only add node if it doesn't already exist

doc/web/quickstart.rst

@@ -6,6 +6,8 @@ Web Support Quick Start
 Building Documentation Data
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
+New Test p
+
 To make use of the web support package in your application you'll
 need to build the data it uses. This data includes pickle files representing
 documents, search indices, and node data that is used to track where

sphinx/websupport/storage/__init__.py

@@ -16,6 +16,13 @@ class StorageBackend(object):
         """
         pass
 
+    def has_node(self, id):
+        """Check to see if a node exists.
+
+        :param id: the id to check for.
+        """
+        raise NotImplementedError()
+
     def add_node(self, id, document, source):
         """Add a node to the StorageBackend.
 

sphinx/websupport/storage/sqlalchemystorage.py

@@ -33,11 +33,16 @@ class SQLAlchemyStorage(StorageBackend):
     def pre_build(self):
         self.build_session = Session()
 
+    def has_node(self, id):
+        session = Session()
+        node = session.query(Node).filter(Node.id == id).first()
+        session.close()
+        return True if node else False
+
     def add_node(self, id, document, source):
         node = Node(id, document, source)
         self.build_session.add(node)
         self.build_session.flush()
-        return node
 
     def post_build(self):
         self.build_session.commit()

sphinx/writers/websupport.py

@@ -27,19 +27,19 @@ class WebSupportTranslator(HTMLTranslator):
         HTMLTranslator.dispatch_visit(self, node)
 
     def handle_visit_commentable(self, node):
-        db_node = self.add_db_node(node)
         # We will place the node in the HTML id attribute. If the node
         # already has an id (for indexing purposes) put an empty
         # span with the existing id directly before this node's HTML.
+        self.add_db_node(node)
         if node.attributes['ids']:
             self.body.append('<span id="%s"></span>'
                              % node.attributes['ids'][0])
-        node.attributes['ids'] = ['s%s' % db_node.id]
+        node.attributes['ids'] = ['s%s' % node.uid]
         node.attributes['classes'].append(self.comment_class)
 
     def add_db_node(self, node):
         storage = self.builder.app.storage
-        db_node_id = storage.add_node(id=node.uid,
-                                      document=self.builder.cur_docname,
-                                      source=node.rawsource or node.astext())
-        return db_node_id
+        if not storage.has_node(node.uid):
+            storage.add_node(id=node.uid,
+                             document=self.builder.cur_docname,
+                             source=node.rawsource or node.astext())