create-ign.sh

#!/usr/bin/env bash

if [ $# -eq 0 ] ; then
  echo "Usage: $0 HOSTNAME bootstrap_ignition_config_url";
  exit 1;
fi

HOSTNAME=${1:-bootstrap.ocp4-upi.bohne.io}
IGN_URL=${2}

json=$(cat <<EOF
{
  "ignition": {
    "config": {
      "append": [
        {
          "source": "$IGN_URL",
          "verification": {}
        }
      ]
    },
    "timeouts": {},
    "version": "2.1.0"
  },
  "networkd": {},
  "passwd": {},
  "systemd": {},
  "storage": {
    "files": [
    {
        "contents": {
             "source":"data:text/plain;charset=utf-8;base64,$(echo $HOSTNAME | base64 -w0 )"
        },
        "filesystem": "root",
        "path": "/etc/hostname",
        "mode": 420,
        "user": {
            "name": "root"
        }
    }
    ]
  }
}
EOF
)

echo $json