forked from denoland/deno
-
Notifications
You must be signed in to change notification settings - Fork 0
/
emit.rs
209 lines (183 loc) · 6.01 KB
/
emit.rs
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
// Copyright 2018-2023 the Deno authors. All rights reserved. MIT license.
use std::path::PathBuf;
use deno_ast::ModuleSpecifier;
use deno_core::anyhow::anyhow;
use deno_core::error::AnyError;
use deno_core::serde_json;
use serde::Deserialize;
use serde::Serialize;
use super::DiskCache;
use super::FastInsecureHasher;
#[derive(Debug, Deserialize, Serialize)]
struct EmitMetadata {
pub source_hash: String,
pub emit_hash: String,
}
/// The cache that stores previously emitted files.
#[derive(Clone)]
pub struct EmitCache {
disk_cache: DiskCache,
cli_version: String,
}
impl EmitCache {
pub fn new(disk_cache: DiskCache) -> Self {
Self {
disk_cache,
cli_version: crate::version::deno(),
}
}
/// Gets the emitted code with embedded sourcemap from the cache.
///
/// The expected source hash is used in order to verify
/// that you're getting a value from the cache that is
/// for the provided source.
///
/// Cached emits from previous CLI releases will not be returned
/// or emits that do not match the source.
pub fn get_emit_code(
&self,
specifier: &ModuleSpecifier,
expected_source_hash: u64,
) -> Option<String> {
let meta_filename = self.get_meta_filename(specifier)?;
let emit_filename = self.get_emit_filename(specifier)?;
// load and verify the meta data file is for this source and CLI version
let bytes = self.disk_cache.get(&meta_filename).ok()?;
let meta: EmitMetadata = serde_json::from_slice(&bytes).ok()?;
if meta.source_hash != expected_source_hash.to_string() {
return None;
}
// load and verify the emit is for the meta data
let emit_bytes = self.disk_cache.get(&emit_filename).ok()?;
if meta.emit_hash != compute_emit_hash(&emit_bytes, &self.cli_version) {
return None;
}
// everything looks good, return it
let emit_text = String::from_utf8(emit_bytes).ok()?;
Some(emit_text)
}
/// Gets the filepath which stores the emit.
pub fn get_emit_filepath(
&self,
specifier: &ModuleSpecifier,
) -> Option<PathBuf> {
Some(
self
.disk_cache
.location
.join(self.get_emit_filename(specifier)?),
)
}
/// Sets the emit code in the cache.
pub fn set_emit_code(
&self,
specifier: &ModuleSpecifier,
source_hash: u64,
code: &str,
) {
if let Err(err) = self.set_emit_code_result(specifier, source_hash, code) {
// should never error here, but if it ever does don't fail
if cfg!(debug_assertions) {
panic!("Error saving emit data ({specifier}): {err}");
} else {
log::debug!("Error saving emit data({}): {}", specifier, err);
}
}
}
fn set_emit_code_result(
&self,
specifier: &ModuleSpecifier,
source_hash: u64,
code: &str,
) -> Result<(), AnyError> {
let meta_filename = self
.get_meta_filename(specifier)
.ok_or_else(|| anyhow!("Could not get meta filename."))?;
let emit_filename = self
.get_emit_filename(specifier)
.ok_or_else(|| anyhow!("Could not get emit filename."))?;
// save the metadata
let metadata = EmitMetadata {
source_hash: source_hash.to_string(),
emit_hash: compute_emit_hash(code.as_bytes(), &self.cli_version),
};
self
.disk_cache
.set(&meta_filename, &serde_json::to_vec(&metadata)?)?;
// save the emit source
self.disk_cache.set(&emit_filename, code.as_bytes())?;
Ok(())
}
fn get_meta_filename(&self, specifier: &ModuleSpecifier) -> Option<PathBuf> {
self
.disk_cache
.get_cache_filename_with_extension(specifier, "meta")
}
fn get_emit_filename(&self, specifier: &ModuleSpecifier) -> Option<PathBuf> {
self
.disk_cache
.get_cache_filename_with_extension(specifier, "js")
}
}
fn compute_emit_hash(bytes: &[u8], cli_version: &str) -> String {
// it's ok to use an insecure hash here because
// if someone can change the emit source then they
// can also change the version hash
FastInsecureHasher::new()
.write(bytes)
// emit should not be re-used between cli versions
.write(cli_version.as_bytes())
.finish()
.to_string()
}
#[cfg(test)]
mod test {
use test_util::TempDir;
use super::*;
#[test]
pub fn emit_cache_general_use() {
let temp_dir = TempDir::new();
let disk_cache = DiskCache::new(temp_dir.path());
let cache = EmitCache {
disk_cache: disk_cache.clone(),
cli_version: "1.0.0".to_string(),
};
let specifier1 =
ModuleSpecifier::from_file_path(temp_dir.path().join("file1.ts"))
.unwrap();
let specifier2 =
ModuleSpecifier::from_file_path(temp_dir.path().join("file2.ts"))
.unwrap();
assert_eq!(cache.get_emit_code(&specifier1, 1), None);
let emit_code1 = "text1".to_string();
let emit_code2 = "text2".to_string();
cache.set_emit_code(&specifier1, 10, &emit_code1);
cache.set_emit_code(&specifier2, 2, &emit_code2);
// providing the incorrect source hash
assert_eq!(cache.get_emit_code(&specifier1, 5), None);
// providing the correct source hash
assert_eq!(
cache.get_emit_code(&specifier1, 10),
Some(emit_code1.clone()),
);
assert_eq!(cache.get_emit_code(&specifier2, 2), Some(emit_code2));
// try changing the cli version (should not load previous ones)
let cache = EmitCache {
disk_cache: disk_cache.clone(),
cli_version: "2.0.0".to_string(),
};
assert_eq!(cache.get_emit_code(&specifier1, 10), None);
cache.set_emit_code(&specifier1, 5, &emit_code1);
// recreating the cache should still load the data because the CLI version is the same
let cache = EmitCache {
disk_cache,
cli_version: "2.0.0".to_string(),
};
assert_eq!(cache.get_emit_code(&specifier1, 5), Some(emit_code1));
// adding when already exists should not cause issue
let emit_code3 = "asdf".to_string();
cache.set_emit_code(&specifier1, 20, &emit_code3);
assert_eq!(cache.get_emit_code(&specifier1, 5), None);
assert_eq!(cache.get_emit_code(&specifier1, 20), Some(emit_code3));
}
}