Custom setting.xml in OpenJDK container build

Solution Verified - Updated

Environment

  • Red Hat OpenShift Container Platform (OCP)
    • 4.X
  • Red Hat build of podman

Issue

  • How to use a custom setting.xml in OpenJDK build?
  • Env variable to use a custom setting.xml in OpenJDK build
  • How to use a custom setting.xml in OpenJDK build?

Resolution

The MAVEN_* environment variables include MAVEN_SETTINGS_XML and MAVEN_OPTS.
For a custom setting.xml use via MAVEN_SETTINGS_XML or the complete settings can be overwritten via MAVEN_OPTS.

For Maven settings see the solution Using Maven parameters on Buildconfig in OCP 4.

If what you want to do is extend the options passed to maven, you can pass additional options (without overriding the ones generated by the S2i script) with MAVEN_ARGS_APPEND.

Auto-generated docs for the environments vars are published here: https://rh-openjdk.github.io/redhat-openjdk-containers/.

Note that the reason that the resulting image, will have the ~/.m2/settings.xml unaffected by MAVEN_SETTINGS_XML due to how S2I works: it runs a build (within which the settings.xml is affected by MAVEN_SETTINGS_XML) and then copies the resulting artifacts out of the builder container instance and into a new image, layered on top of the original builder image. It does not copy ~/.m2/settings.xml as part of that process.

Example

$ s2i --loglevel 5 build SessionReplication/  --environment-file=/path/SessionReplication/.s2i/environment openjdk-pre-build:latest openjdk-session:example
I0204 12:46:47.774396   92895 build.go:52] Running S2I version "unknown"
I0204 12:46:47.774540   92895 util.go:70] Getting docker credentials for openjdk-pre-build:latest
W0204 12:46:48.352851   92895 build.go:167] could not inspect the builder image for labels: reading manifest latest in docker.io/library/openjdk-pre-build: requested access to the resource is denied
I0204 12:46:48.356415   92895 docker.go:491] Using locally available image "docker.io/library/openjdk-pre-build:latest"
I0204 12:46:48.357808   92895 build.go:170] 
Builder Name:            Java Applications
Builder Image:            docker.io/library/openjdk-pre-build:latest
Source:                SessionReplication/
Output Image Tag:        openjdk-session:example
Environment:            
         MAVEN_SETTINGS_XML=/opt/settings.xml
         MAVEN_OPTS=-XX:MaxRAMPercentage=80.0 -XX:+UseG1GC -XX:MinHeapFreeRatio=10 -XX:MaxHeapFreeRatio=20 -XX:GCTimeRatio=4 -XX:AdaptiveSizePolicyWeight=90 -XX:+ExitOnOutOfMemoryError -XX:MaxRAMPercentage=47.3
Environment File:        /home/fdemeloj/Downloads/RedHat/openjdk/SessionReplication/.s2i/environment
...
I0204 12:52:34.364996   94088 sti.go:717] INFO Using MAVEN_OPTS -XX:MaxRAMPercentage=80.0 -XX:+UseG1GC -XX:MinHeapFreeRatio=10 -XX:MaxHeapFreeRatio=20 -XX:GCTimeRatio=4 -XX:AdaptiveSizePolicyWeight=90 -XX:+ExitOnOutOfMemoryError -XX:MaxRAMPercentage=47.3
...
I0204 12:53:03.525305   94088 docker.go:1104] Committing container with dockerOpts: {Reference:openjdk-session:example Comment: Author: Changes:[] Pause:false Config:0xc00032c780}, config: {Hostname: Domainname: User:185 AttachStdin:false AttachStdout:false AttachStderr:false ExposedPorts:map[] Tty:false OpenStdin:false StdinOnce:false Env:[MAVEN_OPTS=-XX:MaxRAMPercentage=80.0 -XX:+UseG1GC -XX:MinHeapFreeRatio=10 -XX:MaxHeapFreeRatio=20 -XX:GCTimeRatio=4 -XX:AdaptiveSizePolicyWeight=90 -XX:+ExitOnOutOfMemoryError -XX:MaxRAMPercentage=47.3 MAVEN_SETTINGS_XML=/opt/settings.xml] 
...
...
...
I0204 12:47:17.706033   92895 postexecutorstep.go:393] Executing step: report success
I0204 12:47:17.706046   92895 postexecutorstep.go:398] Successfully built openjdk-session:example <------------
I0204 12:47:17.706051   92895 postexecutorstep.go:93] Skipping step: remove previous image
...
I0204 12:47:17.732728   92895 fs.go:307] Removing directory '/tmp/s2i1583933938'
I0204 12:47:17.733243   92895 build.go:182] Build completed successfully

Result:

$ docker run --entrypoint=/bin/bash --rm -it  openjdk-session:example
$ cat ./.m2/settings.xml 
<?xml version="1.0" encoding="UTF-8"?>
<settings xmlns="http://maven.apache.org/SETTINGS/1.0.0"
          xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
          xsi:schemaLocation="http://maven.apache.org/SETTINGS/1.0.0 http://maven.apache.org/xsd/settings-1.0.0.xsd">    <!-- ### configured local repository ### -->  <servers>
    <!-- ### configured servers ### -->
  </servers>  <mirrors>
    <!-- ### configured mirrors ### -->
  </mirrors>  <proxies>
    <!-- ### configured http proxy ### -->
  </proxies>  <profiles>

The example above is not supported (s2i stand-alone toolkit is not supported) and the resulting output container image will have the default (from original container image) m2.settings.xml.

Diagnostic Steps

  1. ~/.m2/settings.xml will be the same on the resulting image than the original OpenJDK image.
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