Include duck AI chat deletions in sync engine

[CDRussell]

Task/Issue URL: https://app.asana.com/1/137249556945/project/72649045549333/task/1212290226255075?focus=true

Description

Ensures sync backend is aware of fire button usage (and automatic data clearing) so duck chat deletions can be synced.

Steps to test this PR

Logcat filter:

message~:"duck AI chats cleared|recorded deletion timestamp|cleared local deletion|successfully informed sync of deleted duck ai chats|Duck AI chats deletion sync successful"

Sync disabled / fire button

• Fresh install internal flavor from this branch
• Visit Settings -> Data Clearing and enable Clear Duck.ai Chats toggle
• Return to home, and tap on duck ai chat button. Type a message and send it so there is a chat history.
• Return to home, and use the native fire button to clear data
• Verify in the logs that you see duck AI chats cleared: true
• Verify you see in the logs recorded deletion timestamp with a timestamp that was very recently (e.g., some milliseconds ago)
• Verify you do not see Duck AI chats deletion sync successful (because sync isn't enabled)

Sync disabled / automatic data clearing

• Visit Settings -> Data Clearing and tap on Automatically Clear Data... and choose Tabs, data and Duck.ai chats
• Tap Clear on... and choose the bottom option with 5 seconds
• Return to home, and tap on duck ai chat button. Type a message and send it so there is a chat history.
• Background the app and wait 5 seconds
• Verify you see in the logs recorded deletion timestamp with a timestamp that was a few seconds ago (e.g., 4.5s - 5s ago); we use the timestamp when the app goes to background in the case of automatic data clearing

Sync enabled / fire button

• Enable sync (Settings -> Sync & Backup -> Sync and Back Up This Device)
• Return to home, and tap on duck ai chat button. Type a message and send it so there is a chat history.
• Return to home, and use the native fire button to clear data
• Verify in logs you see Duck AI chats deletion sync successful
• Verify in logs you see cleared local deletion timestamp

Smoke test sync generally

• e.g., sync two devices and add a password; make sure it syncs across

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Note

Adds end-to-end support to record, expose, and sync Duck AI chat deletions (local clear → timestamp → sync DELETE /sync/ai_chats), with engine and API extensions plus feature gating.

• Sync Engine & API:
  • Introduce deletions pipeline: new DeletableType (DUCK_AI_CHATS), DeletableDataManager, and engine flow to process deletions before changes.
  • Extend models to SyncFeatureType and update SyncDeletionRequest/Response to use DeletableType.
  • Add endpoint DELETE /sync/ai_chats (SyncService, SyncServiceRemote, SyncApiClient.delete), including error recording/pixels generalized to SyncFeatureType.
  • Add plugin point for DeletableDataManager and tests across engine/client.
• Duck Chat:
  • New DuckAiChatDeletionListener API and plugin point (BrowserModule).
  • WebLocalStorageManager now detects and deletes Duck AI chat keys and notifies listeners on deletion.
  • Implement listener DuckAiChatDeletionListenerImpl to capture app background timestamp and record deletions via DuckChatSyncRepository/DuckChatSyncMetadataStore.
  • DuckChatSyncDataManager surfaces pending deletions to sync and clears timestamp on success; gated by DuckChatFeature.supportsSyncChatsDeletion().
  • RealDuckChat exposes isChatSyncFeatureEnabled using DeviceSyncState.isDuckChatSyncFeatureEnabled.
• Sync feature flags:
  • Add SyncFeature.aiChatSync() and SyncFeatureToggle.allowAiChatSync() used by AppDeviceSyncState.isDuckChatSyncFeatureEnabled(); add method to DeviceSyncState (and fake impl).
• Tests:
  • Extensive unit tests for local storage deletion notifications, Duck Chat sync repository/manager, sync engine deletions, API client, and feature toggles.

^{Written by Cursor Bugbot for commit 3dfdcb3. This will update automatically on new commits. Configure here.}

[CDRussell]

• Allow duck ai chat syncing (Internal) #7377
• Extend sync crypto to support byte arrays #7375
• Include duck AI chat deletions in sync engine #7354 👈 (View in Graphite)
• Update sync APIs to support deletions #7340
• develop

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[malmstein]

I haven’t tested the functionality yet, just reviewed the code. I don’t understand why you need to store timestamp out of MainProcessLifecycleObserver, maybe we can chat tomorrow.

[CDRussell]

I don’t understand why you need to store timestamp out of MainProcessLifecycleObserver

We want the timestamp when app is going to the background because if the automatic data clearing is used then that is the timestamp that is used for the until parameter. When the fire button is used, we use the current time as the until timestamp.

[cursor]

Bug: Second clearWebLocalStorage overload doesn't notify deletion listeners

The clearWebLocalStorage(shouldClearBrowserData, shouldClearDuckAiData) overload deletes duck AI data when shouldClearDuckAiData is true (lines 152-156) but does not notify the duckAiChatDeletionListeners. Only the first overload clearWebLocalStorage() (lines 76-120) was updated to track deletions with duckAiDataDeleted and notify listeners. This means duck AI chat deletions via this second code path won't be synced to other devices, breaking the sync feature for scenarios that use this overload.

---

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app/src/main/java/com/duckduckgo/app/browser/weblocalstorage/WebLocalStorageManager.kt#L121-L161

Android/app/src/main/java/com/duckduckgo/app/browser/weblocalstorage/WebLocalStorageManager.kt

Lines 121 to 161 in 29fc78f

	override suspend fun clearWebLocalStorage(
	shouldClearBrowserData: Boolean,
	shouldClearDuckAiData: Boolean,
	) {
	withContext(dispatcherProvider.io()) {
	val settings = androidBrowserConfigFeature.webLocalStorage().getSettings()
	val webLocalStorageSettings = webLocalStorageSettingsJsonParser.parseJson(settings)
	val fireproofedDomains = fireproofWebsiteRepository.fireproofWebsitesSync().map { it.domain }
	domains = webLocalStorageSettings.domains.list + fireproofedDomains
	keysToDelete = webLocalStorageSettings.keysToDelete.list
	matchingRegex = webLocalStorageSettings.matchingRegex.list
	logcat { "WebLocalStorageManager: Allowed domains: $domains" }
	logcat { "WebLocalStorageManager: Keys to delete: $keysToDelete" }
	logcat { "WebLocalStorageManager: Matching regex: $matchingRegex" }
	val db = databaseProvider.get()
	db.iterator().use { iterator ->
	iterator.seekToFirst()
	while (iterator.hasNext()) {
	val entry = iterator.next()
	val key = String(entry.key, StandardCharsets.UTF_8)
	val domainForMatchingAllowedKey = getDomainForMatchingAllowedKey(key)
	if (domainForMatchingAllowedKey == null && shouldClearBrowserData) {
	db.delete(entry.key)
	logcat { "WebLocalStorageManager: Deleted key: $key" }
	} else if (shouldClearDuckAiData && DUCKDUCKGO_DOMAINS.contains(domainForMatchingAllowedKey)) {
	if (keysToDelete.any { key.endsWith(it) }) {
	db.delete(entry.key)
	logcat { "WebLocalStorageManager: Deleted key: $key" }
	}
	}
	}
	}
	}
	}

 

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[malmstein]

This is great, thanks for taking the feedback @CDRussell !

[cursor]

Bug: Background timestamp lost if user foregrounds during clearing

When automatic data clearing runs while the app is backgrounded, onStart (main thread) could clear appBackgroundedTimestamp before onDuckAiChatsDeleted (IO thread) reads it. In this scenario, the deletion timestamp falls back to System.currentTimeMillis() instead of the intended background timestamp. The PR description explicitly states the background timestamp should be used for automatic clearing, so this timing issue deviates from the stated behavior.

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Additional Locations (1)

• duckchat/duckchat-impl/src/main/java/com/duckduckgo/duckchat/impl/sync/DuckAiChatDeletionListenerImpl.kt#L47-L51