Part 3: Rust SyncManager integration

Co-authored-by: Arturo Mejia <arturomejiamarmol@gmail.com>

buildSrc/src/main/java/Dependencies.kt

@@ -122,6 +122,7 @@ object Dependencies {
 
     const val mozilla_sync_logins = "org.mozilla.appservices:logins:${Versions.mozilla_appservices}"
     const val mozilla_places = "org.mozilla.appservices:places:${Versions.mozilla_appservices}"
+    const val mozilla_sync_manager = "org.mozilla.appservices:syncmanager:${Versions.mozilla_appservices}"
 
     const val mozilla_push = "org.mozilla.appservices:push:${Versions.mozilla_appservices}"
 

components/browser/storage-sync/build.gradle

@@ -63,7 +63,6 @@ dependencies {
 
     testImplementation Dependencies.mozilla_places
     testImplementation Dependencies.testing_mockwebserver
-    testImplementation Dependencies.androidx_work_testing
 
     testImplementation Dependencies.mozilla_full_megazord_forUnitTests
 }

components/browser/storage-sync/src/main/java/mozilla/components/browser/storage/sync/Connection.kt

@@ -25,6 +25,13 @@ const val DB_NAME = "places.sqlite"
  * Writer is always the same, as guaranteed by [PlacesApi].
  */
 internal interface Connection : Closeable {
+    /**
+     * This should be removed. See: https://github.com/mozilla/application-services/issues/1877
+     *
+     * @return raw internal handle that could be used for referencing underlying [PlacesApi]. Use it with SyncManager.
+     */
+    fun getHandle(): Long
+
     fun reader(): PlacesReaderConnection
     fun writer(): PlacesWriterConnection
 
@@ -57,6 +64,11 @@ internal object RustPlacesConnection : Connection {
         cachedReader = api!!.openReader()
     }
 
+    override fun getHandle(): Long {
+        check(api != null) { "must call init first" }
+        return api!!.getHandle()
+    }
+
     override fun reader(): PlacesReaderConnection = synchronized(this) {
         check(cachedReader != null) { "must call init first" }
         return cachedReader!!

components/browser/storage-sync/src/main/java/mozilla/components/browser/storage/sync/PlacesBookmarksStorage.kt

@@ -184,4 +184,13 @@ open class PlacesBookmarksStorage(context: Context) : PlacesStorage(context), Bo
             }
         }
     }
+
+    /**
+     * This should be removed. See: https://github.com/mozilla/application-services/issues/1877
+     *
+     * @return raw internal handle that could be used for referencing underlying [PlacesApi]. Use it with SyncManager.
+     */
+    override fun getHandle(): Long {
+        return places.getHandle()
+    }
 }

components/browser/storage-sync/src/main/java/mozilla/components/browser/storage/sync/PlacesHistoryStorage.kt

@@ -6,6 +6,7 @@ package mozilla.components.browser.storage.sync
 
 import android.content.Context
 import kotlinx.coroutines.withContext
+import mozilla.appservices.places.PlacesApi
 import mozilla.appservices.places.VisitObservation
 import mozilla.components.concept.storage.HistoryAutocompleteResult
 import mozilla.components.concept.storage.HistoryStorage
@@ -177,4 +178,13 @@ open class PlacesHistoryStorage(context: Context) : PlacesStorage(context), Hist
             }
         }
     }
+
+    /**
+     * This should be removed. See: https://github.com/mozilla/application-services/issues/1877
+     *
+     * @return raw internal handle that could be used for referencing underlying [PlacesApi]. Use it with SyncManager.
+     */
+    override fun getHandle(): Long {
+        return places.getHandle()
+    }
 }

components/browser/storage-sync/src/test/java/mozilla/components/browser/storage/sync/PlacesHistoryStorageTest.kt

@@ -501,6 +501,11 @@ class PlacesHistoryStorageTest {
                 fail()
             }
 
+            override fun getHandle(): Long {
+                fail()
+                return 0L
+            }
+
             override fun close() {
                 fail()
             }
@@ -533,6 +538,11 @@ class PlacesHistoryStorageTest {
 
             override fun syncBookmarks(syncInfo: SyncAuthInfo) {}
 
+            override fun getHandle(): Long {
+                fail()
+                return 0L
+            }
+
             override fun close() {
                 fail()
             }
@@ -565,6 +575,11 @@ class PlacesHistoryStorageTest {
                 fail()
             }
 
+            override fun getHandle(): Long {
+                fail()
+                return 0L
+            }
+
             override fun close() {
                 fail()
             }
@@ -601,6 +616,11 @@ class PlacesHistoryStorageTest {
                 fail()
             }
 
+            override fun getHandle(): Long {
+                fail()
+                return 0L
+            }
+
             override fun close() {
                 fail()
             }

components/concept/sync/src/main/java/mozilla/components/concept/sync/Devices.kt

@@ -4,6 +4,7 @@
 @file:SuppressWarnings("TooManyFunctions")
 package mozilla.components.concept.sync
 
+import android.content.Context
 import androidx.lifecycle.LifecycleOwner
 import kotlinx.coroutines.Deferred
 import mozilla.components.support.base.observer.Observable
@@ -51,9 +52,10 @@ interface DeviceConstellation : Observable<DeviceEventsObserver> {
     /**
      * Set name of the current device.
      * @param name New device name.
+     * @param context An application context, used for updating internal caches.
      * @return A [Deferred] that will be resolved with a success flag once operation is complete.
      */
-    fun setDeviceNameAsync(name: String): Deferred<Boolean>
+    fun setDeviceNameAsync(name: String, context: Context): Deferred<Boolean>
 
     /**
      * Set a [DevicePushSubscription] for the current device.

components/concept/sync/src/main/java/mozilla/components/concept/sync/Sync.kt

@@ -53,6 +53,13 @@ interface SyncableStore {
      * @return [SyncStatus] A status object describing how sync went.
      */
     suspend fun sync(authInfo: SyncAuthInfo): SyncStatus
+
+    /**
+     * This should be removed. See: https://github.com/mozilla/application-services/issues/1877
+     *
+     * @return raw internal handle that could be used for referencing underlying [PlacesApi]. Use it with SyncManager.
+     */
+    fun getHandle(): Long
 }
 
 /**

components/feature/accounts/src/main/java/mozilla/components/feature/accounts/FxaWebChannelFeature.kt

@@ -17,6 +17,7 @@ import mozilla.components.concept.sync.AuthType
 import mozilla.components.service.fxa.FxaAuthData
 import mozilla.components.service.fxa.SyncEngine
 import mozilla.components.service.fxa.manager.FxaAccountManager
+import mozilla.components.service.fxa.sync.toSyncEngines
 import mozilla.components.service.fxa.toAuthType
 import mozilla.components.support.base.feature.LifecycleAwareFeature
 import mozilla.components.support.base.log.logger.Logger
@@ -248,6 +249,14 @@ class FxaWebChannelFeature(
             return status
         }
 
+        private fun JSONArray.toStringList(): List<String> {
+            val result = mutableListOf<String>()
+            for (i in 0 until this.length()) {
+                this.optString(i, null)?.let { result.add(it) }
+            }
+            return result
+        }
+
         /**
          * Handles the [COMMAND_OAUTH_LOGIN] event from the web-channel.
          */
@@ -255,12 +264,14 @@ class FxaWebChannelFeature(
             val authType: AuthType
             val code: String
             val state: String
+            val declinedEngines: List<String>?
 
             try {
                 val data = payload.getJSONObject("data")
                 authType = data.getString("action").toAuthType()
                 code = data.getString("code")
                 state = data.getString("state")
+                declinedEngines = data.optJSONArray("declinedSyncEngines")?.toStringList()
             } catch (e: JSONException) {
                 // TODO ideally, this should log to Sentry.
                 logger.error("Error while processing WebChannel oauth-login command", e)
@@ -270,7 +281,8 @@ class FxaWebChannelFeature(
             accountManager.finishAuthenticationAsync(FxaAuthData(
                 authType = authType,
                 code = code,
-                state = state
+                state = state,
+                declinedEngines = declinedEngines?.toSyncEngines()
             ))
 
             return null

components/feature/accounts/src/test/java/mozilla/components/feature/accounts/FxaWebChannelFeatureTest.kt

@@ -159,7 +159,7 @@ class FxaWebChannelFeatureTest {
         val messageHandler = argumentCaptor<MessageHandler>()
         val responseToTheWebChannel = argumentCaptor<JSONObject>()
         val port = mock<Port>()
-        val expectedEngines = setOf(SyncEngine.HISTORY)
+        val expectedEngines = setOf(SyncEngine.History)
 
         WebExtensionController.installedExtensions[FxaWebChannelFeature.WEB_CHANNEL_EXTENSION_ID] = ext
 
@@ -201,7 +201,7 @@ class FxaWebChannelFeatureTest {
         val messageHandler = argumentCaptor<MessageHandler>()
         val responseToTheWebChannel = argumentCaptor<JSONObject>()
         val port = mock<Port>()
-        val expectedEngines = setOf(SyncEngine.HISTORY)
+        val expectedEngines = setOf(SyncEngine.History)
 
         WebExtensionController.installedExtensions[FxaWebChannelFeature.WEB_CHANNEL_EXTENSION_ID] = ext
 
@@ -250,7 +250,7 @@ class FxaWebChannelFeatureTest {
         val messageHandler = argumentCaptor<MessageHandler>()
         val responseToTheWebChannel = argumentCaptor<JSONObject>()
         val port = mock<Port>()
-        val expectedEngines = setOf(SyncEngine.HISTORY, SyncEngine.BOOKMARKS, SyncEngine.PASSWORDS)
+        val expectedEngines = setOf(SyncEngine.History, SyncEngine.Bookmarks, SyncEngine.Passwords)
 
         WebExtensionController.installedExtensions[FxaWebChannelFeature.WEB_CHANNEL_EXTENSION_ID] = ext
 
@@ -301,7 +301,7 @@ class FxaWebChannelFeatureTest {
         val messageHandler = argumentCaptor<MessageHandler>()
         val responseToTheWebChannel = argumentCaptor<JSONObject>()
         val port = mock<Port>()
-        val expectedEngines = setOf(SyncEngine.HISTORY, SyncEngine.BOOKMARKS, SyncEngine.PASSWORDS)
+        val expectedEngines = setOf(SyncEngine.History, SyncEngine.Bookmarks, SyncEngine.Passwords)
         val logoutDeferred = CompletableDeferred<Unit>()
 
         WebExtensionController.installedExtensions[FxaWebChannelFeature.WEB_CHANNEL_EXTENSION_ID] = ext
@@ -363,7 +363,7 @@ class FxaWebChannelFeatureTest {
         val messageHandler = argumentCaptor<MessageHandler>()
         val responseToTheWebChannel = argumentCaptor<JSONObject>()
         val port = mock<Port>()
-        val expectedEngines = setOf(SyncEngine.HISTORY, SyncEngine.BOOKMARKS, SyncEngine.PASSWORDS)
+        val expectedEngines = setOf(SyncEngine.History, SyncEngine.Bookmarks, SyncEngine.Passwords)
         val logoutDeferred = CompletableDeferred<Unit>()
 
         WebExtensionController.installedExtensions[FxaWebChannelFeature.WEB_CHANNEL_EXTENSION_ID] = ext
@@ -425,7 +425,7 @@ class FxaWebChannelFeatureTest {
         val messageHandler = argumentCaptor<MessageHandler>()
         val responseToTheWebChannel = argumentCaptor<JSONObject>()
         val port = mock<Port>()
-        val expectedEngines = setOf(SyncEngine.HISTORY, SyncEngine.BOOKMARKS, SyncEngine.PASSWORDS)
+        val expectedEngines = setOf(SyncEngine.History, SyncEngine.Bookmarks, SyncEngine.Passwords)
 
         WebExtensionController.installedExtensions[FxaWebChannelFeature.WEB_CHANNEL_EXTENSION_ID] = ext
 
@@ -477,7 +477,7 @@ class FxaWebChannelFeatureTest {
         val messageHandler = argumentCaptor<MessageHandler>()
         val responseToTheWebChannel = argumentCaptor<JSONObject>()
         val port = mock<Port>()
-        val expectedEngines = setOf(SyncEngine.HISTORY, SyncEngine.BOOKMARKS, SyncEngine.PASSWORDS)
+        val expectedEngines = setOf(SyncEngine.History, SyncEngine.Bookmarks, SyncEngine.Passwords)
 
         WebExtensionController.installedExtensions[FxaWebChannelFeature.WEB_CHANNEL_EXTENSION_ID] = ext
 
@@ -591,13 +591,13 @@ class FxaWebChannelFeatureTest {
         messageHandler.value.onPortConnected(port)
 
         // Action: signin
-        verifyOauthLogin("signin", AuthType.Signin, "fffs", "fsdf32", messageHandler.value, accountManager)
+        verifyOauthLogin("signin", AuthType.Signin, "fffs", "fsdf32", null, messageHandler.value, accountManager)
         // Signup.
-        verifyOauthLogin("signup", AuthType.Signup, "anotherCode1", "anotherState2", messageHandler.value, accountManager)
+        verifyOauthLogin("signup", AuthType.Signup, "anotherCode1", "anotherState2", setOf(SyncEngine.Passwords), messageHandler.value, accountManager)
         // Pairing.
-        verifyOauthLogin("pairing", AuthType.Pairing, "anotherCode2", "anotherState3", messageHandler.value, accountManager)
+        verifyOauthLogin("pairing", AuthType.Pairing, "anotherCode2", "anotherState3", null, messageHandler.value, accountManager)
         // Some other action.
-        verifyOauthLogin("newAction", AuthType.OtherExternal("newAction"), "anotherCode3", "anotherState4", messageHandler.value, accountManager)
+        verifyOauthLogin("newAction", AuthType.OtherExternal("newAction"), "anotherCode3", "anotherState4", null, messageHandler.value, accountManager)
     }
 
     // Receiving an oauth-login message account manager refuses the request
@@ -628,13 +628,13 @@ class FxaWebChannelFeatureTest {
         messageHandler.value.onPortConnected(port)
 
         // Action: signin
-        verifyOauthLogin("signin", AuthType.Signin, "fffs", "fsdf32", messageHandler.value, accountManager)
+        verifyOauthLogin("signin", AuthType.Signin, "fffs", "fsdf32", setOf(SyncEngine.Passwords, SyncEngine.Bookmarks), messageHandler.value, accountManager)
         // Signup.
-        verifyOauthLogin("signup", AuthType.Signup, "anotherCode1", "anotherState2", messageHandler.value, accountManager)
+        verifyOauthLogin("signup", AuthType.Signup, "anotherCode1", "anotherState2", null, messageHandler.value, accountManager)
         // Pairing.
-        verifyOauthLogin("pairing", AuthType.Pairing, "anotherCode2", "anotherState3", messageHandler.value, accountManager)
+        verifyOauthLogin("pairing", AuthType.Pairing, "anotherCode2", "anotherState3", null, messageHandler.value, accountManager)
         // Some other action.
-        verifyOauthLogin("newAction", AuthType.OtherExternal("newAction"), "anotherCode3", "anotherState4", messageHandler.value, accountManager)
+        verifyOauthLogin("newAction", AuthType.OtherExternal("newAction"), "anotherCode3", "anotherState4", null, messageHandler.value, accountManager)
     }
 
     // Receiving can-link-account  returns 'ok=true' message (for now)
@@ -648,7 +648,7 @@ class FxaWebChannelFeatureTest {
         val messageHandler = argumentCaptor<MessageHandler>()
         val jsonFromWebChannel = argumentCaptor<JSONObject>()
         val port = mock<Port>()
-        val expectedEngines = setOf(SyncEngine.HISTORY, SyncEngine.BOOKMARKS)
+        val expectedEngines = setOf(SyncEngine.History, SyncEngine.Bookmarks)
 
         WebExtensionController.installedExtensions[FxaWebChannelFeature.WEB_CHANNEL_EXTENSION_ID] = ext
 
@@ -768,19 +768,20 @@ class FxaWebChannelFeatureTest {
             .getBoolean("ok")
     }
 
-    private fun verifyOauthLogin(action: String, expectedAuthType: AuthType, code: String, state: String, messageHandler: MessageHandler, accountManager: FxaAccountManager) {
-        val jsonToWebChannel = jsonOauthLogin(action, code, state)
+    private fun verifyOauthLogin(action: String, expectedAuthType: AuthType, code: String, state: String, declined: Set<SyncEngine>?, messageHandler: MessageHandler, accountManager: FxaAccountManager) {
+        val jsonToWebChannel = jsonOauthLogin(action, code, state, declined ?: emptySet())
         messageHandler.onPortMessage(jsonToWebChannel, mock())
 
         val expectedAuthData = FxaAuthData(
             authType = expectedAuthType,
             code = code,
-            state = state
+            state = state,
+            declinedEngines = declined ?: emptySet()
         )
         verify(accountManager).finishAuthenticationAsync(expectedAuthData)
     }
 
-    private fun jsonOauthLogin(action: String, code: String, state: String): JSONObject {
+    private fun jsonOauthLogin(action: String, code: String, state: String, declined: Set<SyncEngine>): JSONObject {
         return JSONObject(
             """{
              "message":{
@@ -790,7 +791,8 @@ class FxaWebChannelFeatureTest {
                     "action":"$action",
                     "redirect":"urn:ietf:wg:oauth:2.0:oob:oauth-redirect-webchannel",
                     "code":"$code",
-                    "state":"$state"
+                    "state":"$state",
+                    "declinedSyncEngines":${declined.map { "${it.nativeName}," }.filterNotNull()}
                 }
              }
             }""".trimIndent()

components/service/firefox-accounts/README.md

@@ -26,6 +26,11 @@ Useful companion components:
 * [feature-accounts](https://github.com/mozilla-mobile/android-components/tree/master/components/feature/accounts), provides a `tabs` integration on top of `FxaAccountManager`, to handle display of web sign-in UI.
 * [browser-storage-sync](https://github.com/mozilla-mobile/android-components/tree/master/components/browser/storage-sync), provides data storage layers compatible with Firefox Sync.
 
+## Before using this component
+Products sending telemetry and using this component *must request* a data-review following [this process](https://wiki.mozilla.org/Firefox/Data_Collection).
+This component provides data collection using the [Glean SDK](https://mozilla.github.io/glean/book/index.html).
+The list of metrics being collected is available in the [metrics documentation](../../support/sync-telemetry/docs/metrics.md).
+
 ## Usage
 ### Setting up the dependency
 
@@ -42,8 +47,8 @@ Additionally, see `feature-accounts`
 
 ```kotlin
 // Make the two "syncable" stores accessible to account manager's sync machinery.
-GlobalSyncableStoreProvider.configureStore("history" to historyStorage)
-GlobalSyncableStoreProvider.configureStore("bookmarks" to bookmarksStorage)
+GlobalSyncableStoreProvider.configureStore(SyncEngine.History to historyStorage)
+GlobalSyncableStoreProvider.configureStore(SyncEngine.Bookmarks to bookmarksStorage)
 
 val accountManager = FxaAccountManager(
     context = this,
@@ -53,7 +58,7 @@ val accountManager = FxaAccountManager(
         type = DeviceType.MOBILE,
         capabilities = setOf(DeviceCapability.SEND_TAB)
     ),
-    syncConfig = SyncConfig(setOf("history", "bookmarks"), syncPeriodInMinutes = 15L)
+    syncConfig = SyncConfig(setOf(SyncEngine.History, SyncEngine.Bookmarks), syncPeriodInMinutes = 15L)
 )
 
 // Observe changes to the account and profile.
@@ -75,7 +80,7 @@ launch { accountManager.initAsync().await() }
 
 // 'Sync Now' button binding.
 findViewById<View>(R.id.buttonSync).setOnClickListener {
-    accountManager.syncNowAsync()
+    accountManager.syncNowAsync(SyncReason.User)
 }
 
 // 'Sign-in' button binding.
@@ -97,7 +102,7 @@ findViewById<View>(R.id.buttonLogout).setOnClickListener {
 findViewById<View>(R.id.disablePeriodicSync).setOnClickListener {
     launch {
         accountManager.setSyncConfigAsync(
-            SyncConfig(setOf("history", "bookmarks")
+            SyncConfig(setOf(SyncReason.History, SyncReason.Bookmarks)
         ).await()
     }
 }
@@ -106,11 +111,20 @@ findViewById<View>(R.id.disablePeriodicSync).setOnClickListener {
 findViewById<View>(R.id.enablePeriodicSync).setOnClickListener {
     launch {
         accountManager.setSyncConfigAsync(
-            SyncConfig(setOf("history", "bookmarks"), syncPeriodInMinutes = 60L)
+            SyncConfig(setOf(SyncReason.History, SyncReason.Bookmarks), syncPeriodInMinutes = 60L)
         ).await()
     }
 }
 
+// Globally disabled syncing an engine - this affects all Firefox Sync clients.
+findViewById<View>(R.id.globallyDisableHistoryEngine).setOnClickListener {
+    SyncEnginesStorage.setStatus(SyncEngine.History, false)
+    accountManager.syncNowAsync(SyncReason.EngineChange)
+}
+
+// Get current status of SyncEngines. Note that this may change after every sync, as other Firefox Sync clients can change it.
+val engineStatusMap = SyncEnginesStorage.getStatus() // type is: Map<SyncEngine, Boolean>
+
 // This is expected to be called from the webview/geckoview integration, which intercepts page loads and gets
 // 'code' and 'state' out of the 'successful sign-in redirect' url.
 fun onLoginComplete(code: String, state: String) {

components/service/firefox-accounts/build.gradle

@@ -33,9 +33,11 @@ dependencies {
 
     // Parts of this dependency are typealiase'd or are otherwise part of this module's public API.
     api Dependencies.mozilla_fxa
+    implementation Dependencies.mozilla_sync_manager
 
     // Observable is part of public API of the FxaAccountManager.
     api project(':support-base')
+    implementation project(':support-sync-telemetry')
     implementation project(':support-ktx')
 
     implementation Dependencies.kotlin_stdlib

components/service/firefox-accounts/src/main/java/mozilla/components/service/fxa/Config.kt

@@ -44,14 +44,24 @@ data class SyncConfig(
 
 /**
  * Describes possible sync engines that device can support.
+ *
  * @property nativeName Internally, Rust SyncManager represents engines as strings. Forward-compatibility
  * with new engines is one of the reasons for this. E.g. during any sync, an engine may appear that we
  * do not know about. At the public API level, we expose a concrete [SyncEngine] type to allow for more
  * robust integrations. We do not expose "unknown" engines via our public API, but do handle them
  * internally (by persisting their enabled/disabled status).
 */
-enum class SyncEngine(val nativeName: String) {
-    HISTORY("history"),
-    BOOKMARKS("bookmarks"),
-    PASSWORDS("passwords"),
+sealed class SyncEngine(val nativeName: String) {
+    // When adding new types, make sure to think through implications for the SyncManager.
+    // See https://github.com/mozilla-mobile/android-components/issues/4557
+    object History : SyncEngine("history")
+    object Bookmarks : SyncEngine("bookmarks")
+    object Passwords : SyncEngine("passwords")
+    data class Other(val name: String) : SyncEngine(name)
+
+    /**
+     * This engine is used internally, but hidden from the public API because we don't fully support
+     * this data type right now.
+     */
+    internal object Forms : SyncEngine("forms")
 }

components/service/firefox-accounts/src/main/java/mozilla/components/service/fxa/FxaDeviceConstellation.kt

@@ -4,6 +4,7 @@
 
 package mozilla.components.service.fxa
 
+import android.content.Context
 import androidx.annotation.GuardedBy
 import androidx.lifecycle.LifecycleOwner
 import kotlinx.coroutines.CoroutineScope
@@ -81,11 +82,12 @@ class FxaDeviceConstellation(
         deviceObserverRegistry.register(observer, owner, autoPause)
     }
 
-    override fun setDeviceNameAsync(name: String): Deferred<Boolean> {
+    override fun setDeviceNameAsync(name: String, context: Context): Deferred<Boolean> {
         return scope.async {
             val rename = handleFxaExceptions(logger, "changing device name") {
                 account.setDeviceDisplayName(name)
             }
+            FxaDeviceSettingsCache(context).updateCachedName(name)
             // See the latest device (name) changes after changing it.
             val refreshDevices = refreshDevicesAsync().await()
 

components/service/firefox-accounts/src/main/java/mozilla/components/service/fxa/FxaDeviceSettingsCache.kt

+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+package mozilla.components.service.fxa
+
+import android.content.Context
+import android.content.SharedPreferences
+import mozilla.appservices.syncmanager.DeviceSettings
+import mozilla.appservices.syncmanager.DeviceType
+import mozilla.components.support.base.log.logger.Logger
+import mozilla.components.support.base.utils.SharedPreferencesCache
+import org.json.JSONObject
+import java.lang.IllegalArgumentException
+import java.lang.IllegalStateException
+
+private const val CACHE_NAME = "FxaDeviceSettingsCache"
+private const val CACHE_KEY = CACHE_NAME
+private const val KEY_FXA_DEVICE_ID = "kid"
+private const val KEY_DEVICE_NAME = "syncKey"
+private const val KEY_DEVICE_TYPE = "tokenServerUrl"
+
+/**
+ * A thin wrapper around [SharedPreferences] which knows how to serialize/deserialize [DeviceSettings].
+ *
+ * This class exists to provide background sync workers with access to [DeviceSettings].
+ */
+class FxaDeviceSettingsCache(context: Context) : SharedPreferencesCache<DeviceSettings>(context) {
+    override val logger = Logger("SyncAuthInfoCache")
+    override val cacheKey = CACHE_KEY
+    override val cacheName = CACHE_NAME
+
+    override fun DeviceSettings.toJSON(): JSONObject {
+        return JSONObject().also {
+            it.put(KEY_FXA_DEVICE_ID, this.fxaDeviceId)
+            it.put(KEY_DEVICE_NAME, this.name)
+            it.put(KEY_DEVICE_TYPE, this.type.name)
+        }
+    }
+
+    override fun fromJSON(obj: JSONObject): DeviceSettings {
+        return DeviceSettings(
+            fxaDeviceId = obj.getString(KEY_FXA_DEVICE_ID),
+            name = obj.getString(KEY_DEVICE_NAME),
+            type = obj.getString(KEY_DEVICE_TYPE).toDeviceType()
+        )
+    }
+
+    /**
+     * @param name New device name to write into the cache.
+     */
+    fun updateCachedName(name: String) {
+        val cached = getCached() ?: throw IllegalStateException("Trying to update cached value in an empty cache")
+        setToCache(cached.copy(name = name))
+    }
+
+    private fun String.toDeviceType(): DeviceType {
+        return when (this) {
+            "DESKTOP" -> DeviceType.DESKTOP
+            "MOBILE" -> DeviceType.MOBILE
+            "TABLET" -> DeviceType.TABLET
+            "VR" -> DeviceType.VR
+            "TV" -> DeviceType.TV
+            else -> throw IllegalArgumentException("Unknown device type in cached string: $this")
+        }
+    }
+}

components/service/firefox-accounts/src/main/java/mozilla/components/service/fxa/SyncAuthInfoCache.kt

@@ -7,7 +7,7 @@ import android.content.Context
 import android.content.SharedPreferences
 import mozilla.components.concept.sync.SyncAuthInfo
 import mozilla.components.support.base.log.logger.Logger
-import org.json.JSONException
+import mozilla.components.support.base.utils.SharedPreferencesCache
 import org.json.JSONObject