buildah.yaml

---
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: buildah-source-pvc
spec:
  accessModes:
    - ReadWriteOnce
  resources:
    requests:
      storage: 500Mi
---
apiVersion: tekton.dev/v1beta1
kind: Pipeline
metadata:
  name: buildah-test-pipeline
spec:
  workspaces:
  - name: shared-workspace
  tasks:
  - name: fetch-repository
    taskRef:
      name: git-clone
    workspaces:
    - name: output
      workspace: shared-workspace
    params:
    - name: url
      value: https://github.com/kelseyhightower/nocode
    - name: subdirectory
      value: ""
    - name: deleteExisting
      value: "true"
  - name: buildah
    taskRef:
      name: buildah
    runAfter:
    - fetch-repository
    workspaces:
    - name: source
      workspace: shared-workspace
    params:
    - name: IMAGE
      value: image-registry.openshift-image-registry.svc:5000/pthangad-v1beta1/nocode:latest
    - name: TLSVERIFY
      value: "false"
---
apiVersion: tekton.dev/v1beta1
kind: PipelineRun
metadata:
  name: buildah-test-pipeline-run
spec:
  pipelineRef:
    name: buildah-test-pipeline
  workspaces:
  - name: shared-workspace
    persistentvolumeclaim:
      claimName: buildah-source-pvc

Perform below steps to try out work spaces

1. oc new-project pthangad-v1beta1
2. oc apply -f https://raw.githubusercontent.com/tektoncd/catalog/v1beta1/git/git-clone.yaml
3. oc apply -f https://raw.githubusercontent.com/tektoncd/catalog/v1beta1/buildah/buildah.yaml
4. oc apply -f https://gist.githubusercontent.com/praveen4g0/b2f08e66396e73609845ed6b10afb4f4/raw/2099fd0b24986b8d1a9e09b4f977cda08a92d31a/buildah.yaml

use tkn cli to run pipeline
5. tkn pipeline start buildah-test-pipeline -w=name=shared-workspace,claimName=buildah-source-pvc