The plugin does not honor the JAVA_HOME I set in ENV directive of Dockfile

Description

The plugin does not honor the JAVA_HOME I set in ENV directive of Dockfile, it replaces it to the JAVA_HOME I set on host machine, for example /Library/Java/JavaVirtualMachines/jdk1.8.0_192.jdk/Contents/Home

Info

• d-m-p version : 0.31.0
• Maven version (mvn -v) :

Maven home: /usr/local/Cellar/maven/3.6.2/libexec
Java version: 1.8.0_192, vendor: Oracle Corporation, runtime: /Library/Java/JavaVirtualMachines/jdk1.8.0_192.jdk/Contents/Home/jre
Default locale: en_US, platform encoding: UTF-8
OS name: "mac os x", version: "10.14.6", arch: "x86_64", family: "mac"

• Docker version :

Client: Docker Engine - Community
 Version:           19.03.3
 API version:       1.40
 Go version:        go1.12.10
 Git commit:        a872fc2
 Built:             Tue Oct  8 00:55:12 2019
 OS/Arch:           darwin/amd64
 Experimental:      false

Server: Docker Engine - Community
 Engine:
  Version:          19.03.3
  API version:      1.40 (minimum version 1.12)
  Go version:       go1.12.10
  Git commit:       a872fc2
  Built:            Tue Oct  8 01:01:15 2019
  OS/Arch:          linux/amd64
  Experimental:     true
 containerd:
  Version:          v1.2.10
  GitCommit:        b34a5c8af56e510852c35414db4c1f4fa6172339
 runc:
  Version:          1.0.0-rc8+dev
  GitCommit:        3e425f80a8c931f88e6d94a8c831b9d5aa481657
 docker-init:
  Version:          0.18.0
  GitCommit:        fec3683

• How to reproduce :

1. Clone the sample project from https://github.com/SgrAlpha/dmp-bug.git
2. Build it using mvn clean package
   • Expected: The build will success
   • Actually: The build failed. If you take a look at <repo>/target/docker/sgrio/sample_webapp/1.0.0-SNAPSHOT/build/Dockerfile, you will see around line 47 the JAVA_HOME variable has been incorrectly replaced to the JAVA_HOME on host machine, but it should use the JAVA_HOME defined here: https://github.com/SgrAlpha/dmp-bug/blob/master/src/main/docker/Dockerfile#L5

• Sample project : https://github.com/SgrAlpha/dmp-bug.git

[rhuss]

Yes, probably. How maybe just that I haven’t set the JAVA_HOME variable locally 😬

It’s just as easy as this: If you have JAVA_HOME set, its broken. If not, the sample works.

So the real problem is, that environment variables are interpolated into a given Dockerfile when copied over into the target directory. I will have to look closer whether this is intentional (e.g. to allow your Dockerfiles to be parameterized) or not.

[paul8620]

Found the issue

public class BuildImageConfiguration implements Serializable {

    public static final String DEFAULT_FILTER = "${*}";

this is where the problem is if you have something like

ENV PATH ${JAVA_HOME}/bin:${PATH}

in your Dockerfile it will substitute the entire line with your PATH switched my ENV line to

ENV PATH $JAVA_HOME/bin:$PATH

and it seems to not do the substitution

@rohanKanojia thanks for suggesting me to fix it otherwise i wouldn’t be able to find the issue. Though i still think the behaviour is buggy with the default filter being what it is

I would considering adding a new feature where the Dockerfile used is not rewritten that would be enabled by a property under <image>

I really consider people using Dockerfiles to be knowledgeable people and also i totally understand the interpolation feature where you want to add build props in the Dockerfile but i believe there are one two many ways to do that.

The proper way to do it is by passing args to Dockerifle and that is less confusing to anyone.

I’ll quit rambling since I fixed my issue thanks again