feat(alpine-jdk8) switch base image from deprecated adoptopenjdk to eclipse-temurin (adoptium)

[dduportal]

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[dduportal]

Good! the test are failing as described by @MarkEWaite in #118 . Gotta diagnose now.

[dduportal]

Ok, the change of base image introduce the following test failure (only 1):

#11 [docker.io/jenkins/ssh-agent:alpine-jdk8] has utf-8 locale – jenkinsci.docker.alpine_jdk8.Default

which is this test:

https://github.com/jenkinsci/docker-ssh-agent/blob/master/tests/tests.bats#L187-L194

[dduportal]

The adoptopenJDK image defined the UTF-8 locale in 2 different places:

• With the environment variables LANG and LC_ALL in https://github.com/AdoptOpenJDK/openjdk-docker/blob/master/8/jdk/alpine/Dockerfile.hotspot.releases.full#L22
• With the localdef command associated to the glibc (which is a "hack" in a musl-linux distribution such as Alpine, but a mandatory hack to allow JDK to behave as expected: it is outside our scope) in https://github.com/AdoptOpenJDK/openjdk-docker/blob/master/8/jdk/alpine/Dockerfile.hotspot.releases.full#L40 (command /usr/glibc-compat/bin/localedef --force --inputfile POSIX --charmap UTF-8 "$LANG" || true)

[dduportal]

On the temurin image, only the environment variables are used: https://github.com/adoptium/containers/blob/087b411c6bb456e4c2a417aa358e6ff81d5775c4/8/jdk/alpine/Dockerfile.releases.full#L22.

=> That explains the root cause of the test failing.
=> Now we have to take a decision by comparing to other Jenkins agent images + Jenkins controller images (as they all use temurin): do we need to change the test to only check the environment variable, or do we need to run the localedef command on our own

[dduportal]

Please note that temurin relies on the native musl localedef: https://github.com/adoptium/containers/blob/087b411c6bb456e4c2a417aa358e6ff81d5775c4/8/jdk/alpine/Dockerfile.releases.full#L24 . Sounds like good enough

[dduportal]

• For the docker-agent image (acting as a base image for inbound agent), we only test the result of the charmap command (and only environment variables are used): https://github.com/jenkinsci/docker-agent/blob/fa7d7a5649a1502ba946a74eec0869bdb6284fbb/tests/tests.bats#L30-L33
• For the docker-inbound-agent, we do test or specify anything: https://github.com/jenkinsci/docker-inbound-agent/search?q=utf-8
• For the controller image:
  • Tests are using different commands if using alpine or not: https://github.com/jenkinsci/docker/blob/f5b6308d9ac3b549f1fd352027ac9f8d47b5a4b7/tests/runtime.bats#L67-L74
  • We do call the localdef command from glibc, likewise the former adoptopenjdk, but only for alpine JDK11: https://github.com/jenkinsci/docker/blob/f69ada61dd7fc566fd4395aa9548a2d2e15abf6d/11/alpine/hotspot/Dockerfile#L67

[MarkEWaite]

I've merged #118. Apologies for the conflicts but most sincere thanks for applying your skills to the failing tests!

[dduportal]

PR ready for review: tests are now passing \o/

[MarkEWaite]

That's great! Removed a special case in the test and switched to use a supported and maintained distribution in the Docker image.