Disallow to return some settings that aren't in theme configuration

src/main/java/run/halo/app/event/LogEvent.java

@@ -0,0 +1,19 @@
+package run.halo.app.event;
+
+import org.springframework.context.ApplicationEvent;
+
+/**
+ * @author johnniang
+ * @date 19-4-20
+ */
+public class LogEvent extends ApplicationEvent {
+
+    /**
+     * Create a new ApplicationEvent.
+     *
+     * @param source the object on which the event initially occurred (never {@code null})
+     */
+    public LogEvent(Object source) {
+        super(source);
+    }
+}

src/main/java/run/halo/app/service/impl/ThemeSettingServiceImpl.java

@@ -115,19 +115,17 @@ public class ThemeSettingServiceImpl extends AbstractCrudService<ThemeSetting, I
 
         // Build settings from user-defined
         themeSettings.forEach(themeSetting -> {
-            Item item = itemMap.get(themeSetting.getKey());
-
-
-            // Convert data to corresponding data type
             String key = themeSetting.getKey();
 
-            Object convertedValue = themeSetting.getValue();
+            Item item = itemMap.get(key);
 
-            if (item != null) {
+            if (item == null) {
-                convertedValue = item.getDataType().convertTo(themeSetting.getValue());
+                return;
-                log.debug("Converted user-defined data from [{}] to [{}], type: [{}]", themeSetting.getValue(), convertedValue, item.getDataType());
             }
 
+            Object convertedValue = item.getDataType().convertTo(themeSetting.getValue());
+            log.debug("Converted user-defined data from [{}] to [{}], type: [{}]", themeSetting.getValue(), convertedValue, item.getDataType());
+
             result.put(key, convertedValue);
         });