git tag contains "/" causes docker build failure

[zhuming]

Expected behavior

• Any valid Dockerfile
• git tag name contains "/"
• run skaffold build
  --> expect the image is built and tagged properly

Actual behavior

skaffold build fails with error message

Generating tags...
 - my-docker-repositories.com/helloworld/hw -> cxm-my-docker-repositories.com/helloworld/hw:ms/1.0.0-94-g93057a3
Checking cache...
 - my-docker-repositories.com/helloworld/hw: Not found. Building
Building [my-docker-repositories.com/helloworld/hw]...
FATA[0001] failed to build: build failed: build failed: building [my-docker-repositories.com/helloworld/hw]: build artifact: docker build: Error response from daemon: invalid reference format

Information

• Skaffold version: version... 0.6.0 and 1.0.0
• Operating system: ... MacOS
• Contents of skaffold.yaml:

apiVersion: skaffold/v1
kind: Config
build:
  artifacts:
  - image: my-docker-repositories.com/helloworld/hw
    context:
      .
deploy:
  kubectl:
    manifests:
    - k8s/hw-dev.yaml

Steps to reproduce the behavior

1. clone any repo
2. git tag tag/slash
3. skaffold build

[zhuming]

Please either make the error message more clear, or replace all invalid character when generating the docker image tag from a git tag. Thanks.

[tejal29]

@zhuming Thank you filing the bug. Replacing all invalid characters seems a good solution. Would you be up for submitting a PR?

Here is where we get the tag name https://github.com/GoogleContainerTools/skaffold/blob/master/pkg/skaffold/build/tag/git_commit.go#L77

we can add a function replaceInvalidChars and check if generated ref contains / and replace them with `_' or throw an error.