fix: fix bugs in "det model describe"

cli/determined_cli/model.py

@@ -112,14 +112,15 @@ def create(args: Namespace) -> None:
 
 def describe(args: Namespace) -> None:
     model = Determined(args.master, None).get_model(args.name)
-    checkpoint = model.get_version()
+    checkpoint = model.get_version(args.version)
 
     if args.json:
         print(json.dumps(model.to_json(), indent=2))
     else:
         render_model(model)
-        print("\n")
-        render_model_version(checkpoint)
+        if checkpoint is not None:
+            print("\n")
+            render_model_version(checkpoint)
 
 
 def register_version(args: Namespace) -> None:

common/determined_common/experimental/model.py

@@ -51,7 +51,7 @@ def __init__(
         self.last_updated_time = last_updated_time
         self.metadata = metadata or {}
 
-    def get_version(self, version: int = 0) -> Checkpoint:
+    def get_version(self, version: int = 0) -> Optional[Checkpoint]:
         """
         Retrieve the checkpoint corresponding to the specified version of the
         model. If no version is specified the latest model version is returned.
@@ -67,6 +67,9 @@ def get_version(self, version: int = 0) -> Checkpoint:
             )
 
             data = resp.json()
+            if data["versions"] == []:
+                return None
+
             latest_version = data["versions"][0]
             return Checkpoint.from_json(
                 {

e2e_tests/tests/test_system.py

@@ -411,7 +411,10 @@ def test_model_registry() -> None:
     checkpoint = d.get_experiment(exp_id).top_checkpoint()
     model_version = mnist.register_version(checkpoint.uuid)
     assert model_version.version == 1
-    assert mnist.get_version().uuid == checkpoint.uuid
+
+    latest_version = mnist.get_version()
+    assert latest_version is not None
+    assert latest_version.uuid == checkpoint.uuid
 
     d.create_model("transformer", "all you need is attention")
     d.create_model("object-detection", "a bounding box model")