How to get data from the configMap that mounted as volume in Golang

Question

I have a JSON file mounted by configMap:

apiVersion: v1
data:
  config.json: |
    {{- toPrettyJson $.Values.serviceConfig | nindent 4 }}

kind: ConfigMap
metadata:
  name: service-config
  namespace: {{ .Release.Namespace }} 

In deployment.yaml, it's:

    spec:
      ... ...
      volumes:
        - name: config-vol
          configMap:
            name: service-config
      containers:
        - name: {{ .Chart.Name }}
          ... ...
          volumeMounts:
            - mountPath: /src/config
              name: config-vol

My application needs to get that JSON file and use it, but how to retreive it by Go code. I searched it on the Internet but found nothing. If it's not able to retrieve, how can we use it? It's my first time touching the configMap, and I'm sorry if it's a dumb question. Thank you in advance!

Answer 1

Your deployment.yaml is pointing to the wrong configmap name first.

you can use something like

apiVersion: v1
kind: ConfigMap
metadata:
  name: command
data:
  command.json: |
    #!/bin/bash
    echo "running sh script on node..!"
---
          - name: command
            image: IMAGE
            imagePullPolicy: IfNotPresent
            volumeMounts:
            - name: commandfile
              mountPath: /test/command.json <---------------Path where you want to mount or add it and used by application from there as it is
              subPath: command.json
          restartPolicy: OnFailure
          volumes:
          - name: commandfile
            configMap:
              name: command       <------------------ configmap name should match