about summary refs log tree commit diff
path: root/tvix/castore/src/import/mod.rs
blob: a9ac0be6b0642b27f2c654b7856f3ff19eb85279 (plain) (blame)
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
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
//! The main library function here is [ingest_entries], receiving a stream of
//! [IngestionEntry].
//!
//! Specific implementations, such as ingesting from the filesystem, live in
//! child modules.

use crate::directoryservice::DirectoryPutter;
use crate::directoryservice::DirectoryService;
use crate::path::{Path, PathBuf};
use crate::proto::node::Node;
use crate::proto::Directory;
use crate::proto::DirectoryNode;
use crate::proto::FileNode;
use crate::proto::SymlinkNode;
use crate::B3Digest;
use futures::{Stream, StreamExt};
use tracing::Level;

use std::collections::HashMap;
use tracing::instrument;

mod error;
pub use error::IngestionError;

pub mod archive;
pub mod blobs;
pub mod fs;

/// Ingests [IngestionEntry] from the given stream into a the passed [DirectoryService].
/// On success, returns the root [Node].
///
/// The stream must have the following invariants:
/// - All children entries must come before their parents.
/// - The last entry must be the root node which must have a single path component.
/// - Every entry should have a unique path, and only consist of normal components.
///   This means, no windows path prefixes, absolute paths, `.` or `..`.
/// - All referenced directories must have an associated directory entry in the stream.
///   This means if there is a file entry for `foo/bar`, there must also be a `foo` directory
///   entry.
///
/// Internally we maintain a [HashMap] of [PathBuf] to partially populated [Directory] at that
/// path. Once we receive an [IngestionEntry] for the directory itself, we remove it from the
/// map and upload it to the [DirectoryService] through a lazily created [DirectoryPutter].
///
/// On success, returns the root node.
#[instrument(skip_all, ret(level = Level::TRACE), err)]
pub async fn ingest_entries<DS, S, E>(
    directory_service: DS,
    mut entries: S,
) -> Result<Node, IngestionError<E>>
where
    DS: DirectoryService,
    S: Stream<Item = Result<IngestionEntry, E>> + Send + std::marker::Unpin,
    E: std::error::Error,
{
    // For a given path, this holds the [Directory] structs as they are populated.
    let mut directories: HashMap<PathBuf, Directory> = HashMap::default();
    let mut maybe_directory_putter: Option<Box<dyn DirectoryPutter>> = None;

    let root_node = loop {
        let mut entry = entries
            .next()
            .await
            // The last entry of the stream must have 1 path component, after which
            // we break the loop manually.
            .expect("Tvix bug: unexpected end of stream")?;

        let name = entry
            .path()
            .file_name()
            // If this is the root node, it will have an empty name.
            .unwrap_or_default()
            .to_owned()
            .into();

        let node = match &mut entry {
            IngestionEntry::Dir { .. } => {
                // If the entry is a directory, we traversed all its children (and
                // populated it in `directories`).
                // If we don't have it in directories, it's a directory without
                // children.
                let directory = directories
                    .remove(entry.path())
                    // In that case, it contained no children
                    .unwrap_or_default();

                let directory_size = directory.size();
                let directory_digest = directory.digest();

                // Use the directory_putter to upload the directory.
                // If we don't have one yet (as that's the first one to upload),
                // initialize the putter.
                maybe_directory_putter
                    .get_or_insert_with(|| directory_service.put_multiple_start())
                    .put(directory)
                    .await
                    .map_err(|e| {
                        IngestionError::UploadDirectoryError(entry.path().to_owned(), e)
                    })?;

                Node::Directory(DirectoryNode {
                    name,
                    digest: directory_digest.into(),
                    size: directory_size,
                })
            }
            IngestionEntry::Symlink { ref target, .. } => Node::Symlink(SymlinkNode {
                name,
                target: target.to_owned().into(),
            }),
            IngestionEntry::Regular {
                size,
                executable,
                digest,
                ..
            } => Node::File(FileNode {
                name,
                digest: digest.to_owned().into(),
                size: *size,
                executable: *executable,
            }),
        };

        let parent = entry
            .path()
            .parent()
            .expect("Tvix bug: got entry with root node");

        if parent == crate::Path::ROOT {
            break node;
        } else {
            // record node in parent directory, creating a new [Directory] if not there yet.
            directories.entry(parent.to_owned()).or_default().add(node);
        }
    };

    assert!(
        entries.count().await == 0,
        "Tvix bug: left over elements in the stream"
    );

    assert!(
        directories.is_empty(),
        "Tvix bug: left over directories after processing ingestion stream"
    );

    // if there were directories uploaded, make sure we flush the putter, so
    // they're all persisted to the backend.
    if let Some(mut directory_putter) = maybe_directory_putter {
        #[cfg_attr(not(debug_assertions), allow(unused))]
        let root_directory_digest = directory_putter
            .close()
            .await
            .map_err(|e| IngestionError::FinalizeDirectoryUpload(e))?;

        #[cfg(debug_assertions)]
        {
            if let Node::Directory(directory_node) = &root_node {
                debug_assert_eq!(
                    root_directory_digest,
                    directory_node
                        .digest
                        .to_vec()
                        .try_into()
                        .expect("invalid digest len")
                )
            } else {
                unreachable!("Tvix bug: directory putter initialized but no root directory node");
            }
        }
    };

    Ok(root_node)
}

#[derive(Debug, Clone, Eq, PartialEq)]
pub enum IngestionEntry {
    Regular {
        path: PathBuf,
        size: u64,
        executable: bool,
        digest: B3Digest,
    },
    Symlink {
        path: PathBuf,
        target: Vec<u8>,
    },
    Dir {
        path: PathBuf,
    },
}

impl IngestionEntry {
    fn path(&self) -> &Path {
        match self {
            IngestionEntry::Regular { path, .. } => path,
            IngestionEntry::Symlink { path, .. } => path,
            IngestionEntry::Dir { path } => path,
        }
    }

    fn is_dir(&self) -> bool {
        matches!(self, IngestionEntry::Dir { .. })
    }
}

#[cfg(test)]
mod test {
    use rstest::rstest;

    use crate::fixtures::{DIRECTORY_COMPLICATED, DIRECTORY_WITH_KEEP, EMPTY_BLOB_DIGEST};
    use crate::proto::node::Node;
    use crate::proto::{Directory, DirectoryNode, FileNode, SymlinkNode};
    use crate::{directoryservice::MemoryDirectoryService, fixtures::DUMMY_DIGEST};

    use super::ingest_entries;
    use super::IngestionEntry;

    #[rstest]
    #[case::single_file(vec![IngestionEntry::Regular {
        path: "foo".parse().unwrap(),
        size: 42,
        executable: true,
        digest: DUMMY_DIGEST.clone(),
    }],
        Node::File(FileNode { name: "foo".into(), digest: DUMMY_DIGEST.clone().into(), size: 42, executable: true }
    ))]
    #[case::single_symlink(vec![IngestionEntry::Symlink {
        path: "foo".parse().unwrap(),
        target: b"blub".into(),
    }],
        Node::Symlink(SymlinkNode { name: "foo".into(), target: "blub".into()})
    )]
    #[case::single_dir(vec![IngestionEntry::Dir {
        path: "foo".parse().unwrap(),
    }],
        Node::Directory(DirectoryNode { name: "foo".into(), digest: Directory::default().digest().into(), size: Directory::default().size()})
    )]
    #[case::dir_with_keep(vec![
        IngestionEntry::Regular {
            path: "foo/.keep".parse().unwrap(),
            size: 0,
            executable: false,
            digest: EMPTY_BLOB_DIGEST.clone(),
        },
        IngestionEntry::Dir {
            path: "foo".parse().unwrap(),
        },
    ],
        Node::Directory(DirectoryNode { name: "foo".into(), digest: DIRECTORY_WITH_KEEP.digest().into(), size: DIRECTORY_WITH_KEEP.size() })
    )]
    /// This is intentionally a bit unsorted, though it still satisfies all
    /// requirements we have on the order of elements in the stream.
    #[case::directory_complicated(vec![
        IngestionEntry::Regular {
            path: "blub/.keep".parse().unwrap(),
            size: 0,
            executable: false,
            digest: EMPTY_BLOB_DIGEST.clone(),
        },
        IngestionEntry::Regular {
            path: "blub/keep/.keep".parse().unwrap(),
            size: 0,
            executable: false,
            digest: EMPTY_BLOB_DIGEST.clone(),
        },
        IngestionEntry::Dir {
            path: "blub/keep".parse().unwrap(),
        },
        IngestionEntry::Symlink {
            path: "blub/aa".parse().unwrap(),
            target: b"/nix/store/somewhereelse".into(),
        },
        IngestionEntry::Dir {
            path: "blub".parse().unwrap(),
        },
    ],
        Node::Directory(DirectoryNode { name: "blub".into(), digest: DIRECTORY_COMPLICATED.digest().into(), size:DIRECTORY_COMPLICATED.size() })
    )]
    #[tokio::test]
    async fn test_ingestion(#[case] entries: Vec<IngestionEntry>, #[case] exp_root_node: Node) {
        let directory_service = MemoryDirectoryService::default();

        let root_node = ingest_entries(
            directory_service.clone(),
            futures::stream::iter(entries.into_iter().map(Ok::<_, std::io::Error>)),
        )
        .await
        .expect("must succeed");

        assert_eq!(exp_root_node, root_node, "root node should match");
    }

    #[rstest]
    #[should_panic]
    #[case::empty_entries(vec![])]
    #[should_panic]
    #[case::missing_intermediate_dir(vec![
        IngestionEntry::Regular {
            path: "blub/.keep".parse().unwrap(),
            size: 0,
            executable: false,
            digest: EMPTY_BLOB_DIGEST.clone(),
        },
    ])]
    #[should_panic]
    #[case::leaf_after_parent(vec![
        IngestionEntry::Dir {
            path: "blub".parse().unwrap(),
        },
        IngestionEntry::Regular {
            path: "blub/.keep".parse().unwrap(),
            size: 0,
            executable: false,
            digest: EMPTY_BLOB_DIGEST.clone(),
        },
    ])]
    #[should_panic]
    #[case::root_in_entry(vec![
        IngestionEntry::Regular {
            path: ".keep".parse().unwrap(),
            size: 0,
            executable: false,
            digest: EMPTY_BLOB_DIGEST.clone(),
        },
        IngestionEntry::Dir {
            path: "".parse().unwrap(),
        },
    ])]
    #[tokio::test]
    async fn test_ingestion_fail(#[case] entries: Vec<IngestionEntry>) {
        let directory_service = MemoryDirectoryService::default();

        let _ = ingest_entries(
            directory_service.clone(),
            futures::stream::iter(entries.into_iter().map(Ok::<_, std::io::Error>)),
        )
        .await;
    }
}