| // Copyright 2014 The Bazel Authors. All rights reserved. |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| package com.google.devtools.build.lib.skyframe; |
| |
| import com.github.benmanes.caffeine.cache.Cache; |
| import com.github.benmanes.caffeine.cache.Caffeine; |
| import com.google.common.base.Preconditions; |
| import com.google.common.base.Predicates; |
| import com.google.common.collect.ImmutableList; |
| import com.google.common.collect.ImmutableMap; |
| import com.google.common.collect.Lists; |
| import com.google.common.collect.Maps; |
| import com.google.common.flogger.GoogleLogger; |
| import com.google.common.hash.HashFunction; |
| import com.google.devtools.build.lib.analysis.BlazeDirectories; |
| import com.google.devtools.build.lib.cmdline.Label; |
| import com.google.devtools.build.lib.cmdline.LabelConstants; |
| import com.google.devtools.build.lib.cmdline.LabelSyntaxException; |
| import com.google.devtools.build.lib.cmdline.PackageIdentifier; |
| import com.google.devtools.build.lib.cmdline.RepositoryMapping; |
| import com.google.devtools.build.lib.cmdline.RepositoryName; |
| import com.google.devtools.build.lib.concurrent.BlazeInterners; |
| import com.google.devtools.build.lib.events.Event; |
| import com.google.devtools.build.lib.events.EventHandler; |
| import com.google.devtools.build.lib.events.ExtendedEventHandler; |
| import com.google.devtools.build.lib.events.ExtendedEventHandler.Postable; |
| import com.google.devtools.build.lib.events.StoredEventHandler; |
| import com.google.devtools.build.lib.io.InconsistentFilesystemException; |
| import com.google.devtools.build.lib.packages.BazelModuleContext; |
| import com.google.devtools.build.lib.packages.BazelStarlarkEnvironment; |
| import com.google.devtools.build.lib.packages.BuildFileNotFoundException; |
| import com.google.devtools.build.lib.packages.PackageFactory; |
| import com.google.devtools.build.lib.packages.StarlarkExportable; |
| import com.google.devtools.build.lib.packages.WorkspaceFileValue; |
| import com.google.devtools.build.lib.packages.semantics.BuildLanguageOptions; |
| import com.google.devtools.build.lib.server.FailureDetails.FailureDetail; |
| import com.google.devtools.build.lib.server.FailureDetails.StarlarkLoading; |
| import com.google.devtools.build.lib.server.FailureDetails.StarlarkLoading.Code; |
| import com.google.devtools.build.lib.skyframe.StarlarkBuiltinsFunction.BuiltinsFailedException; |
| import com.google.devtools.build.lib.util.DetailedExitCode; |
| import com.google.devtools.build.lib.util.Fingerprint; |
| import com.google.devtools.build.lib.util.Pair; |
| import com.google.devtools.build.lib.vfs.PathFragment; |
| import com.google.devtools.build.lib.vfs.Root; |
| import com.google.devtools.build.skyframe.RecordingSkyFunctionEnvironment; |
| import com.google.devtools.build.skyframe.SkyFunction; |
| import com.google.devtools.build.skyframe.SkyFunctionException; |
| import com.google.devtools.build.skyframe.SkyFunctionException.Transience; |
| import com.google.devtools.build.skyframe.SkyKey; |
| import com.google.devtools.build.skyframe.SkyValue; |
| import com.google.devtools.build.skyframe.SkyframeIterableResult; |
| import java.util.HashMap; |
| import java.util.HashSet; |
| import java.util.LinkedHashSet; |
| import java.util.List; |
| import java.util.Map; |
| import java.util.function.Consumer; |
| import javax.annotation.Nullable; |
| import net.starlark.java.eval.EvalException; |
| import net.starlark.java.eval.Module; |
| import net.starlark.java.eval.Mutability; |
| import net.starlark.java.eval.Starlark; |
| import net.starlark.java.eval.StarlarkSemantics; |
| import net.starlark.java.eval.StarlarkThread; |
| import net.starlark.java.syntax.LoadStatement; |
| import net.starlark.java.syntax.Location; |
| import net.starlark.java.syntax.Program; |
| import net.starlark.java.syntax.StarlarkFile; |
| import net.starlark.java.syntax.Statement; |
| import net.starlark.java.syntax.StringLiteral; |
| |
| /** |
| * A Skyframe function to look up and load a single .bzl module. |
| * |
| * <p>Given a {@link Label} referencing a .bzl file, attempts to locate the file and load it. The |
| * Label must be absolute, and must not reference the special {@code external} package. If loading |
| * is successful, returns a {@link BzlLoadValue} that encapsulates the loaded {@link Module} and its |
| * transitive digest information. If loading is unsuccessful, throws a {@link |
| * BzlLoadFunctionException} that encapsulates the cause of the failure. |
| * |
| * <p>This Skyframe function supports a special bzl "inlining" mode in which all (indirectly) |
| * recursive calls to {@code BzlLoadFunction} are made in the same thread rather than through |
| * Skyframe. This inlining mode's entry point is {@link #computeInline}; see that method for more |
| * details. Note that it may only be called on an instance of this Skyfunction created by {@link |
| * #createForInlining}. Bzl inlining is not to be confused with the separate inlining of {@code |
| * BzlCompileFunction} |
| */ |
| public class BzlLoadFunction implements SkyFunction { |
| |
| // Used for: 1) obtaining a RuleClassProvider to create the BazelStarlarkContext for Starlark |
| // evaluation; 2) providing predeclared environments to other Skyfunctions |
| // (StarlarkBuiltinsFunction, BzlCompileFunction) when they are inlined and called via a static |
| // computeInline() entry point. |
| private final PackageFactory packageFactory; |
| |
| // Used for determining paths to builtins bzls that live in the workspace. |
| private final BlazeDirectories directories; |
| |
| // Handles retrieving BzlCompileValues, either by calling Skyframe or by inlining |
| // BzlCompileFunction; the latter is not to be confused with inlining of BzlLoadFunction. See |
| // comment in create() for rationale. |
| private final ValueGetter getter; |
| |
| // Handles inlining of BzlLoadFunction calls. |
| @Nullable private final CachedBzlLoadDataManager cachedBzlLoadDataManager; |
| |
| private static final GoogleLogger logger = GoogleLogger.forEnclosingClass(); |
| |
| private BzlLoadFunction( |
| PackageFactory packageFactory, |
| BlazeDirectories directories, |
| ValueGetter getter, |
| @Nullable CachedBzlLoadDataManager cachedBzlLoadDataManager) { |
| this.packageFactory = packageFactory; |
| this.directories = directories; |
| this.getter = getter; |
| this.cachedBzlLoadDataManager = cachedBzlLoadDataManager; |
| } |
| |
| public static BzlLoadFunction create( |
| PackageFactory packageFactory, |
| BlazeDirectories directories, |
| HashFunction hashFunction, |
| Cache<BzlCompileValue.Key, BzlCompileValue> bzlCompileCache) { |
| return new BzlLoadFunction( |
| packageFactory, |
| directories, |
| // When we are not inlining BzlLoadValue nodes, there is no need to have separate |
| // BzlCompileValue nodes for bzl files. Instead we inline BzlCompileFunction for a |
| // strict memory win, at a small code complexity cost. |
| // |
| // Detailed explanation: |
| // (1) The BzlCompileValue node for a bzl file is used only for the computation of |
| // that file's BzlLoadValue node. So there's no concern about duplicate work that would |
| // otherwise get deduped by Skyframe. |
| // (2) BzlCompileValue doesn't have an interesting equality relation, so we have no |
| // hope of getting any interesting change-pruning of BzlCompileValue nodes. If we |
| // had an interesting equality relation that was e.g. able to ignore benign |
| // whitespace, then there would be a hypothetical benefit to having separate |
| // BzlCompileValue nodes (e.g. on incremental builds we'd be able to not re-execute |
| // top-level code in bzl files if the file were reparsed to an equivalent tree). |
| // TODO(adonovan): this will change once it truly compiles the code (soon). |
| // (3) A BzlCompileValue node lets us avoid redoing work on a BzlLoadFunction Skyframe |
| // restart, but we can also achieve that result ourselves with a cache that persists between |
| // Skyframe restarts. |
| // |
| // Therefore, BzlCompileValue nodes are wasteful from two perspectives: |
| // (a) BzlCompileValue contains syntax trees, and that business object is really |
| // just a temporary thing for bzl execution. Retaining it forever is pure waste. |
| // (b) The memory overhead of the extra Skyframe node and edge per bzl file is pure |
| // waste. |
| new InliningAndCachingGetter(packageFactory, hashFunction, bzlCompileCache), |
| /*cachedBzlLoadDataManager=*/ null); |
| } |
| |
| public static BzlLoadFunction createForInlining( |
| PackageFactory packageFactory, BlazeDirectories directories, int bzlLoadValueCacheSize) { |
| return new BzlLoadFunction( |
| packageFactory, |
| directories, |
| // When we are inlining BzlLoadValue nodes, then we want to have explicit BzlCompileValue |
| // nodes, since now (1) in the comment above doesn't hold. This way we read and parse each |
| // needed bzl file at most once total globally, rather than once per need (in the worst-case |
| // of a BzlLoadValue inlining cache miss). This is important in the situation where a bzl |
| // file is loaded by a lot of other bzl files or BUILD files. |
| RegularSkyframeGetter.INSTANCE, |
| new CachedBzlLoadDataManager(bzlLoadValueCacheSize)); |
| } |
| |
| @Override |
| @Nullable |
| public SkyValue compute(SkyKey skyKey, Environment env) |
| throws SkyFunctionException, InterruptedException { |
| BzlLoadValue.Key key = (BzlLoadValue.Key) skyKey.argument(); |
| try { |
| return computeInternal(key, env, /*inliningState=*/ null); |
| } catch (BzlLoadFailedException e) { |
| throw new BzlLoadFunctionException(e); |
| } |
| } |
| |
| /** |
| * Entry point for computing "inline", without any direct or indirect Skyframe calls back into |
| * {@link BzlLoadFunction}. (Other Skyframe calls are permitted.) |
| * |
| * <p><b>USAGE NOTES:</b> |
| * |
| * <ul> |
| * <li>This method is intended to be called from {@link PackageFunction} and {@link |
| * StarlarkBuiltinsFunction} and probably shouldn't be used anywhere else. If you think you |
| * need inline Starlark computation, consult with the Core subteam and check out |
| * cl/305127325 for an example of correcting a misuse. |
| * <li>If this method is used with --keep_going and if Skyframe evaluation will never be |
| * interrupted, then this function ensures that the evaluation graph and any error reported |
| * are deterministic. |
| * </ul> |
| * |
| * <p>Under bzl inlining, there is some calling context that wants to obtain a set of {@link |
| * BzlLoadValue}s without Skyframe evaluation. For example, a calling context can be a BUILD file |
| * trying to resolve its top-level {@code load} statements. Although this work proceeds in a |
| * single thread, multiple calling contexts may evaluate .bzls in parallel. To avoid redundant |
| * work, they share a single (global to this Skyfunction instance) cache in lieu of the regular |
| * Skyframe cache. Unlike the regular Skyframe cache, this cache stores only successes. |
| * |
| * <p>If two calling contexts race to compute the same .bzl, each one will see a different copy of |
| * it, and only one will end up in the shared cache. This presents a hazard: Suppose A and B both |
| * need foo.bzl, and A needs it twice due to a diamond dependency. If A and B race to compute |
| * foo.bzl, but B's computation populates the cache, then when A comes back to resolve it the |
| * second time it will observe a different {@code BzlLoadValue}. This leads to incorrect Starlark |
| * evaluation since Starlark values may rely on Java object identity (see b/138598337). Even if we |
| * weren't concerned about racing, A may also reevaluate previously computed items due to cache |
| * evictions. |
| * |
| * <p>To solve this, we keep a second cache, {@link InliningState#successfulLoads}, that is local |
| * to the current calling context, and which never evicts entries. Like the global cache discussed |
| * above, this cache stores only successes. This cache is always checked in preference to the |
| * shared one; it may deviate from the shared one in some of its entries, but the calling context |
| * won't know the difference. (Since bzl inlining is only used for the loading phase, we don't |
| * need to worry about Starlark values from different packages interacting.) The cache is stored |
| * as part of the {@code inliningState} passed in by the caller; the caller can obtain this object |
| * using {@link InliningState#create}. |
| * |
| * <p>As an aside, note that we can't avoid having {@link InliningState#successfulLoads} by simply |
| * naively blocking evaluation of .bzls on retrievals from the shared cache. This is because two |
| * contexts could deadlock while trying to evaluate an illegal {@code load()} cycle from opposite |
| * ends. It would be possible to construct a waits-for graph and perform cycle detection, or to |
| * monitor slow threads and do detection lazily, but these do not address the cache eviction |
| * issue. Alternatively, we could make Starlark tolerant of reloading, but that would be |
| * tantamount to implementing full Starlark serialization. |
| * |
| * <p>Since our local {@link InliningState#successfulLoads} stores only successes, a separate |
| * concern is that we don't want to unsuccessfully visit the same .bzl more than once in the same |
| * context. (A visitation is unsuccessful if it fails due to an error or if it cannot complete |
| * because of a missing Skyframe dep.) To address this concern we maintain a separate {@link |
| * InliningState#unsuccessfulLoads} set, and use this set to return null instead of duplicating an |
| * unsuccessful visitation. |
| * |
| * @return the requested {@code BzlLoadValue}, or null if there was a missing Skyframe dep, an |
| * unspecified exception in a Skyframe dep request, or if this was a duplicate unsuccessful |
| * visitation |
| */ |
| // TODO(brandjon): Pick one of the nouns "load" and "bzl" and use that term consistently. |
| @Nullable |
| BzlLoadValue computeInline(BzlLoadValue.Key key, InliningState inliningState) |
| throws BzlLoadFailedException, InterruptedException { |
| Preconditions.checkNotNull(cachedBzlLoadDataManager); |
| CachedBzlLoadData cachedData = computeInlineCachedData(key, inliningState); |
| return cachedData != null ? cachedData.getValue() : null; |
| } |
| |
| /** |
| * Retrieves or creates the requested {@link CachedBzlLoadData} object for the given bzl, entering |
| * it into the local and shared caches. This is the entry point for recursive calls to the inline |
| * code path. |
| * |
| * @return null if there was a missing Skyframe dep, an unspecified exception in a Skyframe dep |
| * request, or if this was a duplicate unsuccessful visitation |
| */ |
| @Nullable |
| private CachedBzlLoadData computeInlineCachedData( |
| BzlLoadValue.Key key, InliningState inliningState) |
| throws BzlLoadFailedException, InterruptedException { |
| // Try the caches of successful loads. We must try the thread-local cache before the shared, for |
| // consistency purposes (see the javadoc of #computeInline). |
| CachedBzlLoadData cachedData = inliningState.successfulLoads.get(key); |
| if (cachedData == null) { |
| cachedData = cachedBzlLoadDataManager.cache.getIfPresent(key); |
| if (cachedData != null) { |
| // Found a cache hit from another thread's computation. Register the cache hit's recorded |
| // deps as if we had requested them directly in the unwrapped environment. We do this for |
| // the unwrapped environment, not the recording environment, because there's no need to |
| // embed one CachedBzlLoadData's metadata inside another; the dependency relationship will |
| // still be accurately reflected in the cache by the call to addTransitiveDeps() via |
| // childCachedDataHandler at the bottom of this function. |
| // |
| // Also incorporate into successfulLoads any transitive cache hits that it does not already |
| // contains. |
| cachedData.traverse( |
| inliningState.recordingEnv.getDelegate()::registerDependencies, |
| inliningState.successfulLoads); |
| } |
| } |
| |
| // See if we've already unsuccessfully visited the bzl. "Unsuccessfully" includes getting null |
| // for a missing Skyframe dep; the top-level caller will use a fresh InliningState when it does |
| // its Skyframe restart. |
| if (inliningState.unsuccessfulLoads.contains(key)) { |
| return null; |
| } |
| |
| // If we're here, the bzl must have never been visited before in this calling context. Compute |
| // it ourselves, updating the other data structures as appropriate. |
| if (cachedData == null) { |
| try { |
| cachedData = computeInlineForCacheMiss(key, inliningState); |
| } finally { |
| if (cachedData != null) { |
| inliningState.successfulLoads.put(key, cachedData); |
| cachedBzlLoadDataManager.cache.put(key, cachedData); |
| } else { |
| inliningState.unsuccessfulLoads.add(key); |
| // Either propagate an exception or fall through for null return. |
| } |
| } |
| } |
| |
| // On success (from cache hit or from scratch), notify the parent CachedBzlLoadData of its new |
| // child. |
| if (cachedData != null) { |
| inliningState.childCachedDataHandler.accept(cachedData); |
| } |
| |
| return cachedData; |
| } |
| |
| @Nullable |
| private CachedBzlLoadData computeInlineForCacheMiss( |
| BzlLoadValue.Key key, InliningState inliningState) |
| throws BzlLoadFailedException, InterruptedException { |
| // We use an instrumented Skyframe env to capture Skyframe deps in the CachedBzlLoadData (see |
| // InliningState#recordingEnv). This generally includes transitive Skyframe deps, but |
| // specifically excludes deps underneath recursively loaded .bzls. In this way, the |
| // CachedBzlLoadData objects form a DAG that mirrors the bzl load graph: Each node still reaches |
| // *all* the transitive skyframe deps needed for its computation, but the bzl-level granularity |
| // allows for sharing of cached results for portions of the bzl load graph. |
| // |
| // Here we are at the boundary between one CachedBzlLoadData and the next. createChildState() |
| // unwraps the old recording env and starts a new one for a new node. |
| |
| InliningState childState = inliningState.createChildState(cachedBzlLoadDataManager); |
| childState.beginLoad(key); // track for cyclic load() detection |
| BzlLoadValue value; |
| try { |
| value = computeInternal(key, childState.recordingEnv, childState); |
| } finally { |
| childState.finishLoad(key); |
| } |
| if (value == null) { |
| return null; |
| } |
| |
| return childState.buildCachedData(key, value); |
| } |
| |
| public void resetInliningCache() { |
| cachedBzlLoadDataManager.reset(); |
| } |
| |
| /** |
| * An opaque object that holds state for the bzl inlining computation initiated by {@link |
| * #computeInline}. |
| * |
| * <p>An original caller of {@code computeInline} (e.g., {@link PackageFunction}) should obtain |
| * one of these objects using {@link InliningState#create}. When the same caller makes several |
| * calls to {@code computeInline} (e.g., for multiple top-level loads in the same BUILD file), the |
| * same object must be passed to each call. |
| * |
| * <p>When a Skyfunction that is called by {@code BzlLoadFunction}'s inlining code path in turn |
| * calls back into {@code computeInline}, it should forward along the same {@code InliningState} |
| * that it received. In particular, {@link StarlarkBuiltinsFunction} forwards the inlining state |
| * to ensure that 1) the .bzls that get loaded from the {@code @_builtins} pseudo-repository are |
| * properly recorded as dependencies of all .bzl files that use builtins injection, and 2) the |
| * builtins .bzls are not reevaluated. |
| */ |
| // TODO(brandjon): Consider making this even more opaque and encapsulating more of the details of |
| // inlining. E.g., merge beginLoad/finishLoad with child state tracking, and encapsulate |
| // management of [un]successfulLoads. |
| static class InliningState { |
| |
| /** |
| * The Skyframe environment, instrumented to record dependencies inside CachedBzlLoadData |
| * objects. A new CachedBzlLoadData, and therefore a new recording environment, is started in |
| * each call to computeInlineForCacheMiss(). The initial InliningState's recording environment |
| * doesn't instrument anything since it represents the piece of the work that will not be saved |
| * in any CachedBzlLoadData. |
| */ |
| private final RecordingSkyFunctionEnvironment recordingEnv; |
| |
| /** |
| * The builder of the CachedBzlLoadData node that we are currently working on, if any. Null iff |
| * we're the initial InliningState, where recordingEnv doesn't instrument anything. |
| */ |
| private final CachedBzlLoadData.Builder cachedDataBuilder; |
| |
| /** |
| * The set of bzls we're currently in the process of loading but haven't fully visited yet. This |
| * is used for cycle detection since we don't have the benefit of Skyframe's internal cycle |
| * detection. The set must use insertion order for correct error reporting. |
| * |
| * <p>This is disjoint with {@link #successfulLoads} and {@link #unsuccessfulLoads}. |
| * |
| * <p>This is local to current calling context. See {@link #computeInline}. |
| */ |
| // Keyed on the SkyKey, not the label, since label could theoretically be ambiguous, even though |
| // in practice keys from BUILD / WORKSPACE / builtins don't call each other. (Not sure if |
| // WORKSPACE chunking can cause duplicate labels to appear, but we're robust regardless.) |
| private final LinkedHashSet<BzlLoadValue.Key> loadStack; |
| |
| /** |
| * Cache of bzls that have been fully visited and successfully loaded to a value. |
| * |
| * <p>This and {@link #unsuccessfulLoads} partition the set of fully visited bzls. |
| * |
| * <p>This is local to current calling context. See {@link #computeInline}. |
| */ |
| private final Map<BzlLoadValue.Key, CachedBzlLoadData> successfulLoads; |
| |
| /** |
| * Set of bzls that have been fully visited, but were not successfully loaded to a value. |
| * |
| * <p>This and {@link #successfulLoads} partition the set of fully visited bzls, and is disjoint |
| * with {@link #loadStack}. |
| * |
| * <p>This is local to current calling context. See {@link #computeInline}. |
| */ |
| private final HashSet<BzlLoadValue.Key> unsuccessfulLoads; |
| |
| /** Called when a transitive {@code CachedBzlLoadData} is produced. */ |
| private final Consumer<CachedBzlLoadData> childCachedDataHandler; |
| |
| private InliningState( |
| RecordingSkyFunctionEnvironment recordingEnv, |
| CachedBzlLoadData.Builder cachedDataBuilder, |
| LinkedHashSet<BzlLoadValue.Key> loadStack, |
| Map<BzlLoadValue.Key, CachedBzlLoadData> successfulLoads, |
| HashSet<BzlLoadValue.Key> unsuccessfulLoads, |
| Consumer<CachedBzlLoadData> childCachedDataHandler) { |
| this.recordingEnv = recordingEnv; |
| this.cachedDataBuilder = cachedDataBuilder; |
| this.loadStack = loadStack; |
| this.successfulLoads = successfulLoads; |
| this.unsuccessfulLoads = unsuccessfulLoads; |
| this.childCachedDataHandler = childCachedDataHandler; |
| } |
| |
| /** |
| * Creates an initial {@code InliningState} with no information about previously loaded files |
| * (except the shared cache stored in {@link BzlLoadFunction}). |
| */ |
| static InliningState create(Environment env) { |
| return new InliningState( |
| new RecordingSkyFunctionEnvironment(env, x -> {}, x -> {}, x -> {}), |
| /*cachedDataBuilder=*/ null, |
| /*loadStack=*/ new LinkedHashSet<>(), |
| /*successfulLoads=*/ new HashMap<>(), |
| /*unsuccessfulLoads=*/ new HashSet<>(), |
| // No parent value to mutate |
| /*childCachedDataHandler=*/ x -> {}); |
| } |
| |
| /** |
| * Creates another InliningState from this one, but with the recording Skyframe environment set |
| * up to log dependency metadata into a CachedBzlLoadData node that is a child of this |
| * InliningState's node. |
| */ |
| private InliningState createChildState(CachedBzlLoadDataManager cachedBzlLoadDataManager) { |
| CachedBzlLoadData.Builder newBuilder = cachedBzlLoadDataManager.cachedDataBuilder(); |
| RecordingSkyFunctionEnvironment newRecordingEnv = |
| new RecordingSkyFunctionEnvironment( |
| recordingEnv.getDelegate(), |
| newBuilder::addDep, |
| newBuilder::addDeps, |
| newBuilder::noteException); |
| return new InliningState( |
| newRecordingEnv, |
| newBuilder, |
| loadStack, |
| successfulLoads, |
| unsuccessfulLoads, |
| newBuilder::addTransitiveDeps); |
| } |
| |
| /** |
| * Finishes construction of the current CachedBzlLoadData node. This InliningState object should |
| * not be used after calling this method. |
| */ |
| private CachedBzlLoadData buildCachedData(BzlLoadValue.Key key, BzlLoadValue value) { |
| cachedDataBuilder.setValue(value); |
| cachedDataBuilder.setKey(key); |
| return cachedDataBuilder.build(); |
| } |
| |
| /** Records entry to a {@code load()}, throwing an exception if a cycle is detected. */ |
| private void beginLoad(BzlLoadValue.Key key) throws BzlLoadFailedException { |
| if (!loadStack.add(key)) { |
| ImmutableList<BzlLoadValue.Key> cycle = |
| CycleUtils.splitIntoPathAndChain(Predicates.equalTo(key), loadStack).second; |
| throw new BzlLoadFailedException("Starlark load cycle: " + cycle, Code.CYCLE); |
| } |
| } |
| |
| /** Records exit from a {@code load()}. */ |
| private void finishLoad(BzlLoadValue.Key key) throws BzlLoadFailedException { |
| Preconditions.checkState(loadStack.remove(key), key); |
| } |
| |
| /** Retrieves the Skyframe environment to use to do work under this InliningState. */ |
| Environment getEnvironment() { |
| return recordingEnv; |
| } |
| } |
| |
| /** |
| * Entry point for compute logic that's common to both (bzl) inlining and non-inlining code paths. |
| */ |
| // It is vital that we don't return any value if any call to env#getValue(s)OrThrow throws an |
| // exception. We are allowed to wrap the thrown exception and rethrow it for any calling functions |
| // to handle though. |
| @Nullable |
| private BzlLoadValue computeInternal( |
| BzlLoadValue.Key key, Environment env, @Nullable InliningState inliningState) |
| throws BzlLoadFailedException, InterruptedException { |
| Label label = key.getLabel(); |
| PathFragment filePath = label.toPathFragment(); |
| |
| StarlarkBuiltinsValue builtins = getBuiltins(key, env, inliningState); |
| if (builtins == null) { |
| return null; |
| } |
| |
| BzlCompileValue.Key compileKey = |
| validatePackageAndGetCompileKey( |
| key, |
| env, |
| builtins.starlarkSemantics.get(BuildLanguageOptions.EXPERIMENTAL_BUILTINS_BZL_PATH)); |
| if (compileKey == null) { |
| return null; |
| } |
| BzlCompileValue compileValue; |
| try { |
| compileValue = getter.getBzlCompileValue(compileKey, env); |
| } catch (BzlCompileFunction.FailedIOException e) { |
| throw BzlLoadFailedException.errorReadingBzl(filePath, e); |
| } |
| if (compileValue == null) { |
| return null; |
| } |
| |
| BzlLoadValue result = null; |
| // Release the compiled bzl iff the value gets completely evaluated (to either error or non-null |
| // result). |
| boolean completed = true; |
| try { |
| result = computeInternalWithCompiledBzl(key, compileValue, builtins, env, inliningState); |
| completed = result != null; |
| } finally { |
| if (completed) { // only false on unexceptional null result |
| getter.doneWithBzlCompileValue(compileKey); |
| } |
| } |
| return result; |
| } |
| |
| /** |
| * Obtain a suitable StarlarkBuiltinsValue. |
| * |
| * <p>For BUILD-loaded .bzl files, this is a real builtins value, obtained using either Skyframe |
| * or inlining of StarlarkBuiltinsFunction (depending on whether {@code inliningState} is |
| * non-null). The returned value includes the StarlarkSemantics. |
| * |
| * <p>For other .bzl files, the builtins computation is not needed and would create a Skyframe |
| * cycle if requested, so we instead return an empty builtins value that just wraps the |
| * StarlarkSemantics. (NB: In the case of WORKSPACE-loaded .bzl files, the cycle goes through the |
| * repository remapping value. It's possible this could be avoided if we ever wanted to make this |
| * kind of .bzl file use builtins injection.) |
| */ |
| @Nullable |
| private StarlarkBuiltinsValue getBuiltins( |
| BzlLoadValue.Key key, Environment env, @Nullable InliningState inliningState) |
| throws BzlLoadFailedException, InterruptedException { |
| if (!(key instanceof BzlLoadValue.KeyForBuild)) { |
| StarlarkSemantics starlarkSemantics = PrecomputedValue.STARLARK_SEMANTICS.get(env); |
| if (starlarkSemantics == null) { |
| return null; |
| } |
| return StarlarkBuiltinsValue.createEmpty(starlarkSemantics); |
| } |
| try { |
| if (inliningState == null) { |
| return (StarlarkBuiltinsValue) |
| env.getValueOrThrow(StarlarkBuiltinsValue.key(), BuiltinsFailedException.class); |
| } else { |
| return StarlarkBuiltinsFunction.computeInline( |
| StarlarkBuiltinsValue.key(), inliningState, packageFactory, /*bzlLoadFunction=*/ this); |
| } |
| } catch (BuiltinsFailedException e) { |
| throw BzlLoadFailedException.builtinsFailed(key.getLabel(), e); |
| } |
| } |
| |
| /** |
| * Given a bzl key, validates that the corresponding package exists (if required) and returns the |
| * associated compile key based on the package's root. Returns null for a missing Skyframe dep or |
| * unspecified exception. |
| * |
| * <p>.bzl files are not necessarily targets, because they can be loaded by BUILD and other .bzl |
| * files without ever being declared in a BUILD file. However, .bzl files are still identified by |
| * a label in the same way that file targets are. In particular, it is illegal to refer to a .bzl |
| * file using a label whose package part is not the .bzl file's innermost containing package. For |
| * example, if pkg and pkg/subpkg have BUILD files but not pkg/subdir, then {@code |
| * pkg/subdir:foo.bzl} and {@code pkg:subpkg/foo.bzl} are disallowed. |
| * |
| * <p>In the case of builtins .bzl files, all labels are written as if the pseudo-repo constitutes |
| * one big package, e.g {@code @builtins//:some/path/foo.bzl}, but no BUILD file need exist. The |
| * compile key's root is determined by {@code --experimental_builtins_bzl_path} (passed as {@code |
| * builtinsBzlPath}) instead of by package lookup. |
| */ |
| @Nullable |
| private BzlCompileValue.Key validatePackageAndGetCompileKey( |
| BzlLoadValue.Key key, Environment env, String builtinsBzlPath) |
| throws BzlLoadFailedException, InterruptedException { |
| Label label = key.getLabel(); |
| |
| // Bypass package lookup entirely if builtins. |
| if (key.isBuiltins()) { |
| if (!label.getPackageName().isEmpty()) { |
| throw BzlLoadFailedException.noBuildFile(label, "@_builtins cannot have subpackages"); |
| } |
| return key.getCompileKey(getBuiltinsRoot(builtinsBzlPath)); |
| } |
| |
| // Do package lookup. |
| PathFragment dir = Label.getContainingDirectory(label); |
| PackageIdentifier dirId = PackageIdentifier.create(label.getRepository(), dir); |
| ContainingPackageLookupValue packageLookup; |
| try { |
| packageLookup = |
| (ContainingPackageLookupValue) |
| env.getValueOrThrow( |
| ContainingPackageLookupValue.key(dirId), |
| BuildFileNotFoundException.class, |
| InconsistentFilesystemException.class); |
| } catch (BuildFileNotFoundException | InconsistentFilesystemException e) { |
| throw BzlLoadFailedException.errorFindingContainingPackage(label.toPathFragment(), e); |
| } |
| if (packageLookup == null) { |
| return null; |
| } |
| |
| // Resolve to compile key or error. |
| BzlCompileValue.Key compileKey; |
| boolean packageOk = |
| packageLookup.hasContainingPackage() |
| && packageLookup.getContainingPackageName().equals(label.getPackageIdentifier()); |
| if (key.isBuildPrelude() && !packageOk) { |
| // Ignore the prelude, its package doesn't exist. |
| compileKey = BzlCompileValue.EMPTY_PRELUDE_KEY; |
| } else { |
| if (packageOk) { |
| compileKey = key.getCompileKey(packageLookup.getContainingPackageRoot()); |
| } else { |
| if (!packageLookup.hasContainingPackage()) { |
| throw BzlLoadFailedException.noBuildFile( |
| label, packageLookup.getReasonForNoContainingPackage()); |
| } else { |
| throw BzlLoadFailedException.labelCrossesPackageBoundary(label, packageLookup); |
| } |
| } |
| } |
| return compileKey; |
| } |
| |
| private Root getBuiltinsRoot(String builtinsBzlPath) { |
| // TODO(#11437): Remove once injection can't be disabled. |
| if (builtinsBzlPath.isEmpty()) { |
| throw new IllegalStateException("Requested builtins root, but injection is disabled"); |
| } |
| |
| // TODO(#11437): For the non-bundled case, should we consider interning the Root rather than |
| // constructing a new one each time? |
| Root root; |
| if (builtinsBzlPath.equals("%bundled%")) { |
| // May be null in tests, but in that case the builtins path shouldn't be set to %bundled%. |
| root = |
| Preconditions.checkNotNull( |
| packageFactory.getRuleClassProvider().getBundledBuiltinsRoot(), |
| "rule class provider does not specify a builtins root; either call" |
| + " setBuiltinsBzlZipResource() or else set --experimental_builtins_bzl_path to" |
| + " a root"); |
| } else if (builtinsBzlPath.equals("%workspace%")) { |
| String packagePath = |
| Preconditions.checkNotNull( |
| packageFactory.getRuleClassProvider().getBuiltinsBzlPackagePathInSource(), |
| "rule class provider does not specify a canonical package path to a builtins root;" |
| + " either call setBuiltinsBzlPackagePathInSource() or else do not set" |
| + "--experimental_builtins_bzl_path to %workspace%"); |
| // TODO(brandjon): Here we return a root that is underneath a package root. Since the root is |
| // itself not a package root, we don't get the benefit of any special DiffAwareness handling. |
| // This case probably isn't important since it doesn't occur in production Bazel, but |
| // presumably we might be able to add a special DiffAwareness for it if we wanted. |
| root = Root.fromPath(directories.getWorkspace().getRelative(packagePath)); |
| } else { |
| root = Root.fromPath(directories.getWorkspace().getRelative(builtinsBzlPath)); |
| } |
| return root; |
| } |
| |
| /** |
| * Compute logic for once the compiled .bzl has been fetched and confirmed to exist (though it may |
| * have Starlark errors). |
| */ |
| @Nullable |
| private BzlLoadValue computeInternalWithCompiledBzl( |
| BzlLoadValue.Key key, |
| BzlCompileValue compileValue, |
| StarlarkBuiltinsValue builtins, |
| Environment env, |
| @Nullable InliningState inliningState) |
| throws BzlLoadFailedException, InterruptedException { |
| // Ensure the .bzl exists and passes static checks (parsing, resolving). |
| // (A missing prelude file still returns a valid but empty BzlCompileValue.) |
| if (!compileValue.lookupSuccessful()) { |
| throw new BzlLoadFailedException(compileValue.getError(), Code.COMPILE_ERROR); |
| } |
| Program prog = compileValue.getProgram(); |
| |
| // Determine dependency BzlLoadValue keys for the load statements in this bzl. |
| // Labels are resolved relative to the current repo mapping. |
| RepositoryMapping repoMapping = getRepositoryMapping(key, env); |
| if (repoMapping == null) { |
| return null; |
| } |
| ImmutableList<Pair<String, Location>> programLoads = getLoadsFromProgram(prog); |
| ImmutableList<Label> loadLabels = |
| getLoadLabels( |
| env.getListener(), programLoads, key.getLabel().getPackageIdentifier(), repoMapping); |
| if (loadLabels == null) { |
| throw new BzlLoadFailedException( |
| String.format( |
| "module '%s'%s has invalid load statements", |
| key.getLabel().toPathFragment(), |
| StarlarkBuiltinsValue.isBuiltinsRepo(key.getLabel().getRepository()) |
| ? " (internal)" |
| : ""), |
| Code.PARSE_ERROR); |
| } |
| ImmutableList.Builder<BzlLoadValue.Key> loadKeys = |
| ImmutableList.builderWithExpectedSize(loadLabels.size()); |
| for (Label loadLabel : loadLabels) { |
| loadKeys.add(key.getKeyForLoad(loadLabel)); |
| } |
| |
| // Load .bzl modules. |
| // When not using bzl inlining, this is done in parallel for all loads. |
| List<BzlLoadValue> loadValues = |
| inliningState == null |
| ? computeBzlLoadsWithSkyframe(env, loadKeys.build(), programLoads) |
| : computeBzlLoadsWithInlining(env, loadKeys.build(), programLoads, inliningState); |
| if (loadValues == null) { |
| return null; // Skyframe deps unavailable |
| } |
| |
| // Accumulate a transitive digest of the bzl file, the digests of its direct loads, and the |
| // digest of the @_builtins pseudo-repository (if applicable). |
| Fingerprint fp = new Fingerprint(); |
| fp.addBytes(compileValue.getDigest()); |
| |
| // Populate the load map and add transitive digests to the fingerprint. |
| Map<String, Module> loadMap = Maps.newLinkedHashMapWithExpectedSize(programLoads.size()); |
| int i = 0; |
| for (Pair<String, Location> load : programLoads) { |
| BzlLoadValue v = loadValues.get(i++); |
| loadMap.put(load.first, v.getModule()); // dups ok |
| fp.addBytes(v.getTransitiveDigest()); |
| } |
| |
| // Retrieve predeclared symbols and complete the digest computation. |
| ImmutableMap<String, Object> predeclared = |
| getAndDigestPredeclaredEnvironment(key, builtins, fp); |
| if (predeclared == null) { |
| return null; |
| } |
| byte[] transitiveDigest = fp.digestAndReset(); |
| |
| // Construct the initial Starlark module, then execute the code and return the result. |
| // The additional information in BazelModuleContext reifies the load DAG. |
| // The module must match the environment used to compile the .bzl file. |
| Module module = Module.withPredeclared(builtins.starlarkSemantics, predeclared); |
| module.setClientData( |
| BazelModuleContext.create( |
| key.getLabel(), |
| repoMapping, |
| prog.getFilename(), |
| ImmutableMap.copyOf(loadMap), |
| transitiveDigest)); |
| |
| // executeBzlFile may post events to the Environment's handler, but events do not matter when |
| // caching BzlLoadValues. Note that executing the code mutates the module. |
| executeBzlFile( |
| prog, key.getLabel(), module, loadMap, builtins.starlarkSemantics, env.getListener()); |
| return new BzlLoadValue(module, transitiveDigest); |
| } |
| |
| private static RepositoryMapping getRepositoryMapping(BzlLoadValue.Key key, Environment env) |
| throws InterruptedException { |
| if (key.isBuiltins()) { |
| // Builtins .bzls never have a repo mapping defined for them, so return without requesting a |
| // RepositoryMappingValue. (NB: In addition to being a slight optimization, this avoids |
| // adding a reverse dependency on the special //external package, which helps avoid tickling |
| // some peculiarities of the Google-internal Skyframe implementation; see b/182293526 for |
| // details.) |
| return RepositoryMapping.ALWAYS_FALLBACK; |
| } |
| |
| Label enclosingFileLabel = key.getLabel(); |
| RepositoryName repoName = enclosingFileLabel.getRepository(); |
| |
| if (key instanceof BzlLoadValue.KeyForWorkspace) { |
| // Still during workspace file evaluation |
| BzlLoadValue.KeyForWorkspace keyForWorkspace = (BzlLoadValue.KeyForWorkspace) key; |
| if (keyForWorkspace.getWorkspaceChunk() == 0) { |
| // There is no previous workspace chunk |
| return RepositoryMapping.ALWAYS_FALLBACK; |
| } else { |
| SkyKey workspaceFileKey = |
| WorkspaceFileValue.key( |
| keyForWorkspace.getWorkspacePath(), keyForWorkspace.getWorkspaceChunk() - 1); |
| WorkspaceFileValue workspaceFileValue = (WorkspaceFileValue) env.getValue(workspaceFileKey); |
| // Note: we know for sure that the requested WorkspaceFileValue is fully computed so we do |
| // not need to check if it is null |
| return RepositoryMapping.createAllowingFallback( |
| workspaceFileValue.getRepositoryMapping().getOrDefault(repoName, ImmutableMap.of())); |
| // NOTE(wyv): this means that, in the WORKSPACE file, we can't load from a repo generated by |
| // bzlmod. If that's a problem, we should "fall back" to the bzlmod case below. |
| } |
| } |
| |
| if (key instanceof BzlLoadValue.KeyForBzlmod) { |
| if (repoName.equals(RepositoryName.BAZEL_TOOLS)) { |
| // Special case: we're only here to get the @bazel_tools repo (for example, for |
| // http_archive). This repo shouldn't have visibility into anything else (during repo |
| // generation), so we just return an empty repo mapping. |
| // TODO(wyv): disallow fallback. |
| return RepositoryMapping.ALWAYS_FALLBACK; |
| } |
| if (repoName.isMain()) { |
| // Special case: when we try to run an extension in the main repo, we need to grab the repo |
| // mapping for the main repo, which normally would include all WORKSPACE repos. This is |
| // problematic if the reason we're running an extension at all is that we're trying to do a |
| // `load` in WORKSPACE. So we specifically say that, to run an extension in the main repo, |
| // we ask for a repo mapping *without* WORKSPACE repos. |
| RepositoryMappingValue repositoryMappingValue = |
| (RepositoryMappingValue) |
| env.getValue(RepositoryMappingValue.KEY_FOR_ROOT_MODULE_WITHOUT_WORKSPACE_REPOS); |
| if (repositoryMappingValue == null) { |
| return null; |
| } |
| return repositoryMappingValue.getRepositoryMapping(); |
| } |
| } |
| |
| // This is either a .bzl loaded from BUILD files, or a .bzl loaded for bzlmod (in which case the |
| // .bzl file *has* to be from a Bazel module anyway). So we can just use the full repo mapping |
| // from RepositoryMappingFunction. |
| RepositoryMappingValue repositoryMappingValue = |
| (RepositoryMappingValue) env.getValue(RepositoryMappingValue.key(repoName)); |
| if (repositoryMappingValue == null) { |
| return null; |
| } |
| return repositoryMappingValue.getRepositoryMapping(); |
| } |
| |
| public static void checkValidLoadLabel(Label label, boolean fromBuiltinsRepo) |
| throws LabelSyntaxException { |
| if (!label.getName().endsWith(".bzl")) { |
| throw new LabelSyntaxException("The label must reference a file with extension '.bzl'"); |
| } |
| if (label.getPackageIdentifier().equals(LabelConstants.EXTERNAL_PACKAGE_IDENTIFIER)) { |
| throw new LabelSyntaxException( |
| "Starlark files may not be loaded from the //external package"); |
| } |
| if (fromBuiltinsRepo && !StarlarkBuiltinsValue.isBuiltinsRepo(label.getRepository())) { |
| throw new LabelSyntaxException( |
| ".bzl files in @_builtins cannot load from outside of @_builtins"); |
| } |
| } |
| |
| /** |
| * Given a list of {@code load("module")} strings and their locations, in source order, returns a |
| * corresponding list of Labels they each resolve to. Labels are resolved relative to {@code |
| * base}, the file's package. If any label is malformed, the function reports one or more errors |
| * to the handler and returns null. |
| */ |
| @Nullable |
| static ImmutableList<Label> getLoadLabels( |
| EventHandler handler, |
| ImmutableList<Pair<String, Location>> loads, |
| PackageIdentifier base, |
| RepositoryMapping repoMapping) { |
| // It's redundant that getRelativeWithRemapping needs a Label; |
| // a PackageIdentifier should suffice. Make one here. |
| Label buildLabel = getBUILDLabel(base); |
| |
| boolean ok = true; |
| |
| ImmutableList.Builder<Label> loadLabels = ImmutableList.builderWithExpectedSize(loads.size()); |
| for (Pair<String, Location> load : loads) { |
| // Parse the load statement's module string as a label. |
| // It must end in .bzl and not be in package "//external". |
| try { |
| Label label = buildLabel.getRelativeWithRemapping(load.first, repoMapping); |
| checkValidLoadLabel( |
| label, |
| /* fromBuiltinsRepo= */ StarlarkBuiltinsValue.isBuiltinsRepo(base.getRepository())); |
| loadLabels.add(label); |
| } catch (LabelSyntaxException ex) { |
| handler.handle(Event.error(load.second, "in load statement: " + ex.getMessage())); |
| ok = false; |
| } |
| } |
| return ok ? loadLabels.build() : null; |
| } |
| |
| /** Extracts load statements from compiled program (see {@link #getLoadLabels}). */ |
| static ImmutableList<Pair<String, Location>> getLoadsFromProgram(Program prog) { |
| int n = prog.getLoads().size(); |
| ImmutableList.Builder<Pair<String, Location>> loads = ImmutableList.builderWithExpectedSize(n); |
| for (int i = 0; i < n; i++) { |
| loads.add(Pair.of(prog.getLoads().get(i), prog.getLoadLocation(i))); |
| } |
| return loads.build(); |
| } |
| |
| /** Extracts load statements from file syntax (see {@link #getLoadLabels}). */ |
| static ImmutableList<Pair<String, Location>> getLoadsFromStarlarkFiles(List<StarlarkFile> files) { |
| ImmutableList.Builder<Pair<String, Location>> loads = ImmutableList.builder(); |
| for (StarlarkFile file : files) { |
| for (Statement stmt : file.getStatements()) { |
| if (stmt instanceof LoadStatement) { |
| StringLiteral module = ((LoadStatement) stmt).getImport(); |
| loads.add(Pair.of(module.getValue(), module.getStartLocation())); |
| } |
| } |
| } |
| return loads.build(); |
| } |
| |
| private static Label getBUILDLabel(PackageIdentifier pkgid) { |
| try { |
| return Label.create(pkgid, "BUILD"); |
| } catch (LabelSyntaxException e) { |
| // Shouldn't happen; the Label is well-formed by construction. |
| throw new IllegalStateException(e); |
| } |
| } |
| |
| /** |
| * Computes the BzlLoadValue for all given .bzl load keys using ordinary Skyframe evaluation, |
| * returning {@code null} if Skyframe deps were missing and have been requested. {@code |
| * programLoads} provides the locations of the load statements in source order, for error |
| * reporting. |
| */ |
| @Nullable |
| private static List<BzlLoadValue> computeBzlLoadsWithSkyframe( |
| Environment env, List<BzlLoadValue.Key> keys, List<Pair<String, Location>> programLoads) |
| throws BzlLoadFailedException, InterruptedException { |
| List<BzlLoadValue> bzlLoads = Lists.newArrayListWithExpectedSize(keys.size()); |
| SkyframeIterableResult values = env.getOrderedValuesAndExceptions(keys); |
| // Process loads (and report first error) in source order. |
| for (int i = 0; i < keys.size(); i++) { |
| try { |
| bzlLoads.add((BzlLoadValue) values.nextOrThrow(BzlLoadFailedException.class)); |
| } catch (BzlLoadFailedException ex) { |
| throw BzlLoadFailedException.whileLoadingDep(programLoads.get(i).second, ex); |
| } |
| } |
| return env.valuesMissing() ? null : bzlLoads; |
| } |
| |
| /** |
| * Computes the BzlLoadValue for all given keys by reusing this instance of the BzlLoadFunction, |
| * bypassing traditional Skyframe evaluation. {@code programLoads} provides the locations of the |
| * load statements in source order, for error reporting. |
| * |
| * @return null if there was a missing Skyframe dep, an unspecified exception in a Skyframe dep |
| * request, or if this was a duplicate unsuccessful visitation |
| */ |
| @Nullable |
| private List<BzlLoadValue> computeBzlLoadsWithInlining( |
| Environment env, |
| List<BzlLoadValue.Key> keys, |
| List<Pair<String, Location>> programLoads, |
| InliningState inliningState) |
| throws BzlLoadFailedException, InterruptedException { |
| Preconditions.checkState(env == inliningState.recordingEnv); |
| |
| List<BzlLoadValue> bzlLoads = Lists.newArrayListWithExpectedSize(keys.size()); |
| // For the sake of ensuring the graph structure is deterministic, we need to request all of our |
| // deps, even if some of them yield errors. The first exception that is seen gets deferred, to |
| // be raised after the loop. All other exceptions are swallowed. |
| // |
| // To see how immediately returning the first error leads to non-determinism, consider the case |
| // of two dependencies A and B, where A is in error and appears in a load statement above B. |
| // If A has completed at the time we request it, and if we were to immediately propagate that |
| // error, we never request B. On the other hand, if A is missing (null return), we do request B |
| // in the meantime for the sake of parallelism. |
| // |
| // This approach assumes --keep_going; determinism is not guaranteed otherwise. It also assumes |
| // InterruptedException does not occur, since we don't catch and defer it. |
| BzlLoadFailedException deferredException = null; |
| boolean valuesMissing = false; |
| for (int i = 0; i < keys.size(); i++) { |
| CachedBzlLoadData cachedData; |
| try { |
| cachedData = computeInlineCachedData(keys.get(i), inliningState); |
| } catch (BzlLoadFailedException e) { |
| if (deferredException == null) { |
| deferredException = BzlLoadFailedException.whileLoadingDep(programLoads.get(i).second, e); |
| } |
| continue; |
| } |
| if (cachedData == null) { |
| // A null value for `cachedData` can occur when it (or its transitive loads) has a Skyframe |
| // dep that is missing or in error. It can also occur if there's a transitive load on a bzl |
| // that was already seen by inliningState and which returned null (note: in this case, it's |
| // not necessarily true that there are missing Skyframe deps because this bzl could have |
| // already been visited unsuccessfully). In both these cases, we want to continue making our |
| // inline calls, so as to maximize the number of dependent (non-inlined) SkyFunctions that |
| // are requested and avoid a quadratic number of restarts. |
| valuesMissing = true; |
| } else { |
| bzlLoads.add(cachedData.getValue()); |
| } |
| } |
| if (deferredException != null) { |
| throw deferredException; |
| } |
| return valuesMissing ? null : bzlLoads; |
| } |
| |
| /** |
| * Obtains the predeclared environment for a .bzl file, based on the type of .bzl and (if |
| * applicable) the injected builtins. |
| * |
| * <p>Returns null if there was a missing Skyframe dep or unspecified exception. |
| * |
| * <p>In the case that injected builtins are used, updates the given fingerprint with the digest |
| * of the {@code @_builtins} pseudo-repository. |
| */ |
| @Nullable |
| private ImmutableMap<String, Object> getAndDigestPredeclaredEnvironment( |
| BzlLoadValue.Key key, StarlarkBuiltinsValue builtins, Fingerprint fp) |
| throws BzlLoadFailedException, InterruptedException { |
| BazelStarlarkEnvironment starlarkEnv = packageFactory.getBazelStarlarkEnvironment(); |
| if (key instanceof BzlLoadValue.KeyForBuild) { |
| // TODO(#11437): Remove ability to disable injection by setting flag to empty string. |
| if (builtins |
| .starlarkSemantics |
| .get(BuildLanguageOptions.EXPERIMENTAL_BUILTINS_BZL_PATH) |
| .isEmpty()) { |
| return starlarkEnv.getUninjectedBuildBzlEnv(); |
| } |
| fp.addBytes(builtins.transitiveDigest); |
| return builtins.predeclaredForBuildBzl; |
| } else if (key instanceof BzlLoadValue.KeyForWorkspace) { |
| return starlarkEnv.getWorkspaceBzlEnv(); |
| } else if (key instanceof BzlLoadValue.KeyForBzlmod) { |
| return starlarkEnv.getBzlmodBzlEnv(); |
| } else if (key instanceof BzlLoadValue.KeyForBuiltins) { |
| return starlarkEnv.getBuiltinsBzlEnv(); |
| } else { |
| throw new AssertionError("Unknown key type: " + key.getClass()); |
| } |
| } |
| |
| /** Executes the compiled .bzl file defining the module to be loaded. */ |
| private void executeBzlFile( |
| Program prog, |
| Label label, |
| Module module, |
| Map<String, Module> loadedModules, |
| StarlarkSemantics starlarkSemantics, |
| ExtendedEventHandler skyframeEventHandler) |
| throws BzlLoadFailedException, InterruptedException { |
| try (Mutability mu = Mutability.create("loading", label)) { |
| StarlarkThread thread = new StarlarkThread(mu, starlarkSemantics); |
| thread.setLoader(loadedModules::get); |
| StoredEventHandler starlarkEventHandler = new StoredEventHandler(); |
| thread.setPrintHandler(Event.makeDebugPrintHandler(starlarkEventHandler)); |
| packageFactory.getRuleClassProvider().setStarlarkThreadContext(thread, label); |
| execAndExport(prog, label, starlarkEventHandler, module, thread); |
| |
| Event.replayEventsOn(skyframeEventHandler, starlarkEventHandler.getEvents()); |
| for (Postable post : starlarkEventHandler.getPosts()) { |
| skyframeEventHandler.post(post); |
| } |
| if (starlarkEventHandler.hasErrors()) { |
| throw BzlLoadFailedException.executionFailed(label); |
| } |
| } |
| } |
| |
| // Precondition: thread has a valid transitiveDigest. |
| // TODO(adonovan): executeBzlFile would make a better public API than this function. |
| public static void execAndExport( |
| Program prog, Label label, EventHandler handler, Module module, StarlarkThread thread) |
| throws InterruptedException { |
| |
| // Intercept execution after every assignment at top level |
| // and "export" any newly assigned exportable globals. |
| // TODO(adonovan): change the semantics; see b/65374671. |
| thread.setPostAssignHook( |
| (name, value) -> { |
| if (value instanceof StarlarkExportable) { |
| StarlarkExportable exp = (StarlarkExportable) value; |
| if (!exp.isExported()) { |
| exp.export(handler, label, name); |
| } |
| } |
| }); |
| |
| try { |
| Starlark.execFileProgram(prog, module, thread); |
| } catch (EvalException ex) { |
| handler.handle(Event.error(null, ex.getMessageWithStack())); |
| } |
| } |
| |
| /** |
| * A manager abstracting over the method for obtaining {@code BzlCompileValue}s. See comment in |
| * {@link #create}. |
| */ |
| private interface ValueGetter { |
| @Nullable |
| BzlCompileValue getBzlCompileValue(BzlCompileValue.Key key, Environment env) |
| throws BzlCompileFunction.FailedIOException, InterruptedException; |
| |
| void doneWithBzlCompileValue(BzlCompileValue.Key key); |
| } |
| |
| /** A manager that obtains compiled .bzl files from Skyframe calls. */ |
| private static class RegularSkyframeGetter implements ValueGetter { |
| private static final RegularSkyframeGetter INSTANCE = new RegularSkyframeGetter(); |
| |
| @Nullable |
| @Override |
| public BzlCompileValue getBzlCompileValue(BzlCompileValue.Key key, Environment env) |
| throws BzlCompileFunction.FailedIOException, InterruptedException { |
| return (BzlCompileValue) env.getValueOrThrow(key, BzlCompileFunction.FailedIOException.class); |
| } |
| |
| @Override |
| public void doneWithBzlCompileValue(BzlCompileValue.Key key) {} |
| } |
| |
| /** |
| * A manager that obtains compiled .bzls by inlining {@link BzlCompileFunction} (not to be |
| * confused with inlining of {@code BzlLoadFunction}). Values are cached within the manager and |
| * released explicitly by calling {@link #doneWithBzlCompileValue}. |
| */ |
| private static class InliningAndCachingGetter implements ValueGetter { |
| private final PackageFactory packageFactory; |
| private final HashFunction hashFunction; |
| // We keep a cache of BzlCompileValues that have been computed but whose corresponding |
| // BzlLoadValue has not yet completed. This avoids repeating the BzlCompileValue work in case |
| // of Skyframe restarts. (If we weren't inlining, Skyframe would cache this for us.) |
| private final Cache<BzlCompileValue.Key, BzlCompileValue> bzlCompileCache; |
| |
| private InliningAndCachingGetter( |
| PackageFactory packageFactory, |
| HashFunction hashFunction, |
| Cache<BzlCompileValue.Key, BzlCompileValue> bzlCompileCache) { |
| this.packageFactory = packageFactory; |
| this.hashFunction = hashFunction; |
| this.bzlCompileCache = bzlCompileCache; |
| } |
| |
| @Nullable |
| @Override |
| public BzlCompileValue getBzlCompileValue(BzlCompileValue.Key key, Environment env) |
| throws BzlCompileFunction.FailedIOException, InterruptedException { |
| BzlCompileValue value = bzlCompileCache.getIfPresent(key); |
| if (value == null) { |
| value = BzlCompileFunction.computeInline(key, env, packageFactory, hashFunction); |
| if (value != null) { |
| bzlCompileCache.put(key, value); |
| } |
| } |
| return value; |
| } |
| |
| @Override |
| public void doneWithBzlCompileValue(BzlCompileValue.Key key) { |
| bzlCompileCache.invalidate(key); |
| } |
| } |
| |
| /** |
| * Per-instance manager for {@link CachedBzlLoadData}, used when {@code BzlLoadFunction} calls are |
| * inlined. |
| */ |
| private static class CachedBzlLoadDataManager { |
| private final int cacheSize; |
| private Cache<BzlLoadValue.Key, CachedBzlLoadData> cache; |
| private CachedBzlLoadDataBuilderFactory cachedDataBuilderFactory = |
| new CachedBzlLoadDataBuilderFactory(); |
| |
| private CachedBzlLoadDataManager(int cacheSize) { |
| this.cacheSize = cacheSize; |
| } |
| |
| private CachedBzlLoadData.Builder cachedDataBuilder() { |
| return cachedDataBuilderFactory.newCachedBzlLoadDataBuilder(); |
| } |
| |
| private void reset() { |
| if (cache != null) { |
| logger.atInfo().log("Starlark inlining cache stats from earlier build: %s", cache.stats()); |
| } |
| cachedDataBuilderFactory = new CachedBzlLoadDataBuilderFactory(); |
| Preconditions.checkState( |
| cacheSize >= 0, "Expected positive Starlark cache size if caching. %s", cacheSize); |
| cache = |
| Caffeine.newBuilder() |
| .initialCapacity(BlazeInterners.concurrencyLevel()) |
| .maximumSize(cacheSize) |
| .recordStats() |
| .build(); |
| } |
| } |
| |
| /** Indicates a failure to load a .bzl file. */ |
| public static final class BzlLoadFailedException extends Exception |
| implements SaneAnalysisException { |
| private final Transience transience; |
| private final DetailedExitCode detailedExitCode; |
| |
| private BzlLoadFailedException( |
| String errorMessage, DetailedExitCode detailedExitCode, Transience transience) { |
| super(errorMessage); |
| this.transience = transience; |
| this.detailedExitCode = detailedExitCode; |
| } |
| |
| private BzlLoadFailedException(String errorMessage, DetailedExitCode detailedExitCode) { |
| this(errorMessage, detailedExitCode, Transience.PERSISTENT); |
| } |
| |
| private BzlLoadFailedException( |
| String errorMessage, |
| DetailedExitCode detailedExitCode, |
| Exception cause, |
| Transience transience) { |
| super(errorMessage, cause); |
| this.transience = transience; |
| this.detailedExitCode = detailedExitCode; |
| } |
| |
| private BzlLoadFailedException(String errorMessage, Code code) { |
| this(errorMessage, createDetailedExitCode(errorMessage, code), Transience.PERSISTENT); |
| } |
| |
| private BzlLoadFailedException( |
| String errorMessage, Code code, Exception cause, Transience transience) { |
| this(errorMessage, createDetailedExitCode(errorMessage, code), cause, transience); |
| } |
| |
| Transience getTransience() { |
| return transience; |
| } |
| |
| @Override |
| public DetailedExitCode getDetailedExitCode() { |
| return detailedExitCode; |
| } |
| |
| private static DetailedExitCode createDetailedExitCode(String message, Code code) { |
| return DetailedExitCode.of( |
| FailureDetail.newBuilder() |
| .setMessage(message) |
| .setStarlarkLoading(StarlarkLoading.newBuilder().setCode(code)) |
| .build()); |
| } |
| |
| private static BzlLoadFailedException whileLoadingDep( |
| Location loc, BzlLoadFailedException cause) { |
| // Don't chain exception cause, just incorporate the message with a prefix. |
| // TODO(bazel-team): This exception should hold a Location of the requesting file's load |
| // statement, and code that catches it should use the location in the Event they create. |
| return new BzlLoadFailedException( |
| "at " + loc + ": " + cause.getMessage(), cause.getDetailedExitCode()); |
| } |
| |
| static BzlLoadFailedException executionFailed(Label label) { |
| return new BzlLoadFailedException( |
| String.format( |
| "initialization of module '%s'%s failed", |
| label.toPathFragment(), |
| StarlarkBuiltinsValue.isBuiltinsRepo(label.getRepository()) ? " (internal)" : ""), |
| Code.EVAL_ERROR); |
| } |
| |
| static BzlLoadFailedException errorFindingContainingPackage( |
| PathFragment file, Exception cause) { |
| String errorMessage = |
| String.format( |
| "Encountered error while reading extension file '%s': %s", file, cause.getMessage()); |
| DetailedExitCode detailedExitCode = |
| cause instanceof DetailedException |
| ? ((DetailedException) cause).getDetailedExitCode() |
| : createDetailedExitCode(errorMessage, Code.CONTAINING_PACKAGE_NOT_FOUND); |
| return new BzlLoadFailedException( |
| errorMessage, detailedExitCode, cause, Transience.PERSISTENT); |
| } |
| |
| static BzlLoadFailedException errorReadingBzl( |
| PathFragment file, BzlCompileFunction.FailedIOException cause) { |
| String errorMessage = |
| String.format( |
| "Encountered error while reading extension file '%s': %s", file, cause.getMessage()); |
| return new BzlLoadFailedException(errorMessage, Code.IO_ERROR, cause, cause.getTransience()); |
| } |
| |
| static BzlLoadFailedException noBuildFile(Label file, @Nullable String reason) { |
| if (reason != null) { |
| return new BzlLoadFailedException( |
| String.format("Unable to find package for %s: %s.", file, reason), |
| Code.PACKAGE_NOT_FOUND); |
| } |
| return new BzlLoadFailedException( |
| String.format( |
| "Every .bzl file must have a corresponding package, but '%s' does not have one." |
| + " Please create a BUILD file in the same or any parent directory. Note that" |
| + " this BUILD file does not need to do anything except exist.", |
| file), |
| Code.PACKAGE_NOT_FOUND); |
| } |
| |
| static BzlLoadFailedException labelCrossesPackageBoundary( |
| Label label, ContainingPackageLookupValue containingPackageLookupValue) { |
| return new BzlLoadFailedException( |
| ContainingPackageLookupValue.getErrorMessageForLabelCrossingPackageBoundary( |
| // We don't actually know the proper Root to pass in here (since we don't e.g. know |
| // the root of the bzl/BUILD file that is trying to load 'label'). Therefore we just |
| // pass in the Root of the containing package in order to still get a useful error |
| // message for the user. |
| containingPackageLookupValue.getContainingPackageRoot(), |
| label, |
| containingPackageLookupValue), |
| Code.LABEL_CROSSES_PACKAGE_BOUNDARY); |
| } |
| |
| static BzlLoadFailedException builtinsFailed(Label file, BuiltinsFailedException cause) { |
| return new BzlLoadFailedException( |
| String.format( |
| "Internal error while loading Starlark builtins for %s: %s", |
| file, cause.getMessage()), |
| Code.BUILTINS_ERROR, |
| cause, |
| cause.getTransience()); |
| } |
| } |
| |
| private static final class BzlLoadFunctionException extends SkyFunctionException { |
| private BzlLoadFunctionException(BzlLoadFailedException cause) { |
| super(cause, cause.transience); |
| } |
| } |
| } |
