Blue Green Deployment with Cloud Foundry

cf_blue_green_deploy.sh

#!/bin/bash

set -euo pipefail
cf login  -a "$CF_API" -u "$CF_USER" -p "$CF_PASSWORD" -o "$CF_ORG" -s "$CF_SPACE" 
APP_NAME_TMP="${APP_NAME}-venerable"

# Deploy a new application if doesn't exist and do blue-green otherwise
if [[ $(cf app "$APP_NAME" --guid 2>&1 1>/dev/null) == "App $APP_NAME not found" ]]; then
  cf push
else
  cf rename "$APP_NAME" "$APP_NAME_TMP"
  if cf push; then
    cf delete -f "$APP_NAME_TMP"
  else
    cf delete -f "$APP_NAME" 
    cf rename "$APP_NAME_TMP" "$APP_NAME" 
  fi
fi