par2-rs 0.10.6

PAR2 parity verification and repair
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153

#[path = "support/par2cmdline_turbo_support.rs"]
mod support;

use std::fs;
use std::path::{Path, PathBuf};

use par2_rs::{
    BlockSizing, Par2Creator, Par2CreatorOptions, Par2FileSet, Par2Repairer, Par2RepairerOptions,
    RecoveryAmount, VolumeScheme,
};
use tempfile::tempdir;

fn par2_files(directory: &Path, stem: &str) -> Vec<PathBuf> {
    let mut paths = fs::read_dir(directory)
        .unwrap()
        .map(|entry| entry.unwrap().path())
        .filter(|path| {
            path.extension()
                .is_some_and(|extension| extension.eq_ignore_ascii_case("par2"))
                && path
                    .file_name()
                    .is_some_and(|name| name.to_string_lossy().starts_with(stem))
        })
        .collect::<Vec<_>>();
    paths.sort();
    paths
}

#[test]
#[ignore = "requires a direct PAR2 compatibility executable"]
fn creation_interoperates_in_both_directions() {
    let binaries = support::par2_interop_binaries();
    assert!(
        !binaries.is_empty(),
        "no PAR2 interoperability binary is configured; set PAR2_INTEROP_BINARIES to a platform path list or PAR2_TURBO_BINARY to one executable"
    );

    let directory = tempdir().unwrap();
    fs::write(directory.path().join("empty.bin"), []).unwrap();
    fs::write(directory.path().join("odd.bin"), [1, 2, 3, 4, 5]).unwrap();
    fs::write(
        directory.path().join("payload.bin"),
        (0..4096)
            .map(|index| (index * 17) as u8)
            .collect::<Vec<_>>(),
    )
    .unwrap();

    let mut local_options = Par2CreatorOptions::with_output(
        directory.path().join("local-set"),
        Some(directory.path().to_path_buf()),
        vec![
            directory.path().join("empty.bin"),
            directory.path().join("odd.bin"),
            directory.path().join("payload.bin"),
        ],
    );
    local_options.block_sizing = BlockSizing::Bytes(4);
    local_options.recovery_amount = RecoveryAmount::Count(8);
    local_options.volume_count = Some(3);
    local_options.volume_scheme = VolumeScheme::Variable;
    let local_creator = Par2Creator::new(local_options);
    let local_plan = local_creator.plan().unwrap();
    assert_eq!(local_plan.sources.len(), 2);
    assert!(
        local_plan
            .sources
            .iter()
            .all(|source| source.par2_name != "empty.bin")
    );
    assert_eq!(
        local_plan
            .volumes
            .iter()
            .map(|volume| volume.recovery_count)
            .collect::<Vec<_>>(),
        vec![3, 3, 2]
    );
    let local_outcome = local_creator.create(&local_plan).unwrap();

    for (index, binary) in binaries.iter().enumerate() {
        let binary_label = binary.display();
        let verify_local = support::run_par2_binary(
            binary,
            directory.path(),
            &["verify", local_outcome.main_path.to_str().unwrap()],
        );
        assert!(
            verify_local.status.success(),
            "{binary_label}: external verification of local output failed: {}",
            String::from_utf8_lossy(&verify_local.stderr)
        );

        fs::remove_file(directory.path().join("odd.bin")).unwrap();
        let repair_local = support::run_par2_binary(
            binary,
            directory.path(),
            &["repair", local_outcome.main_path.to_str().unwrap()],
        );
        assert!(
            repair_local.status.success(),
            "{binary_label}: external repair of local output failed: {}",
            String::from_utf8_lossy(&repair_local.stderr)
        );
        assert_eq!(
            fs::read(directory.path().join("odd.bin")).unwrap(),
            [1, 2, 3, 4, 5]
        );

        let external_stem = format!("external-set-{index}");
        let external_output = format!("{external_stem}.par2");
        let external_create_args = vec![
            "create",
            "-r150",
            "-n3",
            external_output.as_str(),
            "empty.bin",
            "odd.bin",
            "payload.bin",
        ];
        let external_create =
            support::run_par2_binary(binary, directory.path(), &external_create_args);
        assert!(
            external_create.status.success(),
            "{binary_label}: external creation failed: {}",
            String::from_utf8_lossy(&external_create.stderr)
        );
        let external_paths = par2_files(directory.path(), &external_stem);
        assert!(external_paths.len() > 1);
        let external_set = Par2FileSet::from_paths(&external_paths).unwrap();
        let mut local_options =
            Par2RepairerOptions::new(directory.path().to_path_buf(), external_paths.clone());
        local_options.file_set = Some(external_set);
        let verified = Par2Repairer::new(local_options).verify_or_repair().unwrap();
        assert_eq!(verified.verification.total_missing_blocks, 0);

        fs::remove_file(directory.path().join("odd.bin")).unwrap();
        let mut repair_options =
            Par2RepairerOptions::new(directory.path().to_path_buf(), external_paths);
        repair_options.repair = true;
        let repaired = Par2Repairer::new(repair_options)
            .verify_or_repair()
            .unwrap();
        assert_eq!(
            fs::read(directory.path().join("odd.bin")).unwrap(),
            [1, 2, 3, 4, 5]
        );
        assert!(matches!(
            repaired.status,
            par2_rs::Par2RepairStatus::Repaired | par2_rs::Par2RepairStatus::Verified
        ));
    }
}