add message and comment

comment/views/oj.py

@@ -0,0 +1,64 @@
+from django.db.models import Avg
+from comment.models import Comment
+from problem.models import Problem
+from utils.api import APIView
+from account.decorators import login_required
+from utils.api.api import validate_serializer
+from comment.serializers import CreateCommentSerializer
+from submission.models import Submission, JudgeStatus
+
+
+class CommentAPI(APIView):
+    @validate_serializer(CreateCommentSerializer)
+    @login_required
+    def post(self, request):
+        data = request.data
+        try:
+            problem = Problem.objects.get(id=data.problem_id, visible=True)
+        except Problem.DoesNotExist:
+            self.error("problem is not exists")
+
+        submission = None
+        if data.problem_solved and data.submission_id:
+            try:
+                data.submission_id
+                submission = Submission.objects.select_related("problem").get(
+                    id=data.submission_id,
+                    problem_id=data.problem_id,
+                    result=JudgeStatus.ACCEPTED,
+                )
+            except Submission.DoesNotExist:
+                self.error("submission is not exists or not accepted")
+
+        if not data.problem_solved:
+            data.language = None
+
+        Comment.objects.create(
+            user=request.user,
+            problem=problem,
+            submission=submission,
+            problem_solved=data.problem_solved,
+            language=data.language,
+            description_rating=data.description_rating,
+            difficulty_rating=data.difficulty_rating,
+            comprehensive_rating=data.comprehensive_rating,
+            content=data.content,
+        )
+        return self.success()
+
+    def get(self, request):
+        problem_id = request.GET.get("problem_id")
+        comments = Comment.objects.select_related("problem").filter(
+            problem_id=problem_id, visible=True
+        )
+        if comments.count() == 0:
+            return self.success()
+        rating = comments.aggregate(
+            description=Avg("description_rating"),
+            difficulty=Avg("difficulty_rating"),
+            comprehensive=Avg("comprehensive_rating"),
+        )
+        contents = comments.filter(content__isnull=False).values_list(
+            "content", flat=True
+        )
+        return self.success({rating: rating, contents: contents})