🎨 add halo version to database

src/main/java/cc/ryanc/halo/listener/StartedListener.java

@@ -1,7 +1,7 @@
 package cc.ryanc.halo.listener;
 
-import cc.ryanc.halo.model.support.Theme;
 import cc.ryanc.halo.model.enums.BlogPropertiesEnum;
+import cc.ryanc.halo.model.support.Theme;
 import cc.ryanc.halo.service.OptionsService;
 import cc.ryanc.halo.utils.HaloUtils;
 import cc.ryanc.halo.web.controller.core.BaseController;
@@ -39,6 +39,8 @@ public class StartedListener implements ApplicationListener<ApplicationStartedEv
 
     @Override
     public void onApplicationEvent(ApplicationStartedEvent event) {
+        // save halo version to database
+        optionsService.saveOption("version", HALO_VERSION);
         try {
             this.loadActiveTheme();
         } catch (TemplateModelException e) {

src/main/java/cc/ryanc/halo/model/support/HaloConst.java

@@ -15,6 +15,11 @@ import java.util.Map;
  */
 public class HaloConst {
 
+    /**
+     * version constant
+     */
+    public static final String HALO_VERSION = "0.4.2";
+
     /**
      * 所有设置选项（key,value）
      */

src/main/resources/templates/admin/module/_footer.ftl

@@ -1,5 +1,5 @@
 <footer class="main-footer">
     <#-- 虽然Halo使用了宽松的GPL协议，但开发不易，希望您可以保留一下版权声明。笔芯~ -->
-    <div class="pull-right hidden-xs"><a target="_blank" href="https://github.com/ruibaby/halo/releases/tag/v0.4.2">0.4.2</a></div>
+    <div class="pull-right hidden-xs"><a target="_blank" href="https://github.com/ruibaby/halo/releases/tag/v${options.version!}">${options.version!}</a></div>
     Thanks for using <strong><a data-pjax="true" href="/admin/halo">Halo</a>.</strong>
 </footer>