user-data

#cloud-config

bootcmd:
 - echo HELLO FROM USER DATA SCRIPT | tee /msg > /dev/kmsg
 - apt-get update 
 - apt-get install -y awscli jq

 # fyi. this script works but hasn't been tested in user data yet.. so yaml/cloud-init issues beware
 - |-
    set -eu
    
    export AWS_REGION="$(curl 169.254.169.254/latest/meta-data/placement/region)"
    export AWS_DEFAULT_REGION="$(curl 169.254.169.254/latest/meta-data/placement/region)"

    # Format of the results:
    #   operation per line
    #   disassociate:<assoicationId>:<tmpRouteTable>  -- disassociate assoicationId and delete tmpRouteTable
    #   <origTableId>:<assoicationId>:<tmpRouteTable>  -- replace assoicationId with origTableId and delete tmpRouteTable
    results="$(aws ec2 describe-route-tables --filter "Name=tag-key,Values=OrigRouteTableId" |jq -r '.RouteTables|.[].Tags|.[]| select(.Key == "OrigRouteTableId")|.Value'|uniq)"

    echo "$results" | while read line; do
      origTableId="$(echo "$line"|cut -d: -f 1)";
      assoicationId="$(echo "$line"|cut -d: -f 2)";
      tmpRouteTable="$(echo "$line"|cut -d: -f 3)";

      echo "origTableId: ${origTableId}, assoicationId: ${assoicationId}, tmpRouteTable: ${tmpRouteTable}" 

      if echo "$origTableId"| grep "disassociate"; then
        aws ec2 disassociate-route-table --association-id "$assoicationId" 
      else
        aws ec2 replace-route-table-association --association-id "$assoicationId" --route-table-id "$origTableId"
      fi

      aws ec2 delete-route-table --route-table-id "$tmpRouteTable"
    done
 - cloud-init clean && reboot