| // Copyright 2018 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.config; |
| |
| import com.google.auto.value.AutoValue; |
| import com.google.common.collect.ImmutableList; |
| import com.google.common.collect.ImmutableMap; |
| import com.google.common.collect.ImmutableSet; |
| import com.google.common.collect.ImmutableSortedMap; |
| import com.google.common.collect.Sets; |
| import com.google.devtools.build.lib.analysis.config.BuildOptions; |
| import com.google.devtools.build.lib.analysis.config.InvalidConfigurationException; |
| import com.google.devtools.build.lib.cmdline.Label; |
| import java.util.Map; |
| import java.util.Set; |
| import java.util.stream.Collectors; |
| import javax.annotation.Nullable; |
| |
| /** Marker interface for detecting feature flags in the Starlark setting map. */ |
| interface FeatureFlagValue { |
| /** Returns the value of this flag, or null if it's set default. */ |
| @Nullable |
| String getValue(); |
| |
| /** A feature flag value for a flag known to be set to a particular value. */ |
| @AutoValue |
| abstract class SetValue implements FeatureFlagValue { |
| static SetValue of(String value) { |
| return new AutoValue_FeatureFlagValue_SetValue(value); |
| } |
| |
| @Override |
| public abstract String getValue(); |
| |
| @Override |
| public final String toString() { |
| return String.format("FeatureFlagValue.SetValue{%s}", getValue()); |
| } |
| } |
| |
| /** A feature flag value for a flag known to be set to its default value. */ |
| enum DefaultValue implements FeatureFlagValue { |
| INSTANCE; |
| |
| @Override |
| public String getValue() { |
| return null; |
| } |
| |
| @Override |
| public String toString() { |
| return "FeatureFlagValue.DefaultValue{}"; |
| } |
| } |
| |
| /** A feature flag value for a flag which was requested but which value was already trimmed. */ |
| enum UnknownValue implements FeatureFlagValue { |
| INSTANCE; |
| |
| @Override |
| public String getValue() { |
| throw new IllegalStateException(); |
| } |
| |
| @Override |
| public String toString() { |
| return "FeatureFlagValue.UnknownValue{}"; |
| } |
| } |
| |
| /** Returns a new BuildOptions with a new map of feature flag values. */ |
| static BuildOptions replaceFlagValues(BuildOptions original, Map<Label, String> newValues) { |
| BuildOptions.Builder result = original.toBuilder(); |
| for (Map.Entry<Label, Object> entry : original.getStarlarkOptions().entrySet()) { |
| if (entry.getValue() instanceof FeatureFlagValue) { |
| result.removeStarlarkOption(entry.getKey()); |
| } |
| } |
| ImmutableMap.Builder<Label, Object> newValueObjects = new ImmutableMap.Builder<>(); |
| for (Map.Entry<Label, String> entry : newValues.entrySet()) { |
| newValueObjects.put(entry.getKey(), SetValue.of(entry.getValue())); |
| } |
| result.addStarlarkOptions(newValueObjects.build()); |
| BuildOptions builtResult = result.build(); |
| if (builtResult.contains(ConfigFeatureFlagOptions.class)) { |
| builtResult.get(ConfigFeatureFlagOptions.class).allFeatureFlagValuesArePresent = true; |
| } |
| return builtResult; |
| } |
| |
| /** Returns a new BuildOptions with the feature flag values trimmed down to the given flags. */ |
| static BuildOptions trimFlagValues(BuildOptions original, Set<Label> availableFlags) { |
| BuildOptions.Builder result = original.toBuilder(); |
| ImmutableSet.Builder<Label> seenFlagsBuilder = new ImmutableSet.Builder<>(); |
| for (Map.Entry<Label, Object> entry : original.getStarlarkOptions().entrySet()) { |
| if (entry.getValue() instanceof FeatureFlagValue) { |
| seenFlagsBuilder.add(entry.getKey()); |
| } |
| } |
| ImmutableSet<Label> seenFlags = seenFlagsBuilder.build(); |
| for (Label trimmedFlag : Sets.difference(seenFlags, availableFlags)) { |
| result.removeStarlarkOption(trimmedFlag); |
| } |
| FeatureFlagValue unknownFlagValue = |
| (original.contains(ConfigFeatureFlagOptions.class) |
| && original.get(ConfigFeatureFlagOptions.class).allFeatureFlagValuesArePresent) |
| ? DefaultValue.INSTANCE |
| : UnknownValue.INSTANCE; |
| for (Label unknownFlag : Sets.difference(availableFlags, seenFlags)) { |
| result.addStarlarkOption(unknownFlag, unknownFlagValue); |
| } |
| BuildOptions builtResult = result.build(); |
| if (builtResult.contains(ConfigFeatureFlagOptions.class)) { |
| builtResult.get(ConfigFeatureFlagOptions.class).allFeatureFlagValuesArePresent = false; |
| } |
| return builtResult; |
| } |
| |
| /** |
| * Returns the map of known non-default flag values. Throws UnknownValueException when a flag is |
| * set to UNKNOWN_VALUE (due to an earlier trimming gone wrong). |
| */ |
| static ImmutableSortedMap<Label, String> getFlagValues(BuildOptions options) |
| throws UnknownValueException { |
| ImmutableSortedMap.Builder<Label, String> knownValues = ImmutableSortedMap.naturalOrder(); |
| ImmutableList.Builder<Label> unknownFlagsBuilder = new ImmutableList.Builder<>(); |
| for (Map.Entry<Label, Object> entry : options.getStarlarkOptions().entrySet()) { |
| if (entry.getValue().equals(UnknownValue.INSTANCE)) { |
| unknownFlagsBuilder.add(entry.getKey()); |
| } else if (entry.getValue() instanceof FeatureFlagValue) { |
| String value = ((FeatureFlagValue) entry.getValue()).getValue(); |
| if (value != null) { |
| knownValues.put(entry.getKey(), value); |
| } |
| } |
| } |
| ImmutableList<Label> unknownFlags = unknownFlagsBuilder.build(); |
| if (!unknownFlags.isEmpty()) { |
| throw new UnknownValueException(unknownFlags); |
| } |
| return knownValues.build(); |
| } |
| |
| /** Exception class for when getFlagValues runs into UNKNOWN_VALUE. */ |
| static final class UnknownValueException extends InvalidConfigurationException { |
| private static final String ERROR_TEMPLATE = |
| "Feature flag %1$s was accessed in a configuration it is not present in. All " |
| + "targets which depend on %1$s directly or indirectly must name it in their " |
| + "transitive_configs attribute."; |
| private final ImmutableList<Label> unknownFlags; |
| |
| UnknownValueException(ImmutableList<Label> unknownFlags) { |
| super( |
| "Some feature flags were incorrectly specified:\n" |
| + unknownFlags.stream() |
| .map((missingLabel) -> String.format(ERROR_TEMPLATE, missingLabel)) |
| .collect(Collectors.joining("\n"))); |
| this.unknownFlags = unknownFlags; |
| } |
| |
| ImmutableList<Label> getUnknownFlags() { |
| return unknownFlags; |
| } |
| } |
| } |