Hi, I have a seemingly standard Dockerfile:
# https://hub.docker.com/layers/ocaml/opam/ubuntu-20.04-ocaml-4.13/images/sha256-43d0c6294965bbd51282eb1328c3fd45430a44c4581b7357a9eb4f25731c57cb?context=explore
FROM ocaml/opam:ubuntu-20.04-ocaml-4.13@sha256:43d0c6294965bbd51282eb1328c3fd45430a44c4581b7357a9eb4f25731c57cb as build
RUN sudo apt-get install -y libev-dev libssl-dev libsqlite3-dev pkg-config
WORKDIR zk
ADD . .
RUN opam init
RUN opam exec -- opam install --deps-only -y .
RUN sudo chown -R opam .
RUN opam exec -- dune build --release
# https://hub.docker.com/layers/ubuntu/library/ubuntu/20.04/images/sha256-7c9c7fed23def3653a0da5bc9ecb651efe155ebd5802c7ba5d585edaa6c89496?context=explore
FROM ubuntu:20.04@sha256:7c9c7fed23def3653a0da5bc9ecb651efe155ebd5802c7ba5d585edaa6c89496
WORKDIR /zk
COPY --from=build /home/opam/zk/_build/default/bin/bin.exe ./zk.exe
COPY --from=build /home/opam/zk/css ./css/
COPY --from=build /home/opam/zk/js ./js/
ENV OCAMLRUNPARAM=b
EXPOSE 8080
CMD ["/zk/zk.exe"]
I build it with:
docker build -t zk:latest .
And run with:
docker run zk:latest
However I get an error on run:
standard_init_linux.go:228: exec user process caused: exec format error
I read that this is caused by an arch mismatch, however I chose specific Ubuntu base images after checking they were all Ubuntu 20.04, on linux/amd64. And I’m specifically copying and running the .exe that dune produces, so there should be no issue with that.
Another interesting clue: even the build stage errors when trying to run the same executable it just built:
docker run -it zk-build:latest /bin/sh
$ ls
_build css js migration package.json zk.install zk.opam.template
bin dune-project lib package-lock.json tailwind.config.js zk.opam
$ ./_build/default/bin/bin.exe
/bin/sh: 2: ./_build/default/bin/bin.exe: Exec format error
Any ideas what’s going on?