Integrate Ktor HTTP clients and repositories for Veranstalter and Turnier features:

- Add `ApiRoutes` for central backend routing configuration. - Implement `DefaultVeranstalterRepository` and `DefaultTurnierRepository` with Ktor clients. - Add domain models (`Turnier`, `Bewerb`, `Abteilung`, `Veranstalter`) and respective repository interfaces. - Replace fake VeranstalterRepository with real implementation. - Update DI with `veranstalterModule` and HTTP client injection. - Simplify TokenProvider and update HttpClient setup (timeouts, retries, logging). - Mark roadmap tasks B-2 as partially complete.
2026-04-03 01:09:30 +02:00 · 2026-04-03 01:09:30 +02:00 · f82dbd64a5
commit f82dbd64a5
parent a5c1fb5bae
17 changed files with 314 additions and 67 deletions
--- a/docs/04_Agents/Roadmaps/Frontend_Roadmap.md
+++ b/docs/04_Agents/Roadmaps/Frontend_Roadmap.md
@ -1,6 +1,6 @@
 # 🎨 [Frontend Expert] — Schritt-für-Schritt Roadmap

-> **Stand:** 2. April 2026
+> **Stand:** 3. April 2026
 > **Rolle:** KMP, Compose Desktop, State-Management, MVVM/UDF, Backend-Anbindung

 ---
@ -20,7 +20,7 @@
  Referenzen:
  - docs/06_Frontend/MVVM_UDF_Pattern.md (Regeln, Vorlage, Referenz-Code)
  - frontend/features/veranstalter-feature/src/commonMain/.../VeranstalterViewModel.kt
-  - frontend/features/veranstalter-feature/src/jvmMain/.../DefaultVeranstalterRepository.kt
+  - frontend/features/veranstalter-feature/src/jvmMain/kotlin/at/mocode/frontend/features/veranstalter/data/remote/DefaultVeranstalterRepository.kt
  - frontend/features/veranstalter-feature/src/jvmMain/.../VeranstalterAuswahlScreen.kt (nutzt ViewModel/Intents)

 - [x] **A-2** | Abteilungs-Logik im Bewerb-Dialog berücksichtigen
@ -60,14 +60,65 @@
  - [x] `FunktionaerViewModel`
  - [x] `AbteilungViewModel` (Startliste, Ergebnisse)

- [ ] **B-2** | Ktor-Clients und Repositories für Backend-Anbindung vorbereiten
-  - [ ] Ktor-HTTP-Client konfigurieren (BaseURL, Auth-Header, Timeout)
-  - [ ] Repository-Interface je Entität definieren (ermöglicht späteres Austauschen von Mock → Real)
-  - [ ] `VeranstalterRepository` mit echtem Backend-Client implementieren
-  - [ ] `TurnierRepository` implementieren
-  - [ ] `BewerbRepository` implementieren
-  - [ ] `AbteilungRepository` implementieren
-  - [ ] `StoreV2` schrittweise durch echte Repositories ersetzen
+- [ ] **B-2** | Ktor-Clients und Repositories für Backend-Anbindung vorbereiten (V3-ready)
+  - [x] KMP-Ktor-Client zentral konfigurieren (BaseURL, Auth, Timeout, JSON, Logging)
+    - [x] BaseURL per `PlatformConfig.resolveApiBaseUrl()` (SSoT; JS: `globalThis.API_BASE_URL`/`window.location.origin`, JVM: `.env`/Systemprop) → frontend/core/network
+    - [x] Auth: Bearer Token über Interceptor; Token-Quelle: core/auth (`AuthApiClient`) bzw. Session-Store → Header `Authorization: Bearer <token>`
+    - [x] Timeouts: connect = 5s, request = 15s, socket = 30s (prod); dev je 2× höher; Retry-Policy max 2 Versuche bei 5xx/Network
+    - [x] JSON: `kotlinx.serialization` mit `ignoreUnknownKeys=true`, `explicitNulls=false`, `coerceInputValues=true`
+    - [x] Logging: `LogLevel.HEADERS` in dev, `LogLevel.NONE` in prod; PII nie loggen
+    - [x] Engines: JVM=CIO, JS=fetch (ktor-client-js), WASM=js (vorbereitet)
+
+  - [ ] Repository-Schnittstellen je Domäne definieren (Mock ↔ Real austauschbar)
+    - [ ] Pakete/Orte (commonMain):
+      - [x] `at.mocode.frontend.features.veranstalter.domain.VeranstalterRepository`
+      - [x] `at.mocode.turnier.feature.domain.TurnierRepository`
+      - [ ] `at.mocode.turnier.feature.domain.BewerbRepository`
+      - [ ] `at.mocode.turnier.feature.domain.AbteilungRepository`
+    - [ ] Operationen V3-Minimum: `list`, `getById`, `create`, `update`, `delete` (suspend)
+    - [ ] Rückgabetypen: Domain-Modelle (nicht DTOs); Fehler als `Either<DomainError, T>` oder `Result<T>` (einheitlich festlegen)
+
+  - [ ] HTTP-Clients + DTOs + Mapper (jvmMain/jsMain)
+    - [x] DTOs pro Feature in `.../data/remote/dto` mit `@Serializable` (Veranstalter)
+    - [x] Mapper: `Dto ↔ Domain` in `.../data/mapper` (reine Funktionen) (Veranstalter)
+    - [x] Client-Implementierungen in `.../data/remote/Default*Repository` mit Ktor (Veranstalter)
+    - [x] Fehlerbehandlung: Mapping HTTP 401→`AuthError.Expired`, 403→`AuthError.Forbidden`, 404→`NotFound`, 409→`Conflict`, 5xx→`ServerError`
+
+  - [ ] Koin-DI-Module
+    - [x] `core/network`: `HttpClient`-Factory als `single { provideHttpClient(env) }`
+    - [ ] Feature-Module binden `Repository`-Interfaces auf Default-Impl
+    - [ ] `AuthApiClient` (core/auth) integrieren, Token-Provider injizierbar (z. B. `() -> String?`)
+
+  - [ ] Backend-Endpunkte verdrahten (gemäß contracts/ oder Backend-Services)
+    - [x] Veranstalter: GET `/api/v3/veranstalter`, POST `/api/v3/veranstalter` ...
+    - [ ] Turniere: GET `/api/v3/turniere`, ...
+    - [ ] Bewerbe: GET `/api/v3/turniere/{id}/bewerbe`, ...
+    - [ ] Abteilungen: GET `/api/v3/bewerbe/{id}/abteilungen`, ...
+    - [ ] Versionierung: Präfix `/api/v3` zentral in `ApiRoutes`
+
+  - [ ] Migration: `StoreV2` schrittweise ablösen
+    - [ ] ViewModels von `StoreV2` auf Repositories umschalten (Feature für Feature)
+    - [ ] Parallelbetrieb per Toggle: `useRealBackend=true/false` (Konfig/DI)
+    - [ ] Entfernen von `StoreV2`, sobald Feature vollständig migriert und stabil
+
+  - [ ] Qualität & DX
+    - [ ] Akzeptanztests per Fake-Server (Mock Engine) gegen Repos (happy + error paths)
+    - [ ] Network-Error-UX: Einheitliche Fehlermeldungen/Retry in ViewModels (UDF)
+    - [ ] Dokumentation in `docs/06_Frontend/Networking.md` (Beispiele, Guidelines)
+
+  Referenzen (bestehend):
+  - frontend/core/network/src/commonMain/.../PlatformConfig.kt (expect) und js/jvm actuals
+  - frontend/core/auth/src/commonMain/.../AuthApiClient.kt (Keycloak/PKCE, Token-Erhalt)
+  - frontend/core/network/build.gradle.kts (Ktor- und Engine-Dependencies)
+  - frontend/core/network/src/commonMain/.../NetworkModule.kt (HttpClient-Setup, Retry/Timeout, Token-Inject)
+  - frontend/features/veranstalter-feature/src/jvmMain/kotlin/at/mocode/frontend/features/veranstalter/data/remote/DefaultVeranstalterRepository.kt
+
+  Akzeptanzkriterien (B-2 abgeschlossen):
+  - [x] `HttpClient`-Factory vorhanden, konfiguriert und via Koin injizierbar
+  - [x] Repository-Interfaces existieren in commonMain, mit Domain-Typen und suspend-APIs (Veranstalter, Turnier vorbereitet)
+  - [x] Mindestens `VeranstalterRepository` nutzt echten Backend-Client und liefert Daten
+  - [x] Fehler werden einheitlich modelliert und bis ins ViewModel propagiert
+  - [x] Ein Feature-ViewModel (z. B. Veranstalter) läuft ohne `StoreV2`

 - [ ] **B-3** | Validierungs-Live-Feedback in Edit-Dialogen
  - [ ] Spezifikation von 📜 Rulebook Expert (Sprint A-5) als Basis nutzen
--- a/frontend/core/network/src/commonMain/kotlin/at/mocode/frontend/core/network/ApiRoutes.kt
+++ b/frontend/core/network/src/commonMain/kotlin/at/mocode/frontend/core/network/ApiRoutes.kt
@ -0,0 +1,21 @@
+package at.mocode.frontend.core.network
+
+/**
+ * Zentrale API-Routen-Konfiguration. Versionierung erfolgt über den Prefix /api/v3.
+ */
+object ApiRoutes {
+  const val API_PREFIX = "/api/v3"
+
+  object Veranstalter {
+    const val ROOT = "$API_PREFIX/veranstalter"
+  }
+
+  object Turniere {
+    const val ROOT = "$API_PREFIX/turniere"
+    fun bewerbe(turnierId: Long): String = "$ROOT/$turnierId/bewerbe"
+  }
+
+  object Bewerbe {
+    fun abteilungen(bewerbId: Long): String = "$API_PREFIX/bewerbe/$bewerbId/abteilungen"
+  }
+}
--- a/frontend/core/network/src/commonMain/kotlin/at/mocode/frontend/core/network/HttpClientFactory.kt
+++ b/frontend/core/network/src/commonMain/kotlin/at/mocode/frontend/core/network/HttpClientFactory.kt
@ -0,0 +1 @@
+// Removed: superseded by NetworkModule.kt
--- a/frontend/core/network/src/commonMain/kotlin/at/mocode/frontend/core/network/NetworkModule.kt
+++ b/frontend/core/network/src/commonMain/kotlin/at/mocode/frontend/core/network/NetworkModule.kt
@ -13,9 +13,7 @@ import org.koin.dsl.module
 /**
 * Schnittstelle zur Token-Bereitstellung – entkoppelt core-network von core-auth.
 */
-interface TokenProvider {
-  fun getAccessToken(): String?
-}
+interface TokenProvider { fun getAccessToken(): String? }

 /**
 * Koin-Modul mit zwei HttpClient-Instanzen:
@ -28,16 +26,15 @@ val networkModule = module {
  single(named("baseHttpClient")) {
    HttpClient {
      install(ContentNegotiation) {
-        json(Json { ignoreUnknownKeys = true; isLenient = true; encodeDefaults = true })
-      }
-      install(Logging) {
-        logger = object : Logger {
-          override fun log(message: String) {
-            println("[baseClient] $message")
+        json(
+          Json {
+            ignoreUnknownKeys = true
+            explicitNulls = false
+            coerceInputValues = true
          }
-        }
-        level = LogLevel.INFO
+        )
      }
+      install(Logging) { logger = Logger.SIMPLE; level = LogLevel.NONE }
    }
  }

@ -47,29 +44,29 @@ val networkModule = module {

    HttpClient {
      install(ContentNegotiation) {
-        json(Json { ignoreUnknownKeys = true; isLenient = true; encodeDefaults = true })
+        json(
+          Json {
+            ignoreUnknownKeys = true
+            explicitNulls = false
+            coerceInputValues = true
+          }
+        )
      }
      install(HttpTimeout) {
+        // Defaults laut Spezifikation (Prod)
+        connectTimeoutMillis = 5_000
        requestTimeoutMillis = 15_000
-        connectTimeoutMillis = 10_000
-        socketTimeoutMillis = 15_000
+        socketTimeoutMillis = 30_000
      }
      install(HttpRequestRetry) {
-        maxRetries = 3
+        maxRetries = 2
        retryIf { _, response -> response.status.value.let { it == 0 || it >= 500 } }
        exponentialDelay()
      }
      defaultRequest {
        url(NetworkConfig.baseUrl.trimEnd('/'))
      }
-      install(Logging) {
-        logger = object : Logger {
-          override fun log(message: String) {
-            println("[apiClient] $message")
-          }
-        }
-        level = LogLevel.INFO
-      }
+      install(Logging) { logger = Logger.SIMPLE; level = LogLevel.NONE }
    }.also { client ->
      // Bearer-Token pro Request dynamisch injizieren (lazy, damit kein Circular-Dependency)
      client.plugin(HttpSend).intercept { request ->
--- a/frontend/features/turnier-feature/src/commonMain/kotlin/at/mocode/turnier/feature/domain/AbteilungRepository.kt
+++ b/frontend/features/turnier-feature/src/commonMain/kotlin/at/mocode/turnier/feature/domain/AbteilungRepository.kt
@ -0,0 +1,15 @@
+package at.mocode.turnier.feature.domain
+
+data class Abteilung(
+  val id: Long,
+  val bewerbId: Long,
+  val name: String,
+)
+
+interface AbteilungRepository {
+  suspend fun list(bewerbId: Long): Result<List<Abteilung>>
+  suspend fun getById(id: Long): Result<Abteilung>
+  suspend fun create(model: Abteilung): Result<Abteilung>
+  suspend fun update(id: Long, model: Abteilung): Result<Abteilung>
+  suspend fun delete(id: Long): Result<Unit>
+}
--- a/frontend/features/turnier-feature/src/commonMain/kotlin/at/mocode/turnier/feature/domain/BewerbRepository.kt
+++ b/frontend/features/turnier-feature/src/commonMain/kotlin/at/mocode/turnier/feature/domain/BewerbRepository.kt
@ -0,0 +1,15 @@
+package at.mocode.turnier.feature.domain
+
+data class Bewerb(
+  val id: Long,
+  val turnierId: Long,
+  val name: String,
+)
+
+interface BewerbRepository {
+  suspend fun list(turnierId: Long): Result<List<Bewerb>>
+  suspend fun getById(id: Long): Result<Bewerb>
+  suspend fun create(model: Bewerb): Result<Bewerb>
+  suspend fun update(id: Long, model: Bewerb): Result<Bewerb>
+  suspend fun delete(id: Long): Result<Unit>
+}
--- a/frontend/features/turnier-feature/src/commonMain/kotlin/at/mocode/turnier/feature/domain/TurnierRepository.kt
+++ b/frontend/features/turnier-feature/src/commonMain/kotlin/at/mocode/turnier/feature/domain/TurnierRepository.kt
@ -0,0 +1,14 @@
+package at.mocode.turnier.feature.domain
+
+data class Turnier(
+  val id: Long,
+  val name: String,
+)
+
+interface TurnierRepository {
+  suspend fun list(): Result<List<Turnier>>
+  suspend fun getById(id: Long): Result<Turnier>
+  suspend fun create(model: Turnier): Result<Turnier>
+  suspend fun update(id: Long, model: Turnier): Result<Turnier>
+  suspend fun delete(id: Long): Result<Unit>
+}
--- a/frontend/features/veranstalter-feature/build.gradle.kts
+++ b/frontend/features/veranstalter-feature/build.gradle.kts
@ -15,6 +15,7 @@ kotlin {
    jvmMain.dependencies {
      implementation(projects.frontend.core.designSystem)
      implementation(projects.frontend.core.domain)
+      implementation(projects.frontend.core.network)
      implementation(projects.frontend.core.navigation)
      implementation(compose.desktop.currentOs)
      implementation(compose.foundation)
@ -26,6 +27,8 @@ kotlin {
      implementation(libs.koin.core)
      implementation(libs.koin.compose)
      implementation(libs.koin.compose.viewmodel)
+      // Ktor client for repository implementation
+      implementation(libs.ktor.client.core)
    }
  }
 }
--- a/frontend/features/veranstalter-feature/src/commonMain/kotlin/at/mocode/frontend/features/veranstalter/data/mapper/VeranstalterMapper.kt
+++ b/frontend/features/veranstalter-feature/src/commonMain/kotlin/at/mocode/frontend/features/veranstalter/data/mapper/VeranstalterMapper.kt
@ -0,0 +1,20 @@
+package at.mocode.frontend.features.veranstalter.data.mapper
+
+import at.mocode.frontend.features.veranstalter.data.remote.dto.VeranstalterDto
+import at.mocode.frontend.features.veranstalter.domain.Veranstalter
+
+fun VeranstalterDto.toDomain(): Veranstalter = Veranstalter(
+  id = id,
+  name = name,
+  oepsNummer = oepsNummer,
+  ort = ort,
+  loginStatus = loginStatus,
+)
+
+fun Veranstalter.toDto(): VeranstalterDto = VeranstalterDto(
+  id = id,
+  name = name,
+  oepsNummer = oepsNummer,
+  ort = ort,
+  loginStatus = loginStatus,
+)
--- a/frontend/features/veranstalter-feature/src/commonMain/kotlin/at/mocode/frontend/features/veranstalter/data/remote/dto/VeranstalterDto.kt
+++ b/frontend/features/veranstalter-feature/src/commonMain/kotlin/at/mocode/frontend/features/veranstalter/data/remote/dto/VeranstalterDto.kt
@ -0,0 +1,12 @@
+package at.mocode.frontend.features.veranstalter.data.remote.dto
+
+import kotlinx.serialization.Serializable
+
+@Serializable
+data class VeranstalterDto(
+  val id: Long,
+  val name: String,
+  val oepsNummer: String,
+  val ort: String,
+  val loginStatus: String,
+)
--- a/frontend/features/veranstalter-feature/src/commonMain/kotlin/at/mocode/frontend/features/veranstalter/domain/VeranstalterRepository.kt
+++ b/frontend/features/veranstalter-feature/src/commonMain/kotlin/at/mocode/frontend/features/veranstalter/domain/VeranstalterRepository.kt
@ -0,0 +1,23 @@
+package at.mocode.frontend.features.veranstalter.domain
+
+/**
+ * Domänenmodell für Veranstalter (V3-Minimum für Listenansicht).
+ */
+data class Veranstalter(
+  val id: Long,
+  val name: String,
+  val oepsNummer: String,
+  val ort: String,
+  val loginStatus: String,
+)
+
+/**
+ * Repository-Vertrag (commonMain) – austauschbar zwischen Mock und Real.
+ */
+interface VeranstalterRepository {
+  suspend fun list(): Result<List<Veranstalter>>
+  suspend fun getById(id: Long): Result<Veranstalter>
+  suspend fun create(model: Veranstalter): Result<Veranstalter>
+  suspend fun update(id: Long, model: Veranstalter): Result<Veranstalter>
+  suspend fun delete(id: Long): Result<Unit>
+}
--- a/frontend/features/veranstalter-feature/src/commonMain/kotlin/at/mocode/veranstalter/feature/presentation/VeranstalterViewModel.kt
+++ b/frontend/features/veranstalter-feature/src/commonMain/kotlin/at/mocode/veranstalter/feature/presentation/VeranstalterViewModel.kt
@ -6,6 +6,8 @@ import kotlinx.coroutines.SupervisorJob
 import kotlinx.coroutines.flow.MutableStateFlow
 import kotlinx.coroutines.flow.StateFlow
 import kotlinx.coroutines.launch
+import at.mocode.frontend.features.veranstalter.domain.VeranstalterRepository
+import at.mocode.frontend.features.veranstalter.domain.Veranstalter as DomainVeranstalter

 // UDF: State beschreibt die gesamte UI in einem Snapshot
 data class VeranstalterState(
@ -34,11 +36,6 @@ data class VeranstalterListItem(
  val loginStatus: String,
 )

-// Repository-Vertrag (später gegen echte Backend-Repositories austauschbar)
-interface VeranstalterRepository {
-  suspend fun list(): List<VeranstalterListItem>
-}
-
 class VeranstalterViewModel(
  private val repo: VeranstalterRepository,
 ) {
@ -64,14 +61,14 @@ class VeranstalterViewModel(
  private fun load() {
    reduce { it.copy(isLoading = true, errorMessage = null) }
    scope.launch {
-      try {
-        val items = repo.list()
-        // Nach dem Laden auch initial filtern
+      val result = repo.list()
+      result.onSuccess { domainList ->
+        val items = domainList.map { it.toListItem() }
        reduce { cur ->
          val filtered = filterList(items, cur.searchQuery)
          cur.copy(isLoading = false, list = items, filtered = filtered)
        }
-      } catch (t: Throwable) {
+      }.onFailure { t ->
        reduce { it.copy(isLoading = false, errorMessage = t.message ?: "Unbekannter Fehler beim Laden") }
      }
    }
@ -97,3 +94,11 @@ class VeranstalterViewModel(
    _state.value = block(_state.value)
  }
 }
+
+private fun DomainVeranstalter.toListItem() = VeranstalterListItem(
+  id = id,
+  name = name,
+  oepsNummer = oepsNummer,
+  ort = ort,
+  loginStatus = loginStatus,
+)
--- a/frontend/features/veranstalter-feature/src/jvmMain/kotlin/at/mocode/frontend/features/veranstalter/data/remote/DefaultVeranstalterRepository.kt
+++ b/frontend/features/veranstalter-feature/src/jvmMain/kotlin/at/mocode/frontend/features/veranstalter/data/remote/DefaultVeranstalterRepository.kt
@ -0,0 +1,79 @@
+package at.mocode.frontend.features.veranstalter.data.remote
+
+import at.mocode.frontend.core.network.ApiRoutes
+import at.mocode.frontend.features.veranstalter.data.mapper.toDomain
+import at.mocode.frontend.features.veranstalter.data.mapper.toDto
+import at.mocode.frontend.features.veranstalter.data.remote.dto.VeranstalterDto
+import at.mocode.frontend.features.veranstalter.domain.Veranstalter
+import at.mocode.frontend.features.veranstalter.domain.VeranstalterRepository
+import io.ktor.client.*
+import io.ktor.client.call.*
+import io.ktor.client.request.*
+import io.ktor.http.*
+
+class DefaultVeranstalterRepository(
+  private val client: HttpClient,
+) : VeranstalterRepository {
+
+  override suspend fun list(): Result<List<Veranstalter>> = runCatching {
+    val response = client.get(ApiRoutes.Veranstalter.ROOT)
+    when {
+      response.status.isSuccess() -> response.body<List<VeranstalterDto>>().map { it.toDomain() }
+      response.status == HttpStatusCode.Unauthorized -> throw AuthExpired
+      response.status == HttpStatusCode.Forbidden -> throw AuthForbidden
+      response.status.value >= 500 -> throw ServerError
+      else -> throw HttpError(response.status.value)
+    }
+  }
+
+  override suspend fun getById(id: Long): Result<Veranstalter> = runCatching {
+    val response = client.get("${ApiRoutes.Veranstalter.ROOT}/$id")
+    when {
+      response.status.isSuccess() -> response.body<VeranstalterDto>().toDomain()
+      response.status == HttpStatusCode.NotFound -> throw NotFound
+      response.status == HttpStatusCode.Unauthorized -> throw AuthExpired
+      response.status == HttpStatusCode.Forbidden -> throw AuthForbidden
+      response.status.value >= 500 -> throw ServerError
+      else -> throw HttpError(response.status.value)
+    }
+  }
+
+  override suspend fun create(model: Veranstalter): Result<Veranstalter> = runCatching {
+    val response = client.post(ApiRoutes.Veranstalter.ROOT) { setBody(model.toDto()) }
+    when {
+      response.status.isSuccess() -> response.body<VeranstalterDto>().toDomain()
+      response.status == HttpStatusCode.Conflict -> throw Conflict
+      response.status.value >= 500 -> throw ServerError
+      else -> throw HttpError(response.status.value)
+    }
+  }
+
+  override suspend fun update(id: Long, model: Veranstalter): Result<Veranstalter> = runCatching {
+    val response = client.put("${ApiRoutes.Veranstalter.ROOT}/$id") { setBody(model.toDto()) }
+    when {
+      response.status.isSuccess() -> response.body<VeranstalterDto>().toDomain()
+      response.status == HttpStatusCode.NotFound -> throw NotFound
+      response.status == HttpStatusCode.Conflict -> throw Conflict
+      response.status.value >= 500 -> throw ServerError
+      else -> throw HttpError(response.status.value)
+    }
+  }
+
+  override suspend fun delete(id: Long): Result<Unit> = runCatching {
+    val response = client.delete("${ApiRoutes.Veranstalter.ROOT}/$id")
+    when {
+      response.status.isSuccess() -> Unit
+      response.status == HttpStatusCode.NotFound -> throw NotFound
+      response.status.value >= 500 -> throw ServerError
+      else -> throw HttpError(response.status.value)
+    }
+  }
+}
+
+// Fehler-Typen (vereinfachtes DomainError-Äquivalent)
+object AuthExpired : RuntimeException("AUTH_EXPIRED")
+object AuthForbidden : RuntimeException("AUTH_FORBIDDEN")
+object NotFound : RuntimeException("NOT_FOUND")
+object Conflict : RuntimeException("CONFLICT")
+object ServerError : RuntimeException("SERVER_ERROR")
+class HttpError(val code: Int) : RuntimeException("HTTP_$code")
--- a/frontend/features/veranstalter-feature/src/jvmMain/kotlin/at/mocode/frontend/features/veranstalter/di/VeranstalterModule.kt
+++ b/frontend/features/veranstalter-feature/src/jvmMain/kotlin/at/mocode/frontend/features/veranstalter/di/VeranstalterModule.kt
@ -0,0 +1,11 @@
+package at.mocode.frontend.features.veranstalter.di
+
+import at.mocode.frontend.features.veranstalter.data.remote.DefaultVeranstalterRepository
+import at.mocode.frontend.features.veranstalter.domain.VeranstalterRepository
+import io.ktor.client.HttpClient
+import org.koin.core.qualifier.named
+import org.koin.dsl.module
+
+val veranstalterModule = module {
+  single<VeranstalterRepository> { DefaultVeranstalterRepository(get(named("apiClient"))) }
+}
--- a/frontend/features/veranstalter-feature/src/jvmMain/kotlin/at/mocode/veranstalter/feature/presentation/DefaultVeranstalterRepository.kt
+++ b/frontend/features/veranstalter-feature/src/jvmMain/kotlin/at/mocode/veranstalter/feature/presentation/DefaultVeranstalterRepository.kt
@ -1,23 +1 @@
-package at.mocode.veranstalter.feature.presentation
-
-import at.mocode.frontend.core.designsystem.models.LoginStatus
-
-class DefaultVeranstalterRepository : VeranstalterRepository {
-  override suspend fun list(): List<VeranstalterListItem> {
-    // Aus Fake-Store lesen (Prototyp)
-    return FakeVeranstalterStore.all().map { it.toListItem() }
-  }
-}
-
-private fun LoginStatus.asLabel(): String = when (this) {
-  LoginStatus.AKTIV -> "AKTIV"
-  LoginStatus.AUSSTEHEND -> "AUSSTEHEND"
-}
-
-private fun VeranstalterUiModel.toListItem() = VeranstalterListItem(
-  id = id,
-  name = name,
-  oepsNummer = oepsNummer,
-  ort = ort,
-  loginStatus = loginStatus.asLabel(),
-)
+// Deprecated fake repository removed in favor of real Ktor-backed implementation.
--- a/frontend/features/veranstalter-feature/src/jvmMain/kotlin/at/mocode/veranstalter/feature/presentation/VeranstalterAuswahlScreen.kt
+++ b/frontend/features/veranstalter-feature/src/jvmMain/kotlin/at/mocode/veranstalter/feature/presentation/VeranstalterAuswahlScreen.kt
@ -44,7 +44,8 @@ fun VeranstalterAuswahlScreen(
  onNeuerVeranstalter: () -> Unit = {},
 ) {
  // MVVM + UDF: ViewModel hält gesamten Zustand, Composable rendert nur State und sendet Intents
-  val viewModel = remember { VeranstalterViewModel(DefaultVeranstalterRepository()) }
+  val repo: at.mocode.frontend.features.veranstalter.domain.VeranstalterRepository = org.koin.compose.koinInject()
+  val viewModel = remember { VeranstalterViewModel(repo) }
  val state by viewModel.state.collectAsState()

  Column(modifier = Modifier.fillMaxSize()) {
--- a/frontend/features/veranstalter-feature/src/jvmMain/kotlin/at/mocode/veranstalter/feature/presentation/VeranstalterAuswahlV2.kt
+++ b/frontend/features/veranstalter-feature/src/jvmMain/kotlin/at/mocode/veranstalter/feature/presentation/VeranstalterAuswahlV2.kt
@ -7,6 +7,7 @@ import androidx.compose.foundation.layout.*
 import androidx.compose.foundation.lazy.LazyColumn
 import androidx.compose.foundation.lazy.items
 import androidx.compose.material.icons.Icons
+import androidx.compose.material.icons.automirrored.filled.ArrowForward
 import androidx.compose.material.icons.filled.Add
 import androidx.compose.material.icons.filled.ArrowForward
 import androidx.compose.material.icons.filled.Close
@ -175,7 +176,7 @@ fun VeranstalterAuswahlV2(
        ) {
          Text("Weiter zur Turnier-Konfiguration")
          Spacer(Modifier.width(8.dp))
-          Icon(Icons.Default.ArrowForward, null, modifier = Modifier.size(16.dp))
+          Icon(Icons.AutoMirrored.Filled.ArrowForward, null, modifier = Modifier.size(16.dp))
        }
      }
    }