Merge pull request #1305 from datacite/facet-behavior-tweak

Returns no facets when the result set is empty

app/controllers/datacite_dois_controller.rb

@@ -253,12 +253,14 @@ def index
         }
 
         aggregations = response.aggregations
-        facets = facets_to_facet_methods.map do |facet, method|
-          if aggregations.dig(facet)
-            buckets = facets_to_bucket_path.dig(facet) ? aggregations.dig(facet, *facets_to_bucket_path[facet]) : aggregations.dig(facet).buckets
-            [facet.to_s.camelize(:lower), send(method, buckets)]
-          end
-        end.compact.to_h
+        facets = total == 0 ? {} :
+          facets_to_facet_methods.map do |facet, method|
+            if aggregations.dig(facet)
+              buckets = facets_to_bucket_path.dig(facet) ? aggregations.dig(facet, *facets_to_bucket_path[facet]) : aggregations.dig(facet).buckets
+              [facet.to_s.camelize(:lower), send(method, buckets)]
+            end
+          end.compact.to_h
+
         respond_to do |format|
           format.json do
             options = {}

spec/requests/datacite_dois/datacite_dois_spec.rb

@@ -34,6 +34,12 @@ def clear_doi_index
   "downloads"
 ]
 
+DEFAULT_META_FIELDS = [
+  "total",
+  "totalPages",
+  "page",
+]
+
 describe DataciteDoisController, type: :request, vcr: true do
   let(:admin) { create(:provider, symbol: "ADMIN") }
   let(:admin_bearer) { Client.generate_token(role_id: "staff_admin", uid: admin.symbol, password: admin.password) }
@@ -265,7 +271,7 @@ def clear_doi_index
       expect(json.dig("meta", "total")).to eq(10)
 
       expect(json.dig("meta").length).to eq(DEFAULT_DOIS_FACETS.length + 3)
-      expect(json.dig("meta").keys).to match_array(DEFAULT_DOIS_FACETS + ["total", "totalPages", "page"])
+      expect(json.dig("meta").keys).to match_array(DEFAULT_DOIS_FACETS + DEFAULT_META_FIELDS)
     end
 
     it "returns default facets when disable-facets is set to false" do
@@ -276,7 +282,7 @@ def clear_doi_index
       expect(json.dig("meta", "total")).to eq(10)
 
       expect(json.dig("meta").length).to eq(DEFAULT_DOIS_FACETS.length + 3)
-      expect(json.dig("meta").keys).to match_array(DEFAULT_DOIS_FACETS + ["total", "totalPages", "page"])
+      expect(json.dig("meta").keys).to match_array(DEFAULT_DOIS_FACETS + DEFAULT_META_FIELDS)
     end
 
     it "returns no facets when disable-facets is set to true" do
@@ -319,6 +325,16 @@ def clear_doi_index
       expect(json.dig("meta", "madeUpFacet")).to eq(nil)
       expect(json.dig("meta", "made_up_facet")).to eq(nil)
     end
+
+    it "returns no facets when the result set is empty" do
+      get "/dois?query=creators.name:foo", nil, headers
+
+      expect(last_response.status).to eq(200)
+      expect(json["data"].size).to eq(0)
+      expect(json.dig("meta", "total")).to eq(0)
+      expect(json.dig("meta").length).to eq(3)
+      expect(json.dig("meta").keys).to match_array(DEFAULT_META_FIELDS)
+    end
   end
 
   describe "GET /dois with nil publisher values", elsasticsearch: true, prefix_pool_size: 1 do