When trying to build my flow (docker storage) with

prefect build

I am running into an error

mkdir: cannot create directory '/opt/prefect/': Permission denied

- I am creating a user in my Dockerfile thru

useradd

it appears there are extra commands prefect appends to the user defined Dockerfile - is the root user required?

@Leon Kozlowski can you share your Dockerfile?

I can’t share the entire dockerfile but the useradd bit looks like this

RUN useradd <name_of_user>

WORKDIR /home/<name_of_user>

RUN chown <name_of_user> /home/<name_of_user>

USER <name_of_user>

in general, if you specify the user after you set all the copying files and preparing environment, this should work fine. Example:

FROM python:3.9-slim-bullseye
COPY requirements.txt .
RUN pip install -r requirements.txt
COPY src/ .
USER 1000:1000
CMD ["python", "your_script.py"]

im using the prefect0.14.19-python3.8 as a builder

So you use Docker storage? what you shared is basically adding health checks that ensure that your flow is serializable. You should be able to avoid the error you mentioned if you put the USER command near the end, because this user would only be defined for the process executing the flow run, rather than the process building the environment for the flow run

The user commands are at the end of my docker file - the

RUN mkdir -p /opt/prefect/

happens afterwards

I’d say that you don’t need any of this, i.e. neither the mkdir /opt/prefect/, nor prefect build, because when you register your flow, the Docker storage gets built anyway. But if you need those commands, then move them before the USER command:

RUN mkdir -p /opt/prefect && prefect build
USER 1000:1000

the commands arent even in my dockerfile

It seems like you want to have more control over the build process? if that’s the case, perhaps you can build the image independently on your own and pass it to DockerRun/KubernetesRun/ECSRun, and on registration not building the storage? Here is an example you could use. This way, whatever USER or image you choose, the Prefect’s storage.build() process won’t complain because you’re building the image on your own. You could use it as follows:

if __name__ == "__main__":
    docker_storage.add_flow(flow)
    flow.register(project_name="community", build=False)

I didnt know building and pushing the image independently was an option - this is very helpful

Hey @Anna Geller I'd like to know what build=False does ? Do you mind expanding on that ?

flow.register(project_name="community", build=False)

@Tilak Maddy it registers a flow without building the Docker storage