helm-template get value of the map by key - kubernetes-helm

Question

In the helm-template I'm trying to retrieve a value of the map by key.
I've tried to use the index from the go-templates, as suggested here:
Access a map value using a variable key in a Go template
However it doesn't work for me (see later test). Any idea for the alternative solution?
Chart.yaml:
apiVersion: v1
appVersion: "1.0"
description: A Helm chart for Kubernetes
name: foochart
version: 0.1.0
values.yaml:
label:
- name: foo
value: foo1
- name: bar
value: bar2
templates/test.txt
label: {{ .Values.label }}
Works OK for helm template .:
---
# Source: foochart/templates/test.txt
label: [map[value:foo1 name:foo] map[name:bar value:bar2]]
However once trying to use the index:
templates/test.txt
label: {{ .Values.label }}
foolabel: {{ index .Values.label "foo" }}
It won't work - helm template .:
Error: render error in "foochart/templates/test.txt": template: foochart/templates/test.txt:2:13: executing "foochart/templates/test.txt" at <index .Values.label ...>: error calling index: cannot index slice/array with type string

Answer 1

label is an array, so the index function will only work with integers, this is a working example:
foolabel: {{ index .Values.label 0 }}
The 0 selects the first element of the array.
A better option is to avoid using an array and replace it with a map:
label:
foo:
name: foo
value: foo1
bar:
name: bar
value: bar2
And you dont even need the index function:
foolabel: {{ .Values.label.foo }}

Answer 2

values.yaml
coins:
ether:
host: 10.11.0.50
port: 123
btc:
host: 10.11.0.10
port: 321
template.yaml
{{- range $key, $val := .Values.coins }}
apiVersion: apps/v1
kind: Deployment
metadata:
name: {{ $key }}
- env:
- name: SSH_HOSTNAME
value: {{ $val.host | quote }}
- name: SSH_TUNNEL_HOST
value: {{ $val.port | quote }}
---
{{- end }}
run $ helm template ./helm
---
# Source: test/templates/ether.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
name: btc
- env:
- name: SSH_HOSTNAME
value: "10.11.0.10"
- name: SSH_TUNNEL_HOST
value: "321"
---
apiVersion: apps/v1
kind: Deployment
metadata:
name: ether
- env:
- name: SSH_HOSTNAME
value: "10.11.0.50"
- name: SSH_TUNNEL_HOST
value: "123"
---