Function maskEmailForLogging

apps/api/src/lib/email/email.utils.ts:49–71

(email: string)

 *   ""                   -> "***"
 */
export const maskEmailForLogging = (email: string): string => {
  if (email === "") {
    return "***";
  }

  const atIndex = email.indexOf("@");

  if (atIndex === -1) {
    return "***";
  }

  const localPart = email.slice(0, atIndex);
  const domain = email.slice(atIndex + 1);

  if (localPart.length <= 2) {
    return `***@${domain}`;
  }

  const first = localPart[0] ?? "";
  const last = localPart[localPart.length - 1] ?? "";

  return `${first}***${last}@${domain}`;
};

/**
 * Boundary validator for outbound email payloads. Throws an `ApiError`