[Question] Behaviour when receiving a struct / dataclass

[MrSaints]

We are considering implementing activities in Python, and workflows in Go. When calling activities in Go, it is possible to pass a struct to the activity (e.g. https://github.com/uber-common/cadence-samples/blob/56c4ffffd38e8596075c56f03f82c5a80ae77b92/cmd/samples/fileprocessing/activities.go). We are curious about what the behaviour is like when the activity is implemented using this Python client. Judging from

cadence-python/cadence/conversions.py

Line 125 in 729420c

def json_to_args(jsonb: bytes) -> typing.Optional[list]:

, it seems like the argument will simply be a Python dictionary. If this is the case, are there any plans for automatically converting this to say a Python dataclass?

The use-case for using a single parameter (much like a single message) activity is for versioning. It has been mentioned several times, and the solution seems to always point to this approach for dealing with an activity's contract.

[firdaus]

I missed this requirement. Thanks for bringing this to my attention. At the moment everything becomes a Python primitive, list or dictionary.

I'll add this to 1.1 release. It should be fairly trivial to support as long as the activity method is type annotated.