selectel-ddns

#!/bin/bash

# Get the directory path of the script
SCRIPT_DIR=$(dirname "$(realpath "$0")")

# File to store the current IP address
IP_FILE="$SCRIPT_DIR/ip.txt"

function check_requirements {
  for PROGRAM in jq curl; do
    if ! [ -x "$(command -v $PROGRAM)" ]; then
      echo "Error: $PROGRAM is not installed. Please install $PROGRAM before running this script." >&2
      exit 1
    fi
  done

  # Check if the .env file exists
  if [ ! -f "$SCRIPT_DIR/.env" ]; then
    echo 'Error: .env file not found. Please create a .env file in the same directory as this script.' >&2
    exit 1
  fi

  source "$SCRIPT_DIR/.env"

  # Check if the token is set
  if [ -z "$TOKEN" ]; then
    echo 'Error: Selectel API token not found in .env file. Please add the token to the .env file.' >&2
    exit 1
  fi

  # Check if the domains list is set
  if [ -z "$DOMAINS" ]; then
    echo 'Error: Domain list not found in .env file. Please add the domain list to the .env file.' >&2
    exit 1
  fi

  # Check if the IP file exists
  if [ ! -f "$IP_FILE" ]; then
    echo "" >"$IP_FILE"
  fi
}

function get_domain_id {
  local domain="${1}"

  echo "Getting domain ID for ${domain}"
  local response=$(curl -sS -H "X-Token: ${TOKEN}" "${API_ENDPOINT}${domain}")

  if [[ $(echo $response | jq -r ".error") != "null" ]]; then
    error_message=$(echo $response | jq -r ".error")
    echo "Error obtaining domain id: $error_message" >&2
    exit 1
  fi

  local record_id=$(echo $response | jq -r ".id")
  echo $record_id
}

function update_record {
  local domain_id="${1}"
  local record_id=$(echo "${2}")

  echo "Updating record with ID: ${record_id}"

  local json='{"type": "A", "content": "'${CURRENT_IP}'"}'
  local url="${API_ENDPOINT}${domain_id}/records/${record_id}"

  local response=$(curl -sS -X PUT -H "X-token: $TOKEN" -H "Content-Type: application/json" -d "${json}" "${url}")

  if [[ $(echo "$response" | jq -r ".error") == "null" ]]; then
    echo "Record updated" >&2
    return 0
  else
    error_message=$(echo $response | jq -r ".error")
    echo "Error: $error_message" >&2
    return 1
  fi
}

function update_domain_records {
  get_domain_id $MAIN_DOMAIN
  local main_domain_id=$?
  local url="${API_ENDPOINT}${MAIN_DOMAIN}/records/"

  declare -a domain_names=($DOMAINS)
  local list=$(IFS=,; echo "${domain_names[*]}")

  local response=$(curl -sS -H "X-Token: ${TOKEN}" -H "Content-Type: application/json" "${url}")
  local d=$(echo $response | jq -r --arg list $list '.[] | select(.name as $a | $list | index($a)) | select(.type=="A") | .id')

  for resource_id in $d; do
    update_record ${main_domain_id} ${resource_id}
  done
}

check_requirements

EXISTING_IP=$(cat "$IP_FILE")
CURRENT_IP=$(curl -sS https://checkip.amazonaws.com/)
echo "Current IP: ${CURRENT_IP}"

if [ "${EXISTING_IP}" == "${CURRENT_IP}" ]; then
  echo "The IP is actual."
  exit 0
fi

update_domain_records

echo "${CURRENT_IP}" >"${IP_FILE}"