How to upload a file to kubernetes cluster for my Apps to access it?

Question

Lets say we have an application which accesses a file. This App is a jar which is packaged into an image and pushed to Registry for the Kubernetes to run it. But when we create the Pod, we need to configure a volume also in it. When we specify a volume we give a path, how do we place the file in that volume from lets say our virtual machine?

Please help me in understanding this with an explanation. Also should we create a storage so that its accessible from kubernetes cluster? please explain relevent topic as well to understand this.

Note: we are using azure cli

Answer 1

I think the best approach would be to create a ConfigMap with the data you want to use from your application. Then you just need to mount the ConfigMap as a volume in the Pod's ( explained here ) that need the data.

You can easily create a ConfigMap from a file like

kubectl create configmap your-configmap-name --from-file=/some/path/to/file

And then mount it in your Pod

apiVersion: v1
kind: Pod
metadata:
  name: dapi-test-pod
spec:
  containers:
    - name: test-container
      image: k8s.gcr.io/busybox
      command: [ "/bin/sh", "-c", "ls /etc/config/" ]
      volumeMounts:
      - name: config-volume
        mountPath: /etc/config
  volumes:
    - name: config-volume
      configMap:
        # Provide the name of the ConfigMap containing the files you want
        # to add to the container
        name: special-config