upgrading old config fails with unsupported type error

[cpoole]

Expected behavior

my file should correctly parse and update

Actual behavior

parsing fails but file is valid and works if we just manually change the apiVersion.

Information

• Skaffold version: 0.21.0 to 0.22.0
• Operating system: linux - ubuntu 18.04
• Contents of skaffold.yaml:

apiVersion: skaffold/v1beta3
kind: Config
build:
  artifacts:
  - image: local/app1
    context: .
  - image: local/redis-cl
    context: ./redis-local/
deploy:
  helm:
    releases:
    - name: app1
      chartPath: app1
      values:
        image: local/app1
        redisImage: local/redis-cl
      overrides:
        global:
          localstack:
            enabled: true
          environment: "local"
      namespace: "default"
      wait: false
      recreatePods: false

Steps to reproduce the behavior

run skaffold fix and the following is printed:

WARN[0000] config version (skaffold/v1beta3) out of date: upgrading to latest (skaffold/v1beta4) 
FATA[0000] creating runner: parsing skaffold config: transforming skaffold config: converting deploy config: marshalling old: json: unsupported type: map[interface {}]interface {} 

but if I simply update the apiVersion to beta4 it works fine and skaffold is totally happy actually parsing the config

[nkubala]

I think this has actually been broken for a long time. Golang's json package only supports maps with string keys, so the Overrides field in the HelmRelease breaks this because it's a map[string]interface{}.

skaffold/pkg/skaffold/schema/v1beta3/upgrade.go

Lines 68 to 72 in 6a5b206

	func convert(old interface{}, new interface{}) error {
	o, err := json.Marshal(old)
	if err != nil {
	return errors.Wrap(err, "marshalling old")
	}

skaffold fix won't work on any config that has overrides set for helm releases.