delete unreferenced icons periodically and download updates every 24 hours

app/src/main/java/io/heckel/ntfy/db/Database.kt

@@ -380,8 +380,14 @@ interface NotificationDao {
     @Query("SELECT * FROM notification WHERE deleted = 1 AND attachment_contentUri <> ''")
     fun listDeletedWithAttachments(): List<Notification>
 
-    @Query("SELECT * FROM notification WHERE deleted = 1 AND icon_contentUri <> ''")
-    fun listDeletedWithIcons(): List<Notification>
+    @Query("SELECT DISTINCT icon_contentUri FROM notification WHERE deleted != 1 AND icon_contentUri <> ''")
+    fun listActiveIconUris(): List<String>
+
+    @Query("SELECT DISTINCT icon_contentUri FROM notification WHERE deleted = 1 AND icon_contentUri <> ''")
+    fun listDeletedIconUris(): List<String>
+
+    @Query("UPDATE notification SET icon_contentUri = null WHERE icon_contentUri = :uri")
+    fun clearIconUri(uri: String)
 
     @Insert(onConflict = OnConflictStrategy.IGNORE)
     fun add(notification: Notification)

app/src/main/java/io/heckel/ntfy/db/Repository.kt

@@ -92,8 +92,16 @@ class Repository(private val sharedPrefs: SharedPreferences, private val databas
         return notificationDao.listDeletedWithAttachments()
     }
 
-    fun getDeletedNotificationsWithIcons(): List<Notification> {
-        return notificationDao.listDeletedWithIcons()
+    fun getActiveIconUris(): Set<String> {
+        return notificationDao.listActiveIconUris().toSet()
+    }
+
+    fun getDeletedIconUris(): Set<String> {
+        return notificationDao.listDeletedIconUris().toSet()
+    }
+
+    fun clearIconUri(uri: String) {
+        notificationDao.clearIconUri(uri)
     }
 
     fun getNotificationsLiveData(subscriptionId: Long): LiveData<List<Notification>> {

app/src/main/java/io/heckel/ntfy/msg/DownloadIconWorker.kt

@@ -14,11 +14,12 @@ import io.heckel.ntfy.R
 import io.heckel.ntfy.app.Application
 import io.heckel.ntfy.db.*
 import io.heckel.ntfy.util.Log
-import io.heckel.ntfy.util.stringToHash
+import io.heckel.ntfy.util.sha256
 import okhttp3.OkHttpClient
 import okhttp3.Request
 import okhttp3.Response
 import java.io.File
+import java.util.Date
 import java.util.concurrent.TimeUnit
 
 class DownloadIconWorker(private val context: Context, params: WorkerParameters) : Worker(context, params) {
@@ -45,7 +46,8 @@ class DownloadIconWorker(private val context: Context, params: WorkerParameters)
         icon = notification.icon ?: return Result.failure()
         try {
             val iconFile = createIconFile(icon)
-            if (!iconFile.exists()) {
+            val yesterdayTimestamp = Date().time - 1000*60*60*24 // now Unix timestamp - 24 hours
+            if (!iconFile.exists() || iconFile.lastModified() < yesterdayTimestamp) {
                 downloadIcon(iconFile)
             } else {
                 Log.d(TAG, "Loading icon from cache: ${icon.url}")
@@ -152,7 +154,7 @@ class DownloadIconWorker(private val context: Context, params: WorkerParameters)
         if (!iconDir.exists() && !iconDir.mkdirs()) {
             throw Exception("Cannot create cache directory for icons: $iconDir")
         }
-        val hash = stringToHash(icon.url)
+        val hash = icon.url.sha256()
         return File(iconDir, hash)
     }
 

app/src/main/java/io/heckel/ntfy/msg/NotificationParser.kt

@@ -50,11 +50,7 @@ class NotificationParser {
                 )
             }
         } else null
-        val icon: Icon? = if (message.icon != null) {
-            Icon(
-                url = message.icon
-            )
-        } else null
+        val icon: Icon? = if (message.icon != null) Icon(url = message.icon) else null
         val notification = Notification(
             id = message.id,
             subscriptionId = subscriptionId,

app/src/main/java/io/heckel/ntfy/util/Util.kt

@@ -471,9 +471,8 @@ fun copyToClipboard(context: Context, notification: Notification) {
         .show()
 }
 
-fun stringToHash(s: String): String {
-    val bytes = s.toByteArray();
+fun String.sha256(): String {
     val md = MessageDigest.getInstance("SHA-256")
-    val digest = md.digest(bytes)
+    val digest = md.digest(this.toByteArray())
     return digest.fold("") { str, it -> str + "%02x".format(it) }
 }

app/src/main/java/io/heckel/ntfy/work/DeleteWorker.kt

@@ -33,7 +33,6 @@ class DeleteWorker(ctx: Context, params: WorkerParameters) : CoroutineWorker(ctx
             deleteExpiredIcons() // Before notifications, so we will also catch manually deleted notifications
             deleteExpiredAttachments() // Before notifications, so we will also catch manually deleted notifications
             deleteExpiredNotifications()
-            cleanIconCache()
             return@withContext Result.success()
         }
     }
@@ -68,40 +67,19 @@ class DeleteWorker(ctx: Context, params: WorkerParameters) : CoroutineWorker(ctx
         Log.d(TAG, "Deleting icons for deleted notifications")
         val resolver = applicationContext.contentResolver
         val repository = Repository.getInstance(applicationContext)
-        val notifications = repository.getDeletedNotificationsWithIcons()
-        notifications.forEach { notification ->
+        val activeIconUris = repository.getActiveIconUris()
+        val expiredIconUris = repository.getDeletedIconUris()
+        val urisToDelete = expiredIconUris.minus(activeIconUris)
+        urisToDelete.forEach { uri ->
             try {
-                val icon = notification.icon ?: return
-                val contentUri = Uri.parse(icon.contentUri ?: return)
-                Log.d(TAG, "Deleting icon for notification ${notification.id}: ${icon.contentUri} (${icon.url})")
-                val deleted = resolver.delete(contentUri, null, null) > 0
+                val deleted = resolver.delete(Uri.parse(uri), null, null) > 0
                 if (!deleted) {
-                    Log.w(TAG, "Unable to delete icon for notification ${notification.id}")
+                    Log.w(TAG, "Unable to delete icon at $uri")
                 }
-                val newIcon = icon.copy(
-                    contentUri = null,
-                )
-                val newNotification = notification.copy(icon = newIcon)
-                repository.updateNotification(newNotification)
+
+                repository.clearIconUri(uri)
             } catch (e: Exception) {
-                Log.w(TAG, "Failed to delete icon for notification: ${e.message}", e)
-            }
-        }
-    }
-
-    private fun cleanIconCache() {
-        Log.d(DeleteWorker.TAG, "Cleaning icons older than 24 hours from cache")
-        val iconDir = File(applicationContext.cacheDir, DownloadIconWorker.ICON_CACHE_DIR)
-        if (iconDir.exists()) {
-            for (f: File in iconDir.listFiles()) {
-                var lastModified = f.lastModified()
-                var today = Date()
-
-                var diffInHours = ((today.time - lastModified) / (1000 * 60 * 60))
-                if (diffInHours > 24) {
-                    Log.d(DeleteWorker.TAG, "Deleting cached icon: ${f.name}")
-                    f.delete()
-                }
+                Log.w(TAG, "Failed to delete icon: ${e.message}", e)
             }
         }
     }

app/src/main/res/values/strings.xml

@@ -165,7 +165,6 @@
     <string name="detail_item_download_info_download_failed">download failed</string>
     <string name="detail_item_download_info_download_failed_expired">download failed, link expired</string>
     <string name="detail_item_download_info_download_failed_expires_x">download failed, link expires %1$s</string>
-    <string name="detail_item_icon_download_failed">Could not download icon: %1$s</string>
 
     <!-- Detail activity: Action bar -->
     <string name="detail_menu_notifications_enabled">Notifications on</string>