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
|
use super::RenderError;
use crate::{
blobservice::BlobService,
directoryservice::DirectoryService,
proto::{self, NamedNode},
};
use count_write::CountWrite;
use nix_compat::nar;
use sha2::{Digest, Sha256};
use std::{io, sync::Arc};
use tokio::{io::BufReader, task::spawn_blocking};
use tracing::warn;
/// Invoke [write_nar], and return the size and sha256 digest of the produced
/// NAR output.
pub async fn calculate_size_and_sha256(
root_node: &proto::node::Node,
blob_service: Arc<dyn BlobService>,
directory_service: Arc<dyn DirectoryService>,
) -> Result<(u64, [u8; 32]), RenderError> {
let h = Sha256::new();
let cw = CountWrite::from(h);
let cw = write_nar(cw, root_node, blob_service, directory_service).await?;
Ok((cw.count(), cw.into_inner().finalize().into()))
}
/// Accepts a [proto::node::Node] pointing to the root of a (store) path,
/// and uses the passed blob_service and directory_service to
/// perform the necessary lookups as it traverses the structure.
/// The contents in NAR serialization are writen to the passed [std::io::Write].
///
/// The writer is passed back in the return value. This is done because async Rust
/// lacks scoped blocking tasks, so we need to transfer ownership of the writer
/// internally.
///
/// # Panics
/// This will panic if called outside the context of a Tokio runtime.
pub async fn write_nar<W: std::io::Write + Send + 'static>(
mut w: W,
proto_root_node: &proto::node::Node,
blob_service: Arc<dyn BlobService>,
directory_service: Arc<dyn DirectoryService>,
) -> Result<W, RenderError> {
let tokio_handle = tokio::runtime::Handle::current();
let proto_root_node = proto_root_node.clone();
spawn_blocking(move || {
// Initialize NAR writer
let nar_root_node = nar::writer::open(&mut w).map_err(RenderError::NARWriterError)?;
walk_node(
tokio_handle,
nar_root_node,
&proto_root_node,
blob_service,
directory_service,
)?;
Ok(w)
})
.await
.unwrap()
}
/// Process an intermediate node in the structure.
/// This consumes the node.
fn walk_node(
tokio_handle: tokio::runtime::Handle,
nar_node: nar::writer::Node,
proto_node: &proto::node::Node,
blob_service: Arc<dyn BlobService>,
directory_service: Arc<dyn DirectoryService>,
) -> Result<(), RenderError> {
match proto_node {
proto::node::Node::Symlink(proto_symlink_node) => {
nar_node
.symlink(&proto_symlink_node.target)
.map_err(RenderError::NARWriterError)?;
}
proto::node::Node::File(proto_file_node) => {
let digest = proto_file_node.digest.clone().try_into().map_err(|_e| {
warn!(
file_node = ?proto_file_node,
"invalid digest length in file node",
);
RenderError::StoreError(crate::Error::StorageError(
"invalid digest len in file node".to_string(),
))
})?;
let blob_reader = match tokio_handle
.block_on(async { blob_service.open_read(&digest).await })
.map_err(RenderError::StoreError)?
{
Some(blob_reader) => Ok(BufReader::new(blob_reader)),
None => Err(RenderError::NARWriterError(io::Error::new(
io::ErrorKind::NotFound,
format!("blob with digest {} not found", &digest),
))),
}?;
nar_node
.file(
proto_file_node.executable,
proto_file_node.size.into(),
&mut tokio_util::io::SyncIoBridge::new(blob_reader),
)
.map_err(RenderError::NARWriterError)?;
}
proto::node::Node::Directory(proto_directory_node) => {
let digest = proto_directory_node
.digest
.clone()
.try_into()
.map_err(|_e| {
RenderError::StoreError(crate::Error::StorageError(
"invalid digest len in directory node".to_string(),
))
})?;
// look it up with the directory service
match tokio_handle
.block_on(async { directory_service.get(&digest).await })
.map_err(RenderError::StoreError)?
{
// if it's None, that's an error!
None => {
return Err(RenderError::DirectoryNotFound(
digest,
proto_directory_node.name.clone(),
))
}
Some(proto_directory) => {
// start a directory node
let mut nar_node_directory =
nar_node.directory().map_err(RenderError::NARWriterError)?;
// for each node in the directory, create a new entry with its name,
// and then invoke walk_node on that entry.
for proto_node in proto_directory.nodes() {
let child_node = nar_node_directory
.entry(proto_node.get_name())
.map_err(RenderError::NARWriterError)?;
walk_node(
tokio_handle.clone(),
child_node,
&proto_node,
blob_service.clone(),
directory_service.clone(),
)?;
}
// close the directory
nar_node_directory
.close()
.map_err(RenderError::NARWriterError)?;
}
}
}
}
Ok(())
}
|
