Update deprecated kubernetes api version that's stored in a helm release that's stored in a secret

upgrade_helm_manifest_api_version.sh

#!/bin/bash

# Strict mode
set -euo pipefail

if [ $# -ne 3 ]; then
    echo "Usage: $0 <helm_release_name> <old_api_version> <new_api_version>"
    exit 1
fi

HELM_RELEASE_NAME=$1
OLD_API_VERSION=$2
NEW_API_VERSION=$3

SECRET_NAME=$(kubectl get secret -l name=${HELM_RELEASE_NAME},owner=helm,status=deployed --no-headers -o name | sort --version-sort | tail -n 1)

if [[ -z "${SECRET_NAME}" ]]; then
    echo "No deployed release found for helm release ${HELM_RELEASE_NAME}"
    exit 1
fi

BACKUP_FILE=${HELM_RELEASE_NAME}_secret_backup_$(date +%y%m%d_%H%M%S).json

# Backup the secret
kubectl get $SECRET_NAME -o json > ${BACKUP_FILE}

RELASE_VERSION=$(jq -r .metadata.labels.version ${BACKUP_FILE})

BACKUP_FILE_WITH_VERSION=${HELM_RELEASE_NAME}_secret_backup_release_${RELASE_VERSION}_$(date +%y%m%d_%H%M%S).json

cp ${BACKUP_FILE} ${BACKUP_FILE_WITH_VERSION}

echo "Using release version $RELASE_VERSION"

jq '.data.release' -r ${BACKUP_FILE} \
    | base64 -d \
    | base64 -d \
    | gunzip - \
    | jq . > ${HELM_RELEASE_NAME}_manifest.json

# Update the apiVersion
sed -e "s|${OLD_API_VERSION}|${NEW_API_VERSION}|g" ${HELM_RELEASE_NAME}_manifest.json > ${HELM_RELEASE_NAME}_manifest_updated.json

diff <(cat ${HELM_RELEASE_NAME}_manifest.json | jq .manifest -r) <( cat ${HELM_RELEASE_NAME}_manifest_updated.json | jq .manifest -r) || true

# Update the existing secret stored in ${HELM_RELEASE_NAME}_manifest_updated.json
NEW_RELEASE=$(cat ${HELM_RELEASE_NAME}_manifest_updated.json \
    | gzip -c \
    | base64 -w 0 \
    | base64 -w 0)

# Update the secret
echo "Updating the secret ${SECRET_NAME} with the new release"
kubectl patch $SECRET_NAME -p '{"data":{"release":"'${NEW_RELEASE}'"}}'