Apply type casting & remove empty kwarg for Command (#108)

Currently, all kwargs are passed into `App.command` as `str`. Empty
kwarg is passed as empty string.

In this PR, we remove any empty kwarg, and apply casting based on the
kwarg annotation for primitive types

src/databricks/labs/blueprint/cli.py

@@ -36,6 +36,12 @@ def prompts_argument_name(self) -> str | None:
                 return param.name
         return None
 
+    def get_argument_type(self, argument_name: str) -> str | None:
+        sig = inspect.signature(self.fn)
+        if argument_name not in sig.parameters:
+            return None
+        return sig.parameters[argument_name].annotation.__name__
+
 
 class App:
     def __init__(self, __file: str):
@@ -77,9 +83,18 @@ def _route(self, raw):
             log_level = "info"
         databricks_logger = logging.getLogger("databricks")
         databricks_logger.setLevel(log_level.upper())
-        kwargs = {k.replace("-", "_"): v for k, v in flags.items()}
+        kwargs = {k.replace("-", "_"): v for k, v in flags.items() if v != ""}
+        cmd = self._mapping[command]
+        # modify kwargs to match the type of the argument
+        for kwarg in list(kwargs.keys()):
+            match cmd.get_argument_type(kwarg):
+                case "int":
+                    kwargs[kwarg] = int(kwargs[kwarg])
+                case "bool":
+                    kwargs[kwarg] = kwargs[kwarg].lower() == "true"
+                case "float":
+                    kwargs[kwarg] = float(kwargs[kwarg])
         try:
-            cmd = self._mapping[command]
             if cmd.needs_workspace_client():
                 kwargs["w"] = self._workspace_client()
             elif cmd.is_account:

tests/unit/test_cli.py

@@ -11,6 +11,10 @@
         "command": "foo",
         "flags": {
             "name": "y",
+            "age": "100",
+            "salary": "100.5",
+            "address": "",
+            "is_customer": "true",
             "log_level": "disabled",
         },
     }
@@ -22,27 +26,27 @@ def test_commands():
     app = App(inspect.getfile(App))
 
     @app.command(is_unauthenticated=True)
-    def foo(name: str):
+    def foo(name: str, age: int, salary: float, is_customer: bool, address: str = "default"):
         """Some comment"""
-        some(name)
+        some(name, age, salary, is_customer, address)
 
     with mock.patch.object(sys, "argv", [..., FOO_COMMAND]):
         app()
 
-    some.assert_called_with("y")
+    some.assert_called_with("y", 100, 100.5, True, "default")
 
 
 def test_injects_prompts():
     some = mock.Mock()
     app = App(inspect.getfile(App))
 
     @app.command(is_unauthenticated=True)
-    def foo(name: str, prompts: Prompts):
+    def foo(name: str, age: int, salary: float, is_customer: bool, prompts: Prompts, address: str = "default"):
         """Some comment"""
         assert isinstance(prompts, Prompts)
-        some(name)
+        some(name, age, salary, is_customer, address)
 
     with mock.patch.object(sys, "argv", [..., FOO_COMMAND]):
         app()
 
-    some.assert_called_with("y")
+    some.assert_called_with("y", 100, 100.5, True, "default")