fix(chunks): set position on remaining chunk insert paths

document_converters, the github size-fallback chunker, revert_service
restores, and the kb-persistence middleware now write explicit positions
(the middleware read path also orders by position).

surfsense_backend/app/agents/chat/multi_agent_chat/main_agent/middleware/kb_persistence/middleware.py

@@ -241,8 +241,15 @@ async def _create_document(
         chunk_embeddings = await asyncio.to_thread(embed_texts, chunks)
         session.add_all(
             [
-                Chunk(document_id=doc.id, content=text, embedding=embedding)
+                Chunk(
-                for text, embedding in zip(chunks, chunk_embeddings, strict=True)
+                    document_id=doc.id,
+                    content=text,
+                    embedding=embedding,
+                    position=i,
+                )
+                for i, (text, embedding) in enumerate(
+                    zip(chunks, chunk_embeddings, strict=True)
+                )
             ]
         )
     return doc
@@ -289,8 +296,15 @@ async def _update_document(
         chunk_embeddings = await asyncio.to_thread(embed_texts, chunks)
         session.add_all(
             [
-                Chunk(document_id=document.id, content=text, embedding=embedding)
+                Chunk(
-                for text, embedding in zip(chunks, chunk_embeddings, strict=True)
+                    document_id=document.id,
+                    content=text,
+                    embedding=embedding,
+                    position=i,
+                )
+                for i, (text, embedding) in enumerate(
+                    zip(chunks, chunk_embeddings, strict=True)
+                )
             ]
         )
     return document
@@ -475,7 +489,9 @@ async def _load_chunks_for_snapshot(
     session: AsyncSession, *, doc_id: int
 ) -> list[dict[str, str]]:
     rows = await session.execute(
-        select(Chunk.content).where(Chunk.document_id == doc_id).order_by(Chunk.id)
+        select(Chunk.content)
+        .where(Chunk.document_id == doc_id)
+        .order_by(Chunk.position, Chunk.id)
     )
     return [{"content": row.content} for row in rows.all() if row.content is not None]
 

surfsense_backend/app/services/revert_service.py

@@ -238,9 +238,14 @@ async def _restore_in_place_document(
             chunk_embeddings = await asyncio.to_thread(embed_texts, chunk_texts)
             session.add_all(
                 [
-                    Chunk(document_id=doc.id, content=text, embedding=embedding)
+                    Chunk(
-                    for text, embedding in zip(
+                        document_id=doc.id,
-                        chunk_texts, chunk_embeddings, strict=True
+                        content=text,
+                        embedding=embedding,
+                        position=i,
+                    )
+                    for i, (text, embedding) in enumerate(
+                        zip(chunk_texts, chunk_embeddings, strict=True)
                     )
                 ]
             )
@@ -336,8 +341,15 @@ async def _reinsert_document_from_revision(
         chunk_embeddings = await asyncio.to_thread(embed_texts, chunk_texts)
         session.add_all(
             [
-                Chunk(document_id=new_doc.id, content=text, embedding=embedding)
+                Chunk(
-                for text, embedding in zip(chunk_texts, chunk_embeddings, strict=True)
+                    document_id=new_doc.id,
+                    content=text,
+                    embedding=embedding,
+                    position=i,
+                )
+                for i, (text, embedding) in enumerate(
+                    zip(chunk_texts, chunk_embeddings, strict=True)
+                )
             ]
         )
 

surfsense_backend/app/tasks/connector_indexers/github_indexer.py

@@ -525,6 +525,7 @@ async def _simple_chunk_content(content: str, chunk_size: int = 4000) -> list:
                 Chunk(
                     content=chunk_text,
                     embedding=embed_text(chunk_text),
+                    position=len(chunks),
                 )
             )
 

surfsense_backend/app/utils/document_converters.py

@@ -188,8 +188,10 @@ async def create_document_chunks(content: str) -> list[Chunk]:
     chunk_texts = [c.text for c in config.chunker_instance.chunk(content)]
     chunk_embeddings = await asyncio.to_thread(embed_texts, chunk_texts)
     return [
-        Chunk(content=text, embedding=emb)
+        Chunk(content=text, embedding=emb, position=i)
-        for text, emb in zip(chunk_texts, chunk_embeddings, strict=False)
+        for i, (text, emb) in enumerate(
+            zip(chunk_texts, chunk_embeddings, strict=False)
+        )
     ]