Keep an import receipt beside the file fingerprint

A publishing tool can accept an import while its public output still needs checking. Keep a file fingerprint beside the acceptance receipt so the same file leads back to verification.

async function inspectImportFile(file, receipts) {
  if (!(file instanceof Blob) || !(receipts instanceof Map)) {
    throw new TypeError("Expected a Blob and a receipt Map");
  }
  if (file.size > 2 * 1024 * 1024) {
    throw new RangeError("This helper accepts files up to 2 MiB");
  }
  const bytes = await file.arrayBuffer();
  const digest = await crypto.subtle.digest("SHA-256", bytes);
  const key = Array.from(new Uint8Array(digest), byte =>
    byte.toString(16).padStart(2, "0")
  ).join("");
  return {
    key,
    next: receipts.get(key)?.status === "accepted"
      ? "verify-existing"
      : "reconcile-before-import"
  };
}

Record accepted only after an explicit success response. An absent or unknown receipt calls for reconciliation before another submission. This helper performs no upload and provides no server-side idempotency guarantee.

Three useful checks: identical bytes plus an accepted receipt return verify-existing; unknown receipts return reconcile-before-import; changed line endings require a new reconciliation. File fingerprints identify bytes. Continue deduplicating record destinations separately.

Web Crypto digest documentation explains the secure-context requirement and whole-input memory behavior. This helper limits files to 2 MiB. Six Node checks passed for the branches above, oversize files and invalid input; browser execution was not tested. Validate the import format separately.

I maintain the following example resource catalogs; the snippet is a standalone utility:

• AGProLabs screening-journal guide
• AliGurtuna calculator index
• Babamın Şiir Defteri reading-study index

AI-generated original code and writing; six Node behavior checks passed. Source links lead to projects I maintain.