Provide tasks with ability to return data and human message

To allow better communication from background tasks, tasks can return
not only data (json), but also a human readable message which is send
via notification channels

modules/notification/api/src/main/scala/docspell/notification/api/Event.scala

@@ -204,7 +204,8 @@ object Event {
       state: JobState,
       subject: String,
       submitter: Ident,
-      result: Json
+      resultData: Json,
+      resultMsg: Option[String]
   ) extends Event {
     val eventType = JobDone
     val baseUrl = None
@@ -222,7 +223,8 @@ object Event {
           JobState.running,
           "Process 3 files",
           account.user,
-          Json.Null
+          Json.Null,
+          None
         )
       } yield ev
   }

modules/notification/api/src/main/scala/docspell/notification/api/EventContext.scala

@@ -31,30 +31,25 @@ trait EventContext {
       "content" -> content
     )
 
-  def defaultTitle: Either[String, String]
-  def defaultTitleHtml: Either[String, String]
-
-  def defaultBody: Either[String, String]
-  def defaultBodyHtml: Either[String, String]
+  def defaultMessage: Either[String, EventMessage]
+  def defaultMessageHtml: Either[String, EventMessage]
 
   def defaultBoth: Either[String, String]
   def defaultBothHtml: Either[String, String]
 
   lazy val asJsonWithMessage: Either[String, Json] =
     for {
-      tt1 <- defaultTitle
-      tb1 <- defaultBody
-      tt2 <- defaultTitleHtml
-      tb2 <- defaultBodyHtml
+      dm1 <- defaultMessage
+      dm2 <- defaultMessageHtml
       data = asJson
       msg = Json.obj(
         "message" -> Json.obj(
-          "title" -> tt1.asJson,
-          "body" -> tb1.asJson
+          "title" -> dm1.title.asJson,
+          "body" -> dm1.body.asJson
         ),
         "messageHtml" -> Json.obj(
-          "title" -> tt2.asJson,
-          "body" -> tb2.asJson
+          "title" -> dm2.title.asJson,
+          "body" -> dm2.body.asJson
         )
       )
     } yield data.withObject(o1 => msg.withObject(o2 => o1.deepMerge(o2).asJson))
@@ -65,10 +60,8 @@ object EventContext {
     new EventContext {
       val event = ev
       def content = Json.obj()
-      def defaultTitle = Right("")
-      def defaultTitleHtml = Right("")
-      def defaultBody = Right("")
-      def defaultBodyHtml = Right("")
+      def defaultMessage = Right(EventMessage.empty)
+      def defaultMessageHtml = Right(EventMessage.empty)
       def defaultBoth = Right("")
       def defaultBothHtml = Right("")
     }

modules/notification/api/src/main/scala/docspell/notification/api/EventMessage.scala

@@ -0,0 +1,13 @@
+/*
+ * Copyright 2020 Eike K. & Contributors
+ *
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+
+package docspell.notification.api
+
+final case class EventMessage(title: String, body: String)
+
+object EventMessage {
+  val empty: EventMessage = EventMessage("", "")
+}

modules/notification/impl/src/main/scala/docspell/notification/impl/AbstractEventContext.scala

@@ -6,7 +6,7 @@
 
 package docspell.notification.impl
 
-import docspell.notification.api.EventContext
+import docspell.notification.api.{EventContext, EventMessage}
 
 import yamusca.circe._
 import yamusca.implicits._
@@ -24,17 +24,17 @@ abstract class AbstractEventContext extends EventContext {
   def renderHtml(template: Template): String =
     Markdown.toHtml(render(template))
 
-  lazy val defaultTitle: Either[String, String] =
-    titleTemplate.map(render)
+  lazy val defaultMessage: Either[String, EventMessage] =
+    for {
+      title <- titleTemplate.map(render)
+      body <- bodyTemplate.map(render)
+    } yield EventMessage(title, body)
 
-  lazy val defaultTitleHtml: Either[String, String] =
-    titleTemplate.map(renderHtml)
-
-  lazy val defaultBody: Either[String, String] =
-    bodyTemplate.map(render)
-
-  lazy val defaultBodyHtml: Either[String, String] =
-    bodyTemplate.map(renderHtml)
+  lazy val defaultMessageHtml: Either[String, EventMessage] =
+    for {
+      title <- titleTemplate.map(renderHtml)
+      body <- bodyTemplate.map(renderHtml)
+    } yield EventMessage(title, body)
 
   lazy val defaultBoth: Either[String, String] =
     for {

modules/notification/impl/src/main/scala/docspell/notification/impl/EventContextSyntax.scala

@@ -18,8 +18,9 @@ trait EventContextSyntax {
   implicit final class EventContextOps(self: EventContext) {
     def withDefault[F[_]](logger: Logger[F])(f: (String, String) => F[Unit]): F[Unit] =
       (for {
-        tt <- self.defaultTitle
-        tb <- self.defaultBody
+        dm <- self.defaultMessage
+        tt = dm.title
+        tb = dm.body
       } yield f(tt, tb)).fold(logError(logger), identity)
 
     def withJsonMessage[F[_]](logger: Logger[F])(f: Json => F[Unit]): F[Unit] =

modules/notification/impl/src/main/scala/docspell/notification/impl/context/JobDoneCtx.scala

@@ -23,9 +23,14 @@ final case class JobDoneCtx(event: Event.JobDone, data: JobDoneCtx.Data)
   val content = data.asJson
 
   val titleTemplate = Right(mustache"{{eventType}} (by *{{account.user}}*)")
-  val bodyTemplate = Right(
-    mustache"""{{#content}}_'{{subject}}'_ finished {{/content}}"""
-  )
+  val bodyTemplate =
+    data.resultMsg match {
+      case None =>
+        Right(mustache"""{{#content}}_'{{subject}}'_ finished {{/content}}""")
+      case Some(msg) =>
+        val tpl = s"""{{#content}}$msg{{/content}}"""
+        yamusca.imports.mustache.parse(tpl).left.map(_._2)
+    }
 }
 
 object JobDoneCtx {
@@ -46,7 +51,8 @@ object JobDoneCtx {
       state: JobState,
       subject: String,
       submitter: Ident,
-      result: Json
+      resultData: Json,
+      resultMsg: Option[String]
   )
   object Data {
     implicit val jsonEncoder: Encoder[Data] =
@@ -61,7 +67,8 @@ object JobDoneCtx {
         ev.state,
         ev.subject,
         ev.submitter,
-        ev.result
+        ev.resultData,
+        ev.resultMsg
       )
   }
 }

modules/notification/impl/src/test/scala/docspell/notification/impl/context/TagsChangedCtxTest.scala

@@ -46,9 +46,10 @@ class TagsChangedCtxTest extends FunSuite {
       TagsChangedCtx.Data(account, List(item), List(tag), Nil, url.some.map(_.asString))
     )
 
-    assertEquals(ctx.defaultTitle.toOption.get, "TagsChanged (by *user2*)")
+    val dm = ctx.defaultMessage.toOption.get
+    assertEquals(dm.title, "TagsChanged (by *user2*)")
     assertEquals(
-      ctx.defaultBody.toOption.get,
+      dm.body,
       "Adding *tag-red* on [`Report 2`](http://test/item-1)."
     )
   }
@@ -65,9 +66,10 @@ class TagsChangedCtxTest extends FunSuite {
       )
     )
 
-    assertEquals(ctx.defaultTitle.toOption.get, "TagsChanged (by *user2*)")
+    val dm = ctx.defaultMessage.toOption.get
+    assertEquals(dm.title, "TagsChanged (by *user2*)")
     assertEquals(
-      ctx.defaultBody.toOption.get,
+      dm.body,
       "Adding *tag-red*; Removing *tag-blue* on [`Report 2`](http://test/item-1)."
     )
   }