fix(browse-contributors-subjects): Fix title count when on central te…

…nant (#576)

- Count only shared instances for subject/contributor when on central tenant

Closes: MSEARCH-745
(cherry picked from commit 7b4d410)

src/main/java/org/folio/search/service/consortium/ConsortiumSearchHelper.java

@@ -102,8 +102,12 @@ public <T> Set<InstanceSubResource> filterSubResourcesForConsortium(
     var subResources = subResourceExtractor.apply(resource);
     var contextTenantId = folioExecutionContext.getTenantId();
     var centralTenantId = consortiumTenantService.getCentralTenant(contextTenantId);
-    if (centralTenantId.isEmpty() || contextTenantId.equals(centralTenantId.get())) {
+    if (centralTenantId.isEmpty()) {
       return subResources;
+    } else if (contextTenantId.equals(centralTenantId.get())) {
+      return subResources.stream()
+        .filter(InstanceSubResource::getShared)
+        .collect(Collectors.toSet());
     }
 
     var sharedFilter = getBrowseSharedFilter(context);

src/test/java/org/folio/search/service/consortium/ConsortiumSearchHelperTest.java

@@ -262,6 +262,21 @@ void filterSubResourcesForConsortium_positive_notConsortiumTenant() {
     assertThat(actual).isEqualTo(resource.getInstances());
   }
 
+  @Test
+  void filterSubResourcesForConsortium_positive_centralTenant() {
+    when(context.getTenantId()).thenReturn(CENTRAL_TENANT_ID);
+    when(tenantService.getCentralTenant(CENTRAL_TENANT_ID)).thenReturn(Optional.of(CENTRAL_TENANT_ID));
+
+    var browseContext = browseContext(null, null);
+    var resource = new SubjectResource();
+    resource.setInstances(subResources());
+
+    var actual = consortiumSearchHelper.filterSubResourcesForConsortium(browseContext, resource,
+      SubjectResource::getInstances);
+
+    assertThat(actual).hasSize(2);
+  }
+
   @Test
   void filterSubResourcesForConsortium_positive_memberTenant() {
     when(context.getTenantId()).thenReturn(TENANT_ID);