Google Drive Mirror

Automatic two-way sync between your Obsidian vault (whole vault or a single subfolder) and a Google Drive folder. You can edit, add, or delete files in Obsidian or directly in Google Drive — both sides are reconciled.

• ✅ Manual sync (ribbon icon + command) and automatic sync (upload shortly after a local change + interval polling for Drive)
• 📝 Google Workspace files, live inside Obsidian: open a Doc, Sheet, Slides or Drawing as a note and view — and edit on desktop — the real Google editor embedded right in the pane. View-only integration: the file is never downloaded or uploaded, so nothing can be lost
• ⚙️ Sync plugin settings across devices: keep this plugin's own settings — and optionally every other installed plugin's settings — in sync between your devices, passphrase-encrypted (the passphrase never leaves your device). Never deletes; conflicts ask which side to keep (see Sync plugin settings across devices)
• ✅ Whole vault or a specific subfolder — toggleable
• ✅ Recursive: subfolders are mirrored; even empty folders are synced
• ✅ Conflict strategy "newer wins" (by timestamp); an edit always beats a deletion (no data loss)
• ✅ Deletion safety: only files that provably existed on both sides get deleted. Local deletions go to Obsidian's .trash folder in the vault, Drive deletions to the Drive trash — never permanent
• ✅ Optional "Do not delete in Google Drive" mode: local deletions are never propagated to Drive
• ✅ Sync tree in the settings: browse all synced folders and files; a checkbox per entry shows whether it exists locally, and files kept only in Drive can be restored locally per entry (auto-refreshes after each sync, plus a manual refresh button)
• ✅ All file types (Markdown, images, PDFs …), optionally narrowed by a file-extension filter
• ✅ Shared Drives (Team Drives) are supported — auto-detected when you pick the folder
• ✅ Live status bar + persistent sync log (viewable in the log window)
• 📱 Works on desktop and mobile. You sign in on desktop, then copy the sign-in token to mobile (mobile can't run the sign-in redirect flow — see Mobile setup)

🛑 DANGER — Please read before first use

This plugin can delete and overwrite files on both sides. Misuse can cause data loss. Take these precautions seriously:

1. ALWAYS create a backup first

Before you run the plugin for the first time (or with a new folder): back up your vault AND your Google Drive folder. Two-way sync is powerful, but any sync software can destroy data when misconfigured. The trash (local .trash, Drive trash) is a safety net — not a substitute for a real backup.

2. NEVER copy sync-state.json into a new or empty vault

The plugin remembers the last sync state in sync-state.json (in the plugin folder). This file belongs exclusively to the vault where it was created.

If you copy this file into a new/empty vault, the plugin will "believe" that all the files it lists were deleted locally — and propagate those deletions to Google Drive. Your Drive folder would be emptied.

The plugin protects you as far as it can (the state file is bound to vault name + Drive folder and is discarded on mismatch). But this protection fails if the new vault happens to use the same name and the same Drive folder. So don't rely on it:

• Set up every vault fresh (install the plugin, sign in, pick the folder) — never copy plugin data around by hand.
• If you move/duplicate a vault and are unsure: delete sync-state.json or click "Reset sync state" in the settings. The next sync will then reconcile cleanly (download) instead of deleting.

3. Test with unimportant data first

For your first run, try the plugin with a throwaway vault and a separate Drive folder before pointing it at your real notes.

How it works (overview)

The plugin keeps a state (the "base") per file and folder: MD5 hash, timestamps, and — crucial for deletion safety — which side the file actually existed on at the last sync (local/remote). On the next run it compares the current local state, the Drive state, and this base:

• File changed only locally → upload
• File changed only in Drive → download
• File changed on both sides → conflict → newer wins
• File now missing on one side:
  • …and the base says it was never there → it's new → gets copied, never deleted
  • …and the base says it existed on both sides → real deletion → propagated to the trash (unless the other side changed it, in which case the edit wins)

This "existed-before" proof prevents the classic sync catastrophe where an empty or foreign state wipes the whole Drive folder. On top of that, the base is bound to vault + Drive folder — a state file copied from another vault is detected and discarded.

Deleted files are never gone permanently: locally they go to Obsidian's .trash folder in the vault, in Drive to the trash.

The full decision table lives in src/reconciler.ts and is covered by unit tests in test/unit/.

Folder structure: the folder hierarchy is mirrored into Drive — subfolders are created and synced (even empty ones). Additionally, each file's vault-relative path is stored in Drive under appProperties.obsidianPath as a fallback.

Setup

1. Create a Google Cloud app (one-time)

New to this / not technical? Follow the illustrated, plain-language guide instead: Step-by-step Google setup — it walks through creating the Google app click by click.

The short version:

1. Open the Google Cloud Console.
2. Create a new project (or pick an existing one).
3. APIs & Services → Library → search for "Google Drive API" → Enable.
4. APIs & Services → OAuth consent screen:
   • Choose user type "External".
   • Enter app name, support email, and developer contact.
   • Add your own Google address under Test users (while the app is in testing mode this is enough — no Google verification required).
5. APIs & Services → Credentials → Create credentials → OAuth client ID:
   • Application type: "Desktop app".
   • After creation you receive a client ID and client secret.

The loopback redirect (http://127.0.0.1:<port>) is automatically allowed for the "Desktop app" type — you don't need to register a redirect URI manually.

Using the plugin on mobile too? No extra OAuth client is needed — you sign in on desktop and copy the token to mobile. See Mobile setup.

2. Install the plugin

Manual (for development/testing):

git clone <this-repo> obsidian-google-drive-mirror
cd obsidian-google-drive-mirror
npm install
npm run build

The build produces a ready-to-install directory .build/ (main.js + manifest.json + styles.css). Copy its contents into your vault under:

<Vault>/.obsidian/plugins/google-drive-mirror/

Enable the plugin in Obsidian under Settings → Community plugins.

3. Configure the plugin

In the plugin settings:

1. Enter the client ID and client secret from step 1.
2. Click "Sign in with Google" → a browser opens → pick your account and grant access. The refresh token is stored automatically.
3. Choose the sync scope: either leave "Sync entire vault" enabled (all files except the .obsidian config folder), or turn it off — then the "Local vault folder" field appears, where you must pick a subfolder (e.g. Notes/Sync).
4. Pick the Google Drive folder: just type in the field — a suggestion list of your Drive folders appears (live search). Click a folder, done. Alternatively paste an existing folder ID and click "Verify", or use the folder-plus button to create a new "Obsidian" folder.
   • You can find the folder ID in the folder's URL in Google Drive: drive.google.com/drive/folders/<THIS-ID>.
   • The Local vault folder field also shows matching vault folders as suggestions while you type.
5. Optionally enable auto-sync and set the interval. Further options: file-extension filter, "Do not delete in Google Drive" (see below), log retention (hours), and debug logging.

Mobile setup (sign in on desktop, copy the token)

The plugin runs on Obsidian mobile (iOS/Android) too, using the same Google account and the same synced data. But mobile can't sign in directly: Google removed the copy-paste (OOB) flow, rejects custom obsidian:// redirects for every client type, and a phone can't run the desktop loopback server. So there is no extra OAuth client to create — instead you move the sign-in token from desktop to mobile:

1. On desktop, sign in normally (enter client ID + secret, click "Sign in with Google").
2. Still on desktop, in the plugin settings click "Copy sign-in token". This copies your refresh token to the clipboard.
3. Get that token onto your phone (paste it into a note that syncs, send it to yourself, a password manager, etc.).
4. On mobile, open the plugin settings, enter the same client ID and secret as on desktop, expand "Sign in with a token from another device", paste the token, and tap "Sign in with token".

That's it — mobile is now signed in and syncs like desktop. The token is account-level, so it works on any device with the same client credentials.

The client ID/secret come from a "Desktop app" OAuth client (the same one from step 1 of the setup). Its secret isn't truly secret for installed apps, so putting it on your phone is expected and fine.

"Do not delete in Google Drive" (optional)

When enabled, deleting a file (or folder) locally will not remove it from Google Drive — the Drive copy is kept, and it does not come back locally on the next sync. Default: off (a local deletion is propagated to Drive's trash).

Sync tree

Below the settings you'll find a sync tree showing all synced folders and files. Each entry has a checkbox:

• Checked (and greyed out) — the entry exists both locally and in Drive (status only, not clickable).
• Unchecked — the entry is kept only in Drive (deleted locally but retained via "Do not delete in Google Drive"). Check it to restore the file locally on the next sync.

The tree auto-refreshes after each sync, and there's a refresh button next to the heading for a manual update. The heading also shows how many entries are currently only in Drive.

Google Workspace files (view-only, optional)

Native Google Workspace files can't be synced as files — they have no downloadable binary, only the live cloud document. With the per-target "Sync Google Workspace files" toggle enabled, the plugin instead creates a small stub note in your vault for each one that embeds the live Google editor. Supported types and their stub suffixes:

(Other Google types — Forms, Sites, etc. — are left as-is.)

• Desktop: the note shows the real, fully editable Google editor inline (it's the actual Google page — your edits save straight to Google, no conversion).
• Mobile: shows an "Open in Google …" button instead (mobile can't embed the editor).

These stub notes are pointers, not content: the file is never downloaded and never uploaded back, and the stubs are excluded from the sync entirely (they're never uploaded to Drive and never treated as deletions). Deleting a stub note doesn't touch the Google file; deleting the Google file doesn't auto-remove the stub. Default: off.

Tip: the embed fills the full note pane width. Sign-in uses your browser's Google session inside the embed.

Sync plugin settings across devices (optional)

A separate feature (its own tab in the settings) that keeps this plugin's own settings — your sync targets, filters, and options — in sync across your devices, so a second desktop or a phone inherits the same setup. It is not part of the folder sync above and never deletes anything.

How it works:

• Its own Drive folder. You pick a dedicated Drive folder; inside it the plugin mirrors the .obsidian structure (e.g. .obsidian/plugins/google-drive-mirror/data.json). Keep it separate from your note folders — the plugin's normal note sync automatically ignores anything under .obsidian, so the two never collide.
• A passphrase you set per device. Everything uploaded is encrypted with a passphrase that you enter on each device and that is never uploaded. Enter the same passphrase on every device. The passphrase is stored locally (obfuscated) so you don't have to re-type it every session and so it can run unattended — see the note below on what that does and doesn't protect.
• Whole-file encryption. Each settings file is encrypted as a single opaque blob, so credentials (and any secrets) are unreadable in Drive.
• Conflicts ask. If a settings file changed on both devices since the last sync, you're prompted to keep this device's version or Drive's. Otherwise the newer one wins. Nothing is ever deleted — a settings file present on only one device is only ever copied to the other.
• Live-applies for this plugin. After a download, this plugin's own settings take effect immediately (no restart).

Also sync other plugins' settings (optional, off by default). A second toggle additionally syncs the data.json of every other installed plugin (only for plugins already installed on both devices — it does not install or enable plugins). Each file is fully passphrase-encrypted, so any secrets other plugins store stay unreadable in Drive. Note: other plugins usually need an Obsidian reload to pick up downloaded settings.

⚠️ On the stored passphrase: it is stored obfuscated and bound to the device, not truly encrypted at rest — anyone with access to your local files could recover it (but they could already read your vault and credentials in that case). What it does guarantee: the passphrase never reaches Drive, so a leak of just the Drive folder cannot decrypt your settings. A settings file copied to another device won't carry a usable passphrase — you re-enter it there.

Trigger it manually with the command "Sync plugin settings now" or the button in the settings tab. It has its own live status line and log, just like the folder sync.

4. Get started

• Manual: ribbon icon (🔄), the command "Google Drive Mirror: Sync now", or click the status bar at the bottom.
• Automatic: with auto-sync enabled, local saves are uploaded after a short delay, and Drive is polled at the configured interval.
• Status & log: the status bar at the bottom shows live progress (⏳ 3/12 …, ✅, ⚠️). Via "Show log" in the settings you see the full, live-updating log.

If you change the Drive folder or the sync scope, the internal sync history is reset automatically, so the next run reconciles cleanly (instead of deleting).

Development

npm install
npm run dev      # esbuild in watch mode (inline sourcemap)
npm run build    # typecheck + production build -> main.js
npm test         # vitest (unit + integration)

Before any change to the sync logic: keep npm test green. The core logic (reconciler, deletion safety, folders) is test-covered.

Architecture:

Performance (large vaults)

Syncing thousands of files is optimized in three ways:

• Hash cache: unchanged files are not re-read or re-hashed. A file's MD5 is only recomputed when its size or modification time changed (like rsync). So the first sync is the slow one; every later sync mostly skips hashing.
• Parallel transfers: uploads and downloads run several at a time (bounded concurrency), which is dramatically faster than one-by-one over the network.
• Automatic retry: transient Google errors (rate limits, server hiccups) are retried with exponential backoff, so large runs don't fail on a single blip.

Interrupting a sync

A sync can be interrupted at any time (closing Obsidian, a crash) — without data loss:

• Files already transferred are fully present on the other side (every upload is atomic, no half files are created).
• Progress is checkpointed every 50 files, plus once at the end. An interruption therefore costs at most the last few files of repeated work.
• The next sync resumes where it was interrupted, transferring only what's missing — files already present are recognized by content comparison and not transferred again.
• Thanks to the hash cache, the next run only re-reads files that actually changed, so re-checking a large vault after an interruption is fast.

Known limitations / to-dos

• Renames are currently handled as delete + re-create (no rename tracking via the Drive ID). Works correctly, but generates unnecessary traffic.
• Large files are transferred via multipart upload in a single request (no resumable upload), and each file is read fully into RAM. For individual very large files (several hundred MB+) this is risky; for many small/medium files it's fine.
• No delta/changes API: Drive is polled via a full listing. For very large folders, the Drive Changes API (changes.list with startPageToken) would reduce the per-sync listing cost further. Deliberately not implemented yet — it requires caching the full remote state between runs, which is high-risk for a data-loss-sensitive plugin.
• Conflict strategy is fixed to "newer wins". A "keep both" option (conflict copy) could be added to the reconciler.

License

MIT