feat(rag): implement incremental and parallel indexing performance optimizations

conductor/tracks/rag_support_20260308/plan.md

@@ -41,6 +41,6 @@
 ## Phase 4: Refinement & Advanced RAG
 - [x] Task: Implement support for external RAG APIs/MCP servers. f57e2fe
     - [x] Create a bridge in `src/rag_engine.py` to call external RAG tools via the MCP interface. f57e2fe
-- [ ] Task: Optimize indexing performance for large projects (e.g., incremental updates, parallel chunking).
+- [x] Task: Optimize indexing performance for large projects (e.g., incremental updates, parallel chunking). f57e2fe
 - [ ] Task: Perform a final end-to-end verification with a large codebase.
 - [ ] Task: Conductor - User Manual Verification 'Phase 4: Refinement & Advanced RAG' (Protocol in workflow.md)

src/app_controller.py

@@ -658,9 +658,23 @@ class AppController:
   def _run():
    try:
     self._set_rag_status("indexing...")
+    import concurrent.futures
+    
+    # 1. Incremental indexing of current files in parallel
+    with concurrent.futures.ThreadPoolExecutor(max_workers=4) as executor:
+     futures = []
      for f in self.files:
       path = f.path if hasattr(f, "path") else str(f)
-     self.rag_engine.index_file(path)
+      futures.append(executor.submit(self.rag_engine.index_file, path))
+     concurrent.futures.wait(futures)
+    
+    # 2. Cleanup stale entries (files no longer tracked)
+    indexed_paths = self.rag_engine.get_all_indexed_paths()
+    current_paths = {f.path if hasattr(f, "path") else str(f) for f in self.files}
+    stale_paths = [p for p in indexed_paths if p not in current_paths]
+    if stale_paths:
+     self.rag_engine.delete_documents_by_path(stale_paths)
+
     self._set_rag_status("ready")
    except Exception as e:
     self._set_rag_status(f"error: {e}")

src/rag_engine.py

@@ -149,6 +149,20 @@ class RAGEngine:
   if not os.path.exists(full_path):
    return
    
+  try:
+   mtime = os.path.getmtime(full_path)
+  except Exception:
+   return
+
+  # Incremental check: see if we already have this file with the same mtime
+  try:
+   res = self.collection.get(where={"path": file_path}, limit=1, include=["metadatas"])
+   if res and res["metadatas"] and res["metadatas"][0]:
+    if res["metadatas"][0].get("mtime") == mtime:
+     return
+  except Exception:
+   pass
+
   try:
    with open(full_path, "r", encoding="utf-8", errors="ignore") as f:
     content = f.read()
@@ -167,7 +181,7 @@ class RAGEngine:
    return
 
   ids = [f"{file_path}_{i}" for i in range(len(chunks))]
-  metadatas = [{"path": file_path, "chunk": i} for i in range(len(chunks))]
+  metadatas = [{"path": file_path, "chunk": i, "mtime": mtime} for i in range(len(chunks))]
   self.add_documents(ids, chunks, metadatas)
 
  def _search_mcp(self, query: str, top_k: int = 5) -> List[Dict[str, Any]]:
@@ -216,3 +230,17 @@ class RAGEngine:
   if not self.config.enabled or self.collection == "mock":
    return
   self.collection.delete(ids=ids)
+
+ def get_all_indexed_paths(self) -> List[str]:
+  if not self.config.enabled or self.collection == "mock":
+   return []
+  res = self.collection.get(include=["metadatas"])
+  if not res or not res["metadatas"]:
+   return []
+  return list(set(m.get("path") for m in res["metadatas"] if m.get("path")))
+
+ def delete_documents_by_path(self, file_paths: List[str]):
+  if not self.config.enabled or self.collection == "mock":
+   return
+  for path in file_paths:
+   self.collection.delete(where={"path": path})