From 4ac4f675df3da01b6d814cd328dd3219dd472ac9 Mon Sep 17 00:00:00 2001 From: Eelco Dolstra Date: Tue, 5 Jun 2018 16:04:41 +0200 Subject: [PATCH] Don't require --fallback to recover from disappeared binary cache NARs --- src/libstore/binary-cache-store.cc | 6 +++++- src/libstore/build.cc | 32 ++++++++++++++++++++---------- src/libstore/store-api.hh | 1 + tests/binary-cache.sh | 19 +++++++++++++----- 4 files changed, 41 insertions(+), 17 deletions(-) diff --git a/src/libstore/binary-cache-store.cc b/src/libstore/binary-cache-store.cc index 11fa3cae2..76c0a1a89 100644 --- a/src/libstore/binary-cache-store.cc +++ b/src/libstore/binary-cache-store.cc @@ -218,7 +218,11 @@ void BinaryCacheStore::narFromPath(const Path & storePath, Sink & sink) auto info = queryPathInfo(storePath).cast(); auto source = sinkToSource([this, url{info->url}](Sink & sink) { - getFile(url, sink); + try { + getFile(url, sink); + } catch (NoSuchBinaryCacheFile & e) { + throw SubstituteGone(e.what()); + } }); stats.narRead++; diff --git a/src/libstore/build.cc b/src/libstore/build.cc index 07b533783..8eb192059 100644 --- a/src/libstore/build.cc +++ b/src/libstore/build.cc @@ -733,7 +733,7 @@ private: /* Whether to retry substituting the outputs after building the inputs. */ - bool retrySubstitution = false; + bool retrySubstitution; /* The derivation stored at drvPath. */ std::unique_ptr drv; @@ -1123,6 +1123,8 @@ void DerivationGoal::haveDerivation() { trace("have derivation"); + retrySubstitution = false; + for (auto & i : drv->outputs) worker.store.addTempRoot(i.second.path); @@ -1161,7 +1163,7 @@ void DerivationGoal::outputsSubstituted() /* If the substitutes form an incomplete closure, then we should build the dependencies of this derivation, but after that, we can still use the substitutes for this derivation itself. */ - if (nrIncompleteClosure > 0 && !retrySubstitution) retrySubstitution = true; + if (nrIncompleteClosure > 0) retrySubstitution = true; nrFailed = nrNoSubstituters = nrIncompleteClosure = 0; @@ -3524,8 +3526,8 @@ private: /* The current substituter. */ std::shared_ptr sub; - /* Whether any substituter can realise this path. */ - bool hasSubstitute; + /* Whether a substituter failed. */ + bool substituterFailed = false; /* Path info returned by the substituter's query info operation. */ std::shared_ptr info; @@ -3589,7 +3591,6 @@ public: SubstitutionGoal::SubstitutionGoal(const Path & storePath, Worker & worker, RepairFlag repair) : Goal(worker) - , hasSubstitute(false) , repair(repair) { this->storePath = storePath; @@ -3653,9 +3654,9 @@ void SubstitutionGoal::tryNext() /* Hack: don't indicate failure if there were no substituters. In that case the calling derivation should just do a build. */ - amDone(hasSubstitute ? ecFailed : ecNoSubstituters); + amDone(substituterFailed ? ecFailed : ecNoSubstituters); - if (hasSubstitute) { + if (substituterFailed) { worker.failedSubstitutions++; worker.updateProgress(); } @@ -3691,8 +3692,6 @@ void SubstitutionGoal::tryNext() worker.updateProgress(); - hasSubstitute = true; - /* Bail out early if this substituter lacks a valid signature. LocalStore::addToStore() also checks for this, but only after we've downloaded the path. */ @@ -3807,8 +3806,19 @@ void SubstitutionGoal::finished() state = &SubstitutionGoal::init; worker.waitForAWhile(shared_from_this()); return; - } catch (Error & e) { - printError(e.msg()); + } catch (std::exception & e) { + printError(e.what()); + + /* Cause the parent build to fail unless --fallback is given, + or the substitute has disappeared. The latter case behaves + the same as the substitute never having existed in the + first place. */ + try { + throw; + } catch (SubstituteGone &) { + } catch (...) { + substituterFailed = true; + } /* Try the next substitute. */ state = &SubstitutionGoal::tryNext; diff --git a/src/libstore/store-api.hh b/src/libstore/store-api.hh index 6ee2d5506..7c5b495a4 100644 --- a/src/libstore/store-api.hh +++ b/src/libstore/store-api.hh @@ -22,6 +22,7 @@ MakeError(SubstError, Error) MakeError(BuildError, Error) /* denotes a permanent build failure */ MakeError(InvalidPath, Error) MakeError(Unsupported, Error) +MakeError(SubstituteGone, Error) struct BasicDerivation; diff --git a/tests/binary-cache.sh b/tests/binary-cache.sh index cbcdca89b..eb58ae7c1 100644 --- a/tests/binary-cache.sh +++ b/tests/binary-cache.sh @@ -76,19 +76,28 @@ if nix-store --substituters "file://$cacheDir" -r $outPath; then fi -# Test whether fallback works if we have cached info but the -# corresponding NAR has disappeared. +# Test whether fallback works if a NAR has disappeared. This does not require --fallback. clearStore -nix-build --substituters "file://$cacheDir" dependencies.nix --dry-run # get info - -mkdir $cacheDir/tmp mv $cacheDir/nar $cacheDir/nar2 +nix-build --substituters "file://$cacheDir" --no-require-sigs dependencies.nix -o $TEST_ROOT/result + +mv $cacheDir/nar2 $cacheDir/nar + + +# Test whether fallback works if a NAR is corrupted. This does require --fallback. +clearStore + +mv $cacheDir/nar $cacheDir/nar2 +mkdir $cacheDir/nar +for i in $(cd $cacheDir/nar2 && echo *); do touch $cacheDir/nar/$i; done + (! nix-build --substituters "file://$cacheDir" --no-require-sigs dependencies.nix -o $TEST_ROOT/result) nix-build --substituters "file://$cacheDir" --no-require-sigs dependencies.nix -o $TEST_ROOT/result --fallback +rm -rf $cacheDir/nar mv $cacheDir/nar2 $cacheDir/nar