lix/src/nix/installables.cc
Matthew Kenigsberg 9f4cfbb2e7 Refactor installables
InstallableValue has children InstallableFlake and InstallableAttrPath, but InstallableFlake was overriding toDerivations, and usage was changed so that InstallableFlake didn't need cmd. So these changes were made:
InstallableValue::toDerivations() -> InstalllableAttrPath::toDerivations()
InstallableValue::cmd -> InstallableAttrPath::cmd

InstallableValue uses state instead of cmd

toBuildables() and toDerivations() were made abstract
2020-05-09 14:42:32 -06:00

569 lines
17 KiB
C++

#include "installables.hh"
#include "command.hh"
#include "attr-path.hh"
#include "common-eval-args.hh"
#include "derivations.hh"
#include "eval-inline.hh"
#include "eval.hh"
#include "get-drvs.hh"
#include "store-api.hh"
#include "shared.hh"
#include "flake/flake.hh"
#include "eval-cache.hh"
#include "url.hh"
#include <regex>
#include <queue>
namespace nix {
MixFlakeOptions::MixFlakeOptions()
{
addFlag({
.longName = "recreate-lock-file",
.description = "recreate lock file from scratch",
.handler = {&lockFlags.recreateLockFile, true}
});
addFlag({
.longName = "no-update-lock-file",
.description = "do not allow any updates to the lock file",
.handler = {&lockFlags.updateLockFile, false}
});
addFlag({
.longName = "no-write-lock-file",
.description = "do not write the newly generated lock file",
.handler = {&lockFlags.writeLockFile, false}
});
addFlag({
.longName = "no-registries",
.description = "don't use flake registries",
.handler = {&lockFlags.useRegistries, false}
});
addFlag({
.longName = "commit-lock-file",
.description = "commit changes to the lock file",
.handler = {&lockFlags.commitLockFile, true}
});
addFlag({
.longName = "update-input",
.description = "update a specific flake input",
.labels = {"input-path"},
.handler = {[&](std::string s) {
lockFlags.inputUpdates.insert(flake::parseInputPath(s));
}}
});
addFlag({
.longName = "override-input",
.description = "override a specific flake input (e.g. 'dwarffs/nixpkgs')",
.labels = {"input-path", "flake-url"},
.handler = {[&](std::string inputPath, std::string flakeRef) {
lockFlags.inputOverrides.insert_or_assign(
flake::parseInputPath(inputPath),
parseFlakeRef(flakeRef, absPath(".")));
}}
});
}
SourceExprCommand::SourceExprCommand()
{
addFlag({
.longName = "file",
.shortName = 'f',
.description = "evaluate FILE rather than the default",
.labels = {"file"},
.handler = {&file}
});
addFlag({
.longName ="expr",
.description = "evaluate attributes from EXPR",
.labels = {"expr"},
.handler = {&expr}
});
}
Strings SourceExprCommand::getDefaultFlakeAttrPaths()
{
return {"defaultPackage." + settings.thisSystem.get()};
}
Strings SourceExprCommand::getDefaultFlakeAttrPathPrefixes()
{
return {
// As a convenience, look for the attribute in
// 'outputs.packages'.
"packages." + settings.thisSystem.get() + ".",
// As a temporary hack until Nixpkgs is properly converted
// to provide a clean 'packages' set, look in 'legacyPackages'.
"legacyPackages." + settings.thisSystem.get() + "."
};
}
ref<EvalState> EvalCommand::getEvalState()
{
if (!evalState)
evalState = std::make_shared<EvalState>(searchPath, getStore());
return ref<EvalState>(evalState);
}
Buildable Installable::toBuildable()
{
auto buildables = toBuildables();
if (buildables.size() != 1)
throw Error("installable '%s' evaluates to %d derivations, where only one is expected", what(), buildables.size());
return std::move(buildables[0]);
}
App::App(EvalState & state, Value & vApp)
{
state.forceAttrs(vApp);
auto aType = vApp.attrs->need(state.sType);
if (state.forceStringNoCtx(*aType.value, *aType.pos) != "app")
throw Error("value does not have type 'app', at %s", *aType.pos);
auto aProgram = vApp.attrs->need(state.symbols.create("program"));
program = state.forceString(*aProgram.value, context, *aProgram.pos);
// FIXME: check that 'program' is in the closure of 'context'.
if (!state.store->isInStore(program))
throw Error("app program '%s' is not in the Nix store", program);
}
App Installable::toApp(EvalState & state)
{
return App(state, *toValue(state).first);
}
std::vector<std::pair<std::shared_ptr<eval_cache::AttrCursor>, std::string>>
Installable::getCursor(EvalState & state, bool useEvalCache)
{
auto evalCache =
std::make_shared<nix::eval_cache::EvalCache>(false, Hash(), state,
[&]() { return toValue(state).first; });
return {{evalCache->getRoot(), ""}};
}
struct InstallableStorePath : Installable
{
ref<Store> store;
StorePath storePath;
InstallableStorePath(ref<Store> store, const Path & storePath)
: store(store), storePath(store->parseStorePath(storePath)) { }
std::string what() override { return store->printStorePath(storePath); }
Buildables toBuildables() override
{
std::map<std::string, StorePath> outputs;
outputs.insert_or_assign("out", storePath.clone());
Buildable b{
.drvPath = storePath.isDerivation() ? storePath.clone() : std::optional<StorePath>(),
.outputs = std::move(outputs)
};
Buildables bs;
bs.push_back(std::move(b));
return bs;
}
std::optional<StorePath> getStorePath() override
{
return storePath.clone();
}
};
std::vector<InstallableValue::DerivationInfo> InstallableAttrPath::toDerivations()
{
auto v = toValue(*state).first;
Bindings & autoArgs = *cmd.getAutoArgs(*state);
DrvInfos drvInfos;
getDerivations(*state, *v, "", autoArgs, drvInfos, false);
std::vector<DerivationInfo> res;
for (auto & drvInfo : drvInfos) {
res.push_back({
state->store->parseStorePath(drvInfo.queryDrvPath()),
state->store->parseStorePath(drvInfo.queryOutPath()),
drvInfo.queryOutputName()
});
}
return res;
}
Buildables InstallableValue::toBuildables()
{
Buildables res;
StorePathSet drvPaths;
for (auto & drv : toDerivations()) {
Buildable b{.drvPath = drv.drvPath.clone()};
drvPaths.insert(drv.drvPath.clone());
auto outputName = drv.outputName;
if (outputName == "")
throw Error("derivation '%s' lacks an 'outputName' attribute", state->store->printStorePath(*b.drvPath));
b.outputs.emplace(outputName, drv.outPath.clone());
res.push_back(std::move(b));
}
// Hack to recognize .all: if all drvs have the same drvPath,
// merge the buildables.
if (drvPaths.size() == 1) {
Buildable b{.drvPath = drvPaths.begin()->clone()};
for (auto & b2 : res)
for (auto & output : b2.outputs)
b.outputs.insert_or_assign(output.first, output.second.clone());
Buildables bs;
bs.push_back(std::move(b));
return bs;
} else
return res;
}
struct InstallableAttrPath : InstallableValue
{
SourceExprCommand & cmd;
RootValue v;
std::string attrPath;
InstallableAttrPath(ref<EvalState> state, SourceExprCommand & cmd, Value * v, const std::string & attrPath)
: InstallableValue(state), cmd(cmd), v(allocRootValue(v)), attrPath(attrPath)
{ }
std::string what() override { return attrPath; }
std::pair<Value *, Pos> toValue(EvalState & state) override
{
auto [vRes, pos] = findAlongAttrPath(state, attrPath, *cmd.getAutoArgs(state), **v);
state.forceValue(*vRes);
return {vRes, pos};
}
virtual std::vector<InstallableValue::DerivationInfo> toDerivations() override;
};
std::vector<std::string> InstallableFlake::getActualAttrPaths()
{
std::vector<std::string> res;
for (auto & prefix : prefixes)
res.push_back(prefix + *attrPaths.begin());
for (auto & s : attrPaths)
res.push_back(s);
return res;
}
Value * InstallableFlake::getFlakeOutputs(EvalState & state, const flake::LockedFlake & lockedFlake)
{
auto vFlake = state.allocValue();
callFlake(state, lockedFlake, *vFlake);
auto aOutputs = vFlake->attrs->get(state.symbols.create("outputs"));
assert(aOutputs);
state.forceValue(*aOutputs->value);
return aOutputs->value;
}
ref<eval_cache::EvalCache> openEvalCache(
EvalState & state,
std::shared_ptr<flake::LockedFlake> lockedFlake,
bool useEvalCache)
{
return ref(std::make_shared<nix::eval_cache::EvalCache>(
useEvalCache,
lockedFlake->getFingerprint(),
state,
[&state, lockedFlake]()
{
/* For testing whether the evaluation cache is
complete. */
if (getEnv("NIX_ALLOW_EVAL").value_or("1") == "0")
throw Error("not everything is cached, but evaluation is not allowed");
auto vFlake = state.allocValue();
flake::callFlake(state, *lockedFlake, *vFlake);
state.forceAttrs(*vFlake);
auto aOutputs = vFlake->attrs->get(state.symbols.create("outputs"));
assert(aOutputs);
return aOutputs->value;
}));
}
std::tuple<std::string, FlakeRef, InstallableValue::DerivationInfo> InstallableFlake::toDerivation()
{
auto lockedFlake = std::make_shared<flake::LockedFlake>(
lockFlake(*state, flakeRef, lockFlags));
auto cache = openEvalCache(*state, lockedFlake, true);
auto root = cache->getRoot();
for (auto & attrPath : getActualAttrPaths()) {
auto attr = root->findAlongAttrPath(parseAttrPath(*state, attrPath));
if (!attr) continue;
if (!attr->isDerivation())
throw Error("flake output attribute '%s' is not a derivation", attrPath);
auto aDrvPath = attr->getAttr(state->sDrvPath);
auto drvPath = state->store->parseStorePath(aDrvPath->getString());
if (!state->store->isValidPath(drvPath) && !settings.readOnlyMode) {
/* The eval cache contains 'drvPath', but the actual path
has been garbage-collected. So force it to be
regenerated. */
aDrvPath->forceValue();
if (!state->store->isValidPath(drvPath))
throw Error("don't know how to recreate store derivation '%s'!",
state->store->printStorePath(drvPath));
}
auto drvInfo = DerivationInfo{
std::move(drvPath),
state->store->parseStorePath(attr->getAttr(state->sOutPath)->getString()),
attr->getAttr(state->sOutputName)->getString()
};
return {attrPath, lockedFlake->flake.lockedRef, std::move(drvInfo)};
}
throw Error("flake '%s' does not provide attribute %s",
flakeRef, concatStringsSep(", ", quoteStrings(attrPaths)));
}
std::vector<InstallableValue::DerivationInfo> InstallableFlake::toDerivations()
{
std::vector<DerivationInfo> res;
res.push_back(std::get<2>(toDerivation()));
return res;
}
std::pair<Value *, Pos> InstallableFlake::toValue(EvalState & state)
{
auto lockedFlake = lockFlake(state, flakeRef, lockFlags);
auto vOutputs = getFlakeOutputs(state, lockedFlake);
auto emptyArgs = state.allocBindings(0);
for (auto & attrPath : getActualAttrPaths()) {
try {
auto [v, pos] = findAlongAttrPath(state, attrPath, *emptyArgs, *vOutputs);
state.forceValue(*v);
return {v, pos};
} catch (AttrPathNotFound & e) {
}
}
throw Error("flake '%s' does not provide attribute %s",
flakeRef, concatStringsSep(", ", quoteStrings(attrPaths)));
}
std::vector<std::pair<std::shared_ptr<eval_cache::AttrCursor>, std::string>>
InstallableFlake::getCursor(EvalState & state, bool useEvalCache)
{
auto evalCache = openEvalCache(state,
std::make_shared<flake::LockedFlake>(lockFlake(state, flakeRef, lockFlags)),
useEvalCache);
auto root = evalCache->getRoot();
std::vector<std::pair<std::shared_ptr<eval_cache::AttrCursor>, std::string>> res;
for (auto & attrPath : getActualAttrPaths()) {
auto attr = root->findAlongAttrPath(parseAttrPath(state, attrPath));
if (attr) res.push_back({attr, attrPath});
}
return res;
}
std::vector<std::shared_ptr<Installable>> SourceExprCommand::parseInstallables(
ref<Store> store, std::vector<std::string> ss)
{
std::vector<std::shared_ptr<Installable>> result;
if (file || expr) {
if (file && expr)
throw UsageError("'--file' and '--expr' are exclusive");
// FIXME: backward compatibility hack
if (file) evalSettings.pureEval = false;
auto state = getEvalState();
auto vFile = state->allocValue();
if (file)
state->evalFile(lookupFileArg(*state, *file), *vFile);
else {
auto e = state->parseExprFromString(*expr, absPath("."));
state->eval(e, *vFile);
}
for (auto & s : ss)
result.push_back(std::make_shared<InstallableAttrPath>(state, *this, vFile, s == "." ? "" : s));
} else {
for (auto & s : ss) {
std::exception_ptr ex;
try {
auto [flakeRef, fragment] = parseFlakeRefWithFragment(s, absPath("."));
result.push_back(std::make_shared<InstallableFlake>(
getEvalState(), std::move(flakeRef),
fragment == "" ? getDefaultFlakeAttrPaths() : Strings{fragment},
getDefaultFlakeAttrPathPrefixes(), lockFlags));
continue;
} catch (...) {
ex = std::current_exception();
}
if (s.find('/') != std::string::npos) {
try {
result.push_back(std::make_shared<InstallableStorePath>(store, store->printStorePath(store->followLinksToStorePath(s))));
continue;
} catch (NotInStore &) {
} catch (...) {
if (!ex)
ex = std::current_exception();
}
}
std::rethrow_exception(ex);
/*
throw Error(
pathExists(s)
? "path '%s' is not a flake or a store path"
: "don't know how to handle argument '%s'", s);
*/
}
}
return result;
}
std::shared_ptr<Installable> SourceExprCommand::parseInstallable(
ref<Store> store, const std::string & installable)
{
auto installables = parseInstallables(store, {installable});
assert(installables.size() == 1);
return installables.front();
}
Buildables build(ref<Store> store, RealiseMode mode,
std::vector<std::shared_ptr<Installable>> installables)
{
if (mode != Build)
settings.readOnlyMode = true;
Buildables buildables;
std::vector<StorePathWithOutputs> pathsToBuild;
for (auto & i : installables) {
for (auto & b : i->toBuildables()) {
if (b.drvPath) {
StringSet outputNames;
for (auto & output : b.outputs)
outputNames.insert(output.first);
pathsToBuild.push_back({*b.drvPath, outputNames});
} else
for (auto & output : b.outputs)
pathsToBuild.push_back({output.second.clone()});
buildables.push_back(std::move(b));
}
}
if (mode == DryRun)
printMissing(store, pathsToBuild, lvlError);
else if (mode == Build)
store->buildPaths(pathsToBuild);
return buildables;
}
StorePathSet toStorePaths(ref<Store> store, RealiseMode mode,
std::vector<std::shared_ptr<Installable>> installables)
{
StorePathSet outPaths;
for (auto & b : build(store, mode, installables))
for (auto & output : b.outputs)
outPaths.insert(output.second.clone());
return outPaths;
}
StorePath toStorePath(ref<Store> store, RealiseMode mode,
std::shared_ptr<Installable> installable)
{
auto paths = toStorePaths(store, mode, {installable});
if (paths.size() != 1)
throw Error("argument '%s' should evaluate to one store path", installable->what());
return paths.begin()->clone();
}
StorePathSet toDerivations(ref<Store> store,
std::vector<std::shared_ptr<Installable>> installables, bool useDeriver)
{
StorePathSet drvPaths;
for (auto & i : installables)
for (auto & b : i->toBuildables()) {
if (!b.drvPath) {
if (!useDeriver)
throw Error("argument '%s' did not evaluate to a derivation", i->what());
for (auto & output : b.outputs) {
auto derivers = store->queryValidDerivers(output.second);
if (derivers.empty())
throw Error("'%s' does not have a known deriver", i->what());
// FIXME: use all derivers?
drvPaths.insert(derivers.begin()->clone());
}
} else
drvPaths.insert(b.drvPath->clone());
}
return drvPaths;
}
void InstallablesCommand::prepare()
{
if (_installables.empty() && useDefaultInstallables())
// FIXME: commands like "nix install" should not have a
// default, probably.
_installables.push_back(".");
installables = parseInstallables(getStore(), _installables);
}
void InstallableCommand::prepare()
{
installable = parseInstallable(getStore(), _installable);
}
}