Files
mg4/OTA.md
T
TCFDONMEZandClaude Opus 5 288e2bf026 docs: point OTA.md at the MG copy of the platform keys
Two byte-identical copies of the platform key live on this machine, under
LUMINA/DriveHub_Kamera/tools and MG/DriveHub_Kamera/tools. OTA.md named the
LUMINA one; the MG one sits inside this workspace and is the copy actually
reached for.

Both work today only because someone keeps them in sync by hand. A private
signing key duplicated across two directories, with a checked-in document
pointing at one of them, is worth collapsing to a single location.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-09-25 14:03:18 +03:00

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# Publishing an OTA release
How to ship an update the car will install by itself. Written for whoever does this
next — probably me, having forgotten the details.
## What the updater actually looks for
`OtaUpdater.check()` reads `https://api.github.com/repos/fatihdonmezdev/MG4ABRP/releases`
and walks **every** entry, keeping the highest version rather than the first match. A
release is a candidate only if all of these hold:
| Requirement | Where it is enforced | What happens otherwise |
|---|---|---|
| Marked **pre-release** | `release.optBoolean("prerelease")` | Skipped entirely |
| Asset name contains `unstable` | `name.contains("unstable")` | Asset ignored |
| Asset name ends `-<version>.apk` | `ASSET_VERSION` regex | No version, asset ignored |
| Version strictly higher than installed | `isNewer()` | Nothing to do, reports "Güncel" |
| Download host on the allowlist | `isAllowedUrl()` | Refused and logged |
| APK signed with the **same certificate** as the running app | `signatureMatchesRunningApp()` | Deleted, never installed |
The last one is the one that bites. The car runs a platform-signed build; an APK signed
with a debug key — or anyone else's key — is downloaded, rejected and deleted. Sign every
release with the same platform key or the update silently never lands.
The version comes from the **asset filename**, not the git tag. The tag can stay
`unstable` forever and be moved; the filename is what identifies a build.
## Release checklist
1. **Raise the version.** `app/build.gradle`, `defaultConfig`:
```gradle
versionCode 20 // must increase — Android orders updates by this, not by name
versionName "2.2.3"
```
The unstable flavour appends its own suffix, so `2.2.3` becomes `2.2.3.0-unstable`.
Check what the installed build reports before picking a number: the app's About
dialog shows it, and `isNewer` compares numerically segment by segment.
2. **Build.**
```bash
./gradlew :app:assembleUnstableDebug
```
3. **Sign with the platform key.** Options come *before* the input APK — apksigner
rejects the other order.
```bash
BT=~/Android/Sdk/build-tools/35.0.0
KEYS=~/Desktop/Coding/MG/DriveHub_Kamera/tools
"$BT/zipalign" -f 4 \
app/build/outputs/apk/unstable/debug/app-unstable-debug.apk aligned.apk
"$BT/apksigner" sign \
--key "$KEYS/platform.pk8" \
--cert "$KEYS/platform.x509.pem" \
--out FatihsMG4-unstable-2.2.3.apk \
aligned.apk
rm aligned.apk
```
The output filename **is** the version the updater reads. Name it
`FatihsMG4-unstable-<version>.apk` and nothing else.
4. **Verify the signer** before uploading. It must say `CN=Android`:
```bash
"$BT/apksigner" verify --print-certs FatihsMG4-unstable-2.2.3.apk | grep DN:
```
5. **Publish.** On github.com/fatihdonmezdev/MG4ABRP → Releases → Draft a new release:
- tag: `unstable` (reuse it; the rolling tag is the design)
- **tick "Set as a pre-release"** ← the whole thing is inert without this
- attach the signed APK
6. **Install it.** Open the app on the head unit and press the refresh button in the top
bar. Expected toast: `Güncellendi: 2.2.3 — yeniden başlatın`.
## When it says something else
| Toast | Meaning |
|---|---|
| `Güncel (2.2.2.0-unstable)` | No release beat the installed version. Check the pre-release tick and the asset filename. |
| `İndirme başarısız` | Release found, download did not complete. Usually no network. |
| `Kuruluyor: 2.2.3 — ekrandaki onayı bekleyin` | The session was committed. Not done yet: watch for the platform's own toast, or a confirmation dialog to accept. |
| `Kurulum reddedildi: imza uyuşmuyor` | Genuinely the wrong key — rebuild and re-sign with `platform.pk8`. Unlike the old catch-all, this one means what it says. |
| `Kurulum reddedildi: APK okunamadı` | The archive does not parse, or it is built for another package. |
| `Kurulum başlatılamadı … Log sayfasına bakın` | The session could not be created or committed. `adb logcat -s EVABRP.Update`. |
| `Kurulum başarısız: INSTALL_FAILED_…` | From `OtaInstallResultReceiver` — the package manager's own words for why it refused. |
| `Güncelleme kontrolü başarısız` | The check threw. `adb logcat -s EVABRP.Update OtaUpdater` if a cable is available; otherwise the in-app Log page. |
## How the install works, and why it is not `pm install`
`OtaUpdater.install()` used to shell out to `/system/bin/pm install -r`. On this head unit
that fails every time, and the reason is worth writing down because the symptom pointed
somewhere else entirely.
The downloaded APK lives in `context.getCacheDir()`. `pm` does not install the file itself
— it passes the path to the package manager service, which opens it from *its* process and
SELinux context, where an app's private cache is not readable. The install failed, and
because `install()` returned a bare boolean, the caller reported the only failure it knew
how to name: `Kurulum reddedildi (imza uyuşmuyor?)`. A correctly signed build, refused with
a signature error it had not earned. The `pm` output that would have said so was captured
and thrown away.
It now uses the platform `PackageInstaller`: we open the archive ourselves and stream it
into a session, so no second process ever has to read our cache. The approach is taken from
[merthankaraman/DriveHub_Dort](https://github.com/merthankaraman/DriveHub_Dort), which hit
the same wall on the same hardware.
Two consequences for anyone reading a failure:
- **Committing a session is not installing.** `commit()` is asynchronous. The refresh button
can only report that an install *started*; the verdict arrives at
`OtaInstallResultReceiver` and appears as its own toast.
- **`STATUS_PENDING_USER_ACTION` is not an error.** The platform is asking the driver to
confirm. The receiver launches the confirmation activity the platform hands it.
Still unverified on the car: whether this build installs silently or raises that
confirmation. Either way it installs, which the old path did not.
## Why the check is manual
The refresh button is the only trigger. `UpdateHook.checkInBackground(this)` also runs on
app start, but the app is rarely launched — the upload service does the work, and the
driver does not open the UI on every trip. The button is there so an update can be pulled
deliberately rather than waiting for a launch that may not come.
The upload service does **not** check for updates on its tick. Installing a new APK
restarts the process, and doing that mid-drive would interrupt the telemetry the service
exists to send.