Implement chapters / content blocks graphql interface

client/src/graphql/gql/moduleDetailsQuery.gql

@@ -24,6 +24,23 @@ query ModulesQuery($slug: String!) {
             }
           }
         }
+        chapters {
+          edges {
+            node {
+              id
+              contentBlocks {
+                edges {
+                  node {
+                    id
+                    slug
+                    title
+                    type
+                  }
+                }
+              }
+            }
+          }
+        }
       }
     }
   }

server/book/models/chapter.py

@@ -30,6 +30,9 @@ class Chapter(Page):
     parent_page_types = ['book.Module']
     subpage_types = ['book.ContentBlock']
 
+    def get_child_ids(self):
+        return self.get_children().values_list('id', flat=True)
+
     @classmethod
     def get_module_chapters(cls, module):
         return cls.objects.filter(id__in=module.get_child_ids()).live()

server/book/models/module.py

@@ -55,6 +55,9 @@ class Module(Page):
     parent_page_types = ['book.Topic']
     subpage_types = ['book.Chapter']
 
+    def get_child_ids(self):
+        return self.get_children().values_list('id', flat=True)
+
     @classmethod
     def get_topic_modules(cls, topic):
         return cls.objects.filter(id__in=topic.get_child_ids()).live()

server/book/schema.py

@@ -3,11 +3,41 @@ from graphene import relay
 from graphene_django import DjangoObjectType
 from graphene_django.filter import DjangoFilterConnectionField
 
-from .models import Book, Topic, Module
+from .models import Book, Topic, Module, Chapter, ContentBlock
+
+
+class ContentBlockNode(DjangoObjectType):
+    class Meta:
+        model = ContentBlock
+        only_fields = [
+            'slug', 'title', 'type'
+        ]
+        filter_fields = [
+            'slug', 'title',
+        ]
+        interfaces = (relay.Node,)
+
+
+class ChapterNode(DjangoObjectType):
+    content_blocks = DjangoFilterConnectionField(ContentBlockNode)
+
+    class Meta:
+        model = Chapter
+        only_fields = [
+            'slug', 'title',
+        ]
+        filter_fields = [
+            'slug', 'title',
+        ]
+        interfaces = (relay.Node,)
+
+    def resolve_content_blocks(self, *args, **kwargs):
+        return ContentBlock.get_chapter_content_blocks(self)
 
 
 class ModuleNode(DjangoObjectType):
     pk = graphene.Int()
+    chapters = DjangoFilterConnectionField(ChapterNode)
     hero_image = graphene.String()
 
     class Meta:
@@ -28,6 +58,9 @@ class ModuleNode(DjangoObjectType):
         if self.hero_image:
             return self.hero_image.file.url
 
+    def resolve_chapters(self, *args, **kwargs):
+        return Chapter.get_module_chapters(self)
+
 
 class TopicNode(DjangoObjectType):
     pk = graphene.Int()