Create post paging function

post 목록의 paging 기능을 추가하였습니다.

@@ -6,13 +6,28 @@ var util = require('../util');
 
 
 // Post home
-router.get('/', function(req, res){
-    Post.find({})
-    .populate('author')
-    .sort('-createdAt')
-    .exec(function(err, posts){
-        if(err){return res.json(err)};
-        res.render('posts/index', {posts:posts});
+router.get('/', async function(req, res){
+    // Paging 기능 추가 
+    var page = Math.max(1, parseInt(req.query.page));   
+    var limit = Math.max(1, parseInt(req.query.limit)); 
+    page = !isNaN(page)?page:1;                         
+    limit = !isNaN(limit)?limit:10;                     
+  
+    var skip = (page-1)*limit; 
+    var count = await Post.countDocuments({}); 
+    var maxPage = Math.ceil(count/limit); 
+    var posts = await Post.find({}) 
+      .populate('author')
+      .sort('-createdAt')
+      .skip(skip)  
+      .limit(limit) 
+      .exec();
+  
+    res.render('posts/index', {
+      posts:posts,
+      currentPage:page, 
+      maxPage:maxPage,  
+      limit:limit       
     });
 });
 

@@ -47,15 +47,31 @@
               </tr>
             <% }) %>
           </tbody>
-  
         </table>
 
+        <nav class="nav justify-content-center bg-light">
+          <% 
+            var offset = 2;
+            var previousBtnEnabled = currentPage>1;
+            var nextBtnEnabled = currentPage<maxPage;
+          %>
+          <ul class="pagination pagination-sm justify-content-center align-items-center h-100 mb-0">            
+            <li class="page-item <%= previousBtnEnabled?'':'disabled' %>">
+              <a class="page-link" href="/posts?page=<%= currentPage-1 %>&limit=<%= limit %>"<%= previousBtnEnabled?'':'tabindex=-1' %>>«</a>
+            </li>
+            <% for(i=1;i<=maxPage;i++){ %>
+              <% if(i==1 || i==maxPage || (i>=currentPage-offset && i<=currentPage+offset)){ %>
+                <li class="page-item <%= currentPage==i?'active':'' %>"><a class="page-link" href="/posts?page=<%= i %>&limit=<%= limit %>"><%= i %></a></li>
+              <% } else if(i==2 || i==maxPage-1){ %>
+                <li><a class="page-link">...</a></li>
+              <% } %>
+            <% } %>
+            <li class="page-item <%= nextBtnEnabled?'':'disabled' %>">
+              <a class="page-link" href="/posts?page=<%= currentPage+1 %>&limit=<%= limit %>"<%= nextBtnEnabled?'':'tabindex=-1' %>>»</a>
+            </li>
+          </ul>
+        </nav>
       </div>
-
-     
-
-
-
     </div>
   </body>
 </html>
\ No newline at end of file