feat: multi-collection support — each project uses its own isolated collection

src/server/app.py

@@ -21,14 +21,20 @@ logger = logging.getLogger("md-vector-db")
 class IngestRequest(BaseModel):
     file_path: str | None = None
     content: str | None = None
-    file_name: str | None = Field(
-        default=None, max_length=255
+    file_name: str | None = Field(default=None, max_length=255)
+    collection: str | None = Field(
+        default=None, max_length=128,
+        description="目标 collection（默认使用配置文件中的 collection_name）",
     )
 
 
 class SearchRequest(BaseModel):
     query: str = Field(..., min_length=1, max_length=2000)
     top_k: int = Field(default=10, ge=1, le=100)
+    collection: str | None = Field(
+        default=None, max_length=128,
+        description="检索的 collection（默认使用配置文件中的 collection_name）",
+    )
 
 
 # -- 路径安全检查 --
@@ -64,9 +70,7 @@ def health(state: AppState = Depends(get_state)):
 
 @app.get("/api/v1/collections")
 def list_collections(state: AppState = Depends(get_state)):
-    info = state.searcher.get_collection_info()
-    sources = state.searcher.list_sources()
-    return {"collections": [info], "sources": sources}
+    return {"collections": state.list_collections_with_stats()}
 
 
 @app.post("/api/v1/ingest")
@@ -75,6 +79,7 @@ def ingest_document(
     state: AppState = Depends(get_state),
     _: bool = Depends(verify_api_key),
 ):
+    ingestor = state.get_ingestor(req.collection)
     try:
         if req.file_path:
             if not _is_safe_path(req.file_path):
@@ -85,14 +90,14 @@ def ingest_document(
                 raise HTTPException(status_code=400, detail="不允许访问当前目录外的路径")
             if not path.exists():
                 raise HTTPException(status_code=404, detail=f"文件不存在: {path.name}")
-            count = state.ingestor.ingest_file(str(path))
+            count = ingestor.ingest_file(str(path))
             file_name = path.name
         elif req.content:
             file_name = req.file_name or "untitled.md"
-            count = state.ingestor.ingest_content(req.content, file_name)
+            count = ingestor.ingest_content(req.content, file_name)
         else:
             raise HTTPException(status_code=400, detail="需要提供 file_path 或 content")
-        return {"status": "ok", "chunks": count, "file": file_name}
+        return {"status": "ok", "chunks": count, "file": file_name, "collection": ingestor.collection_name}
     except HTTPException:
         raise
     except Exception:
@@ -106,8 +111,9 @@ def search_documents(
     state: AppState = Depends(get_state),
     _: bool = Depends(verify_api_key),
 ):
-    results = state.searcher.search(req.query, top_k=req.top_k)
-    return {"results": results}
+    searcher = state.get_searcher(req.collection)
+    results = searcher.search(req.query, top_k=req.top_k)
+    return {"results": results, "collection": searcher.collection_name}
 
 
 @app.delete("/api/v1/documents/{file_name}")
@@ -115,8 +121,10 @@ def delete_document(
     file_name: str,
     state: AppState = Depends(get_state),
     _: bool = Depends(verify_api_key),
+    collection: str | None = None,
 ):
-    deleted = state.searcher.delete_by_source(file_name)
+    searcher = state.get_searcher(collection)
+    deleted = searcher.delete_by_source(file_name)
     if not deleted:
         raise HTTPException(status_code=404, detail=f"文档不存在: {file_name}")
-    return {"status": "ok", "file": file_name}
+    return {"status": "ok", "file": file_name, "collection": searcher.collection_name}

src/server/deps.py

@@ -12,7 +12,7 @@ logger = logging.getLogger(__name__)
 
 
 class AppState:
-    """应用级共享状态."""
+    """应用级共享状态 — db 和 embedder 全局共享, searcher/ingestor 按 collection 懒创建."""
 
     def __init__(self):
         config_path = os.environ.get("MD_VECTOR_CONFIG", "config.yaml")
@@ -22,20 +22,48 @@ class AppState:
             "MD_VECTOR_DB_DATA_DIR", self.config.chroma.persist_dir
         )
         self.db = VectorDB(persist_dir=data_dir)
-
         self.embedder = create_embedder(self.config.embed)
 
-        collection = os.environ.get(
+        self.default_collection = os.environ.get(
             "MD_VECTOR_DB_COLLECTION", self.config.chroma.collection_name
         )
-        self.searcher = Searcher(self.db, self.embedder, collection)
-        self.ingestor = DocumentIngestor(self.db, self.embedder, collection)
+
+        # 按 collection 懒加载 searcher / ingestor
+        self._searchers: dict[str, Searcher] = {}
+        self._ingestors: dict[str, DocumentIngestor] = {}
+
+    def get_searcher(self, collection: str | None = None) -> Searcher:
+        name = collection or self.default_collection
+        if name not in self._searchers:
+            self._searchers[name] = Searcher(self.db, self.embedder, name)
+        return self._searchers[name]
+
+    def get_ingestor(self, collection: str | None = None) -> DocumentIngestor:
+        name = collection or self.default_collection
+        if name not in self._ingestors:
+            self._ingestors[name] = DocumentIngestor(self.db, self.embedder, name)
+        return self._ingestors[name]
+
+    def list_collections_with_stats(self) -> list[dict]:
+        """列出所有 collection 及其统计."""
+        result = []
+        all_names = set(self._searchers.keys()) | set(self._ingestors.keys())
+        all_names.add(self.default_collection)
+        for name in sorted(all_names):
+            try:
+                coll = self.db.get_or_create_collection(name)
+                result.append({"name": name, "count": coll.count()})
+            except Exception:
+                result.append({"name": name, "count": 0})
+        return result
 
     def is_healthy(self) -> dict:
         """真实健康检查: 验证 ChromaDB 和 Embedder 是否可用."""
         status = {"status": "ok", "checks": {}}
         try:
-            count = self.searcher.collection.count()
+            count = self.db.get_or_create_collection(
+                self.default_collection
+            ).count()
             status["checks"]["chromadb"] = {"status": "ok", "count": count}
         except Exception as e:
             status["checks"]["chromadb"] = {"status": "error", "detail": str(e)}
@@ -59,3 +87,8 @@ def get_state() -> AppState:
         logger.info("初始化应用状态...")
         _state = AppState()
     return _state
+
+
+def get_default_collection() -> str:
+    """获取默认 collection 名, 供 CLI 等非 HTTP 场景使用."""
+    return get_state().default_collection