feat(ErrorBanner): offline banner

androidApp/src/main/AndroidManifest.xml

@@ -3,6 +3,8 @@
 
     <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
     <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
+    <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
+    <uses-permission android:name="android.permission.INTERNET" />
 
     <application
         android:name=".MainApplication"

iosApp/iosApp.xcodeproj/project.pbxproj

@@ -15,6 +15,7 @@
 		6E04E32F2BE95A8D006F8131 /* NearbyViewModel.swift in Sources */ = {isa = PBXBuildFile; fileRef = 6E04E32E2BE95A8D006F8131 /* NearbyViewModel.swift */; };
 		6E20278E2BD989630037554F /* DummyTestAppView.swift in Sources */ = {isa = PBXBuildFile; fileRef = 6E20278D2BD989630037554F /* DummyTestAppView.swift */; };
 		6E2027902BD989AC0037554F /* ProductionAppView.swift in Sources */ = {isa = PBXBuildFile; fileRef = 6E20278F2BD989AC0037554F /* ProductionAppView.swift */; };
+		6E2D6CA12CC2EDD700959605 /* ErrorBannerViewModelTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = 6E2D6CA02CC2EDD700959605 /* ErrorBannerViewModelTests.swift */; };
 		6E35D4CE2B72C74500A2BF95 /* MapboxMaps in Frameworks */ = {isa = PBXBuildFile; productRef = 6E35D4CD2B72C74500A2BF95 /* MapboxMaps */; };
 		6E35D4D02B72C7B700A2BF95 /* HomeMapView.swift in Sources */ = {isa = PBXBuildFile; fileRef = 6E35D4CF2B72C7B700A2BF95 /* HomeMapView.swift */; };
 		6E35D4D32B72CD3900A2BF95 /* HomeMapViewTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = 6E35D4D22B72CD3900A2BF95 /* HomeMapViewTests.swift */; };
@@ -249,6 +250,7 @@
 		6E04E32E2BE95A8D006F8131 /* NearbyViewModel.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = NearbyViewModel.swift; sourceTree = "<group>"; };
 		6E20278D2BD989630037554F /* DummyTestAppView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = DummyTestAppView.swift; sourceTree = "<group>"; };
 		6E20278F2BD989AC0037554F /* ProductionAppView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ProductionAppView.swift; sourceTree = "<group>"; };
+		6E2D6CA02CC2EDD700959605 /* ErrorBannerViewModelTests.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ErrorBannerViewModelTests.swift; sourceTree = "<group>"; };
 		6E35D4CF2B72C7B700A2BF95 /* HomeMapView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = HomeMapView.swift; sourceTree = "<group>"; };
 		6E35D4D22B72CD3900A2BF95 /* HomeMapViewTests.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = HomeMapViewTests.swift; sourceTree = "<group>"; };
 		6E3C8D7D2C11FDA80059C28C /* ActionButton.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ActionButton.swift; sourceTree = "<group>"; };
@@ -594,6 +596,7 @@
 			isa = PBXGroup;
 			children = (
 				6EFEE42A2BEC100100810319 /* NearbyViewModelTests.swift */,
+				6E2D6CA02CC2EDD700959605 /* ErrorBannerViewModelTests.swift */,
 			);
 			path = ViewModels;
 			sourceTree = "<group>";
@@ -1292,6 +1295,7 @@
 				8C5F47662C40842200FB71DA /* TripDetailsStopViewTests.swift in Sources */,
 				8CDF2C342BE9357E007FC912 /* OptionalNavigationLinkTests.swift in Sources */,
 				8CA1FB772BF813F500384658 /* TripDetailsStopListSplitViewTests.swift in Sources */,
+				6E2D6CA12CC2EDD700959605 /* ErrorBannerViewModelTests.swift in Sources */,
 				8CB823DB2BC5F053002C87E0 /* StopDetailsRoutesViewTests.swift in Sources */,
 				6E4EACFC2B7A82AC0011AB8B /* MockLocationFetcher.swift in Sources */,
 				8CE36C932CADEDD300D77F22 /* FetchApiTests.swift in Sources */,

iosApp/iosApp/ComponentViews/ErrorBanner.swift

@@ -46,6 +46,12 @@ struct ErrorBanner: View {
                 }
                 .frame(minHeight: minHeight)
             }
+        case .networkError:
+            ErrorCard { HStack {
+                Image(systemName: "wifi.slash")
+                Text("Unable to connect")
+                Spacer()
+            }}
         case nil:
             // for some reason, .collect on an EmptyView doesn't work
             EmptyView()

iosApp/iosApp/ComponentViews/ErrorCard.swift

@@ -8,16 +8,16 @@
 
 import SwiftUI
 
-struct ErrorCard: View {
-    var details: Text
+struct ErrorCard<Content: View>: View {
+    @ViewBuilder let details: Content
     var button: (() -> AnyView)?
 
-    init(_ details: () -> Text) {
+    init(_ details: () -> Content) {
         self.details = details()
         button = nil
     }
 
-    init(details: Text, button: (() -> AnyView)? = nil) {
+    init(details: Content, button: (() -> AnyView)? = nil) {
         self.details = details
         self.button = button
     }

iosApp/iosApp/Localizable.xcstrings

@@ -441,6 +441,9 @@
     },
     "trains" : {
       "comment" : "trains"
+    },
+    "Unable to connect" : {
+
     },
     "Unruly Passenger" : {
       "comment" : "Possible alert cause"

iosApp/iosApp/ViewModels/ErrorBannerViewModel.swift

@@ -13,24 +13,33 @@
     let errorRepository: IErrorBannerStateRepository
 
     @Published
     private(set) var errorState: ErrorBannerState? = nil
 
     @Published
     var loadingWhenPredictionsStale: Bool
 
+    // option for testing
+    var skipListeningForStateChanges = false
+
     init(
         errorRepository: IErrorBannerStateRepository = RepositoryDI().errorBanner,
-        initialLoadingWhenPredictionsStale: Bool = false
+        initialLoadingWhenPredictionsStale: Bool = false,
+        skipListeningForStateChanges: Bool = false
     ) {
         self.errorRepository = errorRepository
         loadingWhenPredictionsStale = initialLoadingWhenPredictionsStale
         errorState = self.errorRepository.state.value
+        self.skipListeningForStateChanges = skipListeningForStateChanges
     }
 
     @MainActor
     func activate() async {
-        for await errorState in errorRepository.state {
-            self.errorState = errorState
+        errorRepository.subscribeToNetworkStatusChanges()
+
+        if !skipListeningForStateChanges {
+            for await errorState in errorRepository.state {
+                self.errorState = errorState
+            }
         }
     }
 

iosApp/iosAppTests/Utils/FetchApiTests.swift

@@ -54,7 +54,12 @@ final class FetchApiTests: XCTestCase {
             onRefreshAfterError: { expRefresh.fulfill() }
         )
         XCTAssertNotNil(errorBannerRepo.state.value)
-        errorBannerRepo.state.value?.action()
+
+        if let action = errorBannerRepo.state.value?.action {
+            action()
+        } else {
+            XCTFail("data error missing action")
+        }
         await fulfillment(of: [expRefresh], timeout: 1)
     }
 

iosApp/iosAppTests/ViewModels/ErrorBannerViewModelTests.swift

@@ -0,0 +1,26 @@
+//
+//  ErrorBannerViewModelTests.swift
+//  iosAppTests
+//
+//  Created by Kayla Brady on 10/18/24.
+//  Copyright © 2024 MBTA. All rights reserved.
+//
+
+import Foundation
+@testable import iosApp
+import shared
+import XCTest
+
+final class ErrorBannerViewModelTests: XCTestCase {
+    func testActivateSubscribesToNetworkChanges() async {
+        let onSubscribeExp = XCTestExpectation(description: "onSubscribe called")
+        let repo = MockErrorBannerStateRepository(state: nil, onSubscribeToNetworkChanges: { onSubscribeExp.fulfill() })
+        let errorVM = ErrorBannerViewModel(
+            errorRepository: repo,
+            initialLoadingWhenPredictionsStale: false,
+            skipListeningForStateChanges: true
+        )
+        await errorVM.activate()
+        wait(for: [onSubscribeExp], timeout: 1)
+    }
+}

iosApp/iosAppTests/Views/ErrorBannerTests.swift

@@ -49,6 +49,14 @@ final class ErrorBannerTests: XCTestCase {
         wait(for: [callsAction], timeout: 1)
     }
 
+    @MainActor func testWhenNetworkError() throws {
+        let sut = ErrorBanner(.init(
+            errorRepository: MockErrorBannerStateRepository(state: .NetworkError()),
+            initialLoadingWhenPredictionsStale: true
+        ))
+        XCTAssertNotNil(try sut.inspect().find(text: "Unable to connect"))
+    }
+
     @MainActor func testLoadingWhenPredictionsStale() throws {
         let sut = ErrorBanner(.init(
             errorRepository: MockErrorBannerStateRepository(state: .StalePredictions(

shared/src/androidMain/kotlin/com/mbta/tid/mbta_app/PlatformModule.kt

@@ -1,12 +1,15 @@
 package com.mbta.tid.mbta_app
 
+import com.mbta.tid.mbta_app.network.INetworkConnectivityMonitor
+import com.mbta.tid.mbta_app.network.NetworkConnectivityMonitor
 import com.mbta.tid.mbta_app.utils.AndroidSystemPaths
 import com.mbta.tid.mbta_app.utils.SystemPaths
 import org.koin.dsl.module
 
 fun platformModule() = module {
     includes(
         module { single { createDataStore(get()) } },
-        module { single<SystemPaths> { AndroidSystemPaths(get()) } }
+        module { single<SystemPaths> { AndroidSystemPaths(get()) } },
+        module { single<INetworkConnectivityMonitor> { NetworkConnectivityMonitor(get()) } }
     )
 }

shared/src/androidMain/kotlin/com/mbta/tid/mbta_app/network/NetworkConnectivityMonitor.kt

@@ -0,0 +1,33 @@
+package com.mbta.tid.mbta_app.network
+
+import android.annotation.SuppressLint
+import android.content.Context
+import android.content.Context.CONNECTIVITY_SERVICE
+import android.net.ConnectivityManager
+import android.net.Network
+
+class NetworkConnectivityMonitor(context: Context) : INetworkConnectivityMonitor {
+    private var networkCallback: ConnectivityManager.NetworkCallback? = null
+    private val connectivityManager =
+        context.getSystemService(CONNECTIVITY_SERVICE) as ConnectivityManager
+
+    @SuppressLint("MissingPermission")
+    // Permission is included in AndroidManifest.xml
+    override fun registerListener(onNetworkAvailable: () -> Unit, onNetworkLost: () -> Unit) {
+        networkCallback =
+            object : ConnectivityManager.NetworkCallback() {
+                override fun onAvailable(network: Network) {
+                    onNetworkAvailable()
+                }
+
+                override fun onUnavailable() {
+                    onNetworkLost()
+                }
+
+                override fun onLost(network: Network) {
+                    onNetworkLost()
+                }
+            }
+        networkCallback?.let { connectivityManager.registerDefaultNetworkCallback(it) }
+    }
+}

shared/src/commonMain/kotlin/com/mbta/tid/mbta_app/dependencyInjection/RepositoryDI.kt

@@ -93,6 +93,7 @@ class RepositoryDI : IRepositories, KoinComponent {
 class RealRepositories : IRepositories {
     // initialize repositories with platform-specific dependencies as null.
     // instantiate the real repositories in makeNativeModule
+
     override val alerts = null
     override val appCheck = null
     override val config = ConfigRepository()

shared/src/commonMain/kotlin/com/mbta/tid/mbta_app/model/ErrorBannerState.kt

@@ -5,12 +5,14 @@ import kotlinx.datetime.Instant
 
 sealed class ErrorBannerState {
     /** What to do when the button in the error banner is pressed */
-    abstract val action: () -> Unit
+    abstract val action: (() -> Unit)?
 
     data class StalePredictions(val lastUpdated: Instant, override val action: () -> Unit) :
         ErrorBannerState() {
         fun minutesAgo() = (Clock.System.now() - lastUpdated).inWholeMinutes
     }
 
     data class DataError(override val action: () -> Unit) : ErrorBannerState()
+
+    data class NetworkError(override val action: (() -> Unit)?) : ErrorBannerState()
 }

shared/src/commonMain/kotlin/com/mbta/tid/mbta_app/network/NetworkConnectivityMonitor.kt

@@ -0,0 +1,6 @@
+package com.mbta.tid.mbta_app.network
+
+/** Observe changes in the device's network connectivity. */
+interface INetworkConnectivityMonitor {
+    fun registerListener(onNetworkAvailable: () -> Unit, onNetworkLost: () -> Unit)
+}

shared/src/commonMain/kotlin/com/mbta/tid/mbta_app/repositories/ErrorBannerStateRepository.kt

@@ -1,24 +1,47 @@
 package com.mbta.tid.mbta_app.repositories
 
 import com.mbta.tid.mbta_app.model.ErrorBannerState
+import com.mbta.tid.mbta_app.network.INetworkConnectivityMonitor
 import kotlin.time.Duration.Companion.minutes
 import kotlinx.coroutines.flow.MutableStateFlow
 import kotlinx.coroutines.flow.asStateFlow
 import kotlinx.datetime.Clock
 import kotlinx.datetime.Instant
 import org.koin.core.component.KoinComponent
+import org.koin.core.component.inject
+
+sealed class NetworkStatus {
+    data object Connected : NetworkStatus()
+
+    data object Disconnected : NetworkStatus()
+}
+
+abstract class IErrorBannerStateRepository(initialState: ErrorBannerState? = null) : KoinComponent {
+
+    private val networkConnectivityMonitor: INetworkConnectivityMonitor by inject()
+
+    /*
+    Registers platform-specific observer of network status changes.
+     */
+    open fun subscribeToNetworkStatusChanges() {
+        this.networkConnectivityMonitor.registerListener(
+            onNetworkAvailable = { setNetworkStatus(NetworkStatus.Connected) },
+            onNetworkLost = { setNetworkStatus(NetworkStatus.Disconnected) }
+        )
+    }
 
-abstract class IErrorBannerStateRepository
-protected constructor(initialState: ErrorBannerState? = null) {
     protected val flow = MutableStateFlow(initialState)
     val state = flow.asStateFlow()
 
+    private var networkStatus: NetworkStatus? = null
+
     private var predictionsStale: ErrorBannerState.StalePredictions? = null
     private val dataErrors = mutableMapOf<String, ErrorBannerState.DataError>()
 
     protected open fun updateState() {
         flow.value =
             when {
+                networkStatus == NetworkStatus.Disconnected -> ErrorBannerState.NetworkError(null)
                 dataErrors.isNotEmpty() ->
                     // encapsulate all the different error actions within one error
                     ErrorBannerState.DataError { dataErrors.values.forEach { it.action() } }
@@ -41,6 +64,11 @@ protected constructor(initialState: ErrorBannerState? = null) {
         updateState()
     }
 
+    private fun setNetworkStatus(newStatus: NetworkStatus) {
+        networkStatus = newStatus
+        updateState()
+    }
+
     fun setDataError(key: String, action: () -> Unit) {
         dataErrors[key] = ErrorBannerState.DataError(action)
         updateState()
@@ -60,8 +88,15 @@ protected constructor(initialState: ErrorBannerState? = null) {
 
 class ErrorBannerStateRepository : IErrorBannerStateRepository(), KoinComponent
 
-class MockErrorBannerStateRepository(state: ErrorBannerState? = null) :
-    IErrorBannerStateRepository(state) {
+class MockErrorBannerStateRepository(
+    state: ErrorBannerState? = null,
+    onSubscribeToNetworkChanges: (() -> Unit)? = null
+) : IErrorBannerStateRepository(state) {
+    private val onSubscribeToNetworkChanges = onSubscribeToNetworkChanges
     val mutableFlow
         get() = flow
+
+    override fun subscribeToNetworkStatusChanges() {
+        onSubscribeToNetworkChanges?.invoke()
+    }
 }

shared/src/commonTest/kotlin/com/mbta/tid/mbta_app/repositories/ErrorBannerStateRepositoryTest.kt

@@ -1,6 +1,12 @@
 package com.mbta.tid.mbta_app.repositories
 
 import com.mbta.tid.mbta_app.model.ErrorBannerState
+import com.mbta.tid.mbta_app.network.INetworkConnectivityMonitor
+import dev.mokkery.MockMode
+import dev.mokkery.matcher.any
+import dev.mokkery.mock
+import dev.mokkery.verify
+import kotlin.test.AfterTest
 import kotlin.test.Test
 import kotlin.test.assertEquals
 import kotlin.test.assertIs
@@ -13,8 +19,13 @@ import kotlinx.coroutines.flow.take
 import kotlinx.coroutines.launch
 import kotlinx.coroutines.runBlocking
 import kotlinx.datetime.Clock
+import org.koin.core.context.startKoin
+import org.koin.core.context.stopKoin
+import org.koin.dsl.module
 
 class ErrorBannerStateRepositoryTest {
+    @AfterTest fun `stop koin`() = run { stopKoin() }
+
     @Test
     fun `initial state is null`() = runBlocking {
         val repo = ErrorBannerStateRepository()
@@ -112,4 +123,18 @@ class ErrorBannerStateRepositoryTest {
 
         assertNull(channel.receive())
     }
+
+    @Test
+    fun `subscribe to connectivity changes`() {
+
+        val mockNetworkMonitor = mock<INetworkConnectivityMonitor>(MockMode.autofill)
+
+        startKoin { modules(module { single<INetworkConnectivityMonitor> { mockNetworkMonitor } }) }
+
+        val repo = ErrorBannerStateRepository()
+
+        repo.subscribeToNetworkStatusChanges()
+
+        verify { mockNetworkMonitor.registerListener(any(), any()) }
+    }
 }

shared/src/iosMain/kotlin/com/mbta/tid/mbta_app/PlatformModule.kt

@@ -1,12 +1,15 @@
 package com.mbta.tid.mbta_app
 
+import com.mbta.tid.mbta_app.network.INetworkConnectivityMonitor
+import com.mbta.tid.mbta_app.network.NetworkConnectivityMonitor
 import com.mbta.tid.mbta_app.utils.IOSSystemPaths
 import com.mbta.tid.mbta_app.utils.SystemPaths
 import org.koin.dsl.module
 
 fun platformModule() = module {
     includes(
         module { single { createDataStore() } },
-        module { single<SystemPaths> { IOSSystemPaths() } }
+        module { single<SystemPaths> { IOSSystemPaths() } },
+        module { single<INetworkConnectivityMonitor> { NetworkConnectivityMonitor() } }
     )
 }