How to parse a JSON secret to YAML in Vault? - kubernetes

Question

I have a secret in Vault which is really a "complex" structure of JSON, meaning it's not just a key/value but there are several keys at different sublevels.
I need to somehow get this secret and convert it to the YAML representation of that JSON. If it was a simple structure (like several k/v at the same level), I could use something as simple as
{{- with secret "secret/foo" -}}
{{ range $k, $v := .Data.data }}
{{ $k }}: {{ $v }}
{{- end }}
{{- end }}
however, as this is not the case, and the structure of the JSON is complex, trying to come up with a template is rather impossible.
However, I found that Vault uses Consul templates, and Consul has a parseYAML function, so my question is, how can I template this so that I get all the content of .Data.data and translate it into YAML?
I have tried several approaches similar to this one below:
{{- with secret "secret/foo" -}}
{{ .Data.data| parseYAML }}
{{- end }}
but I'm always getting the same error wrong type for value; expected string; got map[string]interface {}"
UPDATE
Sample yaml:
apiVersion: v1
kind: ServiceAccount
metadata:
name: app
---
apiVersion: apps/v1
kind: Deployment
metadata:
name: app
spec:
selector:
matchLabels:
app: app
template:
metadata:
labels:
app: app
annotations:
vault.hashicorp.com/agent-inject: 'true'
vault.hashicorp.com/agent-inject-secret-foo: 'secret/foo'
vault.hashicorp.com/agent-inject-template-secret-foo: |
{{- with secret "secret/foo" -}}
{{ .Data.data| parseYAML }}
{{- end }}
vault.hashicorp.com/role: 'app'
spec:
containers:
- name: app
image: 'app:1.0.0'
serviceAccountName: app
where secret/foo is a long JSON with no clear structure. A random example (actual JSON is about 300 lines I think).
{
"a": {
"a": "a",
"b": "b",
"c": {
"a": "a",
"b": {
"c": "c"
},
"d": "a"
},
"e": {
"a": {
"b": {
"c": {
"a": "a",
"b": "b"
}
}
}
}
}
}

Answer 1

Ok, just figure this out.
{{- with secret "secret/foo" -}}
{{ .Data.data| toYAML }}
{{- end }}
this is correct, but instead of parseYAML the right function is toYAML.