# ask-ai

Leo Qin

02/21/2024, 4:31 PM
@Scout - i have a situation where an asset is not materializing because it is waiting on a source asset - the source asset by definition can never materialize, how do I resolve this situation?


02/21/2024, 4:31 PM
In the situation where an asset is not materializing because it is waiting on a source asset, and the source asset by definition can never materialize, you may be encountering a discrepancy between the expected behavior of your asset orchestration and the actual behavior of Dagster's asset materialization logic. According to the documentation, a source asset is an asset that has no downstream dependencies within the asset selection and is not expected to be materialized by Dagster. If your asset is waiting on a source asset to materialize, which is not possible, this could indicate a misconfiguration in your asset dependencies or a misunderstanding of how Dagster treats source assets. To resolve this situation, you can consider the following approaches: 1. Review Asset Dependencies: Ensure that your asset's dependencies are correctly defined. If a materializable asset incorrectly depends on a source asset, it may wait indefinitely for a materialization event that will never occur. 2. Update Asset Definitions: If the source asset does actually produce data that should trigger downstream materializations, you might need to redefine it as a materializable asset instead of a source asset. This way, Dagster will expect materialization events for this asset and properly trigger downstream assets. 3. Use Sensors or Hooks: If the source asset is updated externally and you want to trigger materialization of downstream assets when this happens, you can use sensors or hooks to listen for changes and kick off materialization when appropriate. 4. Manual Intervention: As a temporary measure, you could manually materialize the downstream asset if you know that the source asset has been updated and the downstream asset should be refreshed. 5. Debugging and Logs: Utilize Dagster's logging and debugging tools to gain more insight into why the asset is not materializing as expected. This can help you identify any issues with the asset definitions or dependencies. If you have already tried these approaches and the issue persists, it may be helpful to provide more specific details about your asset setup and the behavior you're observing. This could include the asset definitions, how you've configured dependencies, and any relevant logs or error messages. With more context, we can offer more targeted advice or investigate if there's a potential bug or limitation in the current version of Dagster you are using.