Update knowledge base layout

api/app/routers/knowledge.py

@@ -87,10 +87,21 @@ def get_knowledge_base(kb_id: str, db: Session = Depends(get_db)):
 
 @router.post("/bases")
 def create_knowledge_base(data: KnowledgeBaseCreate, user_id: int = 1, db: Session = Depends(get_db)):
+    name = (data.name or "").strip()
+    if not name:
+        raise HTTPException(status_code=400, detail="Knowledge base name cannot be empty")
+
+    exists = db.query(KnowledgeBase).filter(
+        KnowledgeBase.user_id == user_id,
+        KnowledgeBase.name == name
+    ).first()
+    if exists:
+        raise HTTPException(status_code=400, detail=f"Knowledge base name already exists: {name}")
+
     kb = KnowledgeBase(
         id=str(uuid.uuid4())[:8],
         user_id=user_id,
-        name=data.name,
+        name=name,
         description=data.description,
         embedding_model=data.embeddingModel,
         chunk_size=data.chunkSize,
@@ -101,8 +112,11 @@ def create_knowledge_base(data: KnowledgeBaseCreate, user_id: int = 1, db: Sessi
     db.refresh(kb)
     try:
         vector_store.create_collection(kb.id, data.embeddingModel)
-    except Exception:
-        pass
+    except Exception as exc:
+        # Keep DB and vector store consistent on create failure
+        db.delete(kb)
+        db.commit()
+        raise HTTPException(status_code=502, detail=f"Failed to create ChromaDB collection: {exc}") from exc
     return kb_to_dict(kb)
 
 
@@ -117,8 +131,38 @@ def update_knowledge_base(kb_id: str, data: KnowledgeBaseUpdate, db: Session = D
         "chunkSize": "chunk_size",
         "chunkOverlap": "chunk_overlap",
     }
+    if "name" in update_data:
+        update_data["name"] = (update_data["name"] or "").strip()
+        if not update_data["name"]:
+            raise HTTPException(status_code=400, detail="Knowledge base name cannot be empty")
+        name_exists = db.query(KnowledgeBase).filter(
+            KnowledgeBase.user_id == kb.user_id,
+            KnowledgeBase.name == update_data["name"],
+            KnowledgeBase.id != kb.id
+        ).first()
+        if name_exists:
+            raise HTTPException(status_code=400, detail=f"Knowledge base name already exists: {update_data['name']}")
+
+    embedding_changed = "embeddingModel" in update_data and update_data["embeddingModel"] != kb.embedding_model
+    if embedding_changed and kb.chunk_count > 0:
+        raise HTTPException(
+            status_code=400,
+            detail="Cannot change embedding model when knowledge base has indexed chunks. Remove documents first."
+        )
+
     for field, value in update_data.items():
         setattr(kb, field_map.get(field, field), value)
+
+    if embedding_changed:
+        try:
+            vector_store.delete_collection(kb_id)
+        except Exception:
+            pass
+        try:
+            vector_store.create_collection(kb_id, kb.embedding_model)
+        except Exception as exc:
+            raise HTTPException(status_code=502, detail=f"Failed to update ChromaDB collection: {exc}") from exc
+
     kb.updated_at = datetime.utcnow()
     db.commit()
     db.refresh(kb)
@@ -130,15 +174,18 @@ def delete_knowledge_base(kb_id: str, db: Session = Depends(get_db)):
     kb = db.query(KnowledgeBase).filter(KnowledgeBase.id == kb_id).first()
     if not kb:
         raise HTTPException(status_code=404, detail="Knowledge base not found")
+    vector_deleted = True
     try:
         vector_store.delete_collection(kb_id)
     except Exception:
-        pass
+        vector_deleted = False
     docs = db.query(KnowledgeDocument).filter(KnowledgeDocument.kb_id == kb_id).all()
     for doc in docs:
         db.delete(doc)
     db.delete(kb)
     db.commit()
+    if not vector_deleted:
+        return {"message": "Deleted successfully", "warning": "Knowledge base deleted but failed to remove ChromaDB collection"}
     return {"message": "Deleted successfully"}