message: Remove unused SOURCE argument
  This also fixes an issue where the command to roll back to the original
  service was incorrect if you specified a source read-only endpoint.
diff: # What this script is for
  # =======================
  # This script will migrate a database user, access, database and contents from
  -# a source cluster to a destination cluster.
  +# an existing cluster to a destination cluster.
  #
  # At the moment, this is geared towards the Ansible Service Broker, but likely
  # can be modified in the future to work with the DBaaS operator.
  # ============
  # * You are logged into OpenShift CLI and have access to the NAMESPACE you want
  # to migrate.
  -# * You have a `.my.cnf` file for the source and desintation database clusters.
  -# * If your database clusters are not directly accessible, then you have
  -# created SSH tunnels to expose them on a local port.
  +# * You have a `.my.cnf` file for the desintation database cluster.
  +# * If your destination database cluster is not directly accessible, then you
  +# have created SSH tunnels to expose them on a local port.
  #
  # How to get your existing ASB root credentials
  # =============================================
  # Example commands
  # ================
  # ./helpers/shared-to-shared-migrate.sh \
  -# --source shared-cluster.cluster-banana.ap-southeast-2.rds.amazonaws.com \
  # --destination shared-cluster.cluster-apple.ap-southeast-2.rds.amazonaws.com \
  # --replica shared-cluster.cluster-r0-apple.ap-southeast-2.rds.amazonaws.com \
  # --namespace NAMESPACE \
  set -euo pipefail
  # Initialize our own variables:
  -SOURCE_CLUSTER=""
  DESTINATION_CLUSTER=""
  REPLICA_CLUSTER=""
  NAMESPACE=""
  @@ -95,11 +93,6 @@ while [[ $# -gt 0 ]] ; do
  key="$1"
  case $key in
  - -s|--source)
  - SOURCE_CLUSTER="$2"
  - shift # past argument
  - shift # past value
  - ;;
  -d|--destination)
  DESTINATION_CLUSTER="$2"
  shift # past argument
  @@ -123,7 +116,6 @@ while [[ $# -gt 0 ]] ; do
  done
  shw_grey "================================================"
  -shw_grey " SOURCE_CLUSTER=$SOURCE_CLUSTER"
  shw_grey " DESTINATION_CLUSTER=$DESTINATION_CLUSTER"
  shw_grey " REPLICA_CLUSTER=$REPLICA_CLUSTER"
  shw_grey " NAMESPACE=$NAMESPACE"
  @@ -206,7 +198,7 @@ shw_norm "================================================"
  # Alter the network service(s).
  shw_info "> Altering the Network Service $DB_NETWORK_SERVICE to point at $DESTINATION_CLUSTER"
  shw_info "================================================"
  -oc -n "$NAMESPACE" get "svc/$DB_NETWORK_SERVICE" -o json --export > "/tmp/$NAMESPACE-svc.json"
  +ORIGINAL_DB_HOST=$(oc -n "$NAMESPACE" get "svc/$DB_NETWORK_SERVICE" -o json --export | tee "/tmp/$NAMESPACE-svc.json" | jq -er '.spec.externalName')
  if [ "$DRY_RUN" ] ; then
  echo "**DRY RUN**"
  else
  @@ -249,7 +241,7 @@ shw_grey "================================================"
  shw_grey ""
  shw_grey "In order to rollback this change, edit the Network Service(s) like so:"
  shw_grey ""
  -shw_grey "oc -n ${NAMESPACE} patch svc/${DB_NETWORK_SERVICE} -p \"{\\\"spec\\\":{\\\"externalName': \\\"${SOURCE_CLUSTER}\\\"}}\""
  +shw_grey "oc -n ${NAMESPACE} patch svc/${DB_NETWORK_SERVICE} -p \"{\\\"spec\\\":{\\\"externalName': \\\"${ORIGINAL_DB_HOST}\\\"}}\""
  if [ "$DB_READREPLICA_HOSTS" ]; then
  shw_grey "oc -n ${NAMESPACE} patch svc/${DB_READREPLICA_HOSTS} -p \"{\\\"spec\\\":{\\\"externalName': \\\"${ORIGINAL_DB_READREPLICA_HOSTS}\\\"}}\""
  fi
  