set-up-app

#!/bin/sh
set -e

APP="grapnel"
FN="grapnel"
SUBNET=""
REMOTE_HOST=""
REMOTE_USER="opc"

while getopts "a:f:s:h:u:" opt; do
  case ${opt} in
    a) APP="$OPTARG" ;;
    f) FN="$OPTARG" ;;
    s) SUBNET="$OPTARG" ;;
    h) REMOTE_HOST="$OPTARG" ;;
    u) REMOTE_USER="$OPTARG" ;;
  esac
done
shift $((OPTIND - 1))

die() {
  echo "$@" 1>&2
  exit 1
}

[[ -z "$REMOTE_HOST" ]] && die "Please specify the target host address with -h REMOTE_HOST"


# Create the host keys
[[ -f h_to_f ]] || ssh-keygen -t rsa -f h_to_f -N "" -C "host-to-function"
[[ -f f_to_h ]] || ssh-keygen -t rsa -f f_to_h -N "" -C "function-to-host"
echo "Host keys created. DO NOT USE THESE ANYWHERE ELSE"

echo "Add the following 'authorized_keys' entry to the user $REMOTE_USER on the launch host $REMOTE_HOST"
cat f_to_h.pub


# Annotation for OCI serverless
fn create app $APP \
  --annotation oracle.com/oci/subnetIds='["'"$SUBNET"'"]'

[[ -f func.yaml ]] || fn init --name "$FN" --runtime docker
fn --verbose deploy --app "$APP"


# Configure the function.
if [[ "$(uname)" != Darwin ]]; then
  base64() {
    command base64 -w 0 "$@"
  }
fi
  
fn config function "$APP" "$FN" remote_ip "$REMOTE_HOST"
fn config function "$APP" "$FN" remote_user "$REMOTE_USER"
fn config function "$APP" "$FN" local_pub "$(base64 h_to_f.pub)"
fn config function "$APP" "$FN" remote_priv "$(base64 f_to_h)" | sed -e 's/ with .*$/ with *REDACTED*/'


cat <<-EOF
	Function configured. WARNING: its configuration contains a private key without passphrase!

	Complete the configuration as follows:
	1. On the target host $REMOTE_HOST, add the ~/.ssh/authorized_keys entry to user $REMOTE_USER:
	$(cat f_to_h.pub)

	2. Copy the private key associated with the function to $REMOTE_HOST.
	   This is in the file h_to_f

	2. Use ./keep-function-running to keep the shell open and active.

	3. On $REMOTE_HOST, wait for a listening socket on localhost:9999 to appear, then:
	ssh -v -p 9999 -i h_to_f -o StrictHostKeyChecking=no -o UserKnownHostsFile=/dev/null root@localhost
	EOF