lix/src/libstore/nar-info-disk-cache.cc
John Ericson c51d554c93 Use "raw pattern" for content address types
We weren't because this ancient PR predated it!

This is actually a new version of the pattern which addresses some
issues identified in #7479.
2023-03-30 17:12:49 -04:00

400 lines
13 KiB
C++

#include "nar-info-disk-cache.hh"
#include "sync.hh"
#include "sqlite.hh"
#include "globals.hh"
#include <sqlite3.h>
#include <nlohmann/json.hpp>
namespace nix {
static const char * schema = R"sql(
create table if not exists BinaryCaches (
id integer primary key autoincrement not null,
url text unique not null,
timestamp integer not null,
storeDir text not null,
wantMassQuery integer not null,
priority integer not null
);
create table if not exists NARs (
cache integer not null,
hashPart text not null,
namePart text,
url text,
compression text,
fileHash text,
fileSize integer,
narHash text,
narSize integer,
refs text,
deriver text,
sigs text,
ca text,
timestamp integer not null,
present integer not null,
primary key (cache, hashPart),
foreign key (cache) references BinaryCaches(id) on delete cascade
);
create table if not exists Realisations (
cache integer not null,
outputId text not null,
content blob, -- Json serialisation of the realisation, or null if the realisation is absent
timestamp integer not null,
primary key (cache, outputId),
foreign key (cache) references BinaryCaches(id) on delete cascade
);
create table if not exists LastPurge (
dummy text primary key,
value integer
);
)sql";
class NarInfoDiskCacheImpl : public NarInfoDiskCache
{
public:
/* How often to purge expired entries from the cache. */
const int purgeInterval = 24 * 3600;
/* How long to cache binary cache info (i.e. /nix-cache-info) */
const int cacheInfoTtl = 7 * 24 * 3600;
struct Cache
{
int id;
Path storeDir;
bool wantMassQuery;
int priority;
};
struct State
{
SQLite db;
SQLiteStmt insertCache, queryCache, insertNAR, insertMissingNAR,
queryNAR, insertRealisation, insertMissingRealisation,
queryRealisation, purgeCache;
std::map<std::string, Cache> caches;
};
Sync<State> _state;
NarInfoDiskCacheImpl(Path dbPath = getCacheDir() + "/nix/binary-cache-v6.sqlite")
{
auto state(_state.lock());
createDirs(dirOf(dbPath));
state->db = SQLite(dbPath);
state->db.isCache();
state->db.exec(schema);
state->insertCache.create(state->db,
"insert into BinaryCaches(url, timestamp, storeDir, wantMassQuery, priority) values (?1, ?2, ?3, ?4, ?5) on conflict (url) do update set timestamp = ?2, storeDir = ?3, wantMassQuery = ?4, priority = ?5 returning id;");
state->queryCache.create(state->db,
"select id, storeDir, wantMassQuery, priority from BinaryCaches where url = ? and timestamp > ?");
state->insertNAR.create(state->db,
"insert or replace into NARs(cache, hashPart, namePart, url, compression, fileHash, fileSize, narHash, "
"narSize, refs, deriver, sigs, ca, timestamp, present) values (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, 1)");
state->insertMissingNAR.create(state->db,
"insert or replace into NARs(cache, hashPart, timestamp, present) values (?, ?, ?, 0)");
state->queryNAR.create(state->db,
"select present, namePart, url, compression, fileHash, fileSize, narHash, narSize, refs, deriver, sigs, ca from NARs where cache = ? and hashPart = ? and ((present = 0 and timestamp > ?) or (present = 1 and timestamp > ?))");
state->insertRealisation.create(state->db,
R"(
insert or replace into Realisations(cache, outputId, content, timestamp)
values (?, ?, ?, ?)
)");
state->insertMissingRealisation.create(state->db,
R"(
insert or replace into Realisations(cache, outputId, timestamp)
values (?, ?, ?)
)");
state->queryRealisation.create(state->db,
R"(
select content from Realisations
where cache = ? and outputId = ? and
((content is null and timestamp > ?) or
(content is not null and timestamp > ?))
)");
/* Periodically purge expired entries from the database. */
retrySQLite<void>([&]() {
auto now = time(0);
SQLiteStmt queryLastPurge(state->db, "select value from LastPurge");
auto queryLastPurge_(queryLastPurge.use());
if (!queryLastPurge_.next() || queryLastPurge_.getInt(0) < now - purgeInterval) {
SQLiteStmt(state->db,
"delete from NARs where ((present = 0 and timestamp < ?) or (present = 1 and timestamp < ?))")
.use()
// Use a minimum TTL to prevent --refresh from
// nuking the entire disk cache.
(now - std::max(settings.ttlNegativeNarInfoCache.get(), 3600U))
(now - std::max(settings.ttlPositiveNarInfoCache.get(), 30 * 24 * 3600U))
.exec();
debug("deleted %d entries from the NAR info disk cache", sqlite3_changes(state->db));
SQLiteStmt(state->db,
"insert or replace into LastPurge(dummy, value) values ('', ?)")
.use()(now).exec();
}
});
}
Cache & getCache(State & state, const std::string & uri)
{
auto i = state.caches.find(uri);
if (i == state.caches.end()) abort();
return i->second;
}
private:
std::optional<Cache> queryCacheRaw(State & state, const std::string & uri)
{
auto i = state.caches.find(uri);
if (i == state.caches.end()) {
auto queryCache(state.queryCache.use()(uri)(time(0) - cacheInfoTtl));
if (!queryCache.next())
return std::nullopt;
auto cache = Cache {
.id = (int) queryCache.getInt(0),
.storeDir = queryCache.getStr(1),
.wantMassQuery = queryCache.getInt(2) != 0,
.priority = (int) queryCache.getInt(3),
};
state.caches.emplace(uri, cache);
}
return getCache(state, uri);
}
public:
int createCache(const std::string & uri, const Path & storeDir, bool wantMassQuery, int priority) override
{
return retrySQLite<int>([&]() {
auto state(_state.lock());
SQLiteTxn txn(state->db);
// To avoid the race, we have to check if maybe someone hasn't yet created
// the cache for this URI in the meantime.
auto cache(queryCacheRaw(*state, uri));
if (cache)
return cache->id;
Cache ret {
.id = -1, // set below
.storeDir = storeDir,
.wantMassQuery = wantMassQuery,
.priority = priority,
};
{
auto r(state->insertCache.use()(uri)(time(0))(storeDir)(wantMassQuery)(priority));
assert(r.next());
ret.id = (int) r.getInt(0);
}
state->caches[uri] = ret;
txn.commit();
return ret.id;
});
}
std::optional<CacheInfo> upToDateCacheExists(const std::string & uri) override
{
return retrySQLite<std::optional<CacheInfo>>([&]() -> std::optional<CacheInfo> {
auto state(_state.lock());
auto cache(queryCacheRaw(*state, uri));
if (!cache)
return std::nullopt;
return CacheInfo {
.id = cache->id,
.wantMassQuery = cache->wantMassQuery,
.priority = cache->priority
};
});
}
std::pair<Outcome, std::shared_ptr<NarInfo>> lookupNarInfo(
const std::string & uri, const std::string & hashPart) override
{
return retrySQLite<std::pair<Outcome, std::shared_ptr<NarInfo>>>(
[&]() -> std::pair<Outcome, std::shared_ptr<NarInfo>> {
auto state(_state.lock());
auto & cache(getCache(*state, uri));
auto now = time(0);
auto queryNAR(state->queryNAR.use()
(cache.id)
(hashPart)
(now - settings.ttlNegativeNarInfoCache)
(now - settings.ttlPositiveNarInfoCache));
if (!queryNAR.next())
return {oUnknown, 0};
if (!queryNAR.getInt(0))
return {oInvalid, 0};
auto namePart = queryNAR.getStr(1);
auto narInfo = make_ref<NarInfo>(
StorePath(hashPart + "-" + namePart),
Hash::parseAnyPrefixed(queryNAR.getStr(6)));
narInfo->url = queryNAR.getStr(2);
narInfo->compression = queryNAR.getStr(3);
if (!queryNAR.isNull(4))
narInfo->fileHash = Hash::parseAnyPrefixed(queryNAR.getStr(4));
narInfo->fileSize = queryNAR.getInt(5);
narInfo->narSize = queryNAR.getInt(7);
for (auto & r : tokenizeString<Strings>(queryNAR.getStr(8), " "))
narInfo->references.insert(StorePath(r));
if (!queryNAR.isNull(9))
narInfo->deriver = StorePath(queryNAR.getStr(9));
for (auto & sig : tokenizeString<Strings>(queryNAR.getStr(10), " "))
narInfo->sigs.insert(sig);
narInfo->ca = ContentAddress::parseOpt(queryNAR.getStr(11));
return {oValid, narInfo};
});
}
std::pair<Outcome, std::shared_ptr<Realisation>> lookupRealisation(
const std::string & uri, const DrvOutput & id) override
{
return retrySQLite<std::pair<Outcome, std::shared_ptr<Realisation>>>(
[&]() -> std::pair<Outcome, std::shared_ptr<Realisation>> {
auto state(_state.lock());
auto & cache(getCache(*state, uri));
auto now = time(0);
auto queryRealisation(state->queryRealisation.use()
(cache.id)
(id.to_string())
(now - settings.ttlNegativeNarInfoCache)
(now - settings.ttlPositiveNarInfoCache));
if (!queryRealisation.next())
return {oUnknown, 0};
if (queryRealisation.isNull(0))
return {oInvalid, 0};
auto realisation =
std::make_shared<Realisation>(Realisation::fromJSON(
nlohmann::json::parse(queryRealisation.getStr(0)),
"Local disk cache"));
return {oValid, realisation};
});
}
void upsertNarInfo(
const std::string & uri, const std::string & hashPart,
std::shared_ptr<const ValidPathInfo> info) override
{
retrySQLite<void>([&]() {
auto state(_state.lock());
auto & cache(getCache(*state, uri));
if (info) {
auto narInfo = std::dynamic_pointer_cast<const NarInfo>(info);
//assert(hashPart == storePathToHash(info->path));
state->insertNAR.use()
(cache.id)
(hashPart)
(std::string(info->path.name()))
(narInfo ? narInfo->url : "", narInfo != 0)
(narInfo ? narInfo->compression : "", narInfo != 0)
(narInfo && narInfo->fileHash ? narInfo->fileHash->to_string(Base32, true) : "", narInfo && narInfo->fileHash)
(narInfo ? narInfo->fileSize : 0, narInfo != 0 && narInfo->fileSize)
(info->narHash.to_string(Base32, true))
(info->narSize)
(concatStringsSep(" ", info->shortRefs()))
(info->deriver ? std::string(info->deriver->to_string()) : "", (bool) info->deriver)
(concatStringsSep(" ", info->sigs))
(renderContentAddress(info->ca))
(time(0)).exec();
} else {
state->insertMissingNAR.use()
(cache.id)
(hashPart)
(time(0)).exec();
}
});
}
void upsertRealisation(
const std::string & uri,
const Realisation & realisation) override
{
retrySQLite<void>([&]() {
auto state(_state.lock());
auto & cache(getCache(*state, uri));
state->insertRealisation.use()
(cache.id)
(realisation.id.to_string())
(realisation.toJSON().dump())
(time(0)).exec();
});
}
virtual void upsertAbsentRealisation(
const std::string & uri,
const DrvOutput & id) override
{
retrySQLite<void>([&]() {
auto state(_state.lock());
auto & cache(getCache(*state, uri));
state->insertMissingRealisation.use()
(cache.id)
(id.to_string())
(time(0)).exec();
});
}
};
ref<NarInfoDiskCache> getNarInfoDiskCache()
{
static ref<NarInfoDiskCache> cache = make_ref<NarInfoDiskCacheImpl>();
return cache;
}
ref<NarInfoDiskCache> getTestNarInfoDiskCache(Path dbPath)
{
return make_ref<NarInfoDiskCacheImpl>(dbPath);
}
}