# guideCity Android walking city-guide app. Detects the user's location, finds nearby landmarks, and narrates historical/architectural information about them by voice while showing a swipeable card stack. Starting city: Moscow. ## Architecture ``` ┌────────────────────┐ │ Android app │ Kotlin + Jetpack Compose │ (android/) │ 2GIS map, on-device TTS, └─────────┬──────────┘ location, Room favorites │ HTTPS / REST (JSON) ┌─────────▼──────────┐ │ FastAPI backend │ Python, SQLAlchemy, Alembic │ (backend/) │ Dockerized └─────────┬──────────┘ │ SQL ┌─────────▼──────────┐ │ PostgreSQL+PostGIS │ cities / places / place_content └────────────────────┘ ``` - `backend/` — FastAPI service exposing city/place/nearby-search endpoints, backed by PostgreSQL+PostGIS. See `backend/` for details. - `android/` — Kotlin/Compose app skeleton (MVVM, Hilt, Retrofit, Room, DataStore, 2GIS MapKit, on-device TextToSpeech). ## Backend quickstart ```bash cp .env.example .env docker compose up -d db docker compose exec api alembic upgrade head # (once api image is built: docker compose up -d --build api adminer first) docker compose exec api python -m seed.seed_loader --file seed/moscow_gorky_park.yaml docker compose exec api python -m seed.seed_loader --file seed/moscow_red_square.yaml docker compose exec api python -m seed.seed_loader --file seed/moscow_city.yaml curl http://localhost:8000/api/v1/health curl "http://localhost:8000/api/v1/nearby?lat=55.7525&lon=37.6231" ``` Swagger UI: http://localhost:8000/docs Adminer (DB inspection): http://localhost:8080 The `api` service binds `0.0.0.0:8000` (see `docker-compose.yml`), so it's also reachable from other devices on the same LAN at `http://:8000/` — no extra config needed, just make sure nothing (firewall, VPN) blocks port 8000 on that interface. It's also reverse-proxied behind nginx at **https://guidetest.vrubel.xyz/**, which works from anywhere (not just the local network) and is the preferred `API_BASE_URL` for the Android app during this test phase. ## Android quickstart ```bash cp android/local.properties.example android/local.properties # fill in sdk.dir and DGIS_API_KEY (test key: b4df01a8-61db-4cb9-8286-7e069495987d) cd android && ./gradlew :app:assembleDebug ``` Point the app's API base URL (`API_BASE_URL` in `local.properties`) at `https://guidetest.vrubel.xyz/` (works from anywhere), `http://10.0.2.2:8000/` for the emulator, or your machine's LAN IP for a physical device on the same Wi-Fi/LAN. Run unit tests before building — `./gradlew testDebugUnitTest`, then `./gradlew :app:assembleDebug`. ## 2GIS map SDK The app depends on the real 2GIS MapKit SDK (`ru.dgis.sdk:sdk-map` + `compose-map`, from `https://artifactory.2gis.dev/sdk-maven-release`, wired up in `settings.gradle.kts`/`app/build.gradle.kts`). It needs a **separate** key from the `DGIS_API_KEY` above: - `DGIS_API_KEY` (the `b4df01a...` value) is a 2GIS **public REST/JS API** key — not used by the native SDK at all currently. - The native MapKit SDK instead needs a **`dgissdk.key` file**, issued per-app (tied to the package name `com.guidecity.app`) from https://dev.2gis.com/. Place it at `android/app/src/main/assets/dgissdk.key` (gitignored — don't commit it). Without that key file, `DgisSdkProvider` fails to initialize (logged, not crashed) and `DgisMapView` falls back to a placeholder canvas rendering (user location + nearby place dots, no real map tiles). Once a real key is in place, the real map should render automatically — no code changes needed. Also note: the SDK bundles native libraries per CPU architecture, which balloons APK size a lot (~19MB → ~190MB unfiltered). `app/build.gradle.kts` restricts `ndk.abiFilters` to `arm64-v8a` only (~69MB) since that covers virtually all real devices today — remove that filter if you need to test on an x86 emulator or 32-bit device. ## Notes / current scope This is iteration 1: Moscow only (Gorky Park, Red Square area, Moscow-City), no user accounts (favorites are local/Room-only), no speed/heading-aware auto content-length selection yet (reserved API params exist, unused). Nearby-search radius caps at 10km. Place markers aren't yet plotted on the real 2GIS map (only the placeholder does that) — follow-up work. The 2GIS REST/JS API key above is used directly via `local.properties`/`BuildConfig` for development convenience — don't ship it as-is in a public repo. Same goes for `dgissdk.key` once you have one.