bugfix: record empty commit when only modify item comment

apollo-adminservice/src/main/java/com/ctrip/framework/apollo/adminservice/controller/ItemController.java

@@ -90,14 +90,16 @@ public class ItemController {
     builder.updateItem(beforeUpdateItem, entity);
     itemDTO = BeanUtils.transfrom(ItemDTO.class, entity);
 
-    Commit commit = new Commit();
-    commit.setAppId(appId);
-    commit.setClusterName(clusterName);
-    commit.setNamespaceName(namespaceName);
-    commit.setChangeSets(builder.build());
-    commit.setDataChangeCreatedBy(itemDTO.getDataChangeLastModifiedBy());
-    commit.setDataChangeLastModifiedBy(itemDTO.getDataChangeLastModifiedBy());
-    commitService.save(commit);
+    if (builder.hasContent()) {
+      Commit commit = new Commit();
+      commit.setAppId(appId);
+      commit.setClusterName(clusterName);
+      commit.setNamespaceName(namespaceName);
+      commit.setChangeSets(builder.build());
+      commit.setDataChangeCreatedBy(itemDTO.getDataChangeLastModifiedBy());
+      commit.setDataChangeLastModifiedBy(itemDTO.getDataChangeLastModifiedBy());
+      commitService.save(commit);
+    }
 
     return itemDTO;
   }

apollo-biz/src/main/java/com/ctrip/framework/apollo/biz/entity/Commit.java

@@ -7,6 +7,7 @@ import org.hibernate.annotations.Where;
 
 import javax.persistence.Column;
 import javax.persistence.Entity;
+import javax.persistence.Lob;
 import javax.persistence.Table;
 
 @Entity
@@ -15,7 +16,8 @@ import javax.persistence.Table;
 @Where(clause = "isDeleted = 0")
 public class Commit extends BaseEntity {
 
-  @Column(name = "ChangeSets", length = 4048, nullable = false)
+  @Lob
+  @Column(name = "ChangeSets", nullable = false)
   private String changeSets;
 
   @Column(name = "AppId", nullable = false)