Support for integer keys

[sleepycat]

Attempting to build Knative config with 3.9.0 on Manjaro Linux produces the error Error: json: unsupported type: map[interface {}]interface {}.

[mike@ouroboros minikube]$ kustomize version
{Version:3.9.0 GitCommit:$Format:%H$ BuildDate:2020-12-13T07:57:44Z GoOs:linux GoArch:amd64}
[mike@ouroboros minikube]$ cat kustomization.yaml 
apiVersion: kustomize.config.k8s.io/v1beta1
kind: Kustomization
resources:
- https://github.com/knative/serving/releases/download/v0.19.0/serving-core.yaml
[mike@ouroboros minikube]$ kustomize build .
Error: json: unsupported type: map[interface {}]interface {}

Kustomize 3.8 will successfully build.

[mike@ouroboros minikube]$ kustomize version
{Version:kustomize/v3.8.8 GitCommit:72262c5e7135045ed51b01e417a7e72f558a22b0 BuildDate:2020-12-10T18:05:35Z GoOs:linux GoArch:amd64}
[mike@ouroboros minikube]$ kustomize build .
apiVersion: v1
kind: Namespace
metadata:
  labels:
    serving.knative.dev/release: v0.19.0
  name: knative-serving
---
apiVersion: apiextensions.k8s.io/v1
kind: CustomResourceDefinition
metadata:
  labels:
    knative.dev/crd-install: "true"
    serving.knative.dev/release: v0.19.0
  name: certificates.networking.internal.knative.dev
...

[Shell32-Natsu]

We have issues in 3.9.0. Please try 3.9.1.

[stefanprodan]

@Shell32-Natsu can you shed some light on this? I'm using sigs.k8s.io/kustomize/api v0.7.1 in fluxcd/kustomize-controller but this bug is still there.

I find it very hard to keep up with kustomize upstream changes, there is no changelog expect for a list of commits. For Flux users is even harder, with error outputs like json: unsupported type: map[interface {}]interface {} it's impossible to track down which object from all the manifests caused this.

[echel0n]

This issue is still present in API v0.7.2 as well

[stefanprodan]

This turns out to be a bug in kyaml, here is how to reproduce it.

Having a custom resource with an integer key:

apiVersion: helm.toolkit.fluxcd.io/v2beta1
kind: HelmRelease
metadata:
  name: podinfo
spec:
  interval: 5m
  chart:
    spec:
      chart: podinfo
      sourceRef:
        kind: HelmRepository
        name: podinfo
  values:
    tcp:
      8080: "default/example-tcp-svc:9000"

Fails with:

$ kustomize build
Error: error marshaling into JSON: json: unsupported type: map[interface {}]interface {}

Works with:

kustomize build --enable_kyaml=false

Version:

kustomize version
{Version:kustomize/v3.9.2 GitCommit: BuildDate:2021-01-17T19:01:12+00:00 GoOs:darwin GoArch:amd64}

What I find really concerning is that users have no way to identify the object/resource/file when kustomize build fails. @Shell32-Natsu what is the recommend way to debug this when you have hundreds of manifests?