Data is empty when accessing config file in k8s configmap with Helm - kubernetes

Question

I am trying to use a configmap in my deployment with helm charts. Now seems like files can be accessed with Helm according to the docs here: https://github.com/helm/helm/blob/master/docs/chart_template_guide/accessing_files.md
This is my deployment:
kind: Deployment
apiVersion: extensions/v1beta1
metadata:
name: "{{ template "service.fullname" . }}"
labels:
chart: "{{ .Chart.Name }}-{{ .Chart.Version }}"
spec:
replicas: {{ .Values.replicaCount }}
template:
metadata:
labels:
app: "{{ template "service.fullname" . }}"
spec:
containers:
- name: "{{ .Chart.Name }}"
image: "{{ .Values.registryHost }}/{{ .Values.userNamespace }}/{{ .Values.projectName }}/{{ .Values.serviceName }}:{{.Chart.Version}}"
volumeMounts:
- name: {{ .Values.configmapName}}configmap-volume
mountPath: /app/config
ports:
- containerPort: 80
name: http
livenessProbe:
httpGet:
path: /health
port: http
initialDelaySeconds: 10
timeoutSeconds: 5
readinessProbe:
httpGet:
path: /health
port: http
initialDelaySeconds: 10
timeoutSeconds: 5
volumes:
- name: {{ .Values.configmapName}}configmap-volume
configMap:
name: "{{ .Values.configmapName}}-configmap"
My configmap is accessing a config file. Here's the configmap:
apiVersion: v1
kind: ConfigMap
metadata:
name: "{{ .Values.configmapName}}-configmap"
labels:
app: "{{ .Values.configmapName}}"
data:
{{ .Files.Get "files/{{ .Values.configmapName}}-config.json" | indent 2}}
The charts directory looks like this:
files/
--runtime-config.json
templates/
--configmap.yaml
--deployment.yaml
--ingress.yaml
--service.yaml
chart.value
vaues.yaml
And this is how my runtime-confi.json file looks like:
{
"GameModeConfiguration": {
"command": "xx",
"modeId": 10,
"sessionId": 11
}
}
The problem is, when I install my chart (even with a dry-run mode), the data for my configmap is empty. It doesn't add the data from the config file into my configmap declaration. This is how it looks like when I do a dry-run:
---
apiVersion: v1
kind: ConfigMap
metadata:
name: "runtime-configmap"
labels:
app: "runtime"
data:
---
kind: Deployment
apiVersion: extensions/v1beta1
metadata:
name: "whimsical-otter-runtime-service"
labels:
chart: "runtime-service-unknown/version"
spec:
replicas: 1
template:
metadata:
labels:
app: "whimsical-otter-runtime-service"
spec:
containers:
- name: "runtime-service"
image: "gcr.io/xxx-dev/xxx/runtime_service:unknown/version"
volumeMounts:
- name: runtimeconfigmap-volume
mountPath: /app/config
ports:
- containerPort: 80
name: http
resources:
limits:
cpu: 100m
memory: 100Mi
requests:
cpu: 100m
memory: 100Mi
livenessProbe:
httpGet:
path: /health
port: http
initialDelaySeconds: 10
timeoutSeconds: 5
readinessProbe:
httpGet:
path: /health
port: http
initialDelaySeconds: 10
timeoutSeconds: 5
volumes:
- name: runtimeconfigmap-volume
configMap:
name: "runtime-configmap"
---
What am I doing wrong that I don't get data?

Answer 1

The replacement of the variable within the string does not work:
{{ .Files.Get "files/{{ .Values.configmapName}}-config.json" | indent 2}}
But you can gerenate a string using the printf function like this:
{{ .Files.Get (printf "files/%s-config.json" .Values.configmapName) | indent 2 }}

Answer 2

Apart from the syntax problem pointed by #adebasi, you still need to set this code inside a key to get a valid configmap yaml:
apiVersion: v1
kind: ConfigMap
metadata:
name: "{{ .Values.configmapName}}-configmap"
labels:
app: "{{ .Values.configmapName}}"
data:
my-file: |
{{ .Files.Get (printf "files/%s-config.json" .Values.configmapName) | indent 4}}
Or you can use the handy configmap helper:
apiVersion: v1
kind: ConfigMap
metadata:
name: "{{ .Values.configmapName}}-configmap"
labels:
app: "{{ .Values.configmapName}}"
data:
{{ (.Files.Glob "files/*").AsConfig | indent 2 }}