合并两个firestore querystream

Question

我正在尝试创建一个Instagram feed，为此，我有两个查询，一个查询所有公开帖子，另一篇是我关注的用户的私人帖子。

我很难将两个流融合在一起，并且在结尾处仍具有流;我试图使用RXDART，但我觉得自己是不可能的。

  Stream<QuerySnapshot<Map<String, dynamic>>> getUserPostsByUuid(
      {String? userUuid, List<dynamic>? followers}) {

     List<String> acceptedFollowersUuid = [];

      if (followers != null) {
        for (var follower in followers) {
          acceptedFollowersUuid.add(follower['uuid']);
        }
      }

      final _firestoreSubscribe = _firestore
          .collection('posts')
          .where('userId',
              whereIn:
                  acceptedFollowersUuid.isEmpty ? [''] : acceptedFollowersUuid)
          .orderBy('timestamp', descending: true)
          .snapshots();

      final _firestorePublic = _firestore
          .collection('posts')
          .where('isPublic', isEqualTo: true)
          .orderBy('timestamp', descending: true)
          .snapshots();


      // Should return a Stream<QuerySnapshot<Map<String, dynamic>>> with data from both _firestorePublic & _firestoreSubscribe without duplicate.
      return _firestorePublic;

  }