Update unit test and add mutation

server/api/types.py

@@ -3,3 +3,7 @@ import graphene
 
 class FailureNode(graphene.Interface):
     reason = graphene.String()
+
+
+class SuccessNode(graphene.Interface):
+    message = graphene.String()

server/books/schema/mutations/__init__.py

@@ -1,7 +1,7 @@
 from books.schema.mutations.chapter import UpdateChapterVisibility
 from books.schema.mutations.contentblock import MutateContentBlock, AddContentBlock, DeleteContentBlock
 from books.schema.mutations.module import UpdateSolutionVisibility, UpdateLastModule, SyncModuleVisibility
-from books.schema.mutations.snapshot import CreateSnapshot, ApplySnapshot, ShareSnapshot, UpdateSnapshot
+from books.schema.mutations.snapshot import CreateSnapshot, ApplySnapshot, ShareSnapshot, UpdateSnapshot, DeleteSnapshot
 from books.schema.mutations.topic import UpdateLastTopic
 
 
@@ -18,3 +18,4 @@ class BookMutations(object):
     apply_snapshot = ApplySnapshot.Field()
     share_snapshot = ShareSnapshot.Field()
     update_snapshot = UpdateSnapshot.Field()
+    delete_snapshot = DeleteSnapshot.Field()

server/books/schema/mutations/snapshot.py

@@ -2,7 +2,7 @@ import graphene
 from django.db.models import Q
 from graphene import relay
 
-from api.types import FailureNode
+from api.types import FailureNode, SuccessNode
 from api.utils import get_object
 from books.models import Module, ContentBlock, Chapter
 from books.models.snapshot import Snapshot
@@ -15,7 +15,13 @@ class NotOwner(graphene.ObjectType):
         interfaces = (FailureNode,)
 
 
+class Success(graphene.ObjectType):
+    class Meta:
+        interfaces = (SuccessNode,)
+
+
 NotOwnerFailure = NotOwner(reason="Not the owner")
+DeleteSnapshotSuccess = Success(message='Snapshot deleted successfully')
 
 
 class UpdateSnapshotResult(graphene.Union):
@@ -23,6 +29,11 @@ class UpdateSnapshotResult(graphene.Union):
         types = (SnapshotNode, NotOwner,)
 
 
+class DeleteSnapshotResult(graphene.Union):
+    class Meta:
+        types = (Success, NotOwner,)
+
+
 class CreateSnapshot(relay.ClientIDMutation):
     class Input:
         module = graphene.String(required=True)
@@ -66,6 +77,25 @@ class UpdateSnapshot(relay.ClientIDMutation):
         return cls(snapshot=snapshot)
 
 
+class DeleteSnapshot(relay.ClientIDMutation):
+    class Input:
+        id = graphene.ID(required=True)
+
+    result = graphene.Field(DeleteSnapshotResult)
+
+    @classmethod
+    def mutate_and_get_payload(cls, root, info, **args):
+        id = args.get('id')
+        user = info.context.user
+
+        snapshot = get_object(Snapshot, id)
+        if snapshot.creator != user:
+            return cls(result=NotOwnerFailure)
+
+        snapshot.delete()
+        return cls(result=DeleteSnapshotResult)
+
+
 class ApplySnapshot(relay.ClientIDMutation):
     class Input:
         snapshot = graphene.ID(required=True)

server/books/tests/queries.py

@@ -152,3 +152,16 @@ mutation UpdateSnapshot($input: UpdateSnapshotInput!) {
   }
 }
 """
+
+DELETE_SNAPSHOT_MUTATION = """
+mutation DeleteSnapshot($id: ID!) { 
+  deleteSnapshot(id: $id) {
+    result {
+        success
+        ...on NotOwner {
+          reason
+        }
+    }
+  }
+}
+"""

server/books/tests/test_snapshots.py

@@ -7,7 +7,7 @@ from api.utils import get_object
 from books.factories import ModuleFactory, ChapterFactory, ContentBlockFactory
 from books.models import Snapshot, ChapterSnapshot
 from books.tests.queries import MODULE_QUERY, SNAPSHOT_MODULE_QUERY, CREATE_SNAPSHOT_MUTATION, APPLY_SNAPSHOT_MUTATION, \
-    MODULE_SNAPSHOTS_QUERY, SHARE_SNAPSHOT_MUTATION, UPDATE_SNAPSHOT_MUTATION
+    MODULE_SNAPSHOTS_QUERY, SHARE_SNAPSHOT_MUTATION, UPDATE_SNAPSHOT_MUTATION, DELETE_SNAPSHOT_MUTATION
 from core.tests.base_test import SkillboxTestCase
 from objectives.factories import ObjectiveGroupFactory, ObjectiveFactory
 from users.factories import SchoolClassFactory
@@ -425,7 +425,6 @@ class SnapshotTestCase(SkillboxTestCase):
         self.assertIsNone(result.errors)
         self.assertEqual(len(result.data.get('module').get('snapshots')), 1)
 
-
     def _setup_title_change(self):
         self.assertIsNone(self.snapshot.title)
         new_title = 'New Snapshot Title'
@@ -450,7 +449,13 @@ class SnapshotTestCase(SkillboxTestCase):
         self.assertEqual(result.data.get('updateSnapshot').get('snapshot').get('reason'), 'Not the owner')
 
     def test_delete_snapshot(self):
-        self.assertTrue(False)
+        result = self.get_client().execute(DELETE_SNAPSHOT_MUTATION, variables={
+            'input': {
+                'id': self.snapshot
+            }
+        })
+        self.assertIsNone(result.errors)
+        self.assertEqual(result.data.get('deleteSnapshot').get('result').get('__typename'), 'SuccessNode')
 
     def test_delete_snapshot_not_owner_fails(self):
         self.assertTrue(False)