nixos/nix
1
1
Fork 0
mirror of https://github.com/NixOS/nix.git synced 2025-11-11 13:06:01 +01:00
Code Activity

Make the Derived Path family of types inductive for dynamic derivations

Browse source 
We want to be able to write down `foo.drv^bar.drv^baz`:
`foo.drv^bar.drv` is the dynamic derivation (since it is itself a
derivation output, `bar.drv` from `foo.drv`).

To that end, we create `Single{Derivation,BuiltPath}` types, that are
very similar except instead of having multiple outputs (in a set or
map), they have a single one. This is for everything to the left of the
rightmost `^`.

`NixStringContextElem` has an analogous change, and now can reuse
`SingleDerivedPath` at the top level. In fact, if we ever get rid of
`DrvDeep`, `NixStringContextElem` could be replaced with
`SingleDerivedPath` entirely!

Important note: some JSON formats have changed.

We already can *produce* dynamic derivations, but we can't refer to them
directly. Today, we can merely express building or example at the top
imperatively over time by building `foo.drv^bar.drv`, and then with a
second nix invocation doing `<result-from-first>^baz`, but this is not
declarative. The ethos of Nix of being able to write down the full plan
everything you want to do, and then execute than plan with a single
command, and for that we need the new inductive form of these types.

Co-authored-by: Robert Hensing <roberth@users.noreply.github.com>
Co-authored-by: Valentin Gagarin <valentin.gagarin@tweag.io>
This commit is contained in:
John Ericson 2023-01-15 17:39:04 -05:00
parent d00fe5f225
commit 60b7121d2c
48 changed files with 1136 additions and 267 deletions
Download patch file Download diff file Expand all files Collapse all files

85
src/libstore/misc.cc
View file

@ -132,7 +132,7 @@ void Store::queryMissing(const std::vector<DerivedPath> & targets,
}
for (auto & i : drv.inputDrvs)
pool.enqueue(std::bind(doPath, DerivedPath::Built { i.first, i.second }));
pool.enqueue(std::bind(doPath, DerivedPath::Built { makeConstantStorePathRef(i.first), i.second }));
};
auto checkOutput = [&](
@ -176,10 +176,18 @@ void Store::queryMissing(const std::vector<DerivedPath> & targets,
std::visit(overloaded {
[&](const DerivedPath::Built & bfd) {
if (!isValidPath(bfd.drvPath)) {
auto drvPathP = std::get_if<DerivedPath::Opaque>(&*bfd.drvPath);
if (!drvPathP) {
// TODO make work in this case.
warn("Ignoring dynamic derivation %s while querying missing paths; not yet implemented", bfd.drvPath->to_string(*this));
return;
}
auto & drvPath = drvPathP->path;
if (!isValidPath(drvPath)) {
// FIXME: we could try to substitute the derivation.
auto state(state_.lock());
state->unknown.insert(bfd.drvPath);
state->unknown.insert(drvPath);
return;
}
@ -187,7 +195,7 @@ void Store::queryMissing(const std::vector<DerivedPath> & targets,
/* true for regular derivations, and CA derivations for which we
have a trust mapping for all wanted outputs. */
auto knownOutputPaths = true;
for (auto & [outputName, pathOpt] : queryPartialDerivationOutputMap(bfd.drvPath)) {
for (auto & [outputName, pathOpt] : queryPartialDerivationOutputMap(drvPath)) {
if (!pathOpt) {
knownOutputPaths = false;
break;
@ -197,15 +205,15 @@ void Store::queryMissing(const std::vector<DerivedPath> & targets,
}
if (knownOutputPaths && invalid.empty()) return;
auto drv = make_ref<Derivation>(derivationFromPath(bfd.drvPath));
ParsedDerivation parsedDrv(StorePath(bfd.drvPath), *drv);
auto drv = make_ref<Derivation>(derivationFromPath(drvPath));
ParsedDerivation parsedDrv(StorePath(drvPath), *drv);
if (knownOutputPaths && settings.useSubstitutes && parsedDrv.substitutesAllowed()) {
auto drvState = make_ref<Sync<DrvState>>(DrvState(invalid.size()));
for (auto & output : invalid)
pool.enqueue(std::bind(checkOutput, bfd.drvPath, drv, output, drvState));
pool.enqueue(std::bind(checkOutput, drvPath, drv, output, drvState));
} else
mustBuildDrv(bfd.drvPath, *drv);
mustBuildDrv(drvPath, *drv);
},
[&](const DerivedPath::Opaque & bo) {
@ -310,7 +318,9 @@ std::map<DrvOutput, StorePath> drvOutputReferences(
OutputPathMap resolveDerivedPath(Store & store, const DerivedPath::Built & bfd, Store * evalStore_)
{
auto outputsOpt_ = store.queryPartialDerivationOutputMap(bfd.drvPath, evalStore_);
auto drvPath = resolveDerivedPath(store, *bfd.drvPath, evalStore_);
auto outputsOpt_ = store.queryPartialDerivationOutputMap(drvPath, evalStore_);
auto outputsOpt = std::visit(overloaded {
[&](const OutputsSpec::All &) {
@ -325,7 +335,7 @@ OutputPathMap resolveDerivedPath(Store & store, const DerivedPath::Built & bfd,
if (!pOutputPathOpt)
throw Error(
"the derivation '%s' doesn't have an output named '%s'",
store.printStorePath(bfd.drvPath), output);
bfd.drvPath->to_string(store), output);
outputsOpt.insert_or_assign(output, std::move(*pOutputPathOpt));
}
return outputsOpt;
@ -335,11 +345,64 @@ OutputPathMap resolveDerivedPath(Store & store, const DerivedPath::Built & bfd,
OutputPathMap outputs;
for (auto & [outputName, outputPathOpt] : outputsOpt) {
if (!outputPathOpt)
throw MissingRealisation(store.printStorePath(bfd.drvPath), outputName);
throw MissingRealisation(bfd.drvPath->to_string(store), outputName);
auto & outputPath = *outputPathOpt;
outputs.insert_or_assign(outputName, outputPath);
}
return outputs;
}
StorePath resolveDerivedPath(Store & store, const SingleDerivedPath & req, Store * evalStore_)
{
auto & evalStore = evalStore_ ? *evalStore_ : store;
return std::visit(overloaded {
[&](const SingleDerivedPath::Opaque & bo) {
return bo.path;
},
[&](const SingleDerivedPath::Built & bfd) {
auto drvPath = resolveDerivedPath(store, *bfd.drvPath, evalStore_);
auto outputPaths = evalStore.queryPartialDerivationOutputMap(drvPath, evalStore_);
if (outputPaths.count(bfd.output) == 0)
throw Error("derivation '%s' does not have an output named '%s'",
store.printStorePath(drvPath), bfd.output);
auto & optPath = outputPaths.at(bfd.output);
if (!optPath)
throw Error("'%s' does not yet map to a known concrete store path",
bfd.to_string(store));
return *optPath;
},
}, req.raw());
}
OutputPathMap resolveDerivedPath(Store & store, const DerivedPath::Built & bfd)
{
auto drvPath = resolveDerivedPath(store, *bfd.drvPath);
auto outputMap = store.queryDerivationOutputMap(drvPath);
auto outputsLeft = std::visit(overloaded {
[&](const OutputsSpec::All &) {
return StringSet {};
},
[&](const OutputsSpec::Names & names) {
return static_cast<StringSet>(names);
},
}, bfd.outputs.raw());
for (auto iter = outputMap.begin(); iter != outputMap.end();) {
auto & outputName = iter->first;
if (bfd.outputs.contains(outputName)) {
outputsLeft.erase(outputName);
++iter;
} else {
iter = outputMap.erase(iter);
}
}
if (!outputsLeft.empty())
throw Error("derivation '%s' does not have an outputs %s",
store.printStorePath(drvPath),
concatStringsSep(", ", quoteStrings(std::get<OutputsSpec::Names>(bfd.outputs))));
return outputMap;
}
}