@Marvin have you ever seen the following error:

Downloading flow code from storage at None

? This is happening in an ecs based flow, with a custom built docker image.

It seems I had a bit of a hiccup while trying to fetch relevant information from the Prefect Docs and GitHub issues. My apologies for that! However, based on my past experiences, the error message "Downloading flow code from storage at None" typically indicates an issue with the flow's storage configuration not being set properly in ECS with a custom Docker image. Here are a few things you can check which might help resolve this issue: 1. Verify Storage Configuration: Ensure that the storage is correctly configured within your Prefect flow definition. This error could occur if the flow's

storage

attribute isn't set up properly. 2. Environment Variables: Make sure that the necessary environment variables are set and available in your ECS environment. Sometimes missing environment variables can cause issues in retrieving the flow code. 3. Permissions and Dockerfile: If you're using a custom Docker image, double-check the Dockerfile for any operations or permissions that might be affecting the access to flow storage. 4. Docker Image Compatibility: Ensure your custom Docker image is compatible with the execution environment, including Python and any required dependencies. If these steps don't resolve the issue, I would recommend checking Prefect's discussion forums or trying a different storage option to see if the issue persists. If you have any more information about your Prefect version or errors, feel free to share!

@Marvin where is flow storage configured in the UI?

Configuring flow storage in Prefect isn't done directly through the UI. The flow storage is typically specified during the deployment process using the CLI or a configuration file like a

prefect.yaml

file. Here's how you can approach it based on the version you might be using: 1. Prefect 2.x: - Storage can be configured using the

prefect deploy

CLI command interactively or specified in a

prefect.yaml

file. Options can include Git-based storage, cloud provider storage (e.g., S3, GCS), or Docker image-based storage. - You can specify the flow code storage during the interactive CLI experience of

prefect deploy

. Reference: Storage Blocks in Prefect 2.x 2. Prefect 3.x: - Again, storage isn't configured in the UI but rather in your YAML configuration or during deployment creation via the CLI with options for Git, cloud storage, or Docker images. - You can create a deployment using either the Python deploy method or via a

prefect.yaml

file interactively, specifying the storage using the

flow.from_source

method if needed. Reference: Storage Guide in Prefect 3.x Given these configurations, ensure your flow's storage option is appropriate for your deployment setup. If there's anything else you'd be curious about, just let me know. I'm here to help, and no, unfortunately, I don't come with a jovial user interface myself!

I had

WORKDIR /opt/prefect/flows

instead of

WORKDIR /opt/prefect/flows/

in my custom docker file.