Update schema

schema.graphql

@@ -151,6 +151,17 @@ type AnswerNodeEdge {
   cursor: String!
 }
 
+input ApplySnapshotInput {
+  snapshot: ID!
+  selectedClass: ID!
+  clientMutationId: String
+}
+
+type ApplySnapshotPayload {
+  success: Boolean
+  clientMutationId: String
+}
+
 input AssignmentInput {
   id: ID!
   answer: String!
@@ -208,10 +219,11 @@ type ChapterBookmarkNodeEdge {
 }
 
 interface ChapterInterface {
+  id: ID!
   contentBlocks(offset: Int, before: String, after: String, first: Int, last: Int, slug: String, title: String): ContentBlockNodeConnection
 }
 
-type ChapterNode implements Node & ChapterInterface {
+type ChapterNode implements ChapterInterface {
   title: String!
   slug: String!
   description: String!
@@ -334,7 +346,7 @@ type CreateSchoolClassPayload {
 }
 
 input CreateSnapshotInput {
-  module: ID!
+  module: String!
   selectedClass: ID!
   clientMutationId: String
 }
@@ -407,6 +419,7 @@ type CustomMutation {
   updateChapterVisibility(input: UpdateChapterVisibilityInput!): UpdateChapterVisibilityPayload
   syncModuleVisibility(input: SyncModuleVisibilityInput!): SyncModuleVisibilityPayload
   createSnapshot(input: CreateSnapshotInput!): CreateSnapshotPayload
+  applySnapshot(input: ApplySnapshotInput!): ApplySnapshotPayload
   _debug: DjangoDebug
 }
 
@@ -623,10 +636,11 @@ type ModuleEdge {
 }
 
 interface ModuleInterface {
+  id: ID!
   pk: Int
 }
 
-type ModuleNode implements Node & ModuleInterface {
+type ModuleNode implements ModuleInterface {
   title: String!
   slug: String!
   metaTitle: String!
@@ -645,6 +659,7 @@ type ModuleNode implements Node & ModuleInterface {
   myAnswers(offset: Int, before: String, after: String, first: Int, last: Int): AnswerNodeConnection
   myContentBookmarks(offset: Int, before: String, after: String, first: Int, last: Int): ContentBlockBookmarkNodeConnection
   myChapterBookmarks(offset: Int, before: String, after: String, first: Int, last: Int): ChapterBookmarkNodeConnection
+  snapshots: [SnapshotNode]
 }
 
 type ModuleNodeConnection {
@@ -865,7 +880,7 @@ type SchoolClassNodeEdge {
   cursor: String!
 }
 
-type SnapshotChapterNode implements Node & ChapterInterface {
+type SnapshotChapterNode implements ChapterInterface {
   id: ID!
   chapter: ChapterNode!
   snapshot: SnapshotNode!
@@ -892,6 +907,7 @@ type SnapshotNode implements Node {
   chapters(offset: Int, before: String, after: String, first: Int, last: Int, id: ID): SnapshotChapterNodeConnection
   hiddenContentBlocks(offset: Int, before: String, after: String, first: Int, last: Int, slug: String, title: String): ContentBlockNodeConnection!
   chapterSnapshots(offset: Int, before: String, after: String, first: Int, last: Int, id: ID): SnapshotChapterNodeConnection!
+  title: String
 }
 
 input SpellCheckInput {