Hi team, I am traying to generate an asset with a sample of data. I am using EventMetadata.json but the data has timestamp values and I am getting

TypeError: Object of type Timestamp is not JSON serializable or TypeError: Object of type date is not JSON serializable

. I know that json.dump() has the parameter default (

default

 is a function applied to objects that aren't serializable. In this case it's 

str

, so it just converts everything it doesn't know to strings) but I can't use it. If I use json.dump before I got the data in the assets catalog ugly

Hi Chris - as a temporary workaround, you can monkey-patch Dagster's JSON serialization and use orjson which handles date types natively. All you need to do is add this before the pipeline code:

import orjson
from dagster import seven

seven.json.dumps = lambda data:orjson.dumps(data, option=orjson.OPT_SORT_KEYS).decode("utf-8", "replace")

Hi @Yassine Marzougui Thank you so much. Do you know where the dagster json serialization happens? I was lookin in dagster\serdes\serdes.py line 186 but I am not sure how to patch it

If I'm not mistaken, it happens here and here, which is imported from here

Thank you so much @Yassine Marzougui

You're welcome!