Enhance timeline elements with ids

common/app/model/dotcomrendering/ElementsEnhancer.scala

@@ -2,34 +2,55 @@ package model.dotcomrendering
 
 import play.api.libs.json.{Json, _}
 
-object ElementsEnhancer {
+/**
+  * The `ElementsEnhancer` object provides functions to enhance JSON representations of elements used in Dotcom Rendering.
+  * It adds unique identifiers to elements, as expected by the DCR schemas. More information on the decision for this can be found in PageElement-Identifiers.md or by searching for "03feb394-a17d-4430-8384-edd1891e0d01"
+  *
+ */
 
-  // Note:
-  //     In the file PageElement-Identifiers.md you will find a discussion of identifiers used by PageElements
-  //     Also look for "03feb394-a17d-4430-8384-edd1891e0d01"
+object ElementsEnhancer {
 
   def enhanceElement(element: JsValue): JsValue = {
+    // Add an elementId to the element
     val elementWithId = element.as[JsObject] ++ Json.obj("elementId" -> java.util.UUID.randomUUID.toString)
+    // Extract element type
     val elementType = elementWithId.value("_type").as[String]
-    val elementIsList = elementType == "model.dotcomrendering.pageElements.ListBlockElement"
 
-    if (elementIsList) {
-      val listItems = elementWithId.value("items").as[JsArray]
-      val listItemsWithIds = listItems.value.map { item =>
-        val obj = item.as[JsObject]
-        obj ++ Json.obj("elements" -> enhanceElements(obj.value("elements")))
+    // If element has further nesting, continue to enhance. otherwise, return the enhanced element
+    elementType match {
+      case "model.dotcomrendering.pageElements.ListBlockElement"     => enhanceListBlockElement(elementWithId)
+      case "model.dotcomrendering.pageElements.TimelineBlockElement" => enhanceTimelineBlockElement(elementWithId)
+      case _                                                         => elementWithId;
+    }
+
+  }
+  def enhanceListBlockElement(elementWithId: JsObject): JsObject = {
+    val listItems = elementWithId.value("items").as[JsArray]
+    val listItemsWithIds = listItems.value.map { item =>
+      val obj = item.as[JsObject]
+      obj ++ Json.obj("elements" -> enhanceElements(obj.value("elements")))
+    }
+    elementWithId ++ Json.obj("items" -> listItemsWithIds)
+  }
+
+  def enhanceTimelineBlockElement(element: JsObject): JsObject = {
+    val sectionsList = element.value("sections").as[List[JsObject]]
+    val sectionsListWithIds = sectionsList.map { section =>
+      val eventsList = section.value("events").as[List[JsObject]]
+      val eventsListWithIds = eventsList.map { event =>
+        val bodyElementsWithIds = enhanceElements(event.value("body").as[JsArray])
+        event.as[JsObject] ++ Json.obj("body" -> bodyElementsWithIds)
       }
-      elementWithId ++ Json.obj("items" -> listItemsWithIds)
-    } else {
-      elementWithId
+      section.as[JsObject] ++ Json.obj("events" -> eventsListWithIds)
     }
+    element ++ Json.obj("sections" -> sectionsListWithIds)
   }
 
   def enhanceElements(elements: JsValue): IndexedSeq[JsValue] = {
     elements.as[JsArray].value.map(element => enhanceElement(element))
   }.toIndexedSeq
 
-  def enhanceObjectWithElementsAtDepth1(obj: JsValue): JsValue = {
+  def enhanceObjectWithElements(obj: JsValue): JsValue = {
     obj.asOpt[JsObject] match {
       case Some(o) =>
         val elements = o.value("elements")
@@ -38,21 +59,21 @@ object ElementsEnhancer {
     }
   }
 
-  def enhanceObjectsWithElementsAtDepth1(objs: JsValue): IndexedSeq[JsValue] = {
-    objs.as[JsArray].value.map(obj => enhanceObjectWithElementsAtDepth1(obj))
+  def enhanceObjectsWithElements(objs: JsValue): IndexedSeq[JsValue] = {
+    objs.as[JsArray].value.map(obj => enhanceObjectWithElements(obj))
   }.toIndexedSeq
 
   def enhanceBlocks(obj: JsObject): JsObject = {
     obj ++
-      Json.obj("blocks" -> enhanceObjectsWithElementsAtDepth1(obj.value("blocks")))
+      Json.obj("blocks" -> enhanceObjectsWithElements(obj.value("blocks")))
   }
 
   def enhanceDcrObject(obj: JsObject): JsObject = {
     obj ++
-      Json.obj("blocks" -> enhanceObjectsWithElementsAtDepth1(obj.value("blocks"))) ++
+      Json.obj("blocks" -> enhanceObjectsWithElements(obj.value("blocks"))) ++
       Json.obj("mainMediaElements" -> enhanceElements(obj.value("mainMediaElements"))) ++
-      Json.obj("keyEvents" -> enhanceObjectsWithElementsAtDepth1(obj.value("keyEvents"))) ++
-      Json.obj("pinnedPost" -> enhanceObjectWithElementsAtDepth1(obj.value("pinnedPost"))) ++
+      Json.obj("keyEvents" -> enhanceObjectsWithElements(obj.value("keyEvents"))) ++
+      Json.obj("pinnedPost" -> enhanceObjectWithElements(obj.value("pinnedPost"))) ++
       Json.obj("promotedNewsletter" -> obj.value("promotedNewsletter"))
   }
 }

common/app/model/dotcomrendering/pageElements/PageElement.scala

@@ -877,6 +877,8 @@ object PageElement {
       case _: WitnessBlockElement         => true
       case _: VineBlockElement            => true
       case _: ListBlockElement            => true
+      case _: TimelineBlockElement        => true
+
       // TODO we should quick fail here for these rather than pointlessly go to DCR
       case table: TableBlockElement if table.isMandatory.exists(identity) => true