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SPECS — Nils' MG4

Journal for this fork of fatihdonmezdev/FatihsMG4: what has been changed, and what is still to do.

Plan: car server at car.stinnesbeck.com

The car sends everything to our own server. The server stores it and forwards live telemetry to ABRP, so the ABRP token lives only on the server, never in the APK.

car ──live telemetry───▶ car.stinnesbeck.com ──▶ ABRP  api.iternio.com/1/tlm/send
    ──daily totals─────▶          │
    ──charging sessions▶          ▼
                              InfluxDB 2

Server — extend web/ (Next.js)

  • Storage: MongoDB → InfluxDB 2. Rewrite web/src/lib/mongo.ts / data.ts against one bucket (tag installationId on every point):

    Measurement Timestamp Tags Fields
    telemetry sample time — soc, power, speed, lat, lon, heading, elevation, is_charging, is_dcfc, is_parked, capacity, soe, odometer, est_battery_range, batt_temp, cabin_temp, ext_temp, hvac_setpoint, voltage, current, tire_pressure_fl/fr/rl/rr
    consumption_daily the day, 00:00 UTC — km, kwh, hours, socDrop, sohPercent
    charging_session startedAt sessionId endedAt, durationSeconds, energyKwh, gridEnergyKwh, pricePerKwh, totalCost, start/endSocPercent
    charging_curve point time sessionId powerKw, socPercent

    Same measurement + tags + timestamp overwrites, so the car's retries stay idempotent (MongoDB used unique indexes for that).

  • New endpoint POST /v1/telemetry: a batch of live samples, ingest-token auth, validated and bounded like the existing endpoints.

  • ABRP forwarder: after storing, forward the newest sample to tlm/send with ABRP_API_KEY and ABRP_USER_TOKEN from the environment. Rate-limited; a failed forward is logged but not retried, since stale live data is useless to ABRP. Off when the token is unset.

  • Existing endpoints stay: PUT /v1/consumption/daily, PUT /v1/charging-sessions/:id, GET /v1/consumption/history/:id, the dashboard and /v1/health.

  • Self-hosting: drop the Vercel assumptions, output: "standalone", a Dockerfile, and ensureIndexes() replaced by bucket checks at startup.

Car app

  • Restore the live telemetry payload and upload cadence from before ea8032a (TelemetryPayload, UploadCadence, location access), sending to the server instead of ABRP.
  • Server URL and ingest token: open question, see below.
  • Generate our own CONSUMPTION_INSTALLATION_ID.

Image and deployment

  • Image: git.stinnesbeck.com/nils/mg4-server:<version>, pushed to the forge's registry (needs a registry login on the build machine).
  • k8s/ with plain manifests: Namespace, InfluxDB StatefulSet + PVC + Service (cluster-internal), server Deployment + Service + Ingress for car.stinnesbeck.com (TLS), and Secret templates with placeholder values only.
  • Nothing is ever applied to the cluster by us. Nils applies the manifests.

Open questions

  • Run InfluxDB inside the cluster from our manifests (assumed), or use an existing instance?
  • Ingress class and TLS setup (e.g. cert-manager ClusterIssuer name), or an existing wildcard certificate Secret?
  • Car config: bake the server URL and ingest token into the APK at build time (as upstream does), or enter them in the app, which restores the settings tab with the config-file import? In the app keeps the token out of the APK.
  • ABRP API key: the open-source default key from upstream, or our own?

To do

  • About dialog link and QR code → https://git.stinnesbeck.com/nils/mg4. Both come from REPOSITORY_URL in app/src/main/java/com/evsuite/abrp/MainActivity.java and about_repository in app/src/main/res/values/strings.xml. They still point to Fatih's GitHub repository.
  • Re-enable OTA updates against our own releases. RELEASES_API in app/src/unstable/java/com/evsuite/abrp/OtaUpdater.java points at updates.invalid on purpose, so checks fail. The updater speaks the GitHub releases API and only allows GitHub hosts (ALLOWED_HOSTS). For git.stinnesbeck.com it needs the host on the allowlist, and the response parsing checked against that server's releases API. Release assets must be named NilsMG4-unstable-<version>.apk with a .sha256 sidecar (build-car writes both).
  • ABRP upload is gone upstream. Upstream commit ea8032a ("chore", 2026-10-09) removed the ABRP tab, the config-file import (ConfigImport), the upload (AbrpApi, TelemetryPayload, UploadCadence), SecurePrefs and HeadUnitWeather. The app now only tracks consumption and syncs it to the MongoDB API. Leftover strings.xml entries (btn_import, import_*, hint_api_key, …) belong to it. Decide whether to restore it.
  • Fix the unit tests. They don't compile upstream: AbrpApiTest, TelemetryPayloadTest and others still use AbrpApi/TelemetryPayload, which upstream commit ea8032a deleted.
  • Charging currency. Prices and costs are shown in Turkish lira (₺/kWh, ₺) in pane_charging.xml and MainActivity.java.
  • Cloud consumption sync. CONSUMPTION_INSTALLATION_ID in app/build.gradle is a fixed UUID inherited from upstream. Set our own before configuring CONSUMPTION_API_URL / CONSUMPTION_API_TOKEN, so our data cannot land under upstream's id.
  • Translate the rest. The web/ dashboard (Next.js) and docs (CHANGELOG.md, OTA.md's message table, comments in mise.toml/app/build.gradle) are still Turkish or French.
  • Docs still use the old package ID. README.md, OTA.md, CHANGELOG.md, mise.toml and docs/MG4_PLATFORM_INSTALL.md refer to com.evsuite.abrp(.unstable) and FatihsMG4-*.apk.
  • Move hardcoded UI strings into strings.xml. Many are inline in Java and layouts.

Done

  • 2026-10-17 — Translated the app UI from Turkish to English.
  • 2026-10-17 — Nix flake: nix develop provides JDK 21 and the Android SDK. build-car builds the unstable APK and signs it with the AOSP test platform key, which the MG4 head unit uses (cert SHA-256 c8a2e9bc…192ab8).
  • 2026-10-17 — OTA update checks disabled by pointing at an unresolvable host (see To do).
  • 2026-10-17 — Renamed to "Nils' MG4": package ID com.stinnesbeck.nilsmg4 (.unstable for the car build), APK names NilsMG4-*.apk. It installs next to the old FatihsMG4 app instead of replacing it, and starts with empty settings and history.
  • 2026-10-17 — Temporary on-screen diagnostics (b2a5b32) to debug blank values without adb; removed again (1002962) once values showed on the car. Revert 1002962 to bring them back.

Installing on the car

nix develop
build-car
adb push build/car/NilsMG4-unstable-<version>.apk /data/local/tmp/update.apk
adb shell "pm install -r -f -d -t /data/local/tmp/update.apk"

To remove the old upstream app: adb uninstall com.evsuite.abrp.unstable.