BE: #1332 fixed schema name sorting

Author: germanosin

api/src/main/java/io/kafbat/ui/controller/SchemasController.java

@@ -245,11 +245,15 @@ public Mono<ResponseEntity<SchemaSubjectsResponseDTO>> getSchemas(String cluster
 
           List<String> subjectsToRetrieve;
           boolean paginate = true;
+
           var schemaComparator = Optional.ofNullable(orderBy).map(this::getComparatorForSchema);
-          final Optional<Comparator<SubjectWithCompatibilityLevel>> comparator =
-              sortOrder == null || !sortOrder.equals(SortOrderDTO.DESC)
-                  ? schemaComparator : schemaComparator.map(Comparator::reversed);
+          var comparator = sortOrder == null || !sortOrder.equals(SortOrderDTO.DESC)
+              ? schemaComparator : schemaComparator.map(Comparator::reversed);
+
           if (orderBy == null || SchemaColumnsToSortDTO.SUBJECT.equals(orderBy)) {
+            if (orderBy != null) {
+              filteredSubjects.sort(Comparator.nullsFirst(Comparator.naturalOrder()));
+            }
             if (SortOrderDTO.DESC.equals(sortOrder)) {
               filteredSubjects.sort(Comparator.nullsFirst(Comparator.reverseOrder()));
             }

api/src/test/java/io/kafbat/ui/service/SchemaRegistryPaginationTest.java

@@ -79,7 +79,7 @@ void shouldListFirst25andThen10Schemas() {
                     .toList()
     );
     var schemasFirst25 = controller.getSchemas(LOCAL_KAFKA_CLUSTER_NAME,
-            null, null, null, null, null, null, null).block();
+            null, null, null, SchemaColumnsToSortDTO.SUBJECT, null, null, null).block();
     assertThat(schemasFirst25).isNotNull();
     assertThat(schemasFirst25.getBody()).isNotNull();
     assertThat(schemasFirst25.getBody().getPageCount()).isEqualTo(4);
@@ -88,7 +88,7 @@ void shouldListFirst25andThen10Schemas() {
             .isSortedAccordingTo(Comparator.comparing(SchemaSubjectDTO::getSubject));
 
     var schemasFirst10 = controller.getSchemas(LOCAL_KAFKA_CLUSTER_NAME,
-            null, 10, null, null, null, null, null).block();
+            null, 10, null, SchemaColumnsToSortDTO.SUBJECT, null, null, null).block();
 
     assertThat(schemasFirst10).isNotNull();
     assertThat(schemasFirst10.getBody()).isNotNull();
@@ -123,7 +123,7 @@ void shouldCorrectlyHandleNonPositivePageNumberAndPageSize() {
                         .toList()
     );
     var schemas = controller.getSchemas(LOCAL_KAFKA_CLUSTER_NAME,
-            0, -1, null, null, null, null, null).block();
+            0, -1, null, SchemaColumnsToSortDTO.SUBJECT, null, null, null).block();
 
     assertThat(schemas).isNotNull();
     assertThat(schemas.getBody()).isNotNull();
@@ -142,7 +142,7 @@ void shouldCalculateCorrectPageCountForNonDivisiblePageSize() {
     );
 
     var schemas = controller.getSchemas(LOCAL_KAFKA_CLUSTER_NAME,
-            4, 33, null, null, null, null, null).block();
+            4, 33, null, SchemaColumnsToSortDTO.SUBJECT, null, null, null).block();
 
     assertThat(schemas).isNotNull();
     assertThat(schemas.getBody()).isNotNull();