#################### Retrieve backup ARN id ####################
aws backup list-recovery-points-by-backup-vault --backup-vault-name $VAULT_NAME
# NOTE: Record the RecoveryPointArn that you wish to recover from
# e.g. arn:aws:backup:ap-southeast-1:027763730008:recovery-point:0a82d94c-3d56-481d-98e3-b810d3df363b

# To view the recovery point restore metadata
aws backup get-recovery-point-restore-metadata \
--backup-vault-name $VAULT_NAME \
--recovery-point-arn <RECOVERY_POINT_ARN>

#################### Restore from the backup ####################
# Prerequisites:
# 1) Generate an UUID, "uuidgen" (Mac) or "uuid -r" (Linux)
# 2) Create a metadata json file, properties details are mentioned in
# https://docs.aws.amazon.com/aws-backup/latest/devguide/restoring-efs.html#efs-restore-cli
# NOTE: If newFileSystem=true, file-system-id parameter will be ignored.
# 3) Substitute "CreationToken" value with the generated UUID.
# 4) If existing file system is encrypted, you may use the existing KMS key.
#
# Example metadata json:

# cat <<-EOF > /path/to/metadata_json_file
# {
#   "file-system-id": "fs-6a1dcba2",
#   "Encrypted": "true",
#   "KmsKeyId": "arn:aws:kms:ap-southeast-1:027763730008:key/4859a845-3ef2-464d-80d2-16c1b2c58ff4",
#   "PerformanceMode": "generalPurpose",
#   "CreationToken": "944713C9-C6BB-42A4-AF91-E7DB5761FDBD",
#   "newFileSystem": "true"
# }
# EOF

aws backup start-restore-job --recovery-point-arn <RECOVERY_POINT_ARN> --iam-role-arn "$BACKUP_ROLE_ARN" --metadata file:///path/to/metadata_json_file
watch aws backup list-restore-jobs --by-resource-type EFS

#################### Export new file system id ####################
# If you recover as new file system (newFileSystem=true), please use command `aws efs describe-file-systems` to find out the new file system id.
# After that export the new file system id env variable.
export NEW_EFS_FILE_SYSTEM_ID="fs-xxxxxxxxxxxxxxxxx";

#################### Create mount targets for new file system ####################
# Retrieve mount targets from existing file system and create the same to new file system.
for mountTarget in $(jq -c '.[]' <<< $(aws efs describe-mount-targets --file-system-id $EFS_FILE_SYSTEM_ID --query "MountTargets[?MountTargetId!=null]")); do
  zoneName=$(jq -r '.AvailabilityZoneName' <<< $mountTarget);
  mountTargetId=$(jq -r '.MountTargetId' <<< $mountTarget);
  subnetId=$(jq -r '.SubnetId' <<< $mountTarget);
  securityGroup=$(aws efs describe-mount-target-security-groups --mount-target-id $mountTargetId --query "SecurityGroups" --output text)
  echo "Creating mount target for file system id $NEW_EFS_FILE_SYSTEM_ID on zone $zoneName."
  aws efs create-mount-target \
    --file-system-id $NEW_EFS_FILE_SYSTEM_ID \
    --subnet-id $subnetId \
    --security-groups $securityGroup \
    --no-cli-pager
done

#################### Create root path access point to manage recovered data ####################
aws efs create-access-point \
--file-system-id $NEW_EFS_FILE_SYSTEM_ID \
--posix-user Uid=6000,Gid=6000 \
--root-directory 'Path="/",CreationInfo={OwnerUid=6000,OwnerGid=6000,Permissions="0755"}'

#################### Create access point for application access ####################
aws efs create-access-point \
--file-system-id $NEW_EFS_FILE_SYSTEM_ID \
--posix-user Uid=6000,Gid=6000 \
--root-directory 'Path="/uepe",CreationInfo={OwnerUid=6000,OwnerGid=6000,Permissions="0755"}'

aws efs describe-access-points

#################### Create a static persistent yaml ####################
# NOTE: Update volumeHandle to your file system id and access points accordingly.
# Example below are using two sets of PV and PVC that each of them corresponded to root path ("/") and application path ("/uepe").
# Use command `aws efs describe-access-points` to find out access point ids.

cat > efs_uepe_persistent.yaml << EOF
apiVersion: v1
kind: PersistentVolume
metadata:
  name: root-persistent
spec:
  capacity:
    storage: 5Gi
  volumeMode: Filesystem
  accessModes:
    - ReadWriteMany
  persistentVolumeReclaimPolicy: Retain
  storageClassName: aws-efs
  csi:
    driver: efs.csi.aws.com
    volumeHandle: fs-0faa7c3cdc681af41::fsap-08232180e9af33cab
---

apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: root-persistent
spec:
  volumeName: root-persistent
  storageClassName: aws-efs
  accessModes:
    - ReadWriteMany
  resources:
    requests:
      storage: 5Gi
---

apiVersion: v1
kind: PersistentVolume
metadata:
  name: platform-persistent
spec:
  capacity:
    storage: 5Gi
  volumeMode: Filesystem
  accessModes:
    - ReadWriteMany
  persistentVolumeReclaimPolicy: Retain
  storageClassName: aws-efs
  csi:
    driver: efs.csi.aws.com
    volumeHandle: fs-0faa7c3cdc681af41::fsap-06ee3201e68a278cd
---

apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: platform-persistent
spec:
  volumeName: platform-persistent
  storageClassName: aws-efs
  accessModes:
    - ReadWriteMany
  resources:
    requests:
      storage: 5Gi
EOF

#################### Kubectl apply persistence yaml ####################
kubectl apply -f efs_uepe_persistent.yaml

#################### Create temporary pods to manage volume ####################
cat <<EOF | kubectl apply -f -
apiVersion: v1
kind: Pod
metadata:
  name: root-pv-pod
spec:
  volumes:
    - name: root-persistent
      persistentVolumeClaim:
        claimName: root-persistent
  containers:
    - name: root-pv-container
      image: nginx
      volumeMounts:
        - mountPath: /root
          name: root-persistent
---

apiVersion: v1
kind: Pod
metadata:
  name: platform-pv-pod
spec:
  volumes:
    - name: platform-persistent
      persistentVolumeClaim:
        claimName: platform-persistent
  containers:
    - name: platform-pv-container
      image: nginx
      volumeMounts:
        - mountPath: /uepe
          name: platform-persistent
EOF

#################### Locate and move up the application backup directory (uepe) ####################
# Purpose of the below steps is to lift up restored folder to the root path, this is for allowing data to be accessible by the application access point.
kubectl exec -ti root-pv-pod -- ls -al /root/
kubectl exec -ti root-pv-pod -- ls -al /root/aws-backup-restore_2024-06-17T07-36-15-412650687Z
kubectl exec -ti root-pv-pod -- ls -al /root/aws-backup-restore_2024-06-17T07-36-15-412650687Z/uepe
kubectl exec -ti root-pv-pod -- cp -rf /root/aws-backup-restore_2024-06-17T07-36-15-412650687Z/uepe /root/
kubectl exec -ti root-pv-pod -- ls -al /root/uepe

#################### Verify restored data is visible by application mount point ####################
kubectl exec -ti platform-pv-pod -- ls -al /uepe

#################### Clean up unused pod, pv and pvc ####################
kubectl delete pod root-pv-pod
kubectl delete pod platform-pv-pod
kubectl delete pvc root-persistent
kubectl delete pv root-persistent

#################### Helm install PE with existing claim ####################
# The persistent volume has now been restored, you can install PE with the existing claim "platform-persistent".