Function resolveFileType

apps/sim/lib/uploads/utils/file-utils.ts:322–333

(
  file: { type: string; name: string },
  options?: { preserveOctetStream?: boolean }
)

 * browser-supplied content-type must match the presigned handshake exactly.
 */
export function resolveFileType(
  file: { type: string; name: string },
  options?: { preserveOctetStream?: boolean }
): string {
  const browserType = file.type?.trim()
  if (browserType) {
    if (options?.preserveOctetStream || browserType !== 'application/octet-stream') {
      return browserType
    }
  }
  return getMimeTypeFromExtension(getFileExtension(file.name))
}

/**
 * Upload `Content-Type` for direct PUT — preserves the browser's reported type