Add basic flake lock file support

This commit is contained in:
Eelco Dolstra 2019-02-12 22:43:22 +01:00
parent e38ec77de8
commit 6e9182fbc2
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GPG key ID: 8170B4726D7198DE

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@ -10,31 +10,40 @@
namespace nix {
/* Read the registry or a lock file. (Currently they have an identical
format. */
static std::unique_ptr<FlakeRegistry> readRegistry(const Path & path)
{
auto registry = std::make_unique<FlakeRegistry>();
auto json = nlohmann::json::parse(readFile(path));
auto version = json.value("version", 0);
if (version != 1)
throw Error("flake registry '%s' has unsupported version %d", path, version);
auto flakes = json["flakes"];
for (auto i = flakes.begin(); i != flakes.end(); ++i) {
FlakeRegistry::Entry entry{FlakeRef(i->value("uri", ""))};
registry->entries.emplace(i.key(), entry);
}
return registry;
}
const FlakeRegistry & EvalState::getFlakeRegistry()
{
std::call_once(_flakeRegistryInit, [&]()
{
_flakeRegistry = std::make_unique<FlakeRegistry>();
#if 0
auto registryUri = "file:///home/eelco/Dev/gists/nix-flakes/registry.json";
auto registryFile = getDownloader()->download(DownloadRequest(registryUri));
#endif
auto registryFile = readFile(settings.nixDataDir + "/nix/flake-registry.json");
auto registryFile = settings.nixDataDir + "/nix/flake-registry.json";
auto json = nlohmann::json::parse(registryFile);
auto version = json.value("version", 0);
if (version != 1)
throw Error("flake registry '%s' has unsupported version %d", registryFile, version);
auto flakes = json["flakes"];
for (auto i = flakes.begin(); i != flakes.end(); ++i) {
FlakeRegistry::Entry entry{FlakeRef(i->value("uri", ""))};
_flakeRegistry->entries.emplace(i.key(), entry);
}
_flakeRegistry = readRegistry(registryFile);
});
return *_flakeRegistry;
@ -60,33 +69,24 @@ Value * makeFlakeRegistryValue(EvalState & state)
return v;
}
static FlakeRef lookupFlake(EvalState & state, const FlakeRef & flakeRef)
static FlakeRef lookupFlake(EvalState & state, const FlakeRef & flakeRef,
std::vector<const FlakeRegistry *> registries)
{
if (auto refData = std::get_if<FlakeRef::IsFlakeId>(&flakeRef.data)) {
auto registry = state.getFlakeRegistry();
auto i = registry.entries.find(refData->id);
if (i == registry.entries.end())
throw Error("cannot find flake '%s' in the flake registry", refData->id);
for (auto registry : registries) {
auto i = registry->entries.find(refData->id);
if (i != registry->entries.end()) {
auto newRef = FlakeRef(i->second.ref);
if (!newRef.isDirect())
throw Error("found indirect flake URI '%s' in the flake registry", i->second.ref.to_string());
return newRef;
}
}
throw Error("cannot find flake '%s' in the flake registry or in the flake lock file", refData->id);
} else
return flakeRef;
}
struct Flake
{
FlakeId id;
std::string description;
Path path;
std::set<std::string> requires;
Value * vProvides; // FIXME: gc
// commit hash
// date
// content hash
};
static Path fetchFlake(EvalState & state, const FlakeRef & flakeRef)
{
assert(flakeRef.isDirect());
@ -123,6 +123,19 @@ static Path fetchFlake(EvalState & state, const FlakeRef & flakeRef)
else abort();
}
struct Flake
{
FlakeId id;
std::string description;
Path path;
std::vector<FlakeRef> requires;
std::unique_ptr<FlakeRegistry> lockFile;
Value * vProvides; // FIXME: gc
// commit hash
// date
// content hash
};
static Flake getFlake(EvalState & state, const FlakeRef & flakeRef)
{
auto flakePath = fetchFlake(state, flakeRef);
@ -134,7 +147,7 @@ static Flake getFlake(EvalState & state, const FlakeRef & flakeRef)
Flake flake;
Value vInfo;
state.evalFile(flakePath + "/flake.nix", vInfo);
state.evalFile(flakePath + "/flake.nix", vInfo); // FIXME: symlink attack
state.forceAttrs(vInfo);
@ -149,8 +162,8 @@ static Flake getFlake(EvalState & state, const FlakeRef & flakeRef)
if (auto requires = vInfo.attrs->get(state.symbols.create("requires"))) {
state.forceList(*(**requires).value, *(**requires).pos);
for (unsigned int n = 0; n < (**requires).value->listSize(); ++n)
flake.requires.insert(state.forceStringNoCtx(
*(**requires).value->listElems()[n], *(**requires).pos));
flake.requires.push_back(FlakeRef(state.forceStringNoCtx(
*(**requires).value->listElems()[n], *(**requires).pos)));
}
if (auto provides = vInfo.attrs->get(state.symbols.create("provides"))) {
@ -159,6 +172,16 @@ static Flake getFlake(EvalState & state, const FlakeRef & flakeRef)
} else
throw Error("flake lacks attribute 'provides'");
auto lockFile = flakePath + "/flake.lock"; // FIXME: symlink attack
if (pathExists(lockFile)) {
flake.lockFile = readRegistry(lockFile);
for (auto & entry : flake.lockFile->entries)
if (!entry.second.ref.isImmutable())
throw Error("flake lock file '%s' contains mutable entry '%s'",
lockFile, entry.second.ref.to_string());
}
return flake;
}
@ -174,13 +197,19 @@ static std::tuple<FlakeId, std::map<FlakeId, Flake>> resolveFlake(EvalState & st
std::optional<FlakeId> topFlakeId; /// FIXME: ambiguous
todo.push({topRef, true});
std::vector<const FlakeRegistry *> registries;
FlakeRegistry localRegistry;
registries.push_back(&localRegistry);
if (!evalSettings.pureEval)
registries.push_back(&state.getFlakeRegistry());
while (!todo.empty()) {
auto [flakeRef, toplevel] = todo.front();
todo.pop();
if (auto refData = std::get_if<FlakeRef::IsFlakeId>(&flakeRef.data)) {
if (done.count(refData->id)) continue; // optimization
flakeRef = lookupFlake(state, flakeRef);
flakeRef = lookupFlake(state, flakeRef, registries);
}
if (evalSettings.pureEval && !flakeRef.isImmutable() && (!toplevel || !impureTopRef))
@ -195,11 +224,17 @@ static std::tuple<FlakeId, std::map<FlakeId, Flake>> resolveFlake(EvalState & st
for (auto & require : flake.requires)
todo.push({require, false});
done.emplace(flake.id, flake);
if (flake.lockFile)
for (auto & entry : flake.lockFile->entries) {
if (localRegistry.entries.count(entry.first)) continue;
localRegistry.entries.emplace(entry.first, entry.second);
}
done.emplace(flake.id, std::move(flake));
}
assert(topFlakeId);
return {*topFlakeId, done};
return {*topFlakeId, std::move(done)};
}
Value * makeFlakeValue(EvalState & state, std::string flakeUri, Value & v)