feat：新增dify1.11.1版本

dify_1.11.1/api/services/attachment_service.py

@@ -0,0 +1,31 @@
+import base64
+
+from sqlalchemy import Engine
+from sqlalchemy.orm import sessionmaker
+from werkzeug.exceptions import NotFound
+
+from extensions.ext_storage import storage
+from models.model import UploadFile
+
+PREVIEW_WORDS_LIMIT = 3000
+
+
+class AttachmentService:
+    _session_maker: sessionmaker
+
+    def __init__(self, session_factory: sessionmaker | Engine | None = None):
+        if isinstance(session_factory, Engine):
+            self._session_maker = sessionmaker(bind=session_factory)
+        elif isinstance(session_factory, sessionmaker):
+            self._session_maker = session_factory
+        else:
+            raise AssertionError("must be a sessionmaker or an Engine.")
+
+    def get_file_base64(self, file_id: str) -> str:
+        upload_file = (
+            self._session_maker(expire_on_commit=False).query(UploadFile).where(UploadFile.id == file_id).first()
+        )
+        if not upload_file:
+            raise NotFound("File not found")
+        blob = storage.load_once(upload_file.key)
+        return base64.b64encode(blob).decode()