add europe beta front test and prevent users seeing the beta front un…

…less opted into test (#27536)

common/app/experiments/Experiments.scala

@@ -13,6 +13,7 @@ object ActiveExperiments extends ExperimentsDefinition {
     Set(
       RemoveLiteFronts,
       MastheadWithHighlights,
+      EuropeBetaFront,
       DarkModeWeb,
     )
   implicit val canCheckExperiment: CanCheckExperiment = new CanCheckExperiment(this)
@@ -28,6 +29,19 @@ object MastheadWithHighlights
       participationGroup = Perc50,
     )
 
+object EuropeBetaFront
+    extends Experiment(
+      name = "europe-beta-front",
+      description = "Allows viewing the beta version of the Europe network front",
+      owners = Seq(
+        Owner.withGithub("cemms1"),
+        Owner.withEmail("[email protected]"),
+        Owner.withEmail("[email protected]"),
+      ),
+      sellByDate = LocalDate.of(2025, 4, 2),
+      participationGroup = Perc0A,
+    )
+
 object DarkModeWeb
     extends Experiment(
       name = "dark-mode-web",

facia/app/controllers/FaciaController.scala

@@ -6,7 +6,7 @@ import common._
 import conf.Configuration
 import conf.switches.Switches.InlineEmailStyles
 import controllers.front._
-import experiments.{ActiveExperiments, RemoveLiteFronts}
+import experiments.{ActiveExperiments, EuropeBetaFront, RemoveLiteFronts}
 import http.HttpPreconnections
 import implicits.GUHeaders
 import layout.slices._
@@ -223,6 +223,13 @@ trait FaciaController
   private[controllers] def renderFrontPressResult(path: String)(implicit request: RequestHeader): Future[Result] = {
     val NonAdFreeType = if (ActiveExperiments.isParticipating(RemoveLiteFronts)) FullType else LiteType
 
+    // Europe beta experiment
+    // Phase 1 prevents users from being able to view the europe-beta front unless opted into the test
+    val inEuropeBetaTest = ActiveExperiments.isParticipating(EuropeBetaFront)
+    if (path == "europe-beta" && !inEuropeBetaTest) {
+      return successful(Cached(CacheTime.NotFound)(WithoutRevalidationResult(NotFound)))
+    }
+
     val futureFaciaPage: Future[Option[(PressedPage, Boolean)]] = frontJsonFapi.get(path, requestType).flatMap {
       case Some(faciaPage: PressedPage) =>
         val pageContainsTargetedCollections = TargetedCollections.pageContainsTargetedCollections(faciaPage)