linshenkx/prompt-optimizer · error · Error

app backup package is missing app-data.json

Error message

app backup package is missing app-data.json

What it means

Thrown by readDataManagerResourcePackage in packages/ui/src/utils/data-manager-resource-package.ts when the zip contains manifest.json but no entry at APP_DATA_JSON_PATH ('app-data.json'). The app data payload is mandatory for restore, so the package is rejected. This check runs after the manifest.json presence check, so the archive is already known to be a plausible backup.

Source

Thrown at packages/ui/src/utils/data-manager-resource-package.ts:293

export const readDataManagerResourcePackage = (
  input: ArrayBuffer | Uint8Array,
): {
  manifest: DataManagerResourcePackageManifest
  appDataJson: string
  favoritesJson: string
  files: Record<string, Uint8Array>
} => {
  const bytes = input instanceof Uint8Array ? input : new Uint8Array(input)
  const files = unzipSync(bytes)
  const manifestBytes = files['manifest.json']
  const appDataBytes = files[APP_DATA_JSON_PATH]
  const favoritesBytes = files[FAVORITES_JSON_PATH]

  if (!manifestBytes) {
    throw new Error('app backup package is missing manifest.json')
  }
  if (!appDataBytes) {
    throw new Error('app backup package is missing app-data.json')
  }
  if (!favoritesBytes) {
    throw new Error('app backup package is missing favorites.json')
  }

  return {
    manifest: parseManifest(strFromU8(manifestBytes)),
    appDataJson: strFromU8(appDataBytes),
    favoritesJson: strFromU8(favoritesBytes),
    files,
  }
}

const getImportStorageService = (
  store: DataManagerImageStoreKey,
  options: ImportDataManagerResourcePackageOptions,
): Pick<IImageStorageService, 'getImage' | 'saveImage'> | null | undefined =>
  store === 'favoriteImages'

View on GitHub (pinned to 3e677b1d9f)

Solutions

  1. Verify the zip contains an 'app-data.json' entry at the root alongside manifest.json
  2. Re-export the backup from the source app rather than repairing a partial package
  3. If the export was interrupted, discard the file and retry the export to get a complete archive
  4. Pre-validate entries before calling readDataManagerResourcePackage and surface a file-picker error to the user

Example fix

// before
const pkg = readDataManagerResourcePackage(bytes) // throws: missing app-data.json

// after
const names = Object.keys(unzipSync(bytes))
for (const required of ['manifest.json', 'app-data.json', 'favorites.json']) {
  if (!names.includes(required)) throw new Error(`Backup incomplete: no ${required}`)
}
const pkg = readDataManagerResourcePackage(bytes)
Defensive patterns

Strategy: validation

Validate before calling

import { unzipSync } from 'fflate'

const REQUIRED = ['manifest.json', 'app-data.json', 'favorites.json'] as const

const hasAllEntries = (bytes: Uint8Array): boolean => {
  try {
    const entries = Object.keys(unzipSync(bytes))
    return REQUIRED.every((name) => entries.includes(name))
  } catch {
    return false
  }
}

Try / catch

try {
  const pkg = readDataManagerResourcePackage(bytes)
} catch (e) {
  if (e instanceof Error && e.message.includes('missing app-data.json')) {
    // treat as incomplete/corrupt export; ask user to re-export
    return
  }
  throw e
}

Prevention

When it happens

Trigger: A zip with manifest.json present but app-data.json absent: partially generated packages where the app-data write failed, an archive repacked without the payload file, a renamed or moved app-data.json entry, or a manifest-only zip used as a template.

Common situations: Interrupted export (disk full, tab closed) producing a partial zip; manual repackaging that dropped the payload; upload pipeline that filters 'unnecessary' JSON files; filename casing differences introduced by zip tools.

Related errors

AI-assisted analysis of linshenkx/prompt-optimizer@3e677b1d9f (2026-08-27). Data as JSON: /api/errors/eb9b6ac44752188e. Report an issue: GitHub.