1 | /** |
2 | * Copyright 2021 Alibaba, Inc. and its affiliates. All Rights Reserved. |
3 | * |
4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
5 | * you may not use this file except in compliance with the License. |
6 | * You may obtain a copy of the License at |
7 | * |
8 | * http://www.apache.org/licenses/LICENSE-2.0 |
9 | * |
10 | * Unless required by applicable law or agreed to in writing, software |
11 | * distributed under the License is distributed on an "AS IS" BASIS, |
12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
13 | * See the License for the specific language governing permissions and |
14 | * limitations under the License. |
15 | |
16 | * \author Haichao.chc |
17 | * \date Jun 2021 |
18 | * \brief ForwardReader load forward index and provides read ability. |
19 | */ |
20 | |
21 | #pragma once |
22 | |
23 | #include <memory> |
24 | #include "forward_data.h" |
25 | #include "index_provider.h" |
26 | #include "../snapshot.h" |
27 | #include "../typedef.h" |
28 | |
29 | namespace proxima { |
30 | namespace be { |
31 | namespace index { |
32 | |
33 | class ForwardReader; |
34 | using ForwardReaderPtr = std::shared_ptr<ForwardReader>; |
35 | |
36 | /* |
37 | * ForwardReader load persist forward index, and provides |
38 | * seek ability. |
39 | */ |
40 | class ForwardReader : public IndexProvider { |
41 | public: |
42 | //! Destructor |
43 | virtual ~ForwardReader() = default; |
44 | |
45 | public: |
46 | //! Create an instance and return a shared ptr |
47 | static ForwardReaderPtr Create(const std::string &collection_name, |
48 | const std::string &collection_path, |
49 | SegmentID segment_id); |
50 | |
51 | public: |
52 | //! Open and load forward index file |
53 | virtual int open(const ReadOptions &read_options) = 0; |
54 | |
55 | //! Close and release forward index file |
56 | virtual int close() = 0; |
57 | |
58 | //! Seek a specific doc id |
59 | virtual int seek(idx_t doc_id, ForwardData *forward_data) = 0; |
60 | |
61 | public: |
62 | //! Set min doc id |
63 | void set_start_doc_id(uint32_t val) { |
64 | start_doc_id_ = val; |
65 | } |
66 | |
67 | //! Get min doc id |
68 | uint32_t start_doc_id() { |
69 | return start_doc_id_; |
70 | } |
71 | |
72 | private: |
73 | uint32_t start_doc_id_{0U}; |
74 | }; |
75 | |
76 | } // end namespace index |
77 | } // namespace be |
78 | } // end namespace proxima |
79 | |