| // 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.rules.android; |
| |
| import com.google.common.base.Optional; |
| import com.google.common.collect.ImmutableMap; |
| import com.google.devtools.build.lib.analysis.AliasProvider; |
| import com.google.devtools.build.lib.analysis.RuleContext; |
| import com.google.devtools.build.lib.analysis.RuleDefinitionEnvironment; |
| import com.google.devtools.build.lib.analysis.TransitiveInfoCollection; |
| import com.google.devtools.build.lib.analysis.configuredtargets.RuleConfiguredTarget.Mode; |
| import com.google.devtools.build.lib.cmdline.Label; |
| import com.google.devtools.build.lib.concurrent.ThreadSafety.Immutable; |
| import com.google.devtools.build.lib.packages.Attribute; |
| import com.google.devtools.build.lib.packages.BuildType; |
| import com.google.devtools.build.lib.packages.BuiltinProvider; |
| import com.google.devtools.build.lib.packages.NativeInfo; |
| import com.google.devtools.build.lib.packages.NonconfigurableAttributeMapper; |
| import com.google.devtools.build.lib.packages.RuleClass.ConfiguredTargetFactory.RuleErrorException; |
| import com.google.devtools.build.lib.rules.config.ConfigFeatureFlag; |
| import com.google.devtools.build.lib.skylarkbuildapi.android.AndroidFeatureFlagSetProviderApi; |
| import com.google.devtools.build.lib.syntax.Dict; |
| import com.google.devtools.build.lib.syntax.EvalException; |
| import java.util.Map; |
| |
| /** |
| * Provider for checking the set of feature flags used by an android_binary. |
| * |
| * <p>Because the feature flags are completely replaced by android_binary, android_test uses this |
| * provider to ensure that the test sets the same flags as the binary. Otherwise, the dependencies |
| * of the android_test will be compiled with different flags from the android_binary code which runs |
| * in the same Android virtual machine, which may cause compatibility issues at runtime. |
| */ |
| @Immutable |
| public final class AndroidFeatureFlagSetProvider extends NativeInfo |
| implements AndroidFeatureFlagSetProviderApi { |
| |
| public static final Provider PROVIDER = new Provider(); |
| |
| /** The name of the attribute used by Android rules to set config_feature_flags. */ |
| public static final String FEATURE_FLAG_ATTR = "feature_flags"; |
| |
| private final Optional<ImmutableMap<Label, String>> flags; |
| |
| AndroidFeatureFlagSetProvider(Optional<? extends Map<Label, String>> flags) { |
| super(PROVIDER); |
| this.flags = flags.transform(ImmutableMap::copyOf); |
| } |
| |
| public static AndroidFeatureFlagSetProvider create(Optional<? extends Map<Label, String>> flags) { |
| return new AndroidFeatureFlagSetProvider(flags.transform(ImmutableMap::copyOf)); |
| } |
| |
| /** |
| * Constructs a definition for the attribute used to restrict access to feature flags. The |
| * whitelist will only be reached if the feature_flags attribute is explicitly set. |
| */ |
| public static Attribute.Builder<Label> getWhitelistAttribute(RuleDefinitionEnvironment env) { |
| return ConfigFeatureFlag.getWhitelistAttribute(env, FEATURE_FLAG_ATTR); |
| } |
| |
| /** |
| * Builds a map which can be used with create, confirming that the desired flag values were |
| * actually received, and producing an error if they were not (because aliases were used). |
| * |
| * <p>If the attribute which defines feature flags was not specified, an empty {@link Optional} |
| * instance is returned. |
| */ |
| public static Optional<ImmutableMap<Label, String>> getAndValidateFlagMapFromRuleContext( |
| RuleContext ruleContext) throws RuleErrorException { |
| NonconfigurableAttributeMapper attrs = NonconfigurableAttributeMapper.of(ruleContext.getRule()); |
| |
| if (!attrs.isAttributeValueExplicitlySpecified(FEATURE_FLAG_ATTR)) { |
| return Optional.absent(); |
| } |
| |
| Map<Label, String> expectedValues = |
| attrs.get(FEATURE_FLAG_ATTR, BuildType.LABEL_KEYED_STRING_DICT); |
| if (expectedValues.isEmpty()) { |
| return Optional.of(ImmutableMap.of()); |
| } |
| |
| if (!ConfigFeatureFlag.isAvailable(ruleContext)) { |
| ruleContext.attributeError( |
| FEATURE_FLAG_ATTR, |
| String.format( |
| "the %s attribute is not available in package '%s'", |
| FEATURE_FLAG_ATTR, ruleContext.getLabel().getPackageIdentifier())); |
| throw new RuleErrorException(); |
| } |
| |
| Iterable<? extends TransitiveInfoCollection> actualTargets = |
| ruleContext.getPrerequisites(FEATURE_FLAG_ATTR, Mode.TARGET); |
| boolean aliasFound = false; |
| for (TransitiveInfoCollection target : actualTargets) { |
| Label label = AliasProvider.getDependencyLabel(target); |
| if (!label.equals(target.getLabel())) { |
| ruleContext.attributeError( |
| FEATURE_FLAG_ATTR, |
| String.format( |
| "Feature flags must be named directly, not through aliases; use '%s', not '%s'", |
| target.getLabel(), label)); |
| aliasFound = true; |
| } |
| } |
| if (aliasFound) { |
| throw new RuleErrorException(); |
| } |
| return Optional.of(ImmutableMap.copyOf(expectedValues)); |
| } |
| |
| /** |
| * Returns whether it is acceptable to have a dependency with flags {@code depFlags} if the target |
| * has flags {@code targetFlags}. |
| */ |
| public static boolean isValidDependency( |
| Optional<? extends Map<Label, String>> targetFlags, |
| Optional<? extends Map<Label, String>> depFlags) { |
| return !depFlags.isPresent() |
| || (targetFlags.isPresent() && targetFlags.get().equals(depFlags.get())); |
| } |
| |
| public Optional<ImmutableMap<Label, String>> getFlags() { |
| return flags; |
| } |
| |
| @Override |
| public ImmutableMap<Label, String> getFlagMap() { |
| return flags.or(ImmutableMap.of()); |
| } |
| |
| /** Provider class for {@link AndroidFeatureFlagSetProvider} objects. */ |
| public static class Provider extends BuiltinProvider<AndroidFeatureFlagSetProvider> |
| implements AndroidFeatureFlagSetProviderApi.Provider { |
| private Provider() { |
| super(NAME, AndroidFeatureFlagSetProvider.class); |
| } |
| |
| public String getName() { |
| return NAME; |
| } |
| |
| @Override |
| public AndroidFeatureFlagSetProvider create(Dict<?, ?> flags) // <Label, String> |
| throws EvalException { |
| return new AndroidFeatureFlagSetProvider( |
| Optional.of(Dict.castSkylarkDictOrNoneToDict(flags, Label.class, String.class, "flags"))); |
| } |
| } |
| } |