| // Copyright 2017 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.packages; |
| |
| import com.google.common.collect.ImmutableList; |
| import com.google.common.collect.ImmutableMap; |
| import com.google.devtools.build.lib.cmdline.Label; |
| import com.google.devtools.build.lib.cmdline.PackageIdentifier; |
| import com.google.devtools.build.lib.cmdline.RepositoryMapping; |
| import com.google.devtools.build.lib.events.Event; |
| import com.google.devtools.build.lib.packages.NoSuchPackageException; |
| import com.google.devtools.build.lib.packages.Package; |
| import com.google.devtools.build.lib.server.FailureDetails.FailureDetail; |
| import com.google.devtools.build.lib.skyframe.BzlLoadFailedException; |
| import com.google.devtools.build.lib.skyframe.DetailedException; |
| import com.google.devtools.build.lib.util.ValueOrException; |
| import java.util.Optional; |
| import javax.annotation.concurrent.NotThreadSafe; |
| import net.starlark.java.eval.Module; |
| |
| /** A standalone library for performing Bazel package loading. */ |
| public interface PackageLoader extends AutoCloseable { |
| /** |
| * Loads and returns a single package. This method is a simplified shorthand for {@link |
| * LoadingContext#loadPackages} when just a single {@link Package} and nothing else is desired. |
| */ |
| Package loadPackage(PackageIdentifier pkgId) throws NoSuchPackageException, InterruptedException; |
| |
| /** |
| * A reusable context for loading packages and Starlark modules (.bzl or .scl files). |
| * |
| * <p>Instances of this class are not thread-safe; but the values loaded and returned by its |
| * methods are thread-safe. The intention is for LoadingContext to be used e.g. as a local |
| * variable in a single-threaded wrapper method of a higher-level abstraction. |
| */ |
| @NotThreadSafe |
| interface LoadingContext { |
| /** |
| * Returns the result of loading a collection of packages. Note that the returned {@link |
| * Package}s may contain errors - see {@link Package#containsErrors()} for details. |
| * |
| * <p>A call to this method clears the list of events accumulated by previous {@link |
| * #loadPackages} and {@link #loadModules} calls. |
| */ |
| Result<PackageIdentifier, Package, NoSuchPackageException> loadPackages( |
| Iterable<PackageIdentifier> pkgIds) throws InterruptedException; |
| |
| /** |
| * Returns the result of loading a collection of Starlark modules (i.e. .bzl or .scl files); |
| * intended for use by standalone implementations of the starlark_doc_extract rule. |
| * |
| * <p>A call to this method clears the list of events accumulated by previous {@link |
| * #loadPackages} and {@link #loadModules} calls. |
| */ |
| Result<Label, Module, StarlarkModuleLoadingException> loadModules(Iterable<Label> labels) |
| throws InterruptedException; |
| |
| /** |
| * Returns the main repository's repository mapping. |
| * |
| * <p>Intended to be used for stringifying labels in loaded modules in standalone |
| * implementations of the starlark_doc_extract rule. |
| */ |
| RepositoryMapping getRepositoryMapping() throws InterruptedException; |
| } |
| |
| /** An exception thrown when we fail to load a Starlark module. */ |
| class StarlarkModuleLoadingException extends Exception { |
| StarlarkModuleLoadingException(String message) { |
| super(message); |
| } |
| |
| StarlarkModuleLoadingException(BzlLoadFailedException cause) { |
| super(cause); |
| } |
| |
| /** The {@link FailureDetail} of the underlying exception, if one is available. */ |
| Optional<FailureDetail> getFailureDetail() { |
| if (getCause() instanceof DetailedException) { |
| return Optional.of( |
| ((DetailedException) getCause()).getDetailedExitCode().getFailureDetail()); |
| } else { |
| return Optional.empty(); |
| } |
| } |
| } |
| |
| /** Returns a new {@link LoadingContext}. */ |
| LoadingContext makeLoadingContext() throws InterruptedException; |
| |
| /** |
| * Shut down the internal threadpools used by the {@link PackageLoader}. |
| * |
| * <p>Call this method when you are completely done with the {@link PackageLoader} instance, |
| * otherwise there may be resource leaks. |
| */ |
| @Override |
| void close(); |
| |
| /** |
| * Contains the result of a {@link LoadingContext#loadPackages} or {@link |
| * LoadingContext#loadModules} call. |
| */ |
| class Result<K, V, E extends Exception> { |
| private final ImmutableMap<K, ValueOrException<V, E>> loadedValues; |
| private final ImmutableList<Event> events; |
| |
| Result(ImmutableMap<K, ValueOrException<V, E>> loadedValues, ImmutableList<Event> events) { |
| this.loadedValues = loadedValues; |
| this.events = events; |
| } |
| |
| /** |
| * Returns the map from the requested keys to the corresponding values (packages or modules) |
| * which were loaded, or exceptions encountered while attempting to load a given value. |
| */ |
| public ImmutableMap<K, ValueOrException<V, E>> getLoadedValues() { |
| return loadedValues; |
| } |
| |
| /** |
| * Returns the events generated by the {@link LoadingContext#loadPackages} or {@link |
| * LoadingContext#loadModules} call. |
| */ |
| public ImmutableList<Event> getEvents() { |
| return events; |
| } |
| } |
| } |