If docker.image.tag is set to a placeholder, we should replace it.

[henri-tremblay]

Fix #1468
This occurs when docker.image.name is constructed with ${docker.image.repo}:${docker.image.tag}.

This is a fix to #1468

[henri-tremblay]

Note: It is undocumented that docker.image.tag can override %l. So if I do mvn docker:build -Ddocker.image.name=%a:%l -Ddocker.image.tag=nightly I will end up with myapp:nightly

[codecov]

Codecov Report

Merging #1469 (7a29f39) into master (61e0cc7) will increase coverage by 0.02%.
The diff coverage is 100.00%.

❗ Current head 7a29f39 differs from pull request most recent head 390b3d3. Consider uploading reports for the commit 390b3d3 to get more accurate results

@@             Coverage Diff              @@
##             master    #1469      +/-   ##
============================================
+ Coverage     61.94%   61.97%   +0.02%     
- Complexity     2149     2150       +1     
============================================
  Files           166      166              
  Lines          9484     9488       +4     
  Branches       1441     1439       -2     
============================================
+ Hits           5875     5880       +5     
+ Misses         3095     3093       -2     
- Partials        514      515       +1     

Impacted Files	Coverage Δ	Complexity Δ
.../fabric8/maven/docker/util/ImageNameFormatter.java	95.83% <100.00%> (+1.71%)	11.00 <0.00> (ø)
...8/maven/docker/config/BuildImageConfiguration.java	81.25% <0.00%> (ø)	88.00% <0.00%> (ø%)

[rohanKanojia]

@henri-tremblay: Thanks a lot for the PR. Could you please add a line to doc/changelog.md regarding this change?

Note: It is undocumented that docker.image.tag can override %l. So if I do mvn docker:build -Ddocker.image.name=%a:%l -Ddocker.image.tag=nightly I will end up with myapp:nightly

Shall we document this behavior in this PR or in separate PR?

[henri-tremblay]

Done for the changelog. You should really generate the change log from the issues in the release. I'm doing something similar here: https://github.com/easymock/easymock/blob/master/generate-changelog.sh.

I will let you update the documentation in another PR. From my reading of ImageNameFormatter, two parameters are special. docker.image.user and docker.image.tag. Both can be passed in parameter to override the %g and %v %t %l.