| // 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.exec; |
| |
| import com.google.common.annotations.VisibleForTesting; |
| import com.google.devtools.build.lib.actions.ActionExecutionContext; |
| import com.google.devtools.build.lib.actions.ExecException; |
| import com.google.devtools.build.lib.actions.Spawn; |
| import com.google.devtools.build.lib.actions.SpawnActionContext; |
| import com.google.devtools.build.lib.actions.SpawnContinuation; |
| import com.google.devtools.build.lib.actions.SpawnResult; |
| import com.google.devtools.build.lib.actions.UserExecException; |
| import com.google.devtools.build.lib.events.EventHandler; |
| import com.google.devtools.build.lib.events.NullEventHandler; |
| import java.util.List; |
| import java.util.stream.Collectors; |
| |
| /** Proxy that looks up the right SpawnActionContext for a spawn during {@link #exec}. */ |
| public final class ProxySpawnActionContext implements SpawnActionContext { |
| |
| private final SpawnActionContextMaps spawnActionContextMaps; |
| |
| /** |
| * Creates a new {@link ProxySpawnActionContext}. |
| * |
| * @param spawnActionContextMaps The {@link SpawnActionContextMaps} to use to decide which {@link |
| * SpawnActionContext} should execute a given {@link Spawn} during {@link #exec}. |
| */ |
| public ProxySpawnActionContext(SpawnActionContextMaps spawnActionContextMaps) { |
| this.spawnActionContextMaps = spawnActionContextMaps; |
| } |
| |
| @Override |
| public List<SpawnResult> exec(Spawn spawn, ActionExecutionContext actionExecutionContext) |
| throws ExecException, InterruptedException { |
| return resolveOne(spawn, actionExecutionContext.getEventHandler()) |
| .exec(spawn, actionExecutionContext); |
| } |
| |
| @Override |
| public SpawnContinuation beginExecution( |
| Spawn spawn, ActionExecutionContext actionExecutionContext) |
| throws ExecException, InterruptedException { |
| return resolveOne(spawn, actionExecutionContext.getEventHandler()) |
| .beginExecution(spawn, actionExecutionContext); |
| } |
| |
| private SpawnActionContext resolveOne(Spawn spawn, EventHandler eventHandler) |
| throws UserExecException { |
| List<SpawnActionContext> strategies = resolve(spawn, eventHandler); |
| |
| // Because the strategies are ordered by preference, we can execute the spawn with the best |
| // possible one by simply filtering out the ones that can't execute it and then picking the |
| // first one from the remaining strategies in the list. |
| return strategies.get(0); |
| } |
| |
| /** |
| * Returns the list of {@link SpawnActionContext}s that should be used to execute the given spawn. |
| * |
| * @param spawn The spawn for which the correct {@link SpawnActionContext} should be determined. |
| * @param eventHandler An event handler that can be used to print messages while resolving the |
| * correct {@link SpawnActionContext} for the given spawn. |
| */ |
| @VisibleForTesting |
| public List<SpawnActionContext> resolve(Spawn spawn, EventHandler eventHandler) |
| throws UserExecException { |
| List<SpawnActionContext> strategies = |
| spawnActionContextMaps.getSpawnActionContexts(spawn, eventHandler); |
| |
| strategies = |
| strategies.stream() |
| .filter(spawnActionContext -> spawnActionContext.canExec(spawn)) |
| .collect(Collectors.toList()); |
| |
| if (strategies.isEmpty()) { |
| throw new UserExecException( |
| String.format( |
| "No usable spawn strategy found for spawn with mnemonic %s. Your" |
| + " --spawn_strategy, --genrule_strategy or --strategy flags are probably too" |
| + " strict. Visit https://github.com/bazelbuild/bazel/issues/7480 for" |
| + " migration advice", |
| spawn.getMnemonic())); |
| } |
| |
| return strategies; |
| } |
| |
| @Override |
| public boolean canExec(Spawn spawn) { |
| return spawnActionContextMaps.getSpawnActionContexts(spawn, NullEventHandler.INSTANCE).stream() |
| .anyMatch(spawnActionContext -> spawnActionContext.canExec(spawn)); |
| } |
| } |