#include "libstore/binary-cache-store.hh"
#include <chrono>
#include <future>
#include <memory>
#include <absl/strings/ascii.h>
#include <absl/strings/numbers.h>
#include <absl/strings/str_split.h>
#include <glog/logging.h>
#include "libstore/derivations.hh"
#include "libstore/fs-accessor.hh"
#include "libstore/globals.hh"
#include "libstore/nar-accessor.hh"
#include "libstore/nar-info-disk-cache.hh"
#include "libstore/nar-info.hh"
#include "libstore/remote-fs-accessor.hh"
#include "libutil/archive.hh"
#include "libutil/compression.hh"
#include "libutil/json.hh"
#include "libutil/sync.hh"
namespace nix {
BinaryCacheStore::BinaryCacheStore(const Params& params) : Store(params) {
if (secretKeyFile != "") {
const std::string& secret_key_file = secretKeyFile;
secretKey = std::make_unique<SecretKey>(readFile(secret_key_file));
}
StringSink sink;
sink << std::string(kNarVersionMagic1);
narMagic = *sink.s;
}
void BinaryCacheStore::init() {
std::string cacheInfoFile = "nix-cache-info";
auto cacheInfo = getFile(cacheInfoFile);
if (!cacheInfo) {
upsertFile(cacheInfoFile, "StoreDir: " + storeDir + "\n",
"text/x-nix-cache-info");
} else {
for (auto& line :
absl::StrSplit(*cacheInfo, absl::ByChar('\n'), absl::SkipEmpty())) {
size_t colon = line.find(':');
if (colon == std::string::npos) {
continue;
}
auto name = line.substr(0, colon);
auto value =
absl::StripAsciiWhitespace(line.substr(colon + 1, std::string::npos));
if (name == "StoreDir") {
if (value != storeDir) {
throw Error(format("binary cache '%s' is for Nix stores with prefix "
"'%s', not '%s'") %
getUri() % value % storeDir);
}
} else if (name == "WantMassQuery") {
wantMassQuery_ = value == "1";
} else if (name == "Priority") {
if (!absl::SimpleAtoi(value, &priority)) {
LOG(WARNING) << "Invalid 'Priority' value: " << value;
}
}
}
}
}
void BinaryCacheStore::getFile(
const std::string& path,
Callback<std::shared_ptr<std::string>> callback) noexcept {
try {
callback(getFile(path));
} catch (...) {
callback.rethrow();
}
}
void BinaryCacheStore::getFile(const std::string& path, Sink& sink) {
std::promise<std::shared_ptr<std::string>> promise;
getFile(path, Callback<std::shared_ptr<std::string>>{
[&](std::future<std::shared_ptr<std::string>> result) {
try {
promise.set_value(result.get());
} catch (...) {
promise.set_exception(std::current_exception());
}
}});
auto data = promise.get_future().get();
sink(reinterpret_cast<unsigned char*>(data->data()), data->size());
}
std::shared_ptr<std::string> BinaryCacheStore::getFile(
const std::string& path) {
StringSink sink;
try {
getFile(path, sink);
} catch (NoSuchBinaryCacheFile&) {
return nullptr;
}
return sink.s;
}
Path BinaryCacheStore::narInfoFileFor(const Path& storePath) {
assertStorePath(storePath);
return storePathToHash(storePath) + ".narinfo";
}
void BinaryCacheStore::writeNarInfo(const ref<NarInfo>& narInfo) {
auto narInfoFile = narInfoFileFor(narInfo->path);
upsertFile(narInfoFile, narInfo->to_string(), "text/x-nix-narinfo");
auto hashPart = storePathToHash(narInfo->path);
{
auto state_(state.lock());
state_->pathInfoCache.upsert(hashPart, std::shared_ptr<NarInfo>(narInfo));
}
if (diskCache) {
diskCache->upsertNarInfo(getUri(), hashPart,
std::shared_ptr<NarInfo>(narInfo));
}
}
void BinaryCacheStore::addToStore(const ValidPathInfo& info,
const ref<std::string>& nar,
RepairFlag repair, CheckSigsFlag checkSigs,
std::shared_ptr<FSAccessor> accessor) {
if ((repair == 0u) && isValidPath(info.path)) {
return;
}
/* Verify that all references are valid. This may do some .narinfo
reads, but typically they'll already be cached. */
for (auto& ref : info.references) {
try {
if (ref != info.path) {
queryPathInfo(ref);
}
} catch (InvalidPath&) {
throw Error(format("cannot add '%s' to the binary cache because the "
"reference '%s' is not valid") %
info.path % ref);
}
}
assert(nar->compare(0, narMagic.size(), narMagic) == 0);
auto narInfo = make_ref<NarInfo>(info);
narInfo->narSize = nar->size();
narInfo->narHash = hashString(htSHA256, *nar);
if (info.narHash && info.narHash != narInfo->narHash) {
throw Error(
format("refusing to copy corrupted path '%1%' to binary cache") %
info.path);
}
auto accessor_ = std::dynamic_pointer_cast<RemoteFSAccessor>(accessor);
/* Optionally write a JSON file containing a listing of the
contents of the NAR. */
if (writeNARListing) {
std::ostringstream jsonOut;
{
JSONObject jsonRoot(jsonOut);
jsonRoot.attr("version", 1);
auto narAccessor = makeNarAccessor(nar);
if (accessor_) {
accessor_->addToCache(info.path, *nar, narAccessor);
}
{
auto res = jsonRoot.placeholder("root");
listNar(res, narAccessor, "", true);
}
}
upsertFile(storePathToHash(info.path) + ".ls", jsonOut.str(),
"application/json");
}
else {
if (accessor_) {
accessor_->addToCache(info.path, *nar, makeNarAccessor(nar));
}
}
/* Compress the NAR. */
narInfo->compression = compression;
auto now1 = std::chrono::steady_clock::now();
auto narCompressed = compress(compression, *nar, parallelCompression);
auto now2 = std::chrono::steady_clock::now();
narInfo->fileHash = hashString(htSHA256, *narCompressed);
narInfo->fileSize = narCompressed->size();
auto duration =
std::chrono::duration_cast<std::chrono::milliseconds>(now2 - now1)
.count();
DLOG(INFO) << "copying path '" << narInfo->path << "' (" << narInfo->narSize
<< " bytes, compressed "
<< ((1.0 -
static_cast<double>(narCompressed->size()) / nar->size()) *
100.0)
<< "% in " << duration << "ms) to binary cache";
/* Atomically write the NAR file. */
narInfo->url = "nar/" + narInfo->fileHash.to_string(Base32, false) + ".nar" +
(compression == "xz" ? ".xz"
: compression == "bzip2"
? ".bz2"
: compression == "br" ? ".br" : "");
if ((repair != 0u) || !fileExists(narInfo->url)) {
stats.narWrite++;
upsertFile(narInfo->url, *narCompressed, "application/x-nix-nar");
} else {
stats.narWriteAverted++;
}
stats.narWriteBytes += nar->size();
stats.narWriteCompressedBytes += narCompressed->size();
stats.narWriteCompressionTimeMs += duration;
/* Atomically write the NAR info file.*/
if (secretKey) {
narInfo->sign(*secretKey);
}
writeNarInfo(narInfo);
stats.narInfoWrite++;
}
bool BinaryCacheStore::isValidPathUncached(const Path& storePath) {
// FIXME: this only checks whether a .narinfo with a matching hash
// part exists. So ‘f4kb...-foo’ matches ‘f4kb...-bar’, even
// though they shouldn't. Not easily fixed.
return fileExists(narInfoFileFor(storePath));
}
void BinaryCacheStore::narFromPath(const Path& storePath, Sink& sink) {
auto info = queryPathInfo(storePath).cast<const NarInfo>();
uint64_t narSize = 0;
LambdaSink wrapperSink([&](const unsigned char* data, size_t len) {
sink(data, len);
narSize += len;
});
auto decompressor = makeDecompressionSink(info->compression, wrapperSink);
try {
getFile(info->url, *decompressor);
} catch (NoSuchBinaryCacheFile& e) {
throw SubstituteGone(e.what());
}
decompressor->finish();
stats.narRead++;
// stats.narReadCompressedBytes += nar->size(); // FIXME
stats.narReadBytes += narSize;
}
void BinaryCacheStore::queryPathInfoUncached(
const Path& storePath,
Callback<std::shared_ptr<ValidPathInfo>> callback) noexcept {
auto uri = getUri();
LOG(INFO) << "querying info about '" << storePath << "' on '" << uri << "'";
auto narInfoFile = narInfoFileFor(storePath);
auto callbackPtr = std::make_shared<decltype(callback)>(std::move(callback));
getFile(narInfoFile,
Callback<std::shared_ptr<std::string>>(
[=](std::future<std::shared_ptr<std::string>> fut) {
try {
auto data = fut.get();
if (!data) {
return (*callbackPtr)(nullptr);
}
stats.narInfoRead++;
(*callbackPtr)(std::shared_ptr<ValidPathInfo>(
std::make_shared<NarInfo>(*this, *data, narInfoFile)));
} catch (...) {
callbackPtr->rethrow();
}
}));
}
Path BinaryCacheStore::addToStore(const std::string& name, const Path& srcPath,
bool recursive, HashType hashAlgo,
PathFilter& filter, RepairFlag repair) {
// FIXME: some cut&paste from LocalStore::addToStore().
/* Read the whole path into memory. This is not a very scalable
method for very large paths, but `copyPath' is mainly used for
small files. */
StringSink sink;
Hash h;
if (recursive) {
dumpPath(srcPath, sink, filter);
h = hashString(hashAlgo, *sink.s);
} else {
auto s = readFile(srcPath);
dumpString(s, sink);
h = hashString(hashAlgo, s);
}
ValidPathInfo info;
info.path = makeFixedOutputPath(recursive, h, name);
addToStore(info, sink.s, repair, CheckSigs, nullptr);
return info.path;
}
Path BinaryCacheStore::addTextToStore(const std::string& name,
const std::string& s,
const PathSet& references,
RepairFlag repair) {
ValidPathInfo info;
info.path = computeStorePathForText(name, s, references);
info.references = references;
if ((repair != 0u) || !isValidPath(info.path)) {
StringSink sink;
dumpString(s, sink);
addToStore(info, sink.s, repair, CheckSigs, nullptr);
}
return info.path;
}
ref<FSAccessor> BinaryCacheStore::getFSAccessor() {
return make_ref<RemoteFSAccessor>(ref<Store>(shared_from_this()),
localNarCache);
}
void BinaryCacheStore::addSignatures(const Path& storePath,
const StringSet& sigs) {
/* Note: this is inherently racy since there is no locking on
binary caches. In particular, with S3 this unreliable, even
when addSignatures() is called sequentially on a path, because
S3 might return an outdated cached version. */
auto narInfo = make_ref<NarInfo>((NarInfo&)*queryPathInfo(storePath));
narInfo->sigs.insert(sigs.begin(), sigs.end());
auto narInfoFile = narInfoFileFor(narInfo->path);
writeNarInfo(narInfo);
}
std::shared_ptr<std::string> BinaryCacheStore::getBuildLog(const Path& path) {
Path drvPath;
if (isDerivation(path)) {
drvPath = path;
} else {
try {
auto info = queryPathInfo(path);
// FIXME: add a "Log" field to .narinfo
if (info->deriver.empty()) {
return nullptr;
}
drvPath = info->deriver;
} catch (InvalidPath&) {
return nullptr;
}
}
auto logPath = "log/" + baseNameOf(drvPath);
DLOG(INFO) << "fetching build log from binary cache '" << getUri() << "/"
<< logPath << "'";
return getFile(logPath);
}
} // namespace nix
