将YAML字符串转换为Helm模板中的dict

Question

I am creating a chart for a project that has a binary that when executed generates a configuration file in YAML format that looks like this:

---
PARAM_1: value1
PARAM_2: value2

My chart needs to read this file and and load all of its values into environment variables in a container, so I created a variable config in my values.yaml file and when the chart is installed I am passing the file content using --set-file:

helm install <CHART> --set-file config=/path/to/yaml/config/file

Next I create a ConfigMap withe the value of .Values.config:

apiVersion: v1
kind: ConfigMap
metadata:
  ...
data:
  {{ .Values.config }}

The problem I am having is that I need to do two things with values of config:

• prefix all keys with a predefined value (so in the example above I would MY_APP_PARAM_1 as key)
• make sure the values are all string, otherwise the ConfigMap will fail

How can I parse the value of .Values.config in my template as a dict so that I can use a range loop do these changes?

Answer 1

In the end I was able to do something like this:

{{ $lines := splitList "
" .Values.config -}}
{{- range $lines }}
{{- if not (. | trim | empty) -}}
{{- $kv := . | splitn ":" 2 -}}
{{ printf "MY_APP_%s: %s" $kv._0 ($kv._1 | trim | quote) | indent 2 }}
{{ end -}}
{{- end -}}

I had a hard time getting the {{- vs {{ right, and helm install --debug --dry-run . help a lot in this part.

It's kind of messy, so I would be very interested in seeing if anyone has a better solution.