// 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.remote;
import static java.nio.charset.StandardCharsets.UTF_8;
import com.google.common.collect.ImmutableList;
import com.google.common.collect.ImmutableMap;
import com.google.devtools.build.lib.actions.ActionInput;
import com.google.devtools.build.lib.actions.ExecException;
import com.google.devtools.build.lib.actions.Spawn;
import com.google.devtools.build.lib.actions.UserExecException;
import com.google.devtools.build.lib.concurrent.ThreadSafety.ThreadSafe;
import com.google.devtools.build.lib.exec.SpawnResult;
import com.google.devtools.build.lib.exec.SpawnResult.Status;
import com.google.devtools.build.lib.exec.SpawnRunner;
import com.google.devtools.build.lib.remote.ContentDigests.ActionKey;
import com.google.devtools.build.lib.remote.RemoteProtocol.Action;
import com.google.devtools.build.lib.remote.RemoteProtocol.ActionResult;
import com.google.devtools.build.lib.remote.RemoteProtocol.Command;
import com.google.devtools.build.lib.remote.RemoteProtocol.ContentDigest;
import com.google.devtools.build.lib.remote.RemoteProtocol.Platform;
import com.google.devtools.build.lib.remote.TreeNodeRepository.TreeNode;
import com.google.devtools.build.lib.util.io.FileOutErr;
import com.google.devtools.build.lib.vfs.Path;
import com.google.devtools.build.lib.vfs.PathFragment;
import com.google.protobuf.TextFormat;
import com.google.protobuf.TextFormat.ParseException;
import io.grpc.StatusRuntimeException;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Collection;
import java.util.List;
import java.util.SortedMap;
import java.util.TreeSet;
/**
* A {@link SpawnRunner} implementation that adds a remote cache on top of an underlying local
* {@link SpawnRunner} implementation.
*/
@ThreadSafe // If RemoteActionCache and SpawnRunner implementations are thread-safe.
final class CachedLocalSpawnRunner implements SpawnRunner {
private final Path execRoot;
private final RemoteOptions options;
// TODO(olaola): This will be set on a per-action basis instead.
private final Platform platform;
private final RemoteActionCache actionCache;
private final SpawnRunner delegate;
CachedLocalSpawnRunner(
Path execRoot,
RemoteOptions options,
RemoteActionCache actionCache,
SpawnRunner delegate) {
this.execRoot = execRoot;
this.options = options;
if (options.experimentalRemotePlatformOverride != null) {
Platform.Builder platformBuilder = Platform.newBuilder();
try {
TextFormat.getParser().merge(options.experimentalRemotePlatformOverride, platformBuilder);
} catch (ParseException e) {
throw new RuntimeException("Failed to parse --experimental_remote_platform_override", e);
}
platform = platformBuilder.build();
} else {
platform = null;
}
this.actionCache = actionCache;
this.delegate = delegate;
}
@Override
public SpawnResult exec(
Spawn spawn,
SpawnExecutionPolicy policy)
throws InterruptedException, IOException, ExecException {
ActionKey actionKey = null;
String mnemonic = spawn.getMnemonic();
try {
// Temporary hack: the TreeNodeRepository should be created and maintained upstream!
TreeNodeRepository repository =
new TreeNodeRepository(execRoot, policy.getActionInputFileCache());
SortedMap<PathFragment, ActionInput> inputMap = policy.getInputMapping();
TreeNode inputRoot = repository.buildFromActionInputs(inputMap);
repository.computeMerkleDigests(inputRoot);
Command command = buildCommand(spawn.getArguments(), spawn.getEnvironment());
Action action =
buildAction(
spawn.getOutputFiles(),
ContentDigests.computeDigest(command),
repository.getMerkleDigest(inputRoot));
// Look up action cache, and reuse the action output if it is found.
actionKey = ContentDigests.computeActionKey(action);
ActionResult result =
this.options.remoteAcceptCached ? actionCache.getCachedActionResult(actionKey) : null;
if (result != null) {
// We don't cache failed actions, so we know the outputs exist.
// For now, download all outputs locally; in the future, we can reuse the digests to
// just update the TreeNodeRepository and continue the build.
try {
// TODO(ulfjack): Download stdout, stderr, and the output files in a single call.
actionCache.downloadAllResults(result, execRoot);
passRemoteOutErr(result, policy.getFileOutErr());
return new SpawnResult.Builder()
.setStatus(Status.SUCCESS)
.setExitCode(result.getReturnCode())
.build();
} catch (CacheNotFoundException e) {
// TODO(ulfjack): Track down who throws this exception in what cases and double-check that
// ignoring the exception here is acceptable. Possible change it so that we throw in some
// cases - we don't want to hide failures in the remote cache from the user.
}
}
SpawnResult spawnResult = delegate.exec(spawn, policy);
if (options.remoteLocalExecUploadResults
&& spawnResult.status() == Status.SUCCESS
&& spawnResult.exitCode() == 0) {
writeCacheEntry(spawn, policy.getFileOutErr(), actionKey);
}
return spawnResult;
} catch (StatusRuntimeException e) {
throw new UserExecException(mnemonic + " remote work failed (" + e + ")", e);
}
}
private Action buildAction(
Collection<? extends ActionInput> outputs, ContentDigest command, ContentDigest inputRoot) {
Action.Builder action = Action.newBuilder();
action.setCommandDigest(command);
action.setInputRootDigest(inputRoot);
// Somewhat ugly: we rely on the stable order of outputs here for remote action caching.
for (ActionInput output : outputs) {
action.addOutputPath(output.getExecPathString());
}
if (platform != null) {
action.setPlatform(platform);
}
return action.build();
}
private static Command buildCommand(
List<String> arguments, ImmutableMap<String, String> environment) {
Command.Builder command = Command.newBuilder();
command.addAllArgv(arguments);
// Sorting the environment pairs by variable name.
TreeSet<String> variables = new TreeSet<>(environment.keySet());
for (String var : variables) {
command.addEnvironmentBuilder().setVariable(var).setValue(environment.get(var));
}
return command.build();
}
private void passRemoteOutErr(
ActionResult result, FileOutErr outErr)
throws CacheNotFoundException {
ImmutableList<byte[]> streams =
actionCache.downloadBlobs(
ImmutableList.of(result.getStdoutDigest(), result.getStderrDigest()));
outErr.printOut(new String(streams.get(0), UTF_8));
outErr.printErr(new String(streams.get(1), UTF_8));
}
private void writeCacheEntry(Spawn spawn, FileOutErr outErr, ActionKey actionKey)
throws IOException, InterruptedException {
ArrayList<Path> outputFiles = new ArrayList<>();
for (ActionInput output : spawn.getOutputFiles()) {
Path outputPath = execRoot.getRelative(output.getExecPathString());
// TODO(ulfjack): Store the actual list of output files in SpawnResult and use that instead
// of statting the files here again.
if (outputPath.exists()) {
outputFiles.add(outputPath);
}
}
ActionResult.Builder result = ActionResult.newBuilder();
actionCache.uploadAllResults(execRoot, outputFiles, result);
ContentDigest stderr = actionCache.uploadFileContents(outErr.getErrorPath());
ContentDigest stdout = actionCache.uploadFileContents(outErr.getOutputPath());
result.setStderrDigest(stderr);
result.setStdoutDigest(stdout);
actionCache.setCachedActionResult(actionKey, result.build());
}
}