Fix storing empty-trash task

It was wrongly stored using RPeriodicTask directly, but the higher
level `UserTask` must be used instead, because this ensures a
correctly scoped periodic task using the `updateOneTask` method. Since
this is a system task, it can be given a fixed ID which makes it now
safe even if stored using RPeriodicTask directly.

The bug resulted in multiple empty-trash tasks to be inserted (on each
restart).

Refs: #347

modules/joex/src/main/scala/docspell/joex/JoexAppImpl.scala

@@ -40,6 +40,8 @@ import docspell.store.records.{REmptyTrashSetting, RJobLog}
 import emil.javamail._
 import org.http4s.blaze.client.BlazeClientBuilder
 import org.http4s.client.Client
+import docspell.store.usertask.UserTaskStore
+import docspell.store.usertask.UserTaskScope
 
 final class JoexAppImpl[F[_]: Async](
     cfg: Config,
@@ -91,9 +93,15 @@ final class JoexAppImpl[F[_]: Async](
         REmptyTrashSetting.findForAllCollectives(OCollective.EmptyTrash.default, 50)
       )
       .evalMap(es =>
-        EmptyTrashTask.periodicTask(EmptyTrashArgs(es.cid, es.minAge), es.schedule)
+        UserTaskStore(store).use { uts =>
+          val args = EmptyTrashArgs(es.cid, es.minAge)
+          uts.updateOneTask(
+            UserTaskScope(args.collective),
+            args.makeSubject.some,
+            EmptyTrashTask.userTask(args, es.schedule)
+          )
+        }
       )
-      .evalMap(pstore.insert)
       .compile
       .drain
 

modules/joex/src/main/scala/docspell/joex/emptytrash/EmptyTrashTask.scala

@@ -13,8 +13,8 @@ import fs2.Stream
 import docspell.backend.ops.{OItem, OItemSearch}
 import docspell.common._
 import docspell.joex.scheduler._
-import docspell.store.records.{RItem, RPeriodicTask}
-import docspell.store.usertask.{UserTask, UserTaskScope}
+import docspell.store.records.RItem
+import docspell.store.usertask.UserTask
 
 import com.github.eikek.calev.CalEvent
 
@@ -26,19 +26,15 @@ object EmptyTrashTask {
 
   private val pageSize = 20
 
-  def periodicTask[F[_]: Sync](args: EmptyTrashArgs, ce: CalEvent): F[RPeriodicTask] =
-    Ident
-      .randomId[F]
-      .flatMap(id =>
-        UserTask(
-          id,
-          EmptyTrashArgs.taskName,
-          true,
-          ce,
-          None,
-          args
-        ).encode.toPeriodicTask(UserTaskScope(args.collective), args.makeSubject.some)
-      )
+  def userTask(args: EmptyTrashArgs, ce: CalEvent): UserTask[EmptyTrashArgs] =
+    UserTask(
+      args.periodicTaskId,
+      EmptyTrashArgs.taskName,
+      true,
+      ce,
+      None,
+      args
+    )
 
   def apply[F[_]: Async](
       itemOps: OItem[F],