Add a helpful exception when forgetting to await an async class (#396)

kr8s/_objects.py

@@ -77,14 +77,14 @@ def __init__(self, resource: dict, namespace: str = None, api: Api = None) -> No
             )
         if namespace is not None:
             self._raw["metadata"]["namespace"] = namespace
-        self.api = api
-        if self.api is None and not self._asyncio:
-            self.api = kr8s.api()
+        self._api = api
+        if self._api is None and not self._asyncio:
+            self._api = kr8s.api()
 
     def __await__(self):
         async def f():
-            if self.api is None:
-                self.api = await kr8s.asyncio.api()
+            if self._api is None:
+                self._api = await kr8s.asyncio.api()
             return self
 
         return f().__await__()
@@ -108,6 +108,19 @@ def __eq__(self, other):
             return False
         return True
 
+    @property
+    def api(self):
+        if self._api is None and self._asyncio:
+            raise RuntimeError(
+                f"{self.__repr__()} has not been initialized with an API object. "
+                "Did you forget to await it?"
+            )
+        return self._api
+
+    @api.setter
+    def api(self, value):
+        self._api = value
+
     @property
     def raw(self) -> str:
         """Raw object returned from the Kubernetes API."""

kr8s/tests/test_objects.py

@@ -151,6 +151,13 @@ async def test_pod_wait_ready(example_pod_spec):
     await pod.wait("delete")
 
 
+async def test_pod_missing_await_error(example_pod_spec):
+    pod = Pod(example_pod_spec)  # We intentionally forget to await here
+    assert pod._api is None
+    with pytest.raises(RuntimeError, match="forget to await it"):
+        await pod.create()
+
+
 async def test_pod_wait_multiple_conditions(example_pod_spec):
     pod = await Pod(example_pod_spec)
     await pod.create()