Allow notification templates to fail

Templates were hardcoded. To make them dynamic, errors must be handled.

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

@@ -31,30 +31,33 @@ trait EventContext {
       "content" -> content
     )
 
-  def defaultTitle: String
+  def defaultTitle: Either[String, String]
-  def defaultTitleHtml: String
+  def defaultTitleHtml: Either[String, String]
 
-  def defaultBody: String
+  def defaultBody: Either[String, String]
-  def defaultBodyHtml: String
+  def defaultBodyHtml: Either[String, String]
 
-  def defaultBoth: String
+  def defaultBoth: Either[String, String]
-  def defaultBothHtml: String
+  def defaultBothHtml: Either[String, String]
 
-  lazy val asJsonWithMessage: Json = {
+  lazy val asJsonWithMessage: Either[String, Json] =
-    val data = asJson
+    for {
-    val msg = Json.obj(
+      tt1 <- defaultTitle
+      tb1 <- defaultBody
+      tt2 <- defaultTitleHtml
+      tb2 <- defaultBodyHtml
+      data = asJson
+      msg = Json.obj(
         "message" -> Json.obj(
-        "title" -> defaultTitle.asJson,
+          "title" -> tt1.asJson,
-        "body" -> defaultBody.asJson
+          "body" -> tb1.asJson
         ),
         "messageHtml" -> Json.obj(
-        "title" -> defaultTitleHtml.asJson,
+          "title" -> tt2.asJson,
-        "body" -> defaultBodyHtml.asJson
+          "body" -> tb2.asJson
         )
       )
-
+    } yield data.withObject(o1 => msg.withObject(o2 => o1.deepMerge(o2).asJson))
-    data.withObject(o1 => msg.withObject(o2 => o1.deepMerge(o2).asJson))
-  }
 }
 
 object EventContext {
@@ -62,12 +65,12 @@ object EventContext {
     new EventContext {
       val event = ev
       def content = Json.obj()
-      def defaultTitle = ""
+      def defaultTitle = Right("")
-      def defaultTitleHtml = ""
+      def defaultTitleHtml = Right("")
-      def defaultBody = ""
+      def defaultBody = Right("")
-      def defaultBodyHtml = ""
+      def defaultBodyHtml = Right("")
-      def defaultBoth: String = ""
+      def defaultBoth = Right("")
-      def defaultBothHtml: String = ""
+      def defaultBothHtml = Right("")
     }
 
   /** For an event, the context can be created that is usually amended with more

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

@@ -14,9 +14,9 @@ import yamusca.imports._
 
 abstract class AbstractEventContext extends EventContext {
 
-  def titleTemplate: Template
+  def titleTemplate: Either[String, Template]
 
-  def bodyTemplate: Template
+  def bodyTemplate: Either[String, Template]
 
   def render(template: Template): String =
     asJson.render(template).trim()
@@ -24,33 +24,39 @@ abstract class AbstractEventContext extends EventContext {
   def renderHtml(template: Template): String =
     Markdown.toHtml(render(template))
 
-  lazy val defaultTitle: String =
+  lazy val defaultTitle: Either[String, String] =
-    render(titleTemplate)
+    titleTemplate.map(render)
 
-  lazy val defaultTitleHtml: String =
+  lazy val defaultTitleHtml: Either[String, String] =
-    renderHtml(titleTemplate)
+    titleTemplate.map(renderHtml)
 
-  lazy val defaultBody: String =
+  lazy val defaultBody: Either[String, String] =
-    render(bodyTemplate)
+    bodyTemplate.map(render)
 
-  lazy val defaultBodyHtml: String =
+  lazy val defaultBodyHtml: Either[String, String] =
-    renderHtml(bodyTemplate)
+    bodyTemplate.map(renderHtml)
 
-  lazy val defaultBoth: String =
+  lazy val defaultBoth: Either[String, String] =
-    render(
+    for {
+      tt <- titleTemplate
+      tb <- bodyTemplate
+    } yield render(
       AbstractEventContext.concat(
-        titleTemplate,
+        tt,
         AbstractEventContext.sepTemplate,
-        bodyTemplate
+        tb
       )
     )
 
-  lazy val defaultBothHtml: String =
+  lazy val defaultBothHtml: Either[String, String] =
-    renderHtml(
+    for {
+      tt <- titleTemplate
+      tb <- bodyTemplate
+    } yield renderHtml(
       AbstractEventContext.concat(
-        titleTemplate,
+        tt,
         AbstractEventContext.sepTemplate,
-        bodyTemplate
+        tb
       )
     )
 }

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

@@ -19,17 +19,19 @@ final class EmailBackend[F[_]: Sync](
     channel: NotificationChannel.Email,
     mailService: Emil[F],
     logger: Logger[F]
-) extends NotificationBackend[F] {
+) extends NotificationBackend[F]
+    with EventContextSyntax {
 
   import emil.builder._
 
-  def send(event: EventContext): F[Unit] = {
+  def send(event: EventContext): F[Unit] =
+    event.withDefault(logger) { (title, body) =>
       val mail =
         MailBuilder.build(
           From(channel.from),
           Tos(channel.recipients.toList),
-        Subject(event.defaultTitle),
+          Subject(title),
-        MarkdownBody[F](event.defaultBody)
+          MarkdownBody[F](body)
         )
 
       logger.debug(s"Attempting to send notification mail: $channel") *>

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

@@ -0,0 +1,30 @@
+package docspell.notification.impl
+
+import docspell.notification.api.EventContext
+import docspell.common.Logger
+import io.circe.Json
+
+trait EventContextSyntax {
+  private def logError[F[_]](logger: Logger[F])(reason: String): F[Unit] =
+    logger.error(s"Unable to send notification, the template failed to render: $reason")
+
+  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
+      } yield f(tt, tb)).fold(logError(logger), identity)
+
+    def withJsonMessage[F[_]](logger: Logger[F])(f: Json => F[Unit]): F[Unit] =
+      self.asJsonWithMessage match {
+        case Right(m)  => f(m)
+        case Left(err) => logError(logger)(err)
+      }
+
+    def withDefaultBoth[F[_]](logger: Logger[F])(f: (String, String) => F[Unit]): F[Unit] =
+      (for {
+        md <- self.defaultBoth
+        html <- self.defaultBothHtml
+      } yield f(md, html)).fold(logError(logger), identity)
+  }
+}

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

@@ -23,17 +23,19 @@ final class GotifyBackend[F[_]: Async](
     channel: NotificationChannel.Gotify,
     client: Client[F],
     logger: Logger[F]
-) extends NotificationBackend[F] {
+) extends NotificationBackend[F]
+    with EventContextSyntax {
 
   val dsl = new Http4sDsl[F] with Http4sClientDsl[F] {}
   import dsl._
 
-  def send(event: EventContext): F[Unit] = {
+  def send(event: EventContext): F[Unit] =
+    event.withDefault(logger) { (title, body) =>
       val url = Uri.unsafeFromString((channel.url / "message").asString)
       val req = POST(
         Json.obj(
-        "title" -> Json.fromString(event.defaultTitle),
+          "title" -> Json.fromString(title),
-        "message" -> Json.fromString(event.defaultBody),
+          "message" -> Json.fromString(body),
           "extras" -> Json.obj(
             "client::display" -> Json.obj(
               "contentType" -> Json.fromString("text/markdown")

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

@@ -21,15 +21,17 @@ final class HttpPostBackend[F[_]: Async](
     channel: NotificationChannel.HttpPost,
     client: Client[F],
     logger: Logger[F]
-) extends NotificationBackend[F] {
+) extends NotificationBackend[F]
+    with EventContextSyntax {
 
   val dsl = new Http4sDsl[F] with Http4sClientDsl[F] {}
   import dsl._
   import org.http4s.circe.CirceEntityCodec._
 
-  def send(event: EventContext): F[Unit] = {
+  def send(event: EventContext): F[Unit] =
+    event.withJsonMessage(logger) { json =>
       val url = Uri.unsafeFromString(channel.url.asString)
-    val req = POST(event.asJsonWithMessage, url).putHeaders(channel.headers.toList)
+      val req = POST(json, url).putHeaders(channel.headers.toList)
       logger.debug(s"$channel sending request: $req") *>
         HttpSend.sendRequest(client, req, channel, logger)
     }

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

@@ -20,13 +20,15 @@ final class MatrixBackend[F[_]: Async](
     channel: NotificationChannel.Matrix,
     client: Client[F],
     logger: Logger[F]
-) extends NotificationBackend[F] {
+) extends NotificationBackend[F]
+    with EventContextSyntax {
 
   val dsl = new Http4sDsl[F] with Http4sClientDsl[F] {}
   import dsl._
   import org.http4s.circe.CirceEntityCodec._
 
-  def send(event: EventContext): F[Unit] = {
+  def send(event: EventContext): F[Unit] =
+    event.withDefaultBoth(logger) { (md, html) =>
       val url =
         (channel.homeServer / "_matrix" / "client" / "r0" / "rooms" / channel.roomId / "send" / "m.room.message")
           .withQuery("access_token", channel.accessToken.pass)
@@ -35,8 +37,8 @@ final class MatrixBackend[F[_]: Async](
         Map(
           "msgtype" -> channel.messageType,
           "format" -> "org.matrix.custom.html",
-        "formatted_body" -> event.defaultBothHtml,
+          "formatted_body" -> html,
-        "body" -> event.defaultBoth
+          "body" -> md
         ),
         uri
       )

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

@@ -30,9 +30,9 @@ final case class DeleteFieldValueCtx(
 
   val content = data.asJson
 
-  val titleTemplate = mustache"{{eventType}} (by *{{account.user}}*)"
+  val titleTemplate = Right(mustache"{{eventType}} (by *{{account.user}}*)")
   val bodyTemplate =
-    mustache"""{{#content}}{{#field.label}}*{{field.label}}* {{/field.label}}{{^field.label}}*{{field.name}}* {{/field.label}} was removed from {{#items}}{{^-first}}, {{/-first}}{{#itemUrl}}[`{{name}}`]({{{itemUrl}}}/{{{id}}}){{/itemUrl}}{{^itemUrl}}`{{name}}`{{/itemUrl}}{{/items}}.{{/content}}"""
+    Right(mustache"""{{#content}}{{#field.label}}*{{field.label}}* {{/field.label}}{{^field.label}}*{{field.name}}* {{/field.label}} was removed from {{#items}}{{^-first}}, {{/-first}}{{#itemUrl}}[`{{name}}`]({{{itemUrl}}}/{{{id}}}){{/itemUrl}}{{^itemUrl}}`{{name}}`{{/itemUrl}}{{/items}}.{{/content}}""")
 
 }
 

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

@@ -25,8 +25,8 @@ final case class ItemSelectionCtx(event: Event.ItemSelection, data: ItemSelectio
 
   val content = data.asJson
 
-  val titleTemplate = mustache"Your items"
+  val titleTemplate = Right(mustache"Your items")
-  val bodyTemplate = mustache"""
+  val bodyTemplate = Right(mustache"""
 Hello {{{ content.username }}},
 
 this is Docspell informing you about your next items.
@@ -51,7 +51,7 @@ this is Docspell informing you about your next items.
 Sincerely yours,
 
 Docspell
-"""
+""")
 }
 
 object ItemSelectionCtx {
@@ -113,5 +113,4 @@ object ItemSelectionCtx {
         account.user.id
       )
   }
-
 }

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

@@ -22,8 +22,8 @@ final case class JobDoneCtx(event: Event.JobDone, data: JobDoneCtx.Data)
 
   val content = data.asJson
 
-  val titleTemplate = mustache"{{eventType}} (by *{{account.user}}*)"
+  val titleTemplate = Right(mustache"{{eventType}} (by *{{account.user}}*)")
-  val bodyTemplate = mustache"""{{#content}}_'{{subject}}'_ finished {{/content}}"""
+  val bodyTemplate = Right(mustache"""{{#content}}_'{{subject}}'_ finished {{/content}}""")
 }
 
 object JobDoneCtx {

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

@@ -22,9 +22,9 @@ final case class JobSubmittedCtx(event: Event.JobSubmitted, data: JobSubmittedCt
 
   val content = data.asJson
 
-  val titleTemplate = mustache"{{eventType}} (by *{{account.user}}*)"
+  val titleTemplate = Right(mustache"{{eventType}} (by *{{account.user}}*)")
   val bodyTemplate =
-    mustache"""{{#content}}_'{{subject}}'_ submitted by {{submitter}} {{/content}}"""
+    Right(mustache"""{{#content}}_'{{subject}}'_ submitted by {{submitter}} {{/content}}""")
 }
 
 object JobSubmittedCtx {

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

@@ -28,9 +28,9 @@ final case class SetFieldValueCtx(event: Event.SetFieldValue, data: SetFieldValu
 
   val content = data.asJson
 
-  val titleTemplate = mustache"{{eventType}} (by *{{account.user}}*)"
+  val titleTemplate = Right(mustache"{{eventType}} (by *{{account.user}}*)")
   val bodyTemplate =
-    mustache"""{{#content}}{{#field.label}}*{{field.label}}* {{/field.label}}{{^field.label}}*{{field.name}}* {{/field.label}} was set to '{{value}}' on {{#items}}{{^-first}}, {{/-first}}{{#itemUrl}}[`{{name}}`]({{{itemUrl}}}/{{{id}}}){{/itemUrl}}{{^itemUrl}}`{{name}}`{{/itemUrl}}{{/items}}.{{/content}}"""
+    Right(mustache"""{{#content}}{{#field.label}}*{{field.label}}* {{/field.label}}{{^field.label}}*{{field.name}}* {{/field.label}} was set to '{{value}}' on {{#items}}{{^-first}}, {{/-first}}{{#itemUrl}}[`{{name}}`]({{{itemUrl}}}/{{{id}}}){{/itemUrl}}{{^itemUrl}}`{{name}}`{{/itemUrl}}{{/items}}.{{/content}}""")
 
 }
 

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

@@ -26,10 +26,9 @@ final case class TagsChangedCtx(event: Event.TagsChanged, data: TagsChangedCtx.D
 
   val content = data.asJson
 
-  val titleTemplate = mustache"{{eventType}} (by *{{account.user}}*)"
+  val titleTemplate = Right(mustache"{{eventType}} (by *{{account.user}}*)")
   val bodyTemplate =
-    mustache"""{{#content}}{{#added}}{{#-first}}Adding {{/-first}}{{^-first}}, {{/-first}}*{{name}}*{{/added}}{{#removed}}{{#added}}{{#-first}};{{/-first}}{{/added}}{{#-first}} Removing {{/-first}}{{^-first}}, {{/-first}}*{{name}}*{{/removed}} on {{#items}}{{^-first}}, {{/-first}}{{#itemUrl}}[`{{name}}`]({{{itemUrl}}}/{{{id}}}){{/itemUrl}}{{^itemUrl}}`{{name}}`{{/itemUrl}}{{/items}}.{{/content}}"""
+    Right(mustache"""{{#content}}{{#added}}{{#-first}}Adding {{/-first}}{{^-first}}, {{/-first}}*{{name}}*{{/added}}{{#removed}}{{#added}}{{#-first}};{{/-first}}{{/added}}{{#-first}} Removing {{/-first}}{{^-first}}, {{/-first}}*{{name}}*{{/removed}} on {{#items}}{{^-first}}, {{/-first}}{{#itemUrl}}[`{{name}}`]({{{itemUrl}}}/{{{id}}}){{/itemUrl}}{{^itemUrl}}`{{name}}`{{/itemUrl}}{{/items}}.{{/content}}""")
-
 }
 
 object TagsChangedCtx {

modules/restserver/src/main/scala/docspell/restserver/routes/NotificationRoutes.scala

@@ -162,7 +162,11 @@ object NotificationRoutes {
           user.account,
           baseUrl.some
         )
-        resp <- Ok(data.asJsonWithMessage)
+        resp <- data.asJsonWithMessage match {
+          case Right(m) => Ok(m)
+          case Left(err) =>
+            BadRequest(BasicResult(false, s"Unable to render message: $err"))
+        }
       } yield resp
     }
   }