From 8eb73a87245acf9d93dc401831b629981864fa58 Mon Sep 17 00:00:00 2001 From: John Ericson Date: Sat, 22 Aug 2020 20:44:47 +0000 Subject: [PATCH] CA derivations that depend on other CA derivations MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Co-authored-by: Théophane Hufschmitt --- src/libstore/build.cc | 51 +++++++++++++++++++++++++++++++---- src/libstore/derivations.cc | 53 +++++++++++++++++++++++++++++++++++++ src/libstore/derivations.hh | 18 +++++++++++++ src/libstore/local-store.cc | 27 +++++++++++++++++-- tests/content-addressed.nix | 48 ++++++++++++++++++++++++--------- tests/content-addressed.sh | 20 +++++++------- 6 files changed, 189 insertions(+), 28 deletions(-) diff --git a/src/libstore/build.cc b/src/libstore/build.cc index 6baaa31d9..f5256bf87 100644 --- a/src/libstore/build.cc +++ b/src/libstore/build.cc @@ -984,6 +984,8 @@ private: void tryLocalBuild(); void buildDone(); + void resolvedFinished(); + /* Is the build hook willing to perform the build? */ HookReply tryBuildHook(); @@ -1451,8 +1453,39 @@ void DerivationGoal::inputsRealised() /* Determine the full set of input paths. */ /* First, the input derivations. */ - if (useDerivation) - for (auto & [depDrvPath, wantedDepOutputs] : dynamic_cast(drv.get())->inputDrvs) { + if (useDerivation) { + auto & fullDrv = *dynamic_cast(drv.get()); + + if (!fullDrv.inputDrvs.empty() && fullDrv.type() == DerivationType::CAFloating) { + /* We are be able to resolve this derivation based on the + now-known results of dependencies. If so, we become a stub goal + aliasing that resolved derivation goal */ + Derivation drvResolved { fullDrv.resolve(worker.store) }; + + auto pathResolved = writeDerivation(worker.store, drvResolved); + /* Add to memotable to speed up downstream goal's queries with the + original derivation. */ + drvPathResolutions.lock()->insert_or_assign(drvPath, pathResolved); + + auto msg = fmt("Resolved derivation: '%s' -> '%s'", + worker.store.printStorePath(drvPath), + worker.store.printStorePath(pathResolved)); + act = std::make_unique(*logger, lvlInfo, actBuildWaiting, msg, + Logger::Fields { + worker.store.printStorePath(drvPath), + worker.store.printStorePath(pathResolved), + }); + + auto resolvedGoal = worker.makeDerivationGoal( + pathResolved, wantedOutputs, + buildMode == bmRepair ? bmRepair : bmNormal); + addWaitee(resolvedGoal); + + state = &DerivationGoal::resolvedFinished; + return; + } + + for (auto & [depDrvPath, wantedDepOutputs] : fullDrv.inputDrvs) { /* Add the relevant output closures of the input derivation `i' as input paths. Only add the closures of output paths that are specified as inputs. */ @@ -1472,6 +1505,7 @@ void DerivationGoal::inputsRealised() worker.store.printStorePath(drvPath), j, worker.store.printStorePath(drvPath)); } } + } /* Second, the input sources. */ worker.store.computeFSClosure(drv->inputSrcs, inputPaths); @@ -1893,6 +1927,9 @@ void DerivationGoal::buildDone() done(BuildResult::Built); } +void DerivationGoal::resolvedFinished() { + done(BuildResult::Built); +} HookReply DerivationGoal::tryBuildHook() { @@ -2065,7 +2102,7 @@ void linkOrCopy(const Path & from, const Path & to) file (e.g. 32000 of ext3), which is quite possible after a 'nix-store --optimise'. FIXME: actually, why don't we just bind-mount in this case? - + It can also fail with EPERM in BeegFS v7 and earlier versions which don't allow hard-links to other directories */ if (errno != EMLINK && errno != EPERM) @@ -4248,10 +4285,14 @@ void DerivationGoal::registerOutputs() { ValidPathInfos infos2; for (auto & [outputName, newInfo] : infos) { - /* FIXME: we will want to track this mapping in the DB whether or - not we have a drv file. */ if (useDerivation) worker.store.linkDeriverToPath(drvPath, outputName, newInfo.path); + else { + /* Once a floating CA derivations reaches this point, it must + already be resolved, drvPath the basic derivation path, and + a file existsing at that path for sake of the DB's foreign key. */ + assert(drv->type() != DerivationType::CAFloating); + } infos2.push_back(newInfo); } worker.store.registerValidPaths(infos2); diff --git a/src/libstore/derivations.cc b/src/libstore/derivations.cc index 34541227b..d96d4083d 100644 --- a/src/libstore/derivations.cc +++ b/src/libstore/derivations.cc @@ -672,4 +672,57 @@ std::string downstreamPlaceholder(const Store & store, const StorePath & drvPath return "/" + hashString(htSHA256, clearText).to_string(Base32, false); } + +// N.B. Outputs are left unchanged +static void rewriteDerivation(Store & store, BasicDerivation & drv, const StringMap & rewrites) { + + debug("Rewriting the derivation"); + + for (auto &rewrite: rewrites) { + debug("rewriting %s as %s", rewrite.first, rewrite.second); + } + + drv.builder = rewriteStrings(drv.builder, rewrites); + for (auto & arg: drv.args) { + arg = rewriteStrings(arg, rewrites); + } + + StringPairs newEnv; + for (auto & envVar: drv.env) { + auto envName = rewriteStrings(envVar.first, rewrites); + auto envValue = rewriteStrings(envVar.second, rewrites); + newEnv.emplace(envName, envValue); + } + drv.env = newEnv; +} + + +Sync drvPathResolutions; + +BasicDerivation Derivation::resolve(Store & store) { + BasicDerivation resolved { *this }; + + // Input paths that we'll want to rewrite in the derivation + StringMap inputRewrites; + + for (auto & input : inputDrvs) { + auto inputDrvOutputs = store.queryPartialDerivationOutputMap(input.first); + StringSet newOutputNames; + for (auto & outputName : input.second) { + auto actualPathOpt = inputDrvOutputs.at(outputName); + if (!actualPathOpt) + throw Error("input drv '%s' wasn't yet built", store.printStorePath(input.first)); + auto actualPath = *actualPathOpt; + inputRewrites.emplace( + downstreamPlaceholder(store, input.first, outputName), + store.printStorePath(actualPath)); + resolved.inputSrcs.insert(std::move(actualPath)); + } + } + + rewriteDerivation(store, resolved, inputRewrites); + + return resolved; +} + } diff --git a/src/libstore/derivations.hh b/src/libstore/derivations.hh index 2ea4178c0..0bb565e8a 100644 --- a/src/libstore/derivations.hh +++ b/src/libstore/derivations.hh @@ -4,6 +4,7 @@ #include "types.hh" #include "hash.hh" #include "content-address.hh" +#include "sync.hh" #include #include @@ -127,6 +128,13 @@ struct Derivation : BasicDerivation std::string unparse(const Store & store, bool maskOutputs, std::map * actualInputs = nullptr) const; + /* Return the underlying basic derivation but with + + 1. input drv outputs moved to input sources. + + 2. placeholders replaced with realized input store paths. */ + BasicDerivation resolve(Store & store); + Derivation() = default; Derivation(BasicDerivation && bd) : BasicDerivation(std::move(bd)) { } }; @@ -187,6 +195,16 @@ typedef std::map DrvHashes; extern DrvHashes drvHashes; // FIXME: global, not thread-safe +/* Memoisation of `readDerivation(..).resove()`. */ +typedef std::map< + StorePath, + std::optional +> DrvPathResolutions; + +// FIXME: global, though at least thread-safe. +// FIXME: arguably overlaps with hashDerivationModulo memo table. +extern Sync drvPathResolutions; + bool wantOutput(const string & output, const std::set & wanted); struct Source; diff --git a/src/libstore/local-store.cc b/src/libstore/local-store.cc index 0086bb13e..e51d127b3 100644 --- a/src/libstore/local-store.cc +++ b/src/libstore/local-store.cc @@ -803,13 +803,36 @@ StorePathSet LocalStore::queryValidDerivers(const StorePath & path) } -std::map> LocalStore::queryPartialDerivationOutputMap(const StorePath & path) +std::map> LocalStore::queryPartialDerivationOutputMap(const StorePath & path_) { + auto path = path_; std::map> outputs; - BasicDerivation drv = readDerivation(path); + Derivation drv = readDerivation(path); for (auto & [outName, _] : drv.outputs) { outputs.insert_or_assign(outName, std::nullopt); } + bool haveCached = false; + { + auto resolutions = drvPathResolutions.lock(); + auto resolvedPathOptIter = resolutions->find(path); + if (resolvedPathOptIter != resolutions->end()) { + auto & [_, resolvedPathOpt] = *resolvedPathOptIter; + if (resolvedPathOpt) + path = *resolvedPathOpt; + haveCached = true; + } + } + /* can't just use else-if instead of `!haveCached` because we need to unlock + `drvPathResolutions` before it is locked in `Derivation::resolve`. */ + if (!haveCached && drv.type() == DerivationType::CAFloating) { + /* Resolve drv and use that path instead. */ + auto pathResolved = writeDerivation(*this, drv.resolve(*this)); + /* Store in memo table. */ + /* FIXME: memo logic should not be local-store specific, should have + wrapper-method instead. */ + drvPathResolutions.lock()->insert_or_assign(path, pathResolved); + path = std::move(pathResolved); + } return retrySQLite>>([&]() { auto state(_state.lock()); diff --git a/tests/content-addressed.nix b/tests/content-addressed.nix index 586e4cba6..a46c21164 100644 --- a/tests/content-addressed.nix +++ b/tests/content-addressed.nix @@ -4,16 +4,40 @@ with import ./config.nix; # A simple content-addressed derivation. # The derivation can be arbitrarily modified by passing a different `seed`, # but the output will always be the same -mkDerivation { - name = "simple-content-addressed"; - buildCommand = '' - set -x - echo "Building a CA derivation" - echo "The seed is ${toString seed}" - mkdir -p $out - echo "Hello World" > $out/hello - ''; - __contentAddressed = true; - outputHashMode = "recursive"; - outputHashAlgo = "sha256"; +rec { + root = mkDerivation { + name = "simple-content-addressed"; + buildCommand = '' + set -x + echo "Building a CA derivation" + echo "The seed is ${toString seed}" + mkdir -p $out + echo "Hello World" > $out/hello + ''; + __contentAddressed = true; + outputHashMode = "recursive"; + outputHashAlgo = "sha256"; + }; + dependent = mkDerivation { + name = "dependent"; + buildCommand = '' + echo "building a dependent derivation" + mkdir -p $out + echo ${root}/hello > $out/dep + ''; + __contentAddressed = true; + outputHashMode = "recursive"; + outputHashAlgo = "sha256"; + }; + transitivelyDependent = mkDerivation { + name = "transitively-dependent"; + buildCommand = '' + echo "building transitively-dependent" + cat ${dependent}/dep + echo ${dependent} > $out + ''; + __contentAddressed = true; + outputHashMode = "recursive"; + outputHashAlgo = "sha256"; + }; } diff --git a/tests/content-addressed.sh b/tests/content-addressed.sh index 2968f3a8c..522310585 100644 --- a/tests/content-addressed.sh +++ b/tests/content-addressed.sh @@ -2,15 +2,17 @@ source common.sh -clearStore -clearCache - -export REMOTE_STORE=file://$cacheDir - -drv=$(nix-instantiate --experimental-features ca-derivations ./content-addressed.nix --arg seed 1) +drv=$(nix-instantiate --experimental-features ca-derivations ./content-addressed.nix -A root --arg seed 1) nix --experimental-features 'nix-command ca-derivations' show-derivation --derivation "$drv" --arg seed 1 -out1=$(nix-build --experimental-features ca-derivations ./content-addressed.nix --arg seed 1 --no-out-link) -out2=$(nix-build --experimental-features ca-derivations ./content-addressed.nix --arg seed 2 --no-out-link) +testDerivation () { + local derivationPath=$1 + local commonArgs=("--experimental-features" "ca-derivations" "./content-addressed.nix" "-A" "$derivationPath" "--no-out-link") + local out1=$(nix-build "${commonArgs[@]}" --arg seed 1) + local out2=$(nix-build "${commonArgs[@]}" --arg seed 2) + test $out1 == $out2 +} -test $out1 == $out2 +testDerivation root +testDerivation dependent +testDerivation transitivelyDependent