
+  value is sent as `{tag: fields}` and read by its tag. There is no reader for the
+  untagged form. zmqruntime has no protocol version of its own; a client refuses
+  a server of another application version only when the application declares an
+  `EndpointApplication(identifier, version)` and requires it, so applications
+  whose messages changed form must raise that version.
+- A field declared as one concrete dataclass carries that class only. A subclass
+  instance with more fields is refused when decoded.
+
+Fixed:
+- A control request encodes its body by the declared field types, the same way it
+  is decoded. Before, each body value was encoded on its own, so under
+  python-introspect 0.3 a request field admitting several classes would have
+  been sent untagged and then refused by the receiver.
+- `ViewerInstance.visualizer` resolves at run time (`VisualizerProcessManager`
+  was imported only for type checkers).

pyproject.toml

@@ -4,7 +4,7 @@ build-backend = "hatchling.build"
 
 [project]
 name = "zmqruntime"
-version = "0.6.4"
+version = "0.6.5"
 description = "Generic ZMQ-based distributed execution framework"
 authors = [{name = "Tristan Simas", email = "tristan.simas@mail.mcgill.ca"}]
 license = {text = "MIT"}
@@ -31,7 +31,7 @@ dependencies = [
     "portalocker>=2.8.2",
     "pyzmq>=22.0",
     "psutil>=5.9",
-    "python-introspect>=0.2.5,<0.3",
+    "python-introspect>=0.3.0,<0.4",
     "typing-extensions>=4.0.0",
 ]
 

src/zmqruntime/messages.py

@@ -469,9 +469,10 @@ def from_wire_payload(cls, wire_payload: bytes) -> Self:
         return cls.from_dict(payload)
 
     def to_dict(self) -> dict[str, object]:
+        declared = to_jsonable(replace(self, operation_deadline=None))
         payload = {
-            MessageFields.TYPE: self.message_type.value,
-            **{name: to_jsonable(getattr(self, name)) for name in self.body_fields()},
+            MessageFields.TYPE: declared["message_type"],
+            **{name: declared[name] for name in self.body_fields()},
         }
         return (payload if self.operation_deadline is None else
                 self.with_observation_budget(payload, self.operation_deadline))

src/zmqruntime/viewer_state.py

@@ -16,13 +16,11 @@
 from abc import ABC, abstractmethod
 from dataclasses import dataclass, field
 from enum import Enum, auto
-from typing import TYPE_CHECKING, Any, Callable, Dict, List, Optional, Tuple
+from typing import Any, Callable, Dict, List, Optional, Tuple
 
+from zmqruntime.streaming.process_manager import VisualizerProcessManager
 from zmqruntime.subscription import CallbackSubscription, SubscriptionABC
 
-if TYPE_CHECKING:
-    from zmqruntime.streaming.process_manager import VisualizerProcessManager
-
 logger = logging.getLogger(__name__)
 
 
@@ -42,7 +40,7 @@ class ViewerInstance:
 
     viewer_type: str
     port: int
-    visualizer: "VisualizerProcessManager"
+    visualizer: VisualizerProcessManager
     state: ViewerState = ViewerState.LAUNCHING
     created_at: float = field(default_factory=time.time)
     last_used: float = field(default_factory=time.time)
@@ -59,21 +57,21 @@ def is_healthy(self) -> bool:
         return self.visualizer.is_running
 
 
-VisualizerFactory = Callable[[], "VisualizerProcessManager"]
+VisualizerFactory = Callable[[], VisualizerProcessManager]
 
 
 class ViewerReuseAdmissionABC(ABC):
     """Caller-owned constraints admitted inside atomic viewer acquisition."""
 
     @abstractmethod
-    def require_reusable(self, visualizer: "VisualizerProcessManager") -> None:
+    def require_reusable(self, visualizer: VisualizerProcessManager) -> None:
         """Raise without changing the existing instance when reuse is forbidden."""
 
 
 class HealthyViewerReuseAdmission(ViewerReuseAdmissionABC):
     """Generic callers require health but declare no application launch settings."""
 
-    def require_reusable(self, visualizer: "VisualizerProcessManager") -> None:
+    def require_reusable(self, visualizer: VisualizerProcessManager) -> None:
         pass
 
 
@@ -141,7 +139,7 @@ def get_or_create_viewer(
         ready_timeout: float = 30.0,
         *,
         reuse_admission: ViewerReuseAdmissionABC = HealthyViewerReuseAdmission(),
-    ) -> Tuple["VisualizerProcessManager", bool]:
+    ) -> Tuple[VisualizerProcessManager, bool]:
         """
         Atomically get existing viewer or create a new one.
 
@@ -294,7 +292,7 @@ def _remove_viewer_locked(self, key: Tuple[str, int]) -> None:
             except Exception as e:
                 logger.warning("Error stopping viewer during removal: %s", e)
 
-    def get_viewer(self, viewer_type: str, port: int) -> Optional["VisualizerProcessManager"]:
+    def get_viewer(self, viewer_type: str, port: int) -> Optional[VisualizerProcessManager]:
         """Get existing viewer if healthy."""
         key = (viewer_type, port)
         with self._lock:
@@ -509,7 +507,7 @@ def get_or_create_viewer(
     ready_timeout: float = 30.0,
     *,
     reuse_admission: ViewerReuseAdmissionABC = HealthyViewerReuseAdmission(),
-) -> Tuple["VisualizerProcessManager", bool]:
+) -> Tuple[VisualizerProcessManager, bool]:
     """
     Convenience function for atomic viewer get-or-create.
 

tests/test_messages.py

@@ -313,3 +313,44 @@ def test_task_progress_carries_the_application_phase_vocabulary() -> None:
 
     assert wire["phase"] == wire["status"] == "compiling"
     assert TaskProgress.from_dict(wire).phase == "compiling"
+
+
+@dataclass(frozen=True)
+class _ByName:
+    name: str
+
+
+@dataclass(frozen=True)
+class _ByAlias:
+    name: str
+
+
+@dataclass(frozen=True, slots=True)
+class _SelectRequest(ControlRequestHeader):
+    selector: _ByName | _ByAlias
+
+
+def test_request_body_field_admitting_several_classes_is_tagged_on_the_wire() -> None:
+    request = _SelectRequest(ControlMessageType.STATUS, _ByAlias("a"))
+
+    payload = request.to_dict()
+
+    assert payload == {"type": "status", "selector": {"_ByAlias": {"name": "a"}}}
+    assert _SelectRequest.from_dict(payload) == request
+    assert _SelectRequest.from_wire_payload(request.to_wire_payload()) == request
+    with pytest.raises(ValueError, match="_ByName"):
+        _SelectRequest.from_dict({"type": "status", "selector": {"Unknown": {"name": "a"}}})
+
+
+@dataclass(frozen=True)
+class _NamedProcessIdentity(ProcessIdentity):
+    name: str = ""
+
+
+def test_field_declared_as_one_class_refuses_a_subclass_with_more_fields() -> None:
+    from zmqruntime import messages
+
+    launch = messages.EndpointLaunch("/code", _NamedProcessIdentity(1, 2.0, "n"), "any_session")
+
+    with pytest.raises(ValueError, match="name"):
+        messages.EndpointLaunch.from_dict(launch.to_dict())