fix: Remote Online Store Type Inference Error with All-NULL Columns by yuan1j · Pull Request #6063 · feast-dev/feast
When reading features from a Feast Remote Online Store, a TypeError is raised if an entire feature column contains only NULL/NaN values. The error occurs in the python_values_to_proto_values() function when it cannot infer the value type from empty data.
event_timestamp driver_id conv_rate acc_rate avg_daily_trips
0 2026-03-04 16:17:44+00:00 1001 NaN 1.000000 1000.0
1 2026-02-17 16:00:00+00:00 1005 NaN 0.708060 395.0
2 2026-02-17 17:00:00+00:00 1005 NaN 0.451616 145.0
Traceback (most recent call last):
File "C:\svn\project\feature_store\feast\remote\test_workflow.py", line 130, in <module>
run_demo()
File "C:\svn\project\feature_store\feast\remote\test_workflow.py", line 25, in run_demo
fetch_online_features(store)
File "C:\svn\project\feature_store\feast\remote\test_workflow.py", line 121, in fetch_online_features
returned_features = store.get_online_features(
File "C:\Users\j\AppData\Local\Programs\Python\Python310\lib\site-packages\feast\feature_store.py", line 2445, in get_online_features
response = provider.get_online_features(
File "C:\Users\j\AppData\Local\Programs\Python\Python310\lib\site-packages\feast\infra\passthrough_provider.py", line 251, in get_online_features
return self.online_store.get_online_features(
File "C:\Users\j\AppData\Local\Programs\Python\Python310\lib\site-packages\feast\infra\online_stores\online_store.py", line 199, in get_online_features
read_rows = self.online_read(
File "C:\Users\j\AppData\Local\Programs\Python\Python310\lib\site-packages\feast\infra\online_stores\remote.py", line 169, in online_read
message = python_values_to_proto_values(
File "C:\Users\j\AppData\Local\Programs\Python\Python310\lib\site-packages\feast\type_map.py", line 838, in python_values_to_proto_values
raise TypeError("Couldn't infer value type from empty value")
TypeError: Couldn't infer value type from empty value