spring mvc : PRG(Post/Redirect/Get), RedirectAttribute

spring-mvc/item-service/src/main/java/com/example/itemservice/web/basic/BasicItemController.java

@@ -6,6 +6,7 @@ import lombok.RequiredArgsConstructor;
 import org.springframework.stereotype.Controller;
 import org.springframework.ui.Model;
 import org.springframework.web.bind.annotation.*;
+import org.springframework.web.servlet.mvc.support.RedirectAttributes;
 
 import javax.annotation.PostConstruct;
 import java.util.List;
@@ -66,12 +67,20 @@ public class BasicItemController {
         return "basic/item";
     }
 
-    @PostMapping("/add")
+//    @PostMapping("/add")
     public String addItemV4(Item item) {
         itemRepository.save(item);
         return "basic/item";
     }
 
+    @PostMapping("/add")
+    public String addItemV5(Item item, RedirectAttributes redirectAttributes) {
+        Item savedItem = itemRepository.save(item);
+        redirectAttributes.addAttribute("itemId", savedItem.getId());
+        redirectAttributes.addAttribute("status", true);
+        return "redirect:/basic/items/{itemId}";
+    }
+
     @GetMapping("/{itemId}/edit")
     public String editForm(@PathVariable Long itemId, Model model) {
         Item item = itemRepository.findById(itemId);

spring-mvc/item-service/src/main/resources/templates/basic/item.html

@@ -14,6 +14,9 @@
   <div class="py-5 text-center">
     <h2>상품 상세</h2>
   </div>
+
+  <h2 th:if="${param.status}" th:text="'저장 완료'"></h2>
+
   <div>
     <label for="itemId">상품 ID</label>
     <input type="text" id="itemId" name="itemId" class="form-control" th:value="${item.id}"