Files Attachments not sync

[navigator8]

I added a pdf on my iphone and tried to open the same note and file on ipad. The file is not being found?

[colebemis]

I've noticed this too. Will investigate.

[navigator8]

@colebemis any updates on pdf files. I am still experiencing issues with synchronization of files.

[srikat]

Came to report the same.

I dragged a PDF in. Pressed Save. I can view it in the app but it is not present in the Git repo under uploads.

[colebemis]

@srikat How big is the file you uploaded? I think this might be a bug where Lumen is silently failing when attachments are too big

[srikat]

@srikat How big is the file you uploaded? I think this might be a bug where Lumen is silently failing when attachments are too big

4.8 MB

Screencast: https://sri.smmall.cloud/MTc2OTc0MDMyMzQwMg

[colebemis]

@srikat Screencast is super helpful. Thank you! As a sanity check, can you try uploading a small PDF and see if that works (i.e. gets successfully uploaded to GitHub)

[srikat]

@colebemis Tried a 72 KB file and it works.

Per https://docs.github.com/en/repositories/working-with-files/managing-large-files/about-large-files-on-github, looks like the limit for file sizes is 50 MB. I tried the 4.8MB file again and it still failed to get uploaded to my Git repo.

[colebemis]

I asked Claude to investigate. Here's what it found:

---

Investigation Findings

The file sync issue is caused by silent upload failures due to size limits in two different code paths:

Path 1: With Git LFS configured

Files are uploaded through a Vercel serverless function (api/git-lfs-file.ts) which has a 4.5MB request body limit (Vercel Hobby plan default). Since files are base64 encoded before upload (+33% overhead), the effective limit is ~3.4MB.

The upload flow:

Browser → Vercel function (4.5MB limit) → GitHub LFS

Path 2: Without Git LFS

Files go directly through isomorphic-git with these limits:

• GitHub: 100MB per file (hard limit for non-LFS)
• IndexedDB: ~50-500MB total (varies by device, iOS is stricter)
• Push can timeout on slow mobile networks

Why files appear locally but don't sync

In src/hooks/attach-file.ts, upload errors are only logged to console:

writeFile(...)
  .catch((error) => {
    console.error(error) // Silent failure!
  })

The file is cached locally in IndexedDB and markdown is inserted, so it looks successful. But the actual upload to GitHub fails silently.

---

Recommended Fixes

1. Direct upload to GitHub LFS (bypasses Vercel limit)

Split the upload into two steps:

1. Small request to Vercel to get upload URL from GitHub's LFS batch API
2. Upload binary directly from browser to GitHub LFS

Browser → Vercel (get URL only) → Browser → GitHub LFS directly

This removes the Vercel body limit entirely. Only limit becomes GitHub's ~2GB per file.

2. Add user-facing error handling

Show toast/notification when upload fails instead of silent console.error.

3. Add upfront file size validation

Check file size before upload and warn user:

• No LFS configured: warn if > 100MB
• With LFS (current): warn if > ~3MB
• With LFS (after fix): no practical limit

[srikat]

Hope you can implement the LFS fix.