diff --git a/comments/api/tests.py b/comments/api/tests.py
index a2691e4..e80797c 100644
--- a/comments/api/tests.py
+++ b/comments/api/tests.py
@@ -101,3 +101,33 @@ def test_update(self):
         self.assertEqual(comment.created_at, before_created_at)
         self.assertNotEqual(comment.created_at, now)
         self.assertNotEqual(comment.updated_at, before_updated_at)
+
+    def test_list(self):
+        # must have tweet_id
+        response = self.anonymous_client.get(COMMENT_URL)
+        self.assertEqual(response.status_code, 400)
+
+        # you can visit with tweet_id
+        # but at the beginning, no comment
+        response = self.anonymous_client.get(
+            COMMENT_URL,
+            {'tweet_id' : self.tweet.id},
+        )
+        self.assertEqual(response.status_code, 200)
+        self.assertEqual(len(response.data['comments']), 0)
+
+        # comments order by time
+        self.create_comment(self.linghu, self.tweet, '1')
+        self.create_comment(self.dongxie, self.tweet, '2')
+        self.create_comment(self.dongxie, self.create_tweet(self.dongxie), '3')
+        response = self.anonymous_client.get(COMMENT_URL, {'tweet_id' : self.tweet.id})
+        self.assertEqual(len(response.data['comments']), 2)
+        self.assertEqual(response.data['comments'][0]['content'], '1')
+        self.assertEqual(response.data['comments'][1]['content'], '2')
+
+        #同时提供 userid 和 tweetid， 只有 tweetid 会在 filter 中生效
+        response = self.anonymous_client.get(COMMENT_URL, {
+            'tweet_id' : self.tweet.id,
+            'user_id' : self.linghu.id,
+        })
+        self.assertEqual(len(response.data['comments']), 2)
\ No newline at end of file
diff --git a/comments/api/views.py b/comments/api/views.py
index 92e1e68..0505fc9 100644
--- a/comments/api/views.py
+++ b/comments/api/views.py
@@ -13,9 +13,10 @@
 class CommentViewSet(viewsets.GenericViewSet):
     serializer_class = CommentSerializerForCreate
     queryset = Comment.objects.all()
+    filterset_fields = ('tweet_id',  )
 
     # POST /api/comments/ -> create
-    # GET /api/comments/ -> list
+    # GET /api/comments/?tweet_id= -> list
     # Get /api/comments/1/ -> retrieve
     # DELETE /api/comments/1/ -> destroy
     # PATCH /api/comments/1/ -> partial_update
@@ -28,6 +29,25 @@ def get_permissions(self):
             return [IsAuthenticated(), IsObjectOwner()]
         return [AllowAny()]
 
+    def list(self, request, *args, **kwargs):
+        if 'tweet_id' not in request.query_params:
+            return Response({
+                'message' : 'missing tweet_id in request',
+                'success' : False,
+            }, status=status.HTTP_400_BAD_REQUEST)
+        # 这种写法在后期需要添加其他属性进行筛选就很方便
+        queryset = self.get_queryset()
+        comments = self.filter_queryset(queryset)\
+            .prefetch_related('user')\
+            .order_by('created_at')
+        # tweet_id = request.query_params['tweet_id']
+        # comments = Comment.objects.filter(tweet_id=tweet_id)
+        serializer = CommentSerializer(comments, many=True)
+        return Response({
+            'comments' : serializer.data,
+        }, status=status.HTTP_200_OK)
+
+
 
     def create(self, request, *args, **kwargs):
         data = {
diff --git a/comments/models.py b/comments/models.py
index a8c6a84..6fa6988 100644
--- a/comments/models.py
+++ b/comments/models.py
@@ -6,7 +6,7 @@ class Comment(models.Model):
 
     user = models.ForeignKey(User, on_delete=models.SET_NULL, null=True)
     tweet = models.ForeignKey(Tweet, on_delete=models.SET_NULL, null=True)
-    content = models.CharField(max_length=140)
+    content = models.TextField(max_length=140)
     created_at = models.DateTimeField(auto_now_add=True)
     updated_at = models.DateTimeField(auto_now=True)
 
diff --git a/requirements.txt b/requirements.txt
index fcfd2c0..9e67f19 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -5,6 +5,7 @@ chardet==3.0.4
 cryptography==2.1.4
 Django==3.1.3
 django-debug-toolbar==3.2.4
+django-filter==21.1
 djangorestframework==3.12.2
 idna==2.6
 keyring==10.6.0
diff --git a/twitter/settings.py b/twitter/settings.py
index 651e9a5..787a555 100644
--- a/twitter/settings.py
+++ b/twitter/settings.py
@@ -40,6 +40,8 @@
     'django.contrib.staticfiles',
     # third party
     'rest_framework',
+    'debug_toolbar',
+    'django_filters',
 
     # project apps
     'accounts',
@@ -47,8 +49,7 @@
     'friendships',
     'newsfeeds',
     'comments',
-    # debug tool
-    'debug_toolbar',
+
 ]
 
 MIDDLEWARE = [
@@ -118,7 +119,10 @@
 
 REST_FRAMEWORK = {
     'DEFAULT_PAGINATION_CLASS': 'rest_framework.pagination.PageNumberPagination',
-    'PAGE_SIZE': 10
+    'PAGE_SIZE': 10,
+    'DEFAULT_FILTER_BACKENDS' : [
+        'django_filters.rest_framework.DjangoFilterBackend',
+    ],
 }
 
 
@@ -140,3 +144,8 @@
 # https://docs.djangoproject.com/en/3.1/howto/static-files/
 
 STATIC_URL = '/static/'
+
+try:
+    from .local_settings import *
+except:
+    pass