consolidate and simplify passthroughs

src/main/scala/org/broadinstitute/dsde/firecloud/FireCloudApiService.scala

@@ -71,20 +71,18 @@ trait FireCloudApiService
     with RegisterApiService
     with WorkspaceApiService
     with WorkspaceV2ApiService
-    with NotificationsApiService
     with MethodConfigurationApiService
-    with BillingApiService
     with SubmissionApiService
     with StatusApiService
     with MethodsApiService
-    with Ga4ghApiService
     with UserApiService
     with ShareLogApiService
     with ManagedGroupApiService
     with CromIamApiService
     with HealthApiService
     with StaticNotebooksApiService
-    with PerimeterApiService {
+    with PerimeterApiService
+    with PassthroughApiService {
 
   override lazy val log = LoggerFactory.getLogger(getClass)
 
@@ -184,7 +182,6 @@ trait FireCloudApiService
           methodConfigurationRoutes ~
           submissionServiceRoutes ~
           nihRoutes ~
-          billingServiceRoutes ~
           shareLogServiceRoutes ~
           staticNotebooksRoutes ~
           perimeterServiceRoutes
@@ -217,14 +214,14 @@ trait FireCloudApiService
       managedGroupServiceRoutes ~
       workspaceRoutes ~
       workspaceV2Routes ~
-      notificationsRoutes ~
       statusRoutes ~
-      ga4ghRoutes ~
       pathPrefix("api") {
         apiRoutes
       } ~
       // insecure cookie-authed routes
-      cookieAuthedRoutes
+      cookieAuthedRoutes ~
+      // wildcard passthrough routes. These must be last to allow other routes to override them.
+      passthroughRoutes
   }
 
 }

src/main/scala/org/broadinstitute/dsde/firecloud/webservice/PassthroughApiService.scala

@@ -0,0 +1,18 @@
+package org.broadinstitute.dsde.firecloud.webservice
+
+import akka.http.scaladsl.server.{Directives, Route}
+import org.broadinstitute.dsde.firecloud.FireCloudConfig
+import org.broadinstitute.dsde.firecloud.utils.StreamingPassthrough
+
+trait PassthroughApiService extends Directives with StreamingPassthrough {
+
+  private lazy val agora = FireCloudConfig.Agora.baseUrl
+  private lazy val rawls = FireCloudConfig.Rawls.baseUrl
+
+  val passthroughRoutes: Route = concat(
+    pathPrefix("ga4gh")(streamingPassthrough(s"$agora/ga4gh")),
+    pathPrefix("api" / "billing")(streamingPassthrough(s"$rawls/api/billing")),
+    pathPrefix("api" / "notifications")(streamingPassthrough(s"$rawls/api/notifications"))
+  )
+
+}