Hello everyone, I'm trying to create dynamically generated assets using dynamic upstream names, the problem is that I can't set a key prefix and a key using assetIn, I'm getting the following error : _key and key_prefix cannot both be set on AssetIn._

from dagster import AssetIn, dagster

########## empty asset

@asset(key_prefix = "PARENT_KEY_PREFIX", group_name="empty")

def empty(context):

return pd.DataFrame([])

@asset(

name = "asset_name",

key_prefix = "key_prefix",

required_resource_keys = {"custom_io_manager"},

io_manager_key = "custom_io_manager",

group_name = "outputs",

ins = {"upstream": AssetIn(key="empty", key_prefix="PARENT_KEY_PREFIX")}

)

def asset_def(context, upstream) -> None:

print("do stuff w/ asset")

return asset_def

Try defining your asset key like this:

AssetIn(key=AssetKey(["PARENT_KEY_PREFIX", "empty"]))

Hi @claire, thanks for you reply. I overcame this issue by defining everything in the key but I was just wondering that adding a param w/ key prefix in AssetIn would add some consistency overall the asset definitions module