Move most of the workspace-handling code from BlazeRuntime to a new class.

--
MOS_MIGRATED_REVID=118563271

9 files changed, 323 insertions, 248 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/buildtool/BuildTool.java b/src/main/java/com/google/devtools/build/lib/buildtool/BuildTool.java
index 7da7e2872e..7523cc217b 100644
--- a/src/main/java/com/google/devtools/build/lib/buildtool/BuildTool.java
+++ b/src/main/java/com/google/devtools/build/lib/buildtool/BuildTool.java
@@ -176,7 +176,7 @@ public final class BuildTool {
               + "'test' right now!");
         }
       }
-      configurations = runtime.getSkyframeExecutor().createConfigurations(
+      configurations = env.getSkyframeExecutor().createConfigurations(
             env.getReporter(), runtime.getConfigurationFactory(), buildOptions,
             env.getDirectories(), request.getMultiCpus(), request.getViewOptions().keepGoing);
 
@@ -204,7 +204,7 @@ public final class BuildTool {
 
       // Execution phase.
       if (needsExecutionPhase(request.getBuildOptions())) {
-        runtime.getSkyframeExecutor().injectTopLevelContext(request.getTopLevelArtifactContext());
+        env.getSkyframeExecutor().injectTopLevelContext(request.getTopLevelArtifactContext());
         executionTool.executeBuild(request.getId(), analysisResult, result,
             configurations, transformPackageRoots(analysisResult.getPackageRoots()));
       }
@@ -228,7 +228,7 @@ public final class BuildTool {
         // Delete dirty nodes to ensure that they do not accumulate indefinitely.
         long versionWindow = request.getViewOptions().versionWindowForDirtyNodeGc;
         if (versionWindow != -1) {
-          runtime.getSkyframeExecutor().deleteOldNodes(versionWindow);
+          env.getSkyframeExecutor().deleteOldNodes(versionWindow);
         }
 
         if (executionTool != null) {
@@ -413,11 +413,11 @@ public final class BuildTool {
 
       @Override
       public void notifyVisitedPackages(Set<PackageIdentifier> visitedPackages) {
-        runtime.getSkyframeExecutor().updateLoadedPackageSet(visitedPackages);
+        env.getSkyframeExecutor().updateLoadedPackageSet(visitedPackages);
       }
     };
 
-    LoadingPhaseRunner loadingPhaseRunner = runtime.getSkyframeExecutor().getLoadingPhaseRunner(
+    LoadingPhaseRunner loadingPhaseRunner = env.getSkyframeExecutor().getLoadingPhaseRunner(
         runtime.getPackageFactory().getRuleClassNames(),
         request.getLoadingOptions().useSkyframeTargetPatternEvaluator);
     LoadingResult result = loadingPhaseRunner.execute(getReporter(),
@@ -464,7 +464,7 @@ public final class BuildTool {
     Profiler.instance().markPhase(ProfilePhase.ANALYZE);
 
     BuildView view = new BuildView(env.getDirectories(), runtime.getRuleClassProvider(),
-        runtime.getSkyframeExecutor(), runtime.getCoverageReportActionFactory());
+        env.getSkyframeExecutor(), runtime.getCoverageReportActionFactory());
     AnalysisResult analysisResult =
         view.update(
             loadingResult,
diff --git a/src/main/java/com/google/devtools/build/lib/buildtool/ExecutionTool.java b/src/main/java/com/google/devtools/build/lib/buildtool/ExecutionTool.java
index 0b1e95ba43..f4da845e8f 100644
--- a/src/main/java/com/google/devtools/build/lib/buildtool/ExecutionTool.java
+++ b/src/main/java/com/google/devtools/build/lib/buildtool/ExecutionTool.java
@@ -437,7 +437,7 @@ public class ExecutionTool {
           executor,
           builtTargets,
           request.getBuildOptions().explanationPath != null,
-          runtime.getLastExecutionTimeRange());
+          env.getBlazeWorkspace().getLastExecutionTimeRange());
       buildCompleted = true;
     } catch (BuildFailedException | TestExecException e) {
       buildCompleted = true;
diff --git a/src/main/java/com/google/devtools/build/lib/runtime/BlazeCommandDispatcher.java b/src/main/java/com/google/devtools/build/lib/runtime/BlazeCommandDispatcher.java
index ad45de4b62..97cdbdd0b5 100644
--- a/src/main/java/com/google/devtools/build/lib/runtime/BlazeCommandDispatcher.java
+++ b/src/main/java/com/google/devtools/build/lib/runtime/BlazeCommandDispatcher.java
@@ -143,7 +143,7 @@ public class BlazeCommandDispatcher {
     }
 
     Path doNotBuild = workspace.getParentDirectory().getRelative(
-        BlazeRuntime.DO_NOT_BUILD_FILE_NAME);
+        BlazeWorkspace.DO_NOT_BUILD_FILE_NAME);
 
     if (doNotBuild.exists()) {
       if (!commandAnnotation.canRunInOutputDirectory()) {
@@ -319,7 +319,7 @@ public class BlazeCommandDispatcher {
 
     // Do this before an actual crash so we don't have to worry about
     // allocating memory post-crash.
-    String[] crashData = runtime.getCrashData(env);
+    String[] crashData = env.getCrashData();
     int numericExitCode = ExitCode.BLAZE_INTERNAL_ERROR.getNumericExitCode();
     PrintStream savedOut = System.out;
     PrintStream savedErr = System.err;
diff --git a/src/main/java/com/google/devtools/build/lib/runtime/BlazeRuntime.java b/src/main/java/com/google/devtools/build/lib/runtime/BlazeRuntime.java
index 638e5f964f..fc736b5a8d 100644
--- a/src/main/java/com/google/devtools/build/lib/runtime/BlazeRuntime.java
+++ b/src/main/java/com/google/devtools/build/lib/runtime/BlazeRuntime.java
@@ -14,9 +14,6 @@
 
 package com.google.devtools.build.lib.runtime;
 
-import static com.google.devtools.build.lib.profiler.AutoProfiler.profiledAndLogged;
-import static java.nio.charset.StandardCharsets.ISO_8859_1;
-
 import com.google.common.annotations.VisibleForTesting;
 import com.google.common.base.Function;
 import com.google.common.base.Predicate;
@@ -25,16 +22,12 @@ import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
 import com.google.common.collect.Iterables;
 import com.google.common.collect.Lists;
-import com.google.common.collect.Range;
 import com.google.common.collect.Sets;
 import com.google.common.eventbus.EventBus;
 import com.google.common.eventbus.SubscriberExceptionContext;
 import com.google.common.eventbus.SubscriberExceptionHandler;
 import com.google.common.util.concurrent.Futures;
 import com.google.common.util.concurrent.Uninterruptibles;
-import com.google.devtools.build.lib.actions.cache.ActionCache;
-import com.google.devtools.build.lib.actions.cache.CompactPersistentActionCache;
-import com.google.devtools.build.lib.actions.cache.NullActionCache;
 import com.google.devtools.build.lib.analysis.BlazeDirectories;
 import com.google.devtools.build.lib.analysis.BlazeVersionInfo;
 import com.google.devtools.build.lib.analysis.ConfiguredRuleClassProvider;
@@ -44,11 +37,9 @@ import com.google.devtools.build.lib.analysis.config.BuildOptions;
 import com.google.devtools.build.lib.analysis.config.ConfigurationFactory;
 import com.google.devtools.build.lib.events.Event;
 import com.google.devtools.build.lib.events.OutputFilter;
-import com.google.devtools.build.lib.events.Reporter;
 import com.google.devtools.build.lib.packages.PackageFactory;
 import com.google.devtools.build.lib.packages.Preprocessor;
 import com.google.devtools.build.lib.packages.RuleClassProvider;
-import com.google.devtools.build.lib.pkgcache.PackageManager;
 import com.google.devtools.build.lib.profiler.AutoProfiler;
 import com.google.devtools.build.lib.profiler.MemoryProfiler;
 import com.google.devtools.build.lib.profiler.ProfilePhase;
@@ -93,7 +84,6 @@ import com.google.devtools.build.lib.util.Preconditions;
 import com.google.devtools.build.lib.util.ThreadUtils;
 import com.google.devtools.build.lib.util.io.OutErr;
 import com.google.devtools.build.lib.vfs.FileSystem;
-import com.google.devtools.build.lib.vfs.FileSystemUtils;
 import com.google.devtools.build.lib.vfs.JavaIoFileSystem;
 import com.google.devtools.build.lib.vfs.Path;
 import com.google.devtools.build.lib.vfs.PathFragment;
@@ -144,8 +134,6 @@ import javax.annotation.Nullable;
  * <p>The parts specific to the current command are stored in {@link CommandEnvironment}.
  */
 public final class BlazeRuntime {
-  public static final String DO_NOT_BUILD_FILE_NAME = "DO_NOT_BUILD_HERE";
-
   private static final Pattern suppressFromLog = Pattern.compile(".*(auth|pass|cookie).*",
       Pattern.CASE_INSENSITIVE);
 
@@ -173,13 +161,7 @@ public final class BlazeRuntime {
   private final QueryEnvironmentFactory queryEnvironmentFactory;
 
   // Workspace state (currently exactly one workspace per server)
-  private final BlazeDirectories directories;
-  private final SkyframeExecutor skyframeExecutor;
-  /** The action cache is loaded lazily on the first build command. */
-  private ActionCache actionCache;
-  /** The execution time range of the previous build command in this server, if any. */
-  @Nullable
-  private Range<Long> lastExecutionRange = null;
+  private final BlazeWorkspace workspace;
 
   private BlazeRuntime(BlazeDirectories directories,
       WorkspaceStatusAction.Factory workspaceStatusActionFactory,
@@ -209,14 +191,7 @@ public final class BlazeRuntime {
     this.queryEnvironmentFactory = queryEnvironmentFactory;
 
     // Workspace state
-    this.directories = directories;
-    this.skyframeExecutor = skyframeExecutor;
-
-    if (directories.inWorkspace()) {
-      writeOutputBaseReadmeFile();
-      writeDoNotBuildHereFile();
-    }
-    setupExecRoot();
+    this.workspace = new BlazeWorkspace(this, directories, skyframeExecutor);
   }
 
   private static InvocationPolicy createInvocationPolicyFromModules(
@@ -274,17 +249,11 @@ public final class BlazeRuntime {
 
   public CommandEnvironment initCommand() {
     EventBus eventBus = new EventBus(eventBusExceptionHandler);
-    skyframeExecutor.setEventBus(eventBus);
+    workspace.getSkyframeExecutor().setEventBus(eventBus);
     UUID commandId = UUID.randomUUID();
     return new CommandEnvironment(this, commandId, eventBus);
   }
 
-  private void clearEventBus() {
-    // EventBus does not have an unregister() method, so this is how we release memory associated
-    // with handlers.
-    skyframeExecutor.setEventBus(null);
-  }
-
   @Nullable
   public InvocationPolicy getInvocationPolicy() {
     return invocationPolicy;
@@ -301,7 +270,7 @@ public final class BlazeRuntime {
 
     try {
       if (options.profilePath != null) {
-        Path profilePath = getWorkspace().getRelative(options.profilePath);
+        Path profilePath = env.getWorkspace().getRelative(options.profilePath);
 
         recordFullProfilerData = options.recordFullProfilerData;
         out = new BufferedOutputStream(profilePath.getOutputStream(), 1024 * 1024);
@@ -314,7 +283,7 @@ public final class BlazeRuntime {
       }
       if (profiledTasks != ProfiledTaskKinds.NONE) {
         Profiler.instance().start(profiledTasks, out,
-            "Blaze profile for " + getOutputBase() + " at " + new Date()
+            "Blaze profile for " + env.getOutputBase() + " at " + new Date()
             + ", build ID: " + buildID,
             recordFullProfilerData, clock, execStartTimeNanos);
         return true;
@@ -325,101 +294,8 @@ public final class BlazeRuntime {
     return false;
   }
 
-  /**
-   * Generates a README file in the output base directory. This README file
-   * contains the name of the workspace directory, so that users can figure out
-   * which output base directory corresponds to which workspace.
-   */
-  private void writeOutputBaseReadmeFile() {
-    Preconditions.checkNotNull(getWorkspace());
-    Path outputBaseReadmeFile = getOutputBase().getRelative("README");
-    try {
-      FileSystemUtils.writeIsoLatin1(outputBaseReadmeFile, "WORKSPACE: " + getWorkspace(), "",
-          "The first line of this file is intentionally easy to parse for various",
-          "interactive scripting and debugging purposes.  But please DO NOT write programs",
-          "that exploit it, as they will be broken by design: it is not possible to",
-          "reverse engineer the set of source trees or the --package_path from the output",
-          "tree, and if you attempt it, you will fail, creating subtle and",
-          "hard-to-diagnose bugs, that will no doubt get blamed on changes made by the",
-          "Blaze team.", "", "This directory was generated by Blaze.",
-          "Do not attempt to modify or delete any files in this directory.",
-          "Among other issues, Blaze's file system caching assumes that",
-          "only Blaze will modify this directory and the files in it,",
-          "so if you change anything here you may mess up Blaze's cache.");
-    } catch (IOException e) {
-      LOG.warning("Couldn't write to '" + outputBaseReadmeFile + "': " + e.getMessage());
-    }
-  }
-
-  private void writeDoNotBuildHereFile(Path filePath) {
-    try {
-      FileSystemUtils.createDirectoryAndParents(filePath.getParentDirectory());
-      FileSystemUtils.writeContent(filePath, ISO_8859_1, getWorkspace().toString());
-    } catch (IOException e) {
-      LOG.warning("Couldn't write to '" + filePath + "': " + e.getMessage());
-    }
-  }
-
-  private void writeDoNotBuildHereFile() {
-    Preconditions.checkNotNull(getWorkspace());
-    writeDoNotBuildHereFile(getOutputBase().getRelative(DO_NOT_BUILD_FILE_NAME));
-    if (startupOptionsProvider.getOptions(BlazeServerStartupOptions.class).deepExecRoot) {
-      writeDoNotBuildHereFile(getOutputBase().getRelative("execroot").getRelative(
-          DO_NOT_BUILD_FILE_NAME));
-    }
-  }
-
-  /**
-   * Creates the execRoot dir under outputBase.
-   */
-  private void setupExecRoot() {
-    try {
-      FileSystemUtils.createDirectoryAndParents(directories.getExecRoot());
-    } catch (IOException e) {
-      LOG.warning("failed to create execution root '" + directories.getExecRoot() + "': "
-          + e.getMessage());
-    }
-  }
-
-  void recordLastExecutionTime(long commandStartTime) {
-    long currentTimeMillis = clock.currentTimeMillis();
-    lastExecutionRange = currentTimeMillis >= commandStartTime
-        ? Range.closed(commandStartTime, currentTimeMillis)
-        : null;
-  }
-
-  /**
-   * Range that represents the last execution time of a build in millis since epoch.
-   */
-  @Nullable
-  public Range<Long> getLastExecutionTimeRange() {
-    return lastExecutionRange;
-  }
-
-  /**
-   * Returns the Blaze directories object for this runtime.
-   */
-  public BlazeDirectories getDirectories() {
-    return directories;
-  }
-
-  /**
-   * Returns the working directory of the server.
-   *
-   * <p>This is often the first entry on the {@code --package_path}, but not always.
-   * Callers should certainly not make this assumption. The Path returned may be null.
-   */
-  private Path getWorkspace() {
-    return directories.getWorkspace();
-  }
-
-  /**
-   * Returns the output base directory associated with this Blaze server
-   * process. This is the base directory for shared Blaze state as well as tool
-   * and strategy specific subdirectories.
-   */
-  private Path getOutputBase() {
-    return directories.getOutputBase();
+  public BlazeWorkspace getWorkspace() {
+    return workspace;
   }
 
   /**
@@ -427,7 +303,7 @@ public final class BlazeRuntime {
    * file and a log.
    */
   private Path getServerDirectory() {
-    return getDirectories().getOutputBase().getChild("server");
+    return getWorkspace().getDirectories().getOutputBase().getChild("server");
   }
 
   public BinTools getBinTools() {
@@ -435,13 +311,6 @@ public final class BlazeRuntime {
   }
 
   /**
-   * Returns the skyframe executor.
-   */
-  public SkyframeExecutor getSkyframeExecutor() {
-    return skyframeExecutor;
-  }
-
-  /**
    * Returns the {@link QueryEnvironmentFactory} that should be used to create a
    * {@link AbstractBlazeQueryEnvironment}, whenever one is needed.
    */
@@ -466,13 +335,6 @@ public final class BlazeRuntime {
     return result.build();
   }
 
-  /**
-   * Returns the package manager.
-   */
-  public PackageManager getPackageManager() {
-    return skyframeExecutor.getPackageManager();
-  }
-
   public WorkspaceStatusAction.Factory getworkspaceStatusActionFactory() {
     return workspaceStatusActionFactory;
   }
@@ -504,55 +366,6 @@ public final class BlazeRuntime {
   }
 
   /**
-   * Returns reference to the lazily instantiated persistent action cache
-   * instance. Note, that method may recreate instance between different build
-   * requests, so return value should not be cached.
-   */
-  public ActionCache getPersistentActionCache(Reporter reporter) throws IOException {
-    if (actionCache == null) {
-      if (OS.getCurrent() == OS.WINDOWS) {
-        // TODO(bazel-team): Add support for a persistent action cache on Windows.
-        actionCache = new NullActionCache();
-        return actionCache;
-      }
-      try (AutoProfiler p = profiledAndLogged("Loading action cache", ProfilerTask.INFO, LOG)) {
-        try {
-          actionCache = new CompactPersistentActionCache(getCacheDirectory(), clock);
-        } catch (IOException e) {
-          LOG.log(Level.WARNING, "Failed to load action cache: " + e.getMessage(), e);
-          LoggingUtil.logToRemote(Level.WARNING, "Failed to load action cache: "
-              + e.getMessage(), e);
-          reporter.handle(
-              Event.error("Error during action cache initialization: " + e.getMessage()
-              + ". Corrupted files were renamed to '" + getCacheDirectory() + "/*.bad'. "
-              + "Blaze will now reset action cache data, causing a full rebuild"));
-          actionCache = new CompactPersistentActionCache(getCacheDirectory(), clock);
-        }
-      }
-    }
-    return actionCache;
-  }
-
-  /**
-   * Removes in-memory caches.
-   */
-  public void clearCaches() throws IOException {
-    skyframeExecutor.resetEvaluator();
-    actionCache = null;
-    FileSystemUtils.deleteTree(getCacheDirectory());
-  }
-
-  /**
-   * Returns path to the cache directory. Path must be inside output base to
-   * ensure that users can run concurrent instances of blaze in different
-   * clients without attempting to concurrently write to the same action cache
-   * on disk, which might not be safe.
-   */
-  private Path getCacheDirectory() {
-    return getOutputBase().getChild("action_cache");
-  }
-
-  /**
    * Returns a provider for project file objects. Can be null if no such provider was set by any of
    * the modules.
    */
@@ -610,7 +423,7 @@ public final class BlazeRuntime {
       // thread won the race (unlikely, but possible), this may be incorrectly logged as a success.
       return;
     }
-    skyframeExecutor.getEventBus().post(new CommandCompleteEvent(exitCode));
+    workspace.getSkyframeExecutor().getEventBus().post(new CommandCompleteEvent(exitCode));
   }
 
   /**
@@ -628,7 +441,7 @@ public final class BlazeRuntime {
       module.afterCommand();
     }
 
-    clearEventBus();
+    env.getBlazeWorkspace().clearEventBus();
 
     try {
       Profiler.instance().stop();
@@ -671,26 +484,6 @@ public final class BlazeRuntime {
     return startupOptionsProvider;
   }
 
-  /**
-   * An array of String values useful if Blaze crashes.
-   * For now, just returns the size of the action cache and the build id.
-   */
-  public String[] getCrashData(CommandEnvironment env) {
-    return new String[]{
-        getFileSizeString(CompactPersistentActionCache.cacheFile(getCacheDirectory()),
-                          "action cache"),
-        env.getCommandId() + " (build id)",
-    };
-  }
-
-  private String getFileSizeString(Path path, String type) {
-    try {
-      return String.format("%d bytes (%s)", path.getFileSize(), type);
-    } catch (IOException e) {
-      return String.format("unknown file size (%s)", type);
-    }
-  }
-
   public Map<String, BlazeCommand> getCommandMap() {
     return commandMap;
   }
@@ -1034,7 +827,8 @@ public final class BlazeRuntime {
     };
 
     RPCServer server = RPCServer.newServerWith(runtime.getClock(), blazeCommand,
-        runtime.getServerDirectory(), runtime.getWorkspace(), startupOptions.maxIdleSeconds);
+        runtime.getServerDirectory(), runtime.workspace.getWorkspace(),
+        startupOptions.maxIdleSeconds);
     return server;
   }
 
diff --git a/src/main/java/com/google/devtools/build/lib/runtime/BlazeWorkspace.java b/src/main/java/com/google/devtools/build/lib/runtime/BlazeWorkspace.java
new file mode 100644
index 0000000000..65ba1acd6a
--- /dev/null
+++ b/src/main/java/com/google/devtools/build/lib/runtime/BlazeWorkspace.java
@@ -0,0 +1,254 @@
+// Copyright 2016 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.runtime;
+
+import static com.google.devtools.build.lib.profiler.AutoProfiler.profiledAndLogged;
+import static java.nio.charset.StandardCharsets.ISO_8859_1;
+
+import com.google.common.collect.Range;
+import com.google.devtools.build.lib.actions.cache.ActionCache;
+import com.google.devtools.build.lib.actions.cache.CompactPersistentActionCache;
+import com.google.devtools.build.lib.actions.cache.NullActionCache;
+import com.google.devtools.build.lib.analysis.BlazeDirectories;
+import com.google.devtools.build.lib.events.Event;
+import com.google.devtools.build.lib.events.Reporter;
+import com.google.devtools.build.lib.profiler.AutoProfiler;
+import com.google.devtools.build.lib.profiler.ProfilerTask;
+import com.google.devtools.build.lib.skyframe.SkyframeExecutor;
+import com.google.devtools.build.lib.util.LoggingUtil;
+import com.google.devtools.build.lib.util.OS;
+import com.google.devtools.build.lib.util.Preconditions;
+import com.google.devtools.build.lib.vfs.FileSystemUtils;
+import com.google.devtools.build.lib.vfs.Path;
+import com.google.devtools.common.options.OptionsProvider;
+
+import java.io.IOException;
+import java.util.logging.Level;
+import java.util.logging.Logger;
+
+import javax.annotation.Nullable;
+
+/**
+ * This class represents a workspace, and contains operations and data related to it. In contrast,
+ * the BlazeRuntime class represents the Blaze server, and contains operations and data that are
+ * (supposed to be) independent of the workspace or the current command.
+ *
+ * <p>At this time, there is still a 1:1 relationship between the BlazeRuntime and the
+ * BlazeWorkspace, but the introduction of this class is a step towards allowing 1:N relationships.
+ */
+public final class BlazeWorkspace {
+  public static final String DO_NOT_BUILD_FILE_NAME = "DO_NOT_BUILD_HERE";
+
+  private static final Logger LOG = Logger.getLogger(BlazeRuntime.class.getName());
+
+  private final BlazeRuntime runtime;
+
+  private final BlazeDirectories directories;
+  private final SkyframeExecutor skyframeExecutor;
+  /** The action cache is loaded lazily on the first build command. */
+  private ActionCache actionCache;
+  /** The execution time range of the previous build command in this server, if any. */
+  @Nullable
+  private Range<Long> lastExecutionRange = null;
+
+  public BlazeWorkspace(
+      BlazeRuntime runtime, BlazeDirectories directories, SkyframeExecutor skyframeExecutor) {
+    this.runtime = runtime;
+    this.directories = directories;
+    this.skyframeExecutor = skyframeExecutor;
+
+    if (directories.inWorkspace()) {
+      writeOutputBaseReadmeFile();
+      writeDoNotBuildHereFile(runtime.getStartupOptionsProvider());
+    }
+    setupExecRoot();
+  }
+
+  /**
+   * Returns the Blaze directories object for this runtime.
+   */
+  public BlazeDirectories getDirectories() {
+    return directories;
+  }
+
+  public SkyframeExecutor getSkyframeExecutor() {
+    return skyframeExecutor;
+  }
+
+  /**
+   * Returns the working directory of the server.
+   *
+   * <p>This is often the first entry on the {@code --package_path}, but not always.
+   * Callers should certainly not make this assumption. The Path returned may be null.
+   */
+  public Path getWorkspace() {
+    return directories.getWorkspace();
+  }
+
+  /**
+   * Returns the output base directory associated with this Blaze server
+   * process. This is the base directory for shared Blaze state as well as tool
+   * and strategy specific subdirectories.
+   */
+  public Path getOutputBase() {
+    return directories.getOutputBase();
+  }
+
+  /**
+   * Returns the output path associated with this Blaze server process..
+   */
+  public Path getOutputPath() {
+    return directories.getOutputPath();
+  }
+
+  public Path getInstallBase() {
+    return directories.getInstallBase();
+  }
+
+  /**
+   * Returns the execution root directory associated with this Blaze server
+   * process. This is where all input and output files visible to the actual
+   * build reside.
+   */
+  public Path getExecRoot() {
+    return directories.getExecRoot();
+  }
+
+  /**
+   * Returns path to the cache directory. Path must be inside output base to
+   * ensure that users can run concurrent instances of blaze in different
+   * clients without attempting to concurrently write to the same action cache
+   * on disk, which might not be safe.
+   */
+  Path getCacheDirectory() {
+    return getOutputBase().getChild("action_cache");
+  }
+
+  void recordLastExecutionTime(long commandStartTime) {
+    long currentTimeMillis = runtime.getClock().currentTimeMillis();
+    lastExecutionRange = currentTimeMillis >= commandStartTime
+        ? Range.closed(commandStartTime, currentTimeMillis)
+        : null;
+  }
+
+  /**
+   * Range that represents the last execution time of a build in millis since epoch.
+   */
+  @Nullable
+  public Range<Long> getLastExecutionTimeRange() {
+    return lastExecutionRange;
+  }
+
+  void clearEventBus() {
+    // EventBus does not have an unregister() method, so this is how we release memory associated
+    // with handlers.
+    skyframeExecutor.setEventBus(null);
+  }
+
+  /**
+   * Removes in-memory caches.
+   */
+  public void clearCaches() throws IOException {
+    skyframeExecutor.resetEvaluator();
+    actionCache = null;
+    FileSystemUtils.deleteTree(getCacheDirectory());
+  }
+
+  /**
+   * Returns reference to the lazily instantiated persistent action cache
+   * instance. Note, that method may recreate instance between different build
+   * requests, so return value should not be cached.
+   */
+  public ActionCache getPersistentActionCache(Reporter reporter) throws IOException {
+    if (actionCache == null) {
+      if (OS.getCurrent() == OS.WINDOWS) {
+        // TODO(bazel-team): Add support for a persistent action cache on Windows.
+        actionCache = new NullActionCache();
+        return actionCache;
+      }
+      try (AutoProfiler p = profiledAndLogged("Loading action cache", ProfilerTask.INFO, LOG)) {
+        try {
+          actionCache = new CompactPersistentActionCache(getCacheDirectory(), runtime.getClock());
+        } catch (IOException e) {
+          LOG.log(Level.WARNING, "Failed to load action cache: " + e.getMessage(), e);
+          LoggingUtil.logToRemote(Level.WARNING, "Failed to load action cache: "
+              + e.getMessage(), e);
+          reporter.handle(
+              Event.error("Error during action cache initialization: " + e.getMessage()
+              + ". Corrupted files were renamed to '" + getCacheDirectory() + "/*.bad'. "
+              + "Blaze will now reset action cache data, causing a full rebuild"));
+          actionCache = new CompactPersistentActionCache(getCacheDirectory(), runtime.getClock());
+        }
+      }
+    }
+    return actionCache;
+  }
+
+  /**
+   * Generates a README file in the output base directory. This README file
+   * contains the name of the workspace directory, so that users can figure out
+   * which output base directory corresponds to which workspace.
+   */
+  private void writeOutputBaseReadmeFile() {
+    Preconditions.checkNotNull(getWorkspace());
+    Path outputBaseReadmeFile = getOutputBase().getRelative("README");
+    try {
+      FileSystemUtils.writeIsoLatin1(outputBaseReadmeFile, "WORKSPACE: " + getWorkspace(), "",
+          "The first line of this file is intentionally easy to parse for various",
+          "interactive scripting and debugging purposes.  But please DO NOT write programs",
+          "that exploit it, as they will be broken by design: it is not possible to",
+          "reverse engineer the set of source trees or the --package_path from the output",
+          "tree, and if you attempt it, you will fail, creating subtle and",
+          "hard-to-diagnose bugs, that will no doubt get blamed on changes made by the",
+          "Blaze team.", "", "This directory was generated by Blaze.",
+          "Do not attempt to modify or delete any files in this directory.",
+          "Among other issues, Blaze's file system caching assumes that",
+          "only Blaze will modify this directory and the files in it,",
+          "so if you change anything here you may mess up Blaze's cache.");
+    } catch (IOException e) {
+      LOG.warning("Couldn't write to '" + outputBaseReadmeFile + "': " + e.getMessage());
+    }
+  }
+
+  private void writeDoNotBuildHereFile(Path filePath) {
+    try {
+      FileSystemUtils.createDirectoryAndParents(filePath.getParentDirectory());
+      FileSystemUtils.writeContent(filePath, ISO_8859_1, getWorkspace().toString());
+    } catch (IOException e) {
+      LOG.warning("Couldn't write to '" + filePath + "': " + e.getMessage());
+    }
+  }
+
+  private void writeDoNotBuildHereFile(OptionsProvider startupOptions) {
+    Preconditions.checkNotNull(getWorkspace());
+    writeDoNotBuildHereFile(getOutputBase().getRelative(DO_NOT_BUILD_FILE_NAME));
+    if (startupOptions.getOptions(BlazeServerStartupOptions.class).deepExecRoot) {
+      writeDoNotBuildHereFile(getOutputBase().getRelative("execroot").getRelative(
+          DO_NOT_BUILD_FILE_NAME));
+    }
+  }
+
+  /**
+   * Creates the execRoot dir under outputBase.
+   */
+  private void setupExecRoot() {
+    try {
+      FileSystemUtils.createDirectoryAndParents(directories.getExecRoot());
+    } catch (IOException e) {
+      LOG.warning("failed to create execution root '" + directories.getExecRoot() + "': "
+          + e.getMessage());
+    }
+  }
+}
+
diff --git a/src/main/java/com/google/devtools/build/lib/runtime/CommandEnvironment.java b/src/main/java/com/google/devtools/build/lib/runtime/CommandEnvironment.java
index ee80c85deb..7c05e8ca75 100644
--- a/src/main/java/com/google/devtools/build/lib/runtime/CommandEnvironment.java
+++ b/src/main/java/com/google/devtools/build/lib/runtime/CommandEnvironment.java
@@ -22,6 +22,7 @@ import com.google.common.collect.ImmutableSet;
 import com.google.common.eventbus.EventBus;
 import com.google.devtools.build.lib.actions.PackageRootResolver;
 import com.google.devtools.build.lib.actions.cache.ActionCache;
+import com.google.devtools.build.lib.actions.cache.CompactPersistentActionCache;
 import com.google.devtools.build.lib.analysis.BlazeDirectories;
 import com.google.devtools.build.lib.analysis.BuildView;
 import com.google.devtools.build.lib.analysis.SkyframePackageRootResolver;
@@ -73,6 +74,7 @@ import java.util.concurrent.atomic.AtomicReference;
  */
 public final class CommandEnvironment {
   private final BlazeRuntime runtime;
+  private final BlazeWorkspace workspace;
   private final BlazeDirectories directories;
 
   private final UUID commandId;  // Unique identifier for the command being run
@@ -108,7 +110,8 @@ public final class CommandEnvironment {
 
   public CommandEnvironment(BlazeRuntime runtime, UUID commandId, EventBus eventBus) {
     this.runtime = runtime;
-    this.directories = runtime.getDirectories();
+    this.workspace = runtime.getWorkspace();
+    this.directories = workspace.getDirectories();
     this.commandId = commandId;
     this.reporter = new Reporter();
     this.eventBus = eventBus;
@@ -129,6 +132,10 @@ public final class CommandEnvironment {
     return runtime;
   }
 
+  public BlazeWorkspace getBlazeWorkspace() {
+    return workspace;
+  }
+
   public BlazeDirectories getDirectories() {
     return directories;
   }
@@ -172,7 +179,7 @@ public final class CommandEnvironment {
   }
 
   public PackageManager getPackageManager() {
-    return runtime.getPackageManager();
+    return getSkyframeExecutor().getPackageManager();
   }
 
   public PathFragment getRelativeWorkingDirectory() {
@@ -202,11 +209,11 @@ public final class CommandEnvironment {
   }
 
   public SkyframeExecutor getSkyframeExecutor() {
-    return runtime.getSkyframeExecutor();
+    return workspace.getSkyframeExecutor();
   }
 
   public SkyframeBuildView getSkyframeBuildView() {
-    return runtime.getSkyframeExecutor().getSkyframeBuildView();
+    return getSkyframeExecutor().getSkyframeBuildView();
   }
 
   /**
@@ -286,7 +293,27 @@ public final class CommandEnvironment {
   }
 
   public ActionCache getPersistentActionCache() throws IOException {
-    return runtime.getPersistentActionCache(reporter);
+    return workspace.getPersistentActionCache(reporter);
+  }
+
+  /**
+   * An array of String values useful if Blaze crashes.
+   * For now, just returns the size of the action cache and the build id.
+   */
+  public String[] getCrashData() {
+    return new String[]{
+        getFileSizeString(CompactPersistentActionCache.cacheFile(workspace.getCacheDirectory()),
+                          "action cache"),
+        getCommandId() + " (build id)",
+    };
+  }
+
+  private static String getFileSizeString(Path path, String type) {
+    try {
+      return String.format("%d bytes (%s)", path.getFileSize(), type);
+    } catch (IOException e) {
+      return String.format("unknown file size (%s)", type);
+    }
   }
 
   /**
@@ -314,8 +341,7 @@ public final class CommandEnvironment {
   private boolean loadForConfigurations(EventHandler eventHandler,
       Set<Label> labelsToLoad, boolean keepGoing) throws InterruptedException {
     // Use a new Label Visitor here to avoid erasing the cache on the existing one.
-    TransitivePackageLoader transitivePackageLoader =
-        runtime.getSkyframeExecutor().getPackageManager().newTransitiveLoader();
+    TransitivePackageLoader transitivePackageLoader = getPackageManager().newTransitiveLoader();
     boolean loadingSuccessful = transitivePackageLoader.sync(
         eventHandler, ImmutableSet.<Target>of(),
         labelsToLoad, keepGoing, /*parallelThreads=*/10,
@@ -370,7 +396,7 @@ public final class CommandEnvironment {
   }
 
   public void recordLastExecutionTime() {
-    runtime.recordLastExecutionTime(getCommandStartTime());
+    workspace.recordLastExecutionTime(getCommandStartTime());
   }
 
   public void recordCommandStartTime(long commandStartTime) {
diff --git a/src/main/java/com/google/devtools/build/lib/runtime/commands/CleanCommand.java b/src/main/java/com/google/devtools/build/lib/runtime/commands/CleanCommand.java
index 12630051e6..5ebac2c953 100644
--- a/src/main/java/com/google/devtools/build/lib/runtime/commands/CleanCommand.java
+++ b/src/main/java/com/google/devtools/build/lib/runtime/commands/CleanCommand.java
@@ -20,7 +20,6 @@ import com.google.devtools.build.lib.buildtool.OutputDirectoryLinksUtils;
 import com.google.devtools.build.lib.events.Event;
 import com.google.devtools.build.lib.runtime.BlazeCommand;
 import com.google.devtools.build.lib.runtime.BlazeCommandDispatcher.ShutdownBlazeServerException;
-import com.google.devtools.build.lib.runtime.BlazeRuntime;
 import com.google.devtools.build.lib.runtime.Command;
 import com.google.devtools.build.lib.runtime.CommandEnvironment;
 import com.google.devtools.build.lib.shell.CommandException;
@@ -125,7 +124,6 @@ public final class CleanCommand implements BlazeCommand {
   private void actuallyClean(CommandEnvironment env,
       Path outputBase, Options cleanOptions, String symlinkPrefix) throws IOException,
       ShutdownBlazeServerException, CommandException, ExecException, InterruptedException {
-    BlazeRuntime runtime = env.getRuntime();
     if (env.getOutputService() != null) {
       env.getOutputService().clean();
     }
@@ -162,7 +160,7 @@ public final class CleanCommand implements BlazeCommand {
         .build().execute();
     } else {
       LOG.info("Output cleaning...");
-      runtime.clearCaches();
+      env.getBlazeWorkspace().clearCaches();
       // In order to be sure that we delete everything, delete the workspace directory both for
       // --deep_execroot and for --nodeep_execroot.
       for (String directory : new String[] {
diff --git a/src/main/java/com/google/devtools/build/lib/runtime/commands/DumpCommand.java b/src/main/java/com/google/devtools/build/lib/runtime/commands/DumpCommand.java
index 6acf54658b..b18714e695 100644
--- a/src/main/java/com/google/devtools/build/lib/runtime/commands/DumpCommand.java
+++ b/src/main/java/com/google/devtools/build/lib/runtime/commands/DumpCommand.java
@@ -23,6 +23,7 @@ import com.google.devtools.build.lib.runtime.BlazeCommandUtils;
 import com.google.devtools.build.lib.runtime.BlazeRuntime;
 import com.google.devtools.build.lib.runtime.Command;
 import com.google.devtools.build.lib.runtime.CommandEnvironment;
+import com.google.devtools.build.lib.skyframe.SkyframeExecutor;
 import com.google.devtools.build.lib.util.ExitCode;
 import com.google.devtools.build.lib.vfs.FileSystemUtils;
 import com.google.devtools.common.options.EnumConverter;
@@ -166,7 +167,9 @@ public class DumpCommand implements BlazeCommand {
       }
 
       if (dumpOptions.dumpSkyframe != SkyframeDumpOption.OFF) {
-        success &= dumpSkyframe(runtime, dumpOptions.dumpSkyframe == SkyframeDumpOption.SUMMARY,
+        success &= dumpSkyframe(
+            env.getSkyframeExecutor(),
+            dumpOptions.dumpSkyframe == SkyframeDumpOption.SUMMARY,
             out);
         out.println();
       }
@@ -188,8 +191,8 @@ public class DumpCommand implements BlazeCommand {
     return true;
   }
 
-  private boolean dumpSkyframe(BlazeRuntime runtime, boolean summarize, PrintStream out) {
-    runtime.getSkyframeExecutor().dump(summarize, out);
+  private boolean dumpSkyframe(SkyframeExecutor executor, boolean summarize, PrintStream out) {
+    executor.dump(summarize, out);
     return true;
   }
 
diff --git a/src/main/java/com/google/devtools/build/lib/runtime/commands/InfoCommand.java b/src/main/java/com/google/devtools/build/lib/runtime/commands/InfoCommand.java
index 65d72552f2..f9b217d1d5 100644
--- a/src/main/java/com/google/devtools/build/lib/runtime/commands/InfoCommand.java
+++ b/src/main/java/com/google/devtools/build/lib/runtime/commands/InfoCommand.java
@@ -284,11 +284,11 @@ public class InfoCommand implements BlazeCommand {
       Supplier<BuildConfiguration> configurationSupplier, OptionsProvider options) {
     switch (key) {
       // directories
-      case WORKSPACE : return runtime.getDirectories().getWorkspace();
-      case INSTALL_BASE : return runtime.getDirectories().getInstallBase();
-      case OUTPUT_BASE : return runtime.getDirectories().getOutputBase();
-      case EXECUTION_ROOT : return runtime.getDirectories().getExecRoot();
-      case OUTPUT_PATH : return runtime.getDirectories().getOutputPath();
+      case WORKSPACE : return runtime.getWorkspace().getWorkspace();
+      case INSTALL_BASE : return runtime.getWorkspace().getInstallBase();
+      case OUTPUT_BASE : return runtime.getWorkspace().getOutputBase();
+      case EXECUTION_ROOT : return runtime.getWorkspace().getExecRoot();
+      case OUTPUT_PATH : return runtime.getWorkspace().getOutputPath();
       // These are the only (non-hidden) info items that require a configuration, because the
       // corresponding paths contain the short name. Maybe we should recommend using the symlinks
       // or make them hidden by default?
@@ -298,10 +298,10 @@ public class InfoCommand implements BlazeCommand {
 
       // logs
       case COMMAND_LOG : return BlazeCommandDispatcher.getCommandLogPath(
-          runtime.getDirectories().getOutputBase());
+          runtime.getWorkspace().getOutputBase());
       case MESSAGE_LOG :
         // NB: Duplicated in EventLogModule
-        return runtime.getDirectories().getOutputBase().getRelative("message.log");
+        return runtime.getWorkspace().getOutputBase().getRelative("message.log");
 
       // misc
       case RELEASE : return BlazeVersionInfo.instance().getReleaseName();