docker-compose.yml does not work on m1 macs

[Christewart]

Tested on 0a0fc92

Here is the corresponding docker image

https://hub.docker.com/layers/227603796/bitcoinscala/bitcoin-s-server/1.9.1-75-0a0fc92f-SNAPSHOT/images/sha256-60861248ea4c099877fa04fee732332e4e6640d1ef7de57cdf79d4a9d042eda9?context=repo

The image constantly says "No java detected"

My am64 linux machine works fine on the same docker image.

[Christewart]

So ran an image to get access to the filesystem on the container, and attempted to run ./jre/bin/java -version to see if java can run and ran into this error:

From a quick google, this means the jre is incompatible with the underlying chip architecture.

https://mkyong.com/java/bash-usr-bin-java-cannot-execute-binary-file-exec-format-error/

I don't really understand how this can be the case though as I built this image locally on my m1 mac and am attempting to run it locally on m1 mac. jlink should be fetching from a aarch64 jre.

For remotely built images, this is likely an issue as I'm guessing CI machines are x86, which means the jre built by jlink would also be x86.

bitcoin-s@d672864e1b18:/opt/docker$ ./jre/bin/java
bash: ./jre/bin/java: cannot execute binary file: Exec format error

[Christewart]

Posted a SO question to hopefully get some help: https://stackoverflow.com/questions/72521555/arm64-docker-image-built-on-arm64-machine-m1-does-not-create-java-runtime-corr

[Christewart]

This seems to be the root cause, the runtime linker used by jlink is not available in the docker image. The suggested workaround is to containerize the build process so that there is not differences between the build machine and the docker image

https://stackoverflow.com/a/63595415/967713

[Christewart]

So the problem seems to be that the jre is expecting the linker /lib64/ld-linux-x86-64.so.2 to be available to it. Since this is not available, the java runtime fails immediately

On x86 machine this linker does exist which is why java starts

[Christewart]

Unfortunately it seems that linux/arm64 runners are not likely to come to github actions anytime soon: actions/runner-images#2536

It also doesn't look like native m1 support will be added to github actions anytime soon:

actions/runner-images#2187

[Christewart]

Summary

Building jre with jlink outside of the docker image and copying it inside

This fails because the jre is now built with x86 specific linkage. When we go to run java it fails because it cannot find the x86 linker. See this comment

Containerizing building the jre inside of both arm64/x86 docker containers

This cannot work on github actions because MS does not allow arm64 runners on github actions. This means we cannot natively run the arm64 build container on to properly build the arm64 docker runtime.

Path forward

I think the only path forward is to build with openjdk (essentially revert #4367) docker images and disable the jlink plugin somehow on docker builds.

Unfortunately this also means our normal zip build for m1 macs will have the same problem. We will have to ask the user to install java if they are using an m1 mac.

[Christewart]

Documentation on how to self host github runners: https://docs.github.com/en/actions/hosting-your-own-runners/about-self-hosted-runners

[Christewart]

Docker portion is fixed, native m1 mac is now tracked by this issue: #4383