add update script

update.sh

@@ -0,0 +1,37 @@
+#!/usr/bin/env bash
+
+set -e
+
+echo "Updating OneUptime. This will cause a few minutes of downtime. If you would like to avoid downtime, please consider installing this on a Kubernetes cluster."
+read -r -p "Do you want to update OneUptime? [y/N] " response
+if [[ "$response" =~ ^([yY][eE][sS]|[yY])+$ ]]
+then
+    echo "OK!"
+else
+    exit
+fi
+
+cd oneuptime
+git pull
+cd ../
+
+rm -f docker-compose.yml
+cp oneuptime/docker-compose.yml docker-compose.yml.tmpl
+envsubst < docker-compose.yml.tmpl > docker-compose.yml
+rm docker-compose.yml.tmpl
+
+docker-compose pull
+
+echo "Stopping the stack!"
+docker-compose stop
+
+echo "Checking if async migrations are up to date"
+sudo -E docker-compose run init
+
+
+
+echo "OK, Restarting the stack!"
+sudo -E docker-compose up -d
+
+
+echo "OneUptime upgraded successfully!"