linshenkx/prompt-optimizer · error · Error

Invalid favorite share payload

Error message

Invalid favorite share payload

What it means

Thrown by parseSharePayload when a parsed JSON object does not match the FavoriteSharePayload schema: it must be a record with schemaVersion equal to FAVORITE_SHARE_SCHEMA_VERSION, format equal to 'favorite-share', and a string packageBase64 field. This is a strict schema guard against tampered, outdated, or unrelated JSON.

Source

Thrown at packages/ui/src/utils/favorite-share-export.ts:1440

  const textBytes = data.slice(offset)
  try {
    return compressionFlag === 1
      ? strFromU8(unzlibSync(textBytes))
      : strFromU8(textBytes)
  } catch {
    return null
  }
}

const parseSharePayload = (value: string): FavoriteSharePayload => {
  const parsed = JSON.parse(value) as unknown
  if (
    !isRecord(parsed) ||
    parsed.schemaVersion !== FAVORITE_SHARE_SCHEMA_VERSION ||
    parsed.format !== 'favorite-share' ||
    typeof parsed.packageBase64 !== 'string'
  ) {
    throw new Error('Invalid favorite share payload')
  }
  return parsed as FavoriteSharePayload
}

export const readFavoriteSharePackage = (
  input: ArrayBuffer | Uint8Array | string,
): Uint8Array => {
  if (typeof input === 'string') {
    const parser = new DOMParser()
    const document = parser.parseFromString(input, 'text/html')
    const script = document.getElementById(FAVORITE_SHARE_HTML_SCRIPT_ID)
    if (!script?.textContent) {
      throw new Error('This HTML file does not contain Prompt Optimizer favorite share data')
    }
    return base64ToBytes(parseSharePayload(script.textContent).packageBase64)
  }

  const bytes = input instanceof Uint8Array ? input : new Uint8Array(input)

View on GitHub (pinned to 3e677b1d9f)

Solutions

1. Confirm FAVORITE_SHARE_SCHEMA_VERSION matches the version written at export time; if not, migrate or re-export
2. Inspect the embedded JSON (log the tEXt chunk content) to see which field fails: schemaVersion, format, or packageBase64
3. Validate the payload with parseSharePayload in a try/catch and show a friendly 'unsupported share file version' message
4. Re-export the share from a current app version instead of editing payloads by hand

Example fix

// before
const pkg = readFavoriteSharePackage(file) // throws on version mismatch

// after
let pkg
try {
  pkg = readFavoriteSharePackage(file)
} catch (e) {
  if (e instanceof Error && e.message === 'Invalid favorite share payload') {
    throw new UserError('This share file is unsupported or was exported by an incompatible version.')
  }
  throw e
}

const raw = JSON.parse(text)
const ok =
  raw && typeof raw === 'object' &&
  raw.schemaVersion === FAVORITE_SHARE_SCHEMA_VERSION &&
  raw.format === 'favorite-share' &&
  typeof raw.packageBase64 === 'string'
if (!ok) throw new UserError('Unsupported share file version')

const isFavoriteSharePayload = (v: unknown): v is FavoriteSharePayload =>
  typeof v === 'object' && v !== null &&
  (v as any).schemaVersion === FAVORITE_SHARE_SCHEMA_VERSION &&
  (v as any).format === 'favorite-share' &&
  typeof (v as any).packageBase64 === 'string'

try { readFavoriteSharePackage(input) } catch (e) { if (e.message === 'Invalid favorite share payload') showVersionMismatchUI(); else throw e }

When it happens

Trigger: Importing a share payload whose JSON has a different schemaVersion (old export vs new importer), a missing or misspelled format field, packageBase64 that is null/number/undefined, or JSON that is valid but not a share object at all (e.g. arbitrary JSON embedded in a tEXt chunk with the same keyword).

Common situations: Version skew: shares exported by an older app version are imported by a newer one (or vice versa); users hand-editing the embedded JSON; a PNG tEXt keyword collision where unrelated software wrote the same keyword; corrupted base64 that decoded to partial JSON.

Understand the failure class

Background: Schema validation failed / invalid input schema: payload rejected because its shape doesn't match the expected schema — this error's family across 28 libraries.

Related errors

• Unsupported Garden response schema
• Invalid import data format
• variables[${index}] is missing a valid "position" object.
• variables[${index}].position is missing a valid "originalTex
• variables[${index}] is missing a valid "reason" field.

AI-assisted analysis of linshenkx/prompt-optimizer@3e677b1d9f (2026-08-27). Data as JSON: /api/errors/fc83740cd0af85f2. Report an issue: GitHub.