Krzysztof kuhy Rudnicki
24dbffc432
Without this the schedule would be device-local, which is the failure this
whole feature has to avoid: the phone sets five meals, the PC still derives
four, and the PC's gate nags for a 12:00 checkpoint the phone never offered
and can never satisfy. So sync lands before either edit surface, not after.
The history rides the existing `budget` CRDT record as one
`sched:<YYYY-MM-DD>` field per entry, exactly like the budget's own `hist:`
fields. merge_record is per-field LWW over the *union* of field names and both
devices push the merged record, so a device that predates the feature relays
the fields untouched -- no coordinated release. There is a test for precisely
that: merging our push with a budget-only peer keeps both schedule entries.
Verified the two languages agree on the wire, not just in their own suites --
Python and Dart both emit
{"sched:1970-01-01":{"f":8,"l":20,"n":4},"sched:2026-08-16":{"f":8,"l":20,"n":5}}
The Hlc is derived from the *parsed* timestamp on both sides, which matters
because the epoch fallback formats differently in each language
(1970-01-01T00:00:00+00:00 vs ...000Z) and a string comparison would diverge.
Two guards worth naming:
- A device with no history contributes no `sched:` fields at all, so an unset
default can never outrank a peer's real schedule; and an empty merge result
is never written back, so a pre-feature peer cannot erase a real history.
- Dart's `_syncBudget` synthesises a local record when the schedule has been
edited but the budget never has -- `budgetToLog(null, ...)` returns an empty
Log and would otherwise drop the schedule fields too. Its budget value
carries an epoch stamp, so it loses every LWW race against a real edit.
sync_merge/_schedule.py and sync_merge_schedule.dart are separate modules
rather than additions to the budget adapters, which were at 186 and 170 lines
against the 250 cap. Each declares its own record-id constant so the Dart
pair does not import each other.
772 Python tests at 100% branch coverage, 619 Dart.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_0159b4E5hh512jYUeaJVNxfM
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| .. | ||
| .agents/skills | ||
| android | ||
| assets/icon | ||
| bin | ||
| desktop | ||
| lib | ||
| test | ||
| web | ||
| .gitignore | ||
| .metadata | ||
| analysis_options.yaml | ||
| install_arch.sh | ||
| pubspec.lock | ||
| pubspec.yaml | ||
| README.md | ||
| run.sh | ||
| skills-lock.json | ||
diet_guard_app
Companion app for diet_guard: log meals on the phone, and on the Linux
desktop, sharing one food log through GitHub-backed sync.
Two targets, and only two
| Target | What it is |
|---|---|
| Android | a normal Flutter app (flutter build apk) |
| Linux desktop | the Flutter web build, served by a local wrapper and shown in a Chrome --app window |
There is no linux/ directory. Flutter's GTK embedder manages ~20fps at
3840x2160 -- measured on a stock flutter create counter app, so it is the
toolkit rather than this code -- where the same Dart rendered by Chrome
sustains ~144fps (~/todo/docs/desktop-performance-findings.md). Running
flutter create --platforms linux here would silently restore the slow path.
Commands
flutter test # the app's suite
flutter analyze
bash run.sh # build the web bundle and launch the desktop app
bash install_arch.sh # build + install the pacman package and .desktop entry
flutter build apk --release # the phone build
adb install -r build/app/outputs/flutter-apk/app-release.apk
Never adb uninstall or pm clear this package: both wipe the on-device log.
The desktop wrapper
bin/diet_guard_desktop.dart is the other half of the desktop app, because a
browser cannot touch the filesystem. It:
- serves the built web assets from
build/web(or/opt/diet-guard-app/webonce packaged); - keeps an on-disk copy of every document and photo under
~/.local/share/diet-guard-desktop/, which is what makes a wiped Chrome profile recoverable -- for photos it is the only copy, since they never sync; - holds the GitHub token (
~/.config/diet_guard_app/sync_token, falling back to the PC gate's~/.config/diet_guard/sync_token) and proxiesapi.github.complus the device flow, whose endpoints send no CORS headers and so cannot be called from a page at all.
The port (8732) and the Chrome --user-data-dir must stay fixed.
IndexedDB is keyed by origin and lives inside that profile, so changing either
looks to the app like a device with no history.
Platform seams
dart:io does not fail a web compile; it becomes a stub that throws at
runtime, so the symptom of a missed seam is a blank white window rather than a
build error. Every platform edge is a conditional export -- document_store*,
blob_store*, background_tasks*, notification_backend*, token_vault*,
github_client_factory*, attached_image*. Branch on kIsWeb before any
Platform.is…, which itself throws on web.
What the desktop genuinely loses, by design rather than omission:
- Background reminders. A browser runs nothing once its window is closed,
so the due-slot check runs in-page every 5 minutes while the window is open.
On the PC the real backstop is
diet-guard-gate.timer, which locks the screen. - Camera capture. The browser picker is a file input.
- Photo sharing between devices -- unchanged:
imagePathwas always stripped before push.
Sync identity
Three devices push under diet-guard-sync/devices/: pc (the Python gate),
phone, and desktop. Each must keep its own id -- two devices sharing one
would overwrite each other's pushed log on every tick.