使用方法
- 复制安装命令，在自己的智能体环境安装前先检查源码包。
- 从原始文档核对所需工具、凭据和支持的宿主。
- 说明输入材料与期望交付物，并对照来源检查输出。
npx skills add https://github.com/nexu-io/open-design --skill export-download-debugging开始前需了解
- 安装不包含模型订阅、API 额度或访问文件的权限。
- 仓库星数和安装量反映活跃情况，不等于独立质量或安全测试。
按源仓库内容呈现，保留标题、案例、代码、表格、链接以及原文引用的演示图片。
Export Download Debugging
Use this when an export or download appears to run but produces an empty, missing, or unusable file. It is tuned for browser previews, iframe capture, and Electron shells.
Core rule
Separate capture from save. Prove the export payload has non-zero bytes before debugging the destination path. A 0 KB file often means the native picker or host created the target file, then the write failed or was blocked.
Evidence
- Record the payload type, MIME type, byte length, object URL or data URL path,
and thrown error name/message.
- Check browser console output and app logs around
showSaveFilePicker,
createWritable, <a download>, URL.createObjectURL, and URL revocation.
- In Electron, inspect the
will-downloadpath: filename, MIME, file extension,
save dialog filters, cancellation, and final file size.
- Confirm the actual downloaded file size on disk and whether it opens in a
normal image viewer.
Fix order
- Prepare and validate the export payload first; disable Save until bytes are
available.
- Prefer the simplest stable save channel for the host. If
showSaveFilePicker().createWritable() fails, is sandboxed, or creates empty files, route to <a download> or Electron's download manager instead.
- Avoid opening a native picker before the payload is ready. This prevents the
host from creating an empty destination file on later write failure.
- For PNG fallback, prefer a verified non-empty data URL when blob URLs,
revocation timing, CSP, or iframe sandboxing are suspicious.
- In Electron, add explicit Save As filters for exported image extensions
(.png, .jpg, .jpeg, .webp) so users can choose a real image target.
- Keep the UI restrained: format selection, filename/path hint, clear pending
and error states, and one primary save action.
Validation
- Add or update tests for non-empty payload preparation, fallback save behavior,
file extension/MIME mapping, and UI disabled/error states.
- Run focused export tests, then
pnpm --filter @open-design/web typecheck. - If Electron download handling changed, also run
pnpm --filter @open-design/desktop typecheck.
- Before landing, run
pnpm guard, inspect the staged diff for unrelated files,
generated artifacts, and accidental secrets, then use the repository's PR quality-gate workflow if the fix is being prepared for review.
