finish postTagService and test, modify sth in postService

Change-Id: I76b5982f578b5bffe3c48b0afeda219e01307455
diff --git a/src/main/java/com/example/g8backend/controller/PostController.java b/src/main/java/com/example/g8backend/controller/PostController.java
index 3557af2..f373539 100644
--- a/src/main/java/com/example/g8backend/controller/PostController.java
+++ b/src/main/java/com/example/g8backend/controller/PostController.java
@@ -1,5 +1,6 @@
 package com.example.g8backend.controller;
 
+import com.example.g8backend.dto.PostCreateDTO;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.http.ResponseEntity;
 import org.springframework.security.core.Authentication;
@@ -17,11 +18,18 @@
     private IPostService postService;
 
     @PostMapping("")
-    public ResponseEntity<?> createPost(@RequestBody Post post) {
+    public ResponseEntity<?> createPost(@RequestBody PostCreateDTO postCreateDTO) {
         Authentication authentication = SecurityContextHolder.getContext().getAuthentication();
         long userId = (long) authentication.getPrincipal();
+        Post post = postCreateDTO.getPost();
+        Long[] tagIds = postCreateDTO.getTagIds();
+
         post.setUserId(userId);
-        postService.save(post);
+        if (tagIds.length > 0){
+            postService.createPost(post, tagIds);
+        } else {
+            postService.createPost(post);
+        }
         return ResponseEntity.ok().build();
     }