Using base image from other namespace did not work

[henrjk]

Describe the bug
I experimented with using a base image created in openshift and then referencing this in the buildConfig as follows:

- apiVersion: build.openshift.io/v1
  kind: BuildConfig
...
  spec:
     strategy:
       dockerStrategy:
         from:
           kind: ImageStreamTag
           name: 'be-python-flask-base:${BASE_TAG}'
          namespace: example-cd
       type: Docker

However during the shared library buildArgs patch created in

ods-jenkins-shared-library/vars/stageStartOpenshiftBuild.groovy

Line 106 in a7ff00a

def buildArgsPatch = """{"op": "replace", "path": "/spec/strategy/dockerStrategy", "value": {"buildArgs": [

replaces the entire dockerStrategy and this removes the from information.

As a consequence the image was attempted to be loaded from the docker registry instead of the internal registry which failed.

I'd be happy to work on a fix unless there was some known reason that a more targeted patch would not work.

To Reproduce
I don't have something I can share ready. Please ask if clarification is needed.

Expected behavior
The patch should only add build args and leave other pieces of the dockerStrategy alone.

Affected version (please complete the following information):

• OpenShift:3.11
• OpenDevStack master

[michaelsauter]

I don't see a major reason why the more targeted approach would not work. One reason that the whole thing was updated may be that - IIRC - a replace operation also adds the entry if it does not exist. Please check. However, even if this is the case, I would support going to the narrower approach as it gives you the functionality needed, and has fewer surprises. We would only need to document this "breaking" change - which is breaking in theory, but no users should be affected by it ...

[michaelsauter]

@henrjk Looking at this again, the issue should ONLY happen if you pass custom buildArgs. Are you doing this actually?

[henrjk]

This happed with the following in Jenkinsfile:

odsPipeline(
...
  stageStartOpenshiftBuild(context, [nexusHostWithBasicAuth: context.nexusHostWithBasicAuth, nexusHostWithoutScheme: context.nexusHost.tokenize('//')[1]])

which ultimately stems from here:

https://github.com/opendevstack/ods-quickstarters/blob/7f8c371a14e3c1dd64c48dcbad404f3949b11350/be-python-flask/Jenkinsfile.template#L34

[michaelsauter]

@henrjk Right, this is the default Python Jenkinsfile. For other quickstarters, the issue is not triggered because other quickstarters do not use the buildArgs.

Now it makes sense to me why I was sure it was working while you were sure it was not working :D