初始化提交

backend/app/integrations/vector_store.py

@@ -0,0 +1,84 @@
+"""向量存储接口与工厂。
+
+通过 ``get_vector_store()`` 获取当前配置的后端实现：
+- ``chromadb``（默认）：ChromaDB，内存/HTTP 双模式
+- ``memory``：纯内存实现（测试用）
+
+通过环境变量 ``CHROMADB_HOST`` / ``CHROMADB_PORT`` 控制 ChromaDB 连接模式。
+通过 ``ENABLE_EMBEDDING=false`` 关闭 embedding（纯 SQL 检索）。
+通过 ``VECTOR_DB_TYPE=chroma`` 选择向量库后端。
+"""
+
+from __future__ import annotations
+
+from typing import Any, Protocol, runtime_checkable
+
+
+@runtime_checkable
+class VectorStoreProtocol(Protocol):
+    """向量存储接口。所有后端实现必须遵循此协议。"""
+
+    def add_memory(
+        self,
+        character_id: str,
+        memory_id: str,
+        text: str,
+        embedding: list[float],
+        *,
+        metadata: dict[str, Any] | None = None,
+    ) -> None: ...
+
+    def update_memory(
+        self,
+        character_id: str,
+        memory_id: str,
+        text: str,
+        embedding: list[float],
+        *,
+        metadata: dict[str, Any] | None = None,
+    ) -> None: ...
+
+    def delete_memory(self, character_id: str, memory_id: str) -> None: ...
+
+    def search(
+        self,
+        character_id: str,
+        query: list[float],
+        *,
+        limit: int = 5,
+    ) -> list[dict[str, Any]]: ...
+
+    def count(self, character_id: str) -> int: ...
+
+
+_vector_store: VectorStoreProtocol | None = None
+
+
+def get_vector_store() -> VectorStoreProtocol | None:
+    """根据配置返回向量存储后端；embedding 关闭时返回 None。"""
+    from app.core.config import settings
+
+    if not settings.vector_db_enabled:
+        return None
+
+    global _vector_store  # noqa: PLW0603
+    if _vector_store is not None:
+        return _vector_store
+
+    backend = settings.vector_db_type
+    if backend == "memory":
+        from app.integrations.chromadb.memory_store import MemoryVectorStore
+
+        _vector_store = MemoryVectorStore()
+    else:
+        # 默认 chromadb
+        from app.integrations.chromadb.client import ChromaDBVectorStore
+
+        _vector_store = ChromaDBVectorStore()
+    return _vector_store
+
+
+def reset_vector_store() -> None:
+    """重置单例（测试用）。"""
+    global _vector_store  # noqa: PLW0603
+    _vector_store = None