From 1d5baece1e1244558882835dacafc1d7c8def8ac Mon Sep 17 00:00:00 2001
From: Tom Hacohen <tom@stosb.com>
Date: Tue, 4 Aug 2020 13:42:28 +0300
Subject: [PATCH] Chunk uploading: implement properly using a custom Parser.

---
 .../migrations/0022_auto_20200804_1059.py     | 17 ++++++++++++++
 django_etebase/models.py                      |  3 +++
 django_etebase/parsers.py                     | 15 +++++++++++++
 django_etebase/views.py                       | 22 ++++++++++++++-----
 4 files changed, 52 insertions(+), 5 deletions(-)
 create mode 100644 django_etebase/migrations/0022_auto_20200804_1059.py
 create mode 100644 django_etebase/parsers.py

diff --git a/django_etebase/migrations/0022_auto_20200804_1059.py b/django_etebase/migrations/0022_auto_20200804_1059.py
new file mode 100644
index 0000000..c47e562
--- /dev/null
+++ b/django_etebase/migrations/0022_auto_20200804_1059.py
@@ -0,0 +1,17 @@
+# Generated by Django 3.0.3 on 2020-08-04 10:59
+
+from django.db import migrations
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('django_etebase', '0021_auto_20200626_0913'),
+    ]
+
+    operations = [
+        migrations.AlterUniqueTogether(
+            name='collectionitemchunk',
+            unique_together={('item', 'uid')},
+        ),
+    ]
diff --git a/django_etebase/models.py b/django_etebase/models.py
index f3704a3..0c33301 100644
--- a/django_etebase/models.py
+++ b/django_etebase/models.py
@@ -100,6 +100,9 @@ class CollectionItemChunk(models.Model):
     def __str__(self):
         return self.uid
 
+    class Meta:
+        unique_together = ('item', 'uid')
+
 
 def generate_stoken_uid():
     return get_random_string(32, allowed_chars='abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789-_')
diff --git a/django_etebase/parsers.py b/django_etebase/parsers.py
new file mode 100644
index 0000000..1ca1a70
--- /dev/null
+++ b/django_etebase/parsers.py
@@ -0,0 +1,15 @@
+from rest_framework.parsers import FileUploadParser
+
+
+class ChunkUploadParser(FileUploadParser):
+    """
+    Parser for chunk upload data.
+    """
+    media_type = 'application/octet-stream'
+
+    def get_filename(self, stream, media_type, parser_context):
+        """
+        Detects the uploaded file name.
+        """
+        view = parser_context['view']
+        return parser_context['kwargs'][view.lookup_field]
diff --git a/django_etebase/views.py b/django_etebase/views.py
index eb04e4b..c299dc2 100644
--- a/django_etebase/views.py
+++ b/django_etebase/views.py
@@ -73,6 +73,7 @@ from .serializers import (
     )
 from .utils import get_user_queryset
 from .exceptions import EtebaseValidationError
+from .parsers import ChunkUploadParser
 
 User = get_user_model()
 
@@ -398,11 +399,11 @@ class CollectionItemViewSet(BaseViewSet):
 
 
 class CollectionItemChunkViewSet(viewsets.ViewSet):
-    allowed_methods = ['GET', 'POST']
+    allowed_methods = ['GET', 'PUT']
     authentication_classes = BaseViewSet.authentication_classes
     permission_classes = BaseViewSet.permission_classes
     renderer_classes = BaseViewSet.renderer_classes
-    parser_classes = (MultiPartParser, )
+    parser_classes = (ChunkUploadParser, )
     serializer_class = CollectionItemChunkSerializer
     lookup_field = 'uid'
 
@@ -413,13 +414,24 @@ class CollectionItemChunkViewSet(viewsets.ViewSet):
         user = self.request.user
         return queryset.filter(members__user=user)
 
-    def create(self, request, collection_uid=None, collection_item_uid=None, *args, **kwargs):
+    def update(self, request, *args, collection_uid=None, collection_item_uid=None, uid=None, **kwargs):
         col = get_object_or_404(self.get_collection_queryset(), main_item__uid=collection_uid)
         col_it = get_object_or_404(col.items, uid=collection_item_uid)
 
-        serializer = self.get_serializer_class()(data=request.data)
+        data = {
+            "uid": uid,
+            "chunkFile": request.data["file"],
+        }
+
+        serializer = self.get_serializer_class()(data=data)
         serializer.is_valid(raise_exception=True)
-        serializer.save(item=col_it)
+        try:
+            serializer.save(item=col_it)
+        except IntegrityError:
+            return Response(
+                {"code": "chunk_exists", "detail": "Chunk already exists."},
+                status=status.HTTP_409_CONFLICT
+            )
 
         return Response({}, status=status.HTTP_201_CREATED)