Feat/dify rag (#2528)

Co-authored-by: jyong <jyong@dify.ai>

api/models/dataset.py

@@ -94,6 +94,14 @@ class Dataset(db.Model):
         return Document.query.with_entities(func.coalesce(func.sum(Document.word_count))) \
             .filter(Document.dataset_id == self.id).scalar()
 
+    @property
+    def doc_form(self):
+        document = db.session.query(Document).filter(
+            Document.dataset_id == self.id).first()
+        if document:
+            return document.doc_form
+        return None
+
     @property
     def retrieval_model_dict(self):
         default_retrieval_model = {