opendal_testkit/
read.rs

1// Licensed to the Apache Software Foundation (ASF) under one
2// or more contributor license agreements.  See the NOTICE file
3// distributed with this work for additional information
4// regarding copyright ownership.  The ASF licenses this file
5// to you under the Apache License, Version 2.0 (the
6// "License"); you may not use this file except in compliance
7// with the License.  You may obtain a copy of the License at
8//
9//   http://www.apache.org/licenses/LICENSE-2.0
10//
11// Unless required by applicable law or agreed to in writing,
12// software distributed under the License is distributed on an
13// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
14// KIND, either express or implied.  See the License for the
15// specific language governing permissions and limitations
16// under the License.
17
18use bytes::Bytes;
19use opendal_core::*;
20use rand::Rng;
21use rand::rng;
22
23use crate::utils::sha256_digest;
24
25/// A reader operation executed by [`ReadChecker`].
26#[derive(Debug, Clone, Copy, Eq, PartialEq)]
27pub enum ReadAction {
28    /// Read `size` bytes beginning at `offset`.
29    ///
30    /// The first field is the offset and the second field is the requested
31    /// size. A reader can return fewer bytes at the end of an object.
32    Read(usize, usize),
33}
34
35/// Generates reference data and verifies reads against it.
36pub struct ReadChecker {
37    /// Data that callers write to the storage before checking reads.
38    raw_data: Bytes,
39}
40
41impl ReadChecker {
42    /// Create a checker containing `size` bytes of random reference data.
43    ///
44    /// Random input makes the checker sensitive to misplaced or repeated data;
45    /// callers should not depend on the generated content.
46    pub fn new(size: usize) -> Self {
47        let mut rng = rng();
48        let mut data = vec![0; size];
49        rng.fill_bytes(&mut data);
50
51        let raw_data = Bytes::from(data);
52
53        Self { raw_data }
54    }
55
56    /// Return the reference data that should be written before a check.
57    pub fn data(&self) -> Bytes {
58        self.raw_data.clone()
59    }
60
61    /// check_read checks the correctness of the read process after a read action.
62    ///
63    /// - buf_size is the read action's buf size.
64    /// - output is the output of this read action.
65    fn check_read(&self, offset: usize, size: usize, output: &[u8]) {
66        if size == 0 {
67            assert_eq!(
68                output.len(),
69                0,
70                "check read failed: output must be empty if buf_size is 0"
71            );
72            return;
73        }
74
75        if size > 0 && output.is_empty() {
76            assert!(
77                offset >= self.raw_data.len(),
78                "check read failed: no data read means cur must outsides of ranged_data",
79            );
80            return;
81        }
82
83        assert!(
84            offset + output.len() <= self.raw_data.len(),
85            "check read failed: cur + output length must be less than ranged_data length, offset: {}, output: {}, ranged_data: {}",
86            offset,
87            output.len(),
88            self.raw_data.len(),
89        );
90
91        let expected = &self.raw_data[offset..offset + output.len()];
92
93        if output != expected {
94            assert_eq!(
95                sha256_digest(output),
96                sha256_digest(expected),
97                "check read failed: output bs is different with expected bs",
98            );
99        }
100    }
101
102    /// Execute `actions` and verify each result against the reference data.
103    ///
104    /// This method panics if a read fails or returns incorrect data.
105    pub async fn check(&mut self, r: Reader, actions: &[ReadAction]) {
106        for action in actions {
107            match *action {
108                ReadAction::Read(offset, size) => {
109                    let bs = r
110                        .read(offset as u64..(offset + size) as u64)
111                        .await
112                        .expect("read must success");
113                    self.check_read(offset, size, bs.to_bytes().as_ref());
114                }
115            }
116        }
117    }
118}
opendal_testkit/read.rs

opendal_testkit/
read.rs
