Responding with error when filter is not mounted

tests/wakunode_rest/test_rest_admin.nim

@@ -136,44 +136,6 @@ suite "Waku v2 Rest API - Admin":
       ($getRes.data).contains(expectedFilterData2)
       ($getRes.data).contains(expectedFilterData3)
 
-  asyncTest "Get filter data":
-    await allFutures(node1.mountFilter(), node2.mountFilterClient(), node3.mountFilterClient())
-
-    let
-      contentFiltersNode2 = @[DefaultContentTopic, ContentTopic("2"), ContentTopic("3")]
-      contentFiltersNode3 = @[ContentTopic("3"), ContentTopic("4")]
-      pubsubTopicNode2 = DefaultPubsubTopic
-      pubsubTopicNode3 = PubsubTopic("/waku/2/custom-waku/proto")
-
-      expectedFilterData2 = fmt"(peerId: ""{$peerInfo2}"", filterCriteria:" &
-        fmt" @[(pubsubTopic: ""{pubsubTopicNode2}"", contentTopic: ""{contentFiltersNode2[0]}""), " &
-        fmt"(pubsubTopic: ""{pubsubTopicNode2}"", contentTopic: ""{contentFiltersNode2[1]}""), " &
-        fmt"(pubsubTopic: ""{pubsubTopicNode2}"", contentTopic: ""{contentFiltersNode2[2]}"")]"
-
-      expectedFilterData3 = fmt"(peerId: ""{$peerInfo3}"", filterCriteria:" &
-        fmt" @[(pubsubTopic: ""{pubsubTopicNode3}"", contentTopic: ""{contentFiltersNode3[0]}""), " &
-        fmt"(pubsubTopic: ""{pubsubTopicNode3}"", contentTopic: ""{contentFiltersNode3[1]}"")]"
-
-    let
-      subscribeResponse2 = await node2.wakuFilterClient.subscribe(
-        peerInfo1, pubsubTopicNode2, contentFiltersNode2
-      )
-      subscribeResponse3 = await node3.wakuFilterClient.subscribe(
-        peerInfo1, pubsubTopicNode3, contentFiltersNode3
-      )
-
-    assert subscribeResponse2.isOk(), $subscribeResponse2.error
-    assert subscribeResponse3.isOk(), $subscribeResponse3.error
-
-    let getRes = await client.getFilterSubscriptions()
-
-    check:
-      getRes.status == 200
-      $getRes.contentType == $MIMETYPE_JSON
-      getRes.data.len() == 2
-      ($getRes.data).contains(expectedFilterData2)
-      ($getRes.data).contains(expectedFilterData3)
-
   asyncTest "Get filter data - no filter subscribers":
     await node1.mountFilter()
 
@@ -185,9 +147,8 @@ suite "Waku v2 Rest API - Admin":
       getRes.data.len() == 0
 
   asyncTest "Get filter data - filter not mounted":
-    let getRes = await client.getFilterSubscriptions()
-    
+    let getRes = await client.getFilterSubscriptionsFilterNotMounted()
+
     check:
-      getRes.status == 200
-      $getRes.contentType == $MIMETYPE_JSON
-      getRes.data.len() == 0
+      getRes.status == 400
+      getRes.data == "Error: Filter Protocol is not mounted to the node"

waku/waku_api/rest/admin/client.nim

@@ -37,3 +37,7 @@ proc postPeers*(body: seq[string]):
 proc getFilterSubscriptions*():
     RestResponse[seq[FilterSubscription]]
     {.rest, endpoint: "/admin/v1/filter/subscriptions", meth: HttpMethod.MethodGet.}
+
+proc getFilterSubscriptionsFilterNotMounted*():
+    RestResponse[string]
+    {.rest, endpoint: "/admin/v1/filter/subscriptions", meth: HttpMethod.MethodGet.}

waku/waku_api/rest/admin/handlers.nim

@@ -113,15 +113,17 @@ proc installAdminV1PostPeersHandler(router: var RestRouter, node: WakuNode) =
 
 proc installAdminV1GetFilterSubsHandler(router: var RestRouter, node: WakuNode) =
   router.api(MethodGet, ROUTE_ADMIN_V1_FILTER_SUBS) do () -> RestApiResponse:
-
+
+    if node.wakuFilter.isNil():
+      return RestApiResponse.badRequest("Error: Filter Protocol is not mounted to the node")
+
     var subscriptions: seq[FilterSubscription] = @[]
 
     if not node.wakuFilter.isNil():
 
       var filterCriteria: seq[FilterTopic]
 
       for (peerId, criteria) in node.wakuFilter.subscriptions.pairs():
-
         filterCriteria = criteria.toSeq().mapIt(FilterTopic(pubsubTopic: it[0],
           contentTopic: it[1]))