jib.to.image push to multiple repositories

Environment:

• Jib version: 1.1.2
• Build tool: Gradle v1.1.2
• OS: MacOS

Description of the issue:

Seeking a way to push the same image to multiple image repositories. We have a need where we need to host our images in both DockerHub and ECR, the documentation doesn’t make any reference to if this is possible. If it is in-fact possible, if someone can explain it here, I’d be happy to help update the documentation for the gradle plugin as needed.

Expected behavior:

Allow a means to specify multiple jib.to.image values, such as via a comma separated list, with the expectation that each image provided will be pushed to the correct docker respository.

Steps to reproduce:

1. Create a container repo on dockerhub and ECR
2. Try to push one docker container to both repo’s in one build.

jib-gradle-plugin Configuration:

jib {
	to {
		tags ['latest', 'develop']
		// one possibility:
                image "organization/repo, id.dkr.ecr.us-west-2.amazonaws.com/repo"
		// second possibility:
		image ['organization/repo', 'id.dkr.ecr.us-west-2.amazonaws.com/repo']
    }
}       

Log output:

Caused by: com.google.cloud.tools.jib.image.InvalidImageReferenceException: Invalid image reference: org/repo,id.dkr.ecr.us-east-1.amazonaws.com/repo

— OR —

• What went wrong: Script compilation errors:

  Line 133:         image=listOf("org/repo","id.dkr.ecr.us-east-1.amazonaws.com/repo")
                          ^ Type mismatch: inferred type is List<String> but String? was expected

My log output is from a kotlin gradle buildscript, but I think the concepts apply no matter the buildscript language - there does not appear to be a way to specify 2 image locations to be able to push an image to 2 image repos via one build.

There is a workaround specified here but it feels somewhat un-natural and so I wonder if this tool should support this use case?

[OneCricketeer]

Why not loop and push in a fashion similar to this?

buildCmd -Djib.to.image=foo
buildCmd -Djib.to.image=bar

[chanseokoh]

I wouldn’t worry too much about running Jib multiple times. Everything built for an image is cached and reused (thanks to the strong reproducibility of Jib), so subsequent runs will be no-op regarding building something.