How do I check whether a particular asset partition is materialized?

[sryza]

How can I check whether a specific partition of an asset is materialized?

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[sryza]

This should work:

from dagster import DagsterInstance, EventRecordsFilter, DagsterEventType, AssetKey


def _is_partition_materialized(
    asset_key: AssetKey, partition_key: str, instance: DagsterInstance
) -> bool:
    return bool(
        instance.get_event_records(
            EventRecordsFilter(
                asset_key=asset_key,
                event_type=DagsterEventType.ASSET_MATERIALIZATION,
                asset_partitions=[partition_key],
            ),
            limit=1,
        )
    )

You can get the instance using context.instance inside any Dagster function that accepts a context object.