Hello! Is there something wrong with running deployments from CLI without parameters (Prefect 2.16.3)? For example if I deploy this flow:

@flow(log_prints=True)
def hello_flow(foo: str = "bar"):
    print(f"Hello, {foo}!")

And try to run it with:

prefect deployment run 'hello_flow/my_deployment'

I get this error:

File "/Users/user/project/.venv/lib/python3.11/site-packages/prefect/cli/deployment.py", line 1698, in _load_json_key_values
    for spec in cli_input:
TypeError: 'NoneType' object is not iterable

But this works just fine:

prefect deployment run 'hello_flow/my_deployment' --param foo="baz"

Also if I create flow without parameters (just print "Hello world" for example) there is no way to run the deployment as it doesn't accept any parameters and always gives the error above.

Hi Marko! I found this issue that looks related: https://github.com/PrefectHQ/prefect/issues/12397 I suggest running

pip install 'typer<0.10.0'

and seeing if that resolves the issue

Yup that worked, thanks 🙂