@chainsafe/is-ip/src/is-ip.ts

Check if a string is an IP address

import { parseIP, parseIPv4, parseIPv6 } from "./parse.js";

/** Check if `input` is IPv4. */
export function isIPv4(input: string): boolean {
  return Boolean(parseIPv4(input));
}

/** Check if `input` is IPv6. */
export function isIPv6(input: string): boolean {
  return Boolean(parseIPv6(input));
}

/** Check if `input` is IPv4 or IPv6. */
export function isIP(input: string): boolean {
  return Boolean(parseIP(input));
}

/**
 * @returns `6` if `input` is IPv6, `4` if `input` is IPv4, or `undefined` if `input` is neither.
 */
export function ipVersion(input: string): 4 | 6 | undefined {
  if (isIPv4(input)) {
    return 4;
  } else if (isIPv6(input)) {
    return 6;
  } else {
    return undefined;
  }
}