Passing in duplicate buildargs

Please pardon this "support" type request, but reading the docs, and the source code (namely https://github.com/docker/docker-py/blob/master/docker/api/build.py) I didn't see a way to do this.

For the "buildargs" dict passed to image.build, how do you support build arguments which can be given more than once? For example, the --secret parameter documented here: https://docs.docker.com/develop/develop-images/build_enhancements/#new-docker-build-secret-information

You can specify --secret more than once on the command line, with different values each time. Code:

echo 'WARMACHINEROX' > mysecret.txt
echo 'WARMACHINEROX2' > mysecret2.txt

export DOCKER_BUILDKIT=1

cat <<EOF > Dockerfile
FROM alpine

# shows secret from default secret location:
RUN --mount=type=secret,id=mysecret cat /run/secrets/mysecret
RUN --mount=type=secret,id=mysecret2 cat /run/secrets/mysecret2
EOF

docker build --no-cache --progress=plain --secret id=mysecret,src=mysecret.txt --secret id=mysecret2,src=mysecret2.txt .

produces:

<snip>
#9 [2/5] RUN --mount=type=secret,id=mysecret cat /run/secrets/mysecret
#9 0.500 WARMACHINEROX
#9 DONE 0.6s

#10 [3/5] RUN --mount=type=secret,id=mysecret2 cat /run/secrets/mysecret2
#10 0.560 WARMACHINEROX2
#10 DONE 0.6s
<snip>

How might I go about passing in both arguments?

From reading the code, it does not appear this will work:

buildargs[secret] = ['id=mysecret,src=mysecret.txt', 'id=mysecret2,src=mysecret2.txt']

Ideas? Suggestions?

Thanks!

Start with docker/api/build.py and the image.build buildargs handling, then compare it with Docker's documented repeated --secret options and the Docker Engine API representation. Done means the supported input for multiple build arguments is established and verified against the example behavior; no test file is named in the issue.