fix(repository): Move backend code into subdirectory

Signed-off-by: Tilman Vatteroth <git@tilmanvatteroth.de>

backend/src/utils/session.ts

@@ -0,0 +1,37 @@
+/*
+ * SPDX-FileCopyrightText: 2021 The HedgeDoc developers (see AUTHORS file)
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+import { INestApplication } from '@nestjs/common';
+import { TypeormStore } from 'connect-typeorm';
+import session from 'express-session';
+
+import { AuthConfig } from '../config/auth.config';
+
+export const HEDGEDOC_SESSION = 'hedgedoc-session';
+
+/**
+ * Set up the session middleware via the given authConfig.
+ * @param {INestApplication} app - the nest application to configure the middleware for.
+ * @param {AuthConfig} authConfig - the authConfig to configure the middleware with.
+ * @param {TypeormStore} typeormStore - the typeormStore to handle session data.
+ */
+export function setupSessionMiddleware(
+  app: INestApplication,
+  authConfig: AuthConfig,
+  typeormStore: TypeormStore,
+): void {
+  app.use(
+    session({
+      name: HEDGEDOC_SESSION,
+      secret: authConfig.session.secret,
+      cookie: {
+        maxAge: authConfig.session.lifetime,
+      },
+      resave: false,
+      saveUninitialized: false,
+      store: typeormStore,
+    }),
+  );
+}