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
|
// Copyright 2024 Huawei Cloud Computing Technology Co., Ltd.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#include "src/buildtool/execution_api/utils/rehash_utils.hpp"
#include <concepts>
#include <cstddef> // std::size_t
#include <filesystem>
#include <functional>
#include <system_error>
#include <utility> // std::move
#include <variant>
#include "fmt/core.h"
#include "src/buildtool/crypto/hash_function.hpp"
#include "src/buildtool/execution_api/bazel_msg/bazel_msg_factory.hpp"
#include "src/buildtool/file_system/file_system_manager.hpp"
#include "src/buildtool/storage/fs_utils.hpp"
#include "src/buildtool/storage/storage.hpp"
namespace RehashUtils {
auto ReadRehashedDigest(ArtifactDigest const& digest,
StorageConfig const& source_config,
StorageConfig const& target_config,
bool from_git) noexcept
-> expected<std::optional<Artifact::ObjectInfo>, std::string> {
// check for mapping file in all generations
std::size_t generation = 0;
std::optional<std::filesystem::path> rehash_id_file = std::nullopt;
auto const compat_hash_type = target_config.hash_function.GetType();
for (; generation < source_config.num_generations; ++generation) {
auto path = StorageUtils::GetRehashIDFile(source_config,
compat_hash_type,
digest.hash(),
from_git,
generation);
if (FileSystemManager::Exists(path)) {
rehash_id_file = std::move(path);
break; // found the generation
}
}
if (rehash_id_file) {
// read id file
auto compat_obj_str = FileSystemManager::ReadFile(*rehash_id_file);
if (not compat_obj_str) {
return unexpected{fmt::format("failed to read rehash id file {}",
rehash_id_file->string())};
}
// get artifact object from content
auto compat_obj =
Artifact::ObjectInfo::FromString(compat_hash_type, *compat_obj_str);
if (not compat_obj) {
// handle nullopt value explicitly
return unexpected{
fmt::format("failed to read rehashed artifact from id file {}",
rehash_id_file->string())};
}
// ensure the id file is in generation 0 for future calls
if (generation != 0) {
auto dest_id_file = StorageUtils::GetRehashIDFile(
source_config, compat_hash_type, digest.hash(), from_git);
auto ok = FileSystemManager::CreateFileHardlink(*rehash_id_file,
dest_id_file);
if (not ok) {
auto const& err = ok.error();
if (err != std::errc::too_many_links) {
return unexpected{
fmt::format("failed to link rehash id file {}:\n{} {}",
dest_id_file.string(),
err.value(),
err.message())};
}
// if too many links reported, write id file ourselves
if (not StorageUtils::WriteTreeIDFile(dest_id_file,
*compat_obj_str)) {
return unexpected{
fmt::format("failed to write rehash id file {}",
dest_id_file.string())};
}
}
}
return std::move(compat_obj); // not dereferenced to assist type
// deduction in variant
}
// no mapping file found
return std::optional<Artifact::ObjectInfo>{std::nullopt};
}
auto StoreRehashedDigest(ArtifactDigest const& source_digest,
ArtifactDigest const& target_digest,
ObjectType obj_type,
StorageConfig const& source_config,
StorageConfig const& target_config,
bool from_git) noexcept -> std::optional<std::string> {
// write mapping
auto const rehash_id_file =
StorageUtils::GetRehashIDFile(source_config,
target_config.hash_function.GetType(),
source_digest.hash(),
from_git);
if (not StorageUtils::WriteTreeIDFile(
rehash_id_file,
Artifact::ObjectInfo{.digest = target_digest, .type = obj_type}
.ToString())) {
return fmt::format("failed to write rehash id to file {}",
rehash_id_file.string());
}
return std::nullopt; // a-ok
}
namespace {
template <std::invocable<ArtifactDigest const&, ObjectType> TReadCallback>
[[nodiscard]] auto RehashDigestImpl(
std::vector<Artifact::ObjectInfo> const& infos,
StorageConfig const& source_config,
StorageConfig const& target_config,
TReadCallback read_callback,
bool from_git) -> expected<std::vector<Artifact::ObjectInfo>, std::string> {
auto const target_storage = Storage::Create(&target_config);
BazelMsgFactory::BlobStoreFunc store_file =
[&target_storage](
std::variant<std::filesystem::path, std::string> const& data,
bool is_exec) -> std::optional<ArtifactDigest> {
if (not std::holds_alternative<std::filesystem::path>(data)) {
return std::nullopt;
}
return target_storage.CAS().StoreBlob(
std::get<std::filesystem::path>(data), is_exec);
};
BazelMsgFactory::TreeStoreFunc store_dir =
[&cas = target_storage.CAS()](std::string const& content) {
return cas.StoreTree(content);
};
BazelMsgFactory::SymlinkStoreFunc store_symlink =
[&cas = target_storage.CAS()](std::string const& content) {
return cas.StoreBlob(content);
};
BazelMsgFactory::RehashedDigestReadFunc read_rehashed =
[&source_config, &target_config, from_git](ArtifactDigest const& digest)
-> expected<std::optional<Artifact::ObjectInfo>, std::string> {
return RehashUtils::ReadRehashedDigest(
digest, source_config, target_config, from_git);
};
BazelMsgFactory::RehashedDigestStoreFunc store_rehashed =
[&source_config, &target_config, from_git](
ArtifactDigest const& source_digest,
ArtifactDigest const& target_digest,
ObjectType obj_type) -> std::optional<std::string> {
return RehashUtils::StoreRehashedDigest(source_digest,
target_digest,
obj_type,
source_config,
target_config,
from_git);
};
// collect the native blobs and rehash them as compatible to be able to
// check what is missing in the other api
std::vector<Artifact::ObjectInfo> compat_artifacts;
compat_artifacts.reserve(infos.size());
for (auto const& source_object : infos) {
// check if we know already the compatible digest
auto cached_obj = read_rehashed(source_object.digest);
if (not cached_obj) {
return unexpected(std::move(cached_obj).error());
}
if (*cached_obj) {
// add object to the vector of compatible artifacts
compat_artifacts.emplace_back(std::move(cached_obj)->value());
continue;
}
// process object; trees need to be handled appropriately
if (IsTreeObject(source_object.type)) {
// get the directory digest
auto target_tree =
BazelMsgFactory::CreateDirectoryDigestFromGitTree(
source_object.digest,
read_callback,
store_file,
store_dir,
store_symlink,
read_rehashed,
store_rehashed);
if (not target_tree) {
return unexpected(std::move(target_tree).error());
}
// add object to the vector of compatible artifacts
compat_artifacts.emplace_back(Artifact::ObjectInfo{
.digest = *std::move(target_tree), .type = ObjectType::Tree});
}
else {
// blobs can be directly rehashed
auto path = read_callback(source_object.digest, source_object.type);
if (not path) {
return unexpected(
fmt::format("failed to get path of entry {}",
source_object.digest.hash()));
}
auto target_blob =
store_file(*path, IsExecutableObject(source_object.type));
if (not target_blob) {
return unexpected(fmt::format("failed to rehash entry {}",
source_object.digest.hash()));
}
// cache the digest association
if (auto error_msg = store_rehashed(
source_object.digest, *target_blob, source_object.type)) {
return unexpected(*std::move(error_msg));
}
// add object to the vector of compatible artifacts
compat_artifacts.emplace_back(Artifact::ObjectInfo{
.digest = *std::move(target_blob), .type = source_object.type});
}
}
return compat_artifacts;
}
} // namespace
auto RehashDigest(std::vector<Artifact::ObjectInfo> const& digests,
StorageConfig const& source_config,
StorageConfig const& target_config)
-> expected<std::vector<Artifact::ObjectInfo>, std::string> {
auto const source_storage = Storage::Create(&source_config);
auto read = [&source_storage](
ArtifactDigest const& digest,
ObjectType type) -> std::optional<std::filesystem::path> {
return IsTreeObject(type) ? source_storage.CAS().TreePath(digest)
: source_storage.CAS().BlobPath(
digest, IsExecutableObject(type));
};
return RehashDigestImpl(digests,
source_config,
target_config,
std::move(read),
/*from_git=*/false);
}
} // namespace RehashUtils
|
