Sorry, I'm still confused around blocks! I understand that I might want to add a block in order to centrally coordinate access to configuration inside my flow. At this point, I'm just trying to get my flow running though, using an ECS-Task block. 1. I've defined a block in Python with

ECSTask(...).save("dev-trial", overwrite=True)

on my dev machine. It shows up in Prefect Cloud. 2. I have created a deployment with

prefect deployment build -n dev-trial -q dev -ib ecs-task/dev-trial -a flows/healthcheck.py:healcheck

again from my dev machine 3. I have started a local agent with

prefect agent start -q dev

and triggered a job. All works. 4. I have started an agent inside a container and triggered the job, but now it fails with the error

KeyError: "No class found for dispatch key 'ecs-task' in registry for type 'Block'."

It seems like in the container, it's not able to resolve the block reference. But isn't that embedded inside the yaml downloaded from Prefect Cloud?

^ Yep. If

prefect-aws

isn’t installed, the implementation of the block will not be discoverable.

...

I've worked around it by adding the installation to the entrypoint command

yeah, we'll work around it.. i would just assume the docker image prefect says to run as the aws ecs fargate agent would have the prefect-aws module lol

We do not include collections in our base images because otherwise we’d need all the cloud-providers installed which is really heavy.