RWA-4594: Refactor DmnEvaluationService

src/main/java/uk/gov/hmcts/reform/wataskmanagementapi/services/DmnEvaluationService.java

@@ -25,6 +25,7 @@
 import static uk.gov.hmcts.reform.wataskmanagementapi.domain.DecisionTable.WA_TASK_CONFIGURATION;
 import static uk.gov.hmcts.reform.wataskmanagementapi.domain.DecisionTable.WA_TASK_PERMISSIONS;
 import static uk.gov.hmcts.reform.wataskmanagementapi.domain.camunda.CamundaValue.jsonValue;
+import static uk.gov.hmcts.reform.wataskmanagementapi.services.utils.DmnConfigFieldUtils.cleanFieldsWithInternalDefaults;
 
 @Slf4j
 @Component
@@ -108,21 +109,7 @@ private List<ConfigurationDmnEvaluationResponse> performEvaluateConfigurationDmn
                 new DmnRequest<>(new DecisionTableRequest(jsonValue(caseData), jsonValue(taskAttributes)))
             );
 
-            /**
-             * Loop through each field in dmnConfigFieldsWithInternalDefaults and check if the field is equal to the
-             * name from dmnResponse. If the name is present, then get the value of the field. Check if the value is
-             * null or empty for that field if yes then remove the field from the dmnResponse so that it won't override
-             * existing value.
-             */
-
-            dmnConfigFieldsWithInternalDefaults.forEach(
-                field ->
-                    dmnResponse.removeIf(response -> {
-                        String nameValue = response.getName().getValue();
-                        String responseValue = response.getValue() != null ? response.getValue().getValue() : null;
-                        return field.equals(nameValue) && (responseValue == null || responseValue.isEmpty());
-                    })
-            );
+            cleanFieldsWithInternalDefaults(dmnConfigFieldsWithInternalDefaults, dmnResponse);
 
             return dmnResponse.stream().map(response -> {
                 if (fieldsToExcludeFromTrim.contains(response.getName().getValue())) {

src/main/java/uk/gov/hmcts/reform/wataskmanagementapi/services/utils/DmnConfigFieldUtils.java

@@ -0,0 +1,34 @@
+package uk.gov.hmcts.reform.wataskmanagementapi.services.utils;
+
+import uk.gov.hmcts.reform.wataskmanagementapi.domain.camunda.ConfigurationDmnEvaluationResponse;
+
+import java.util.List;
+
+public class DmnConfigFieldUtils {
+
+    private DmnConfigFieldUtils() {
+
+    }
+
+    public static void cleanFieldsWithInternalDefaults(
+        List<String> dmnConfigFieldsWithInternalDefaults,
+        List<ConfigurationDmnEvaluationResponse> dmnResponse
+    ) {
+
+        /**
+         * Loop through each field in dmnConfigFieldsWithInternalDefaults and check if the field is equal to the
+         * name from dmnResponse. If the name is present, then get the value of the field. Check if the value is
+         * null or empty for that field if yes then remove the field from the dmnResponse so that it won't override
+         * existing value.
+         */
+
+        dmnConfigFieldsWithInternalDefaults.forEach(
+            field ->
+                dmnResponse.removeIf(response -> {
+                    String nameValue = response.getName().getValue();
+                    String responseValue = response.getValue() != null ? response.getValue().getValue() : null;
+                    return field.equals(nameValue) && (responseValue == null || responseValue.isEmpty());
+                })
+        );
+    }
+}

src/test/java/uk/gov/hmcts/reform/wataskmanagementapi/services/utils/DmnConfigFieldUtilTest.java

@@ -0,0 +1,63 @@
+package uk.gov.hmcts.reform.wataskmanagementapi.services.utils;
+
+import org.junit.jupiter.api.Test;
+import uk.gov.hmcts.reform.wataskmanagementapi.domain.camunda.CamundaValue;
+import uk.gov.hmcts.reform.wataskmanagementapi.domain.camunda.ConfigurationDmnEvaluationResponse;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+
+class DmnConfigFieldUtilTest {
+
+    @Test
+    void should_remove_field_with_null_value() {
+        List<ConfigurationDmnEvaluationResponse> responses = new ArrayList<>();
+        ConfigurationDmnEvaluationResponse configurationDmnEvaluationResponse =
+            new ConfigurationDmnEvaluationResponse();
+        configurationDmnEvaluationResponse.setName(new CamundaValue<>("field1", "String"));
+        configurationDmnEvaluationResponse.setValue(null);
+        responses.add(configurationDmnEvaluationResponse);
+        List<String> fields = List.of("field1");
+
+        DmnConfigFieldUtils.cleanFieldsWithInternalDefaults(fields, responses);
+
+        assertTrue(responses.isEmpty());
+    }
+
+    @Test
+    void should_remove_field_with_empty_value() {
+        List<ConfigurationDmnEvaluationResponse> responses = new ArrayList<>();
+        ConfigurationDmnEvaluationResponse configurationDmnEvaluationResponse =
+            new ConfigurationDmnEvaluationResponse();
+        configurationDmnEvaluationResponse.setName(new CamundaValue<>("field1", "String"));
+        configurationDmnEvaluationResponse.setValue(new CamundaValue<>("", "String"));
+        responses.add(configurationDmnEvaluationResponse);
+        List<String> fields = List.of("field1");
+
+        DmnConfigFieldUtils.cleanFieldsWithInternalDefaults(fields, responses);
+
+        assertTrue(responses.isEmpty());
+    }
+
+    @Test
+    void should_not_remove_field_with_non_empty_value() {
+        List<ConfigurationDmnEvaluationResponse> responses = new ArrayList<>();
+        ConfigurationDmnEvaluationResponse configurationDmnEvaluationResponse =
+            new ConfigurationDmnEvaluationResponse();
+        configurationDmnEvaluationResponse.setName(new CamundaValue<>("field1", "String"));
+        configurationDmnEvaluationResponse.setValue(new CamundaValue<>("someValue", "String"));
+        responses.add(configurationDmnEvaluationResponse);
+        List<String> fields = List.of("field1");
+
+        DmnConfigFieldUtils.cleanFieldsWithInternalDefaults(fields, responses);
+
+        assertFalse(responses.isEmpty());
+        assertEquals("someValue", responses.getFirst().getValue().getValue());
+    }
+
+}