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COPY --chown fails in automated build: "Unknown flag: chown"

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automatedbuilds
dockercloud

(Mbdevpl) #1

Hello, I’m using Docker Cloud automated builds feature on few repos, and in general it’s working without issue… However, I have this one Dockerfile, which builds fine on my machine, but fails when building on Docker Cloud, when using the command:

COPY --chown=user:user . /home/user/Projects/transpyle

with error:

Unknown flag: chown
ERROR: Build failed: Unknown flag: chown
ERROR: Build failed with exit code 2
ERROR: Build in 'ubuntu16.04' (de879021) failed in 0:08:38

Full log here:

https://cloud.docker.com/app/mbdevpl/repository/registry-1.docker.io/mbdevpl/transpyle/builds/322f3b42-4110-469b-bd40-ad84a5853ae6

Is Docker on Docker Cloud outdated or something? On my local machines (Ubuntu and Mac) I’m using up to date Docker, and I’m not facing any issues like that.


(Sam) #2

the doc for COPY doesn’t mention --chown


(Mbdevpl) #3

Indeed the docs don’t mention it. However it exists in Docker since version 17.09:

And I’m using 17.09 on my computers.

It looks like both docker on Docker Cloud and the docs are outdated…


(Mbdevpl) #4

Oh well… I changed my command:

COPY --chown=user:user . /home/user/Projects/transpyle

Into the more verbose legacy version:

COPY . /home/user/Projects/transpyle
RUN sudo chown -R user:user /home/user/Projects/transpyle

And now it works also on the cloud. Maybe one day they’ll update it too :confused:


(Jjaekel) #5

Docker Cloud service has still the issue.

Step 17/24 : COPY --from=logstash --chown=1000:1000 /target /usr/share/logstash

Unknown flag: chown

https://hub.docker.com/r/ergomentum/logstash/builds/b7gwbkfeatgvlikhylgnrl6/

The workaround mentioned above does not work if chown is not available in the image :confused: Any chance to update?


(Sam) #6

Install chown into the image if u need it