Show notification with error log on update failures

app/src/main/java/eu/kanade/tachiyomi/data/library/LibraryUpdateNotifier.kt

@@ -6,6 +6,7 @@ import android.content.Context
 import android.content.Intent
 import android.graphics.Bitmap
 import android.graphics.BitmapFactory
+import android.net.Uri
 import androidx.core.app.NotificationCompat
 import androidx.core.app.NotificationManagerCompat
 import com.bumptech.glide.Glide
@@ -80,6 +81,39 @@ class LibraryUpdateNotifier(private val context: Context) {
         )
     }
 
+    /**
+     * Shows notification containing update entries that failed with action to open full log.
+     *
+     * @param errors List of entry titles that failed to update.
+     * @param uri Uri for error log file containing all titles that failed.
+     */
+    fun showUpdateErrorNotification(errors: List<String>, uri: Uri) {
+        if (errors.isEmpty()) {
+            return
+        }
+
+        context.notificationManager.notify(
+            Notifications.ID_LIBRARY_ERROR,
+            context.notificationBuilder(Notifications.CHANNEL_LIBRARY) {
+                setContentTitle(context.resources.getQuantityString(R.plurals.notification_update_error, errors.size, errors.size))
+                setStyle(
+                    NotificationCompat.BigTextStyle().bigText(
+                        errors.joinToString("\n") {
+                            it.chop(NOTIF_TITLE_MAX_LEN)
+                        }
+                    )
+                )
+                setSmallIcon(R.drawable.ic_tachi)
+                addAction(
+                    R.drawable.nnf_ic_file_folder,
+                    context.getString(R.string.action_open_log),
+                    NotificationReceiver.openErrorLogPendingActivity(context, uri)
+                )
+            }
+                .build()
+        )
+    }
+
     /**
      * Shows the notification containing the result of the update done by the service.
      *

app/src/main/java/eu/kanade/tachiyomi/data/library/LibraryUpdateService.kt

@@ -23,8 +23,10 @@ import eu.kanade.tachiyomi.source.SourceManager
 import eu.kanade.tachiyomi.source.model.SManga
 import eu.kanade.tachiyomi.util.chapter.syncChaptersWithSource
 import eu.kanade.tachiyomi.util.prepUpdateCover
+import eu.kanade.tachiyomi.util.storage.getUriCompat
 import eu.kanade.tachiyomi.util.system.acquireWakeLock
 import eu.kanade.tachiyomi.util.system.isServiceRunning
+import java.io.File
 import java.util.ArrayList
 import java.util.concurrent.atomic.AtomicInteger
 import rx.Observable
@@ -253,7 +255,7 @@ class LibraryUpdateService(
         // List containing new updates
         val newUpdates = ArrayList<Pair<LibraryManga, Array<Chapter>>>()
         // List containing failed updates
-        val failedUpdates = ArrayList<Manga>()
+        val failedUpdates = ArrayList<Pair<Manga, String?>>()
         // List containing categories that get included in downloads.
         val categoriesToDownload = preferences.downloadNewCategories().get().map(String::toInt)
         // Boolean to determine if user wants to automatically download new chapters.
@@ -270,7 +272,7 @@ class LibraryUpdateService(
                 updateManga(manga)
                     // If there's any error, return empty update and continue.
                     .onErrorReturn {
-                        failedUpdates.add(manga)
+                        failedUpdates.add(Pair(manga, it.message))
                         Pair(emptyList(), emptyList())
                     }
                     // Filter out mangas without new chapters (or failed).
@@ -303,6 +305,8 @@ class LibraryUpdateService(
             }
             // Notify result of the overall update.
             .doOnCompleted {
+                notifier.cancelProgressNotification()
+
                 if (newUpdates.isNotEmpty()) {
                     notifier.showUpdateNotifications(newUpdates)
                     if (downloadNew && hasDownloads) {
@@ -311,10 +315,12 @@ class LibraryUpdateService(
                 }
 
                 if (failedUpdates.isNotEmpty()) {
-                    Timber.e("Failed updating: ${failedUpdates.map { it.title }}")
+                    val errorFile = writeErrorFile(failedUpdates)
+                    notifier.showUpdateErrorNotification(
+                        failedUpdates.map { it.first.title },
+                        errorFile.getUriCompat(this)
+                    )
                 }
-
-                notifier.cancelProgressNotification()
             }
             .map { manga -> manga.first }
     }
@@ -417,4 +423,25 @@ class LibraryUpdateService(
                 notifier.cancelProgressNotification()
             }
     }
+
+    /**
+     * Writes basic file of update errors to cache dir.
+     */
+    private fun writeErrorFile(errors: List<Pair<Manga, String?>>): File {
+        try {
+            if (errors.isNotEmpty()) {
+                val destFile = File(externalCacheDir, "tachiyomi_update_errors.txt")
+
+                destFile.bufferedWriter().use { out ->
+                    errors.forEach { (manga, error) ->
+                        out.write("${manga.title}: $error\n")
+                    }
+                }
+                return destFile
+            }
+        } catch (e: Exception) {
+            // Empty
+        }
+        return File("")
+    }
 }

app/src/main/java/eu/kanade/tachiyomi/data/notification/Notifications.kt

@@ -25,6 +25,7 @@ object Notifications {
      */
     const val CHANNEL_LIBRARY = "library_channel"
     const val ID_LIBRARY_PROGRESS = -101
+    const val ID_LIBRARY_ERROR = -102
 
     /**
      * Notification channel and ids used by the downloader.