diff --git a/src/main/java/com/google/devtools/build/lib/remote/GrpcRemoteCache.java b/src/main/java/com/google/devtools/build/lib/remote/GrpcRemoteCache.java
index 9b7a720..3336316 100644
--- a/src/main/java/com/google/devtools/build/lib/remote/GrpcRemoteCache.java
+++ b/src/main/java/com/google/devtools/build/lib/remote/GrpcRemoteCache.java
@@ -48,6 +48,7 @@
 import com.google.devtools.build.lib.actions.ActionInput;
 import com.google.devtools.build.lib.concurrent.ThreadSafety.ThreadSafe;
 import com.google.devtools.build.lib.remote.RemoteRetrier.ProgressiveBackoff;
+import com.google.devtools.build.lib.remote.common.CacheNotFoundException;
 import com.google.devtools.build.lib.remote.common.SimpleBlobStore.ActionKey;
 import com.google.devtools.build.lib.remote.merkletree.MerkleTree;
 import com.google.devtools.build.lib.remote.options.RemoteOptions;
@@ -250,6 +251,10 @@
     uploader.uploadBlobs(inputsToUpload, /* forceUpload= */ true);
   }
 
+  private static String digestToString(Digest digest) {
+    return digest.getHash() + "/" + digest.getSizeBytes();
+  }
+
   @Override
   protected ListenableFuture<Void> downloadBlob(Digest digest, OutputStream out) {
     if (digest.getSizeBytes() == 0) {
@@ -259,7 +264,7 @@
     if (!options.remoteInstanceName.isEmpty()) {
       resourceName += options.remoteInstanceName + "/";
     }
-    resourceName += "blobs/" + digestUtil.toString(digest);
+    resourceName += "blobs/" + digestToString(digest);
 
     @Nullable Supplier<HashCode> hashSupplier = null;
     if (options.remoteVerifyDownloads) {
@@ -344,7 +349,7 @@
               public void onError(Throwable t) {
                 Status status = Status.fromThrowable(t);
                 if (status.getCode() == Status.Code.NOT_FOUND) {
-                  future.setException(new CacheNotFoundException(digest, digestUtil));
+                  future.setException(new CacheNotFoundException(digest));
                 } else {
                   future.setException(t);
                 }
diff --git a/src/main/java/com/google/devtools/build/lib/remote/RemoteActionInputFetcher.java b/src/main/java/com/google/devtools/build/lib/remote/RemoteActionInputFetcher.java
index 97feb0f..2d82bd6 100644
--- a/src/main/java/com/google/devtools/build/lib/remote/RemoteActionInputFetcher.java
+++ b/src/main/java/com/google/devtools/build/lib/remote/RemoteActionInputFetcher.java
@@ -29,6 +29,7 @@
 import com.google.devtools.build.lib.profiler.Profiler;
 import com.google.devtools.build.lib.profiler.ProfilerTask;
 import com.google.devtools.build.lib.profiler.SilentCloseable;
+import com.google.devtools.build.lib.remote.common.CacheNotFoundException;
 import com.google.devtools.build.lib.remote.util.DigestUtil;
 import com.google.devtools.build.lib.remote.util.Utils;
 import com.google.devtools.build.lib.vfs.Path;
diff --git a/src/main/java/com/google/devtools/build/lib/remote/RemoteModule.java b/src/main/java/com/google/devtools/build/lib/remote/RemoteModule.java
index 24e158a..1598e25 100644
--- a/src/main/java/com/google/devtools/build/lib/remote/RemoteModule.java
+++ b/src/main/java/com/google/devtools/build/lib/remote/RemoteModule.java
@@ -42,6 +42,7 @@
 import com.google.devtools.build.lib.events.Reporter;
 import com.google.devtools.build.lib.exec.ExecutorBuilder;
 import com.google.devtools.build.lib.packages.TargetUtils;
+import com.google.devtools.build.lib.remote.common.CacheNotFoundException;
 import com.google.devtools.build.lib.remote.logging.LoggingInterceptor;
 import com.google.devtools.build.lib.remote.options.RemoteOptions;
 import com.google.devtools.build.lib.remote.options.RemoteOutputsMode;
diff --git a/src/main/java/com/google/devtools/build/lib/remote/RemoteSpawnCache.java b/src/main/java/com/google/devtools/build/lib/remote/RemoteSpawnCache.java
index 4d738d5..52fb136 100644
--- a/src/main/java/com/google/devtools/build/lib/remote/RemoteSpawnCache.java
+++ b/src/main/java/com/google/devtools/build/lib/remote/RemoteSpawnCache.java
@@ -45,6 +45,7 @@
 import com.google.devtools.build.lib.profiler.Profiler;
 import com.google.devtools.build.lib.profiler.ProfilerTask;
 import com.google.devtools.build.lib.profiler.SilentCloseable;
+import com.google.devtools.build.lib.remote.common.CacheNotFoundException;
 import com.google.devtools.build.lib.remote.common.SimpleBlobStore.ActionKey;
 import com.google.devtools.build.lib.remote.merkletree.MerkleTree;
 import com.google.devtools.build.lib.remote.options.RemoteOptions;
diff --git a/src/main/java/com/google/devtools/build/lib/remote/RemoteSpawnRunner.java b/src/main/java/com/google/devtools/build/lib/remote/RemoteSpawnRunner.java
index 181b343..cef0be7 100644
--- a/src/main/java/com/google/devtools/build/lib/remote/RemoteSpawnRunner.java
+++ b/src/main/java/com/google/devtools/build/lib/remote/RemoteSpawnRunner.java
@@ -56,6 +56,7 @@
 import com.google.devtools.build.lib.profiler.Profiler;
 import com.google.devtools.build.lib.profiler.ProfilerTask;
 import com.google.devtools.build.lib.profiler.SilentCloseable;
+import com.google.devtools.build.lib.remote.common.CacheNotFoundException;
 import com.google.devtools.build.lib.remote.common.SimpleBlobStore.ActionKey;
 import com.google.devtools.build.lib.remote.merkletree.MerkleTree;
 import com.google.devtools.build.lib.remote.options.RemoteOptions;
diff --git a/src/main/java/com/google/devtools/build/lib/remote/SimpleBlobStoreActionCache.java b/src/main/java/com/google/devtools/build/lib/remote/SimpleBlobStoreActionCache.java
index 11a2fde..363340c 100644
--- a/src/main/java/com/google/devtools/build/lib/remote/SimpleBlobStoreActionCache.java
+++ b/src/main/java/com/google/devtools/build/lib/remote/SimpleBlobStoreActionCache.java
@@ -34,8 +34,6 @@
 import com.google.devtools.build.lib.remote.util.Utils;
 import com.google.devtools.build.lib.vfs.Path;
 import com.google.protobuf.ByteString;
-import com.google.protobuf.InvalidProtocolBufferException;
-import java.io.ByteArrayOutputStream;
 import java.io.IOException;
 import java.io.OutputStream;
 import javax.annotation.Nullable;
@@ -89,30 +87,12 @@
   @Override
   public ActionResult getCachedActionResult(ActionKey actionKey)
       throws IOException, InterruptedException {
-    try {
-      byte[] data = downloadActionResult(actionKey.getDigest());
-      return ActionResult.parseFrom(data);
-    } catch (InvalidProtocolBufferException | CacheNotFoundException e) {
-      return null;
-    }
-  }
-
-  private byte[] downloadActionResult(Digest digest) throws IOException, InterruptedException {
-    if (digest.getSizeBytes() == 0) {
-      return new byte[0];
-    }
-    // This unconditionally downloads the whole blob into memory!
-    ByteArrayOutputStream out = new ByteArrayOutputStream();
-    boolean success = getFromFuture(blobStore.getActionResult(digest.getHash(), out));
-    if (!success) {
-      throw new CacheNotFoundException(digest, digestUtil);
-    }
-    return out.toByteArray();
+    return Utils.getFromFuture(blobStore.downloadActionResult(actionKey));
   }
 
   public void setCachedActionResult(ActionKey actionKey, ActionResult result)
       throws IOException, InterruptedException {
-    blobStore.putActionResult(actionKey, result);
+    blobStore.uploadActionResult(actionKey, result);
   }
 
   @Override
@@ -127,22 +107,18 @@
     HashingOutputStream hashOut =
         options.remoteVerifyDownloads ? digestUtil.newHashingOutputStream(out) : null;
     Futures.addCallback(
-        blobStore.get(digest.getHash(), hashOut != null ? hashOut : out),
-        new FutureCallback<Boolean>() {
+        blobStore.downloadBlob(digest, hashOut != null ? hashOut : out),
+        new FutureCallback<Void>() {
           @Override
-          public void onSuccess(Boolean found) {
-            if (found) {
-              try {
-                if (hashOut != null) {
-                  verifyContents(digest.getHash(), DigestUtil.hashCodeToString(hashOut.hash()));
-                }
-                out.flush();
-                outerF.set(null);
-              } catch (IOException e) {
-                outerF.setException(e);
+          public void onSuccess(Void unused) {
+            try {
+              if (hashOut != null) {
+                verifyContents(digest.getHash(), DigestUtil.hashCodeToString(hashOut.hash()));
               }
-            } else {
-              outerF.setException(new CacheNotFoundException(digest, digestUtil));
+              out.flush();
+              outerF.set(null);
+            } catch (IOException e) {
+              outerF.setException(e);
             }
           }
 
diff --git a/src/main/java/com/google/devtools/build/lib/remote/CacheNotFoundException.java b/src/main/java/com/google/devtools/build/lib/remote/common/CacheNotFoundException.java
similarity index 72%
rename from src/main/java/com/google/devtools/build/lib/remote/CacheNotFoundException.java
rename to src/main/java/com/google/devtools/build/lib/remote/common/CacheNotFoundException.java
index 03a0fee..cad87a1 100644
--- a/src/main/java/com/google/devtools/build/lib/remote/CacheNotFoundException.java
+++ b/src/main/java/com/google/devtools/build/lib/remote/common/CacheNotFoundException.java
@@ -12,21 +12,20 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package com.google.devtools.build.lib.remote;
+package com.google.devtools.build.lib.remote.common;
 
 import build.bazel.remote.execution.v2.Digest;
-import com.google.devtools.build.lib.remote.util.DigestUtil;
 import java.io.IOException;
 
 /**
- * An exception to indicate cache misses.
- * TODO(olaola): have a class of checked RemoteCacheExceptions.
+ * An exception to indicate cache misses. TODO(olaola): have a class of checked
+ * RemoteCacheExceptions.
  */
 public final class CacheNotFoundException extends IOException {
   private final Digest missingDigest;
 
-  CacheNotFoundException(Digest missingDigest, DigestUtil digestUtil) {
-    super("Missing digest: " + digestUtil.toString(missingDigest));
+  public CacheNotFoundException(Digest missingDigest) {
+    super("Missing digest: " + missingDigest.getHash() + "/" + missingDigest.getSizeBytes());
     this.missingDigest = missingDigest;
   }
 
diff --git a/src/main/java/com/google/devtools/build/lib/remote/common/SimpleBlobStore.java b/src/main/java/com/google/devtools/build/lib/remote/common/SimpleBlobStore.java
index 92af8c7..da6e6de 100644
--- a/src/main/java/com/google/devtools/build/lib/remote/common/SimpleBlobStore.java
+++ b/src/main/java/com/google/devtools/build/lib/remote/common/SimpleBlobStore.java
@@ -14,8 +14,10 @@
 
 package com.google.devtools.build.lib.remote.common;
 
+import build.bazel.remote.execution.v2.Action;
 import build.bazel.remote.execution.v2.ActionResult;
 import build.bazel.remote.execution.v2.Digest;
+import com.google.common.base.Preconditions;
 import com.google.common.util.concurrent.ListenableFuture;
 import com.google.devtools.build.lib.vfs.Path;
 import com.google.protobuf.ByteString;
@@ -23,15 +25,15 @@
 import java.io.OutputStream;
 
 /**
- * An interface for storing BLOBs each one indexed by a string (hash in hexadecimal).
+ * An interface for a remote caching protocol.
  *
  * <p>Implementations must be thread-safe.
  */
 public interface SimpleBlobStore {
 
   /**
-   * A special type of Digest that is used only as a remote action cache key. This is a separate
-   * type in order to prevent accidentally using other Digests as action keys.
+   * A key in the remote action cache. The type wraps around a {@link Digest} of an {@link Action}.
+   * Action keys are special in that they aren't content-addressable but refer to action results.
    */
   final class ActionKey {
     private final Digest digest;
@@ -41,49 +43,58 @@
     }
 
     public ActionKey(Digest digest) {
-      this.digest = digest;
+      this.digest = Preconditions.checkNotNull(digest, "digest");
     }
   }
 
   /**
-   * Fetches the BLOB associated with the {@code key} from the CAS and writes it to {@code out}.
+   * Downloads an action result for the {@code actionKey}.
    *
-   * <p>The caller is responsible to close {@code out}.
-   *
-   * @return {@code true} if the {@code key} was found. {@code false} otherwise.
+   * @param actionKey The digest of the {@link Action} that generated the action result.
+   * @return A Future representing pending download of an action result. If an action result for
+   *     {@code actionKey} cannot be found the result of the Future is {@code null}.
    */
-  ListenableFuture<Boolean> get(String key, OutputStream out);
+  ListenableFuture<ActionResult> downloadActionResult(ActionKey actionKey);
 
   /**
-   * Fetches the BLOB associated with the {@code key} from the Action Cache and writes it to {@code
-   * out}.
+   * Uploads an action result for the {@code actionKey}.
    *
-   * <p>The caller is responsible to close {@code out}.
-   *
-   * @return {@code true} if the {@code key} was found. {@code false} otherwise.
+   * @param actionKey The digest of the {@link Action} that generated the action result.
+   * @param actionResult The action result to associate with the {@code actionKey}.
+   * @throws IOException If there is an error uploading the action result.
+   * @throws InterruptedException In case the thread
    */
-  ListenableFuture<Boolean> getActionResult(String actionKey, OutputStream out);
-
-  /** Uploads an {@link ActionResult} keyed by the action hash to the action cache. */
-  void putActionResult(ActionKey actionDigest, ActionResult actionResult)
+  void uploadActionResult(ActionKey actionKey, ActionResult actionResult)
       throws IOException, InterruptedException;
 
-  /** Close resources associated with the blob store. */
-  void close();
+  /**
+   * Downloads a BLOB for the given {@code digest} and writes it to {@code out}.
+   *
+   * <p>It's the callers responsibility to close {@code out}.
+   *
+   * @return A Future representing pending completion of the download. If a BLOB for {@code digest}
+   *     does not exist in the cache the Future fails with a {@link CacheNotFoundException}.
+   */
+  ListenableFuture<Void> downloadBlob(Digest digest, OutputStream out);
 
   /**
-   * Uploads a file.
+   * Uploads a {@code file} to the CAS.
    *
-   * @param digest the digest of the file.
-   * @param file the file to upload.
+   * @param digest The digest of the file.
+   * @param file The file to upload.
+   * @return A future representing pending completion of the upload.
    */
   ListenableFuture<Void> uploadFile(Digest digest, Path file);
 
   /**
-   * Uploads a BLOB.
+   * Uploads a BLOB to the CAS.
    *
-   * @param digest the digest of the blob.
-   * @param data the blob to upload.
+   * @param digest The digest of the blob.
+   * @param data The BLOB to upload.
+   * @return A future representing pending completion of the upload.
    */
   ListenableFuture<Void> uploadBlob(Digest digest, ByteString data);
+
+  /** Close resources associated with the remote cache. */
+  void close();
 }
diff --git a/src/main/java/com/google/devtools/build/lib/remote/disk/CombinedDiskHttpBlobStore.java b/src/main/java/com/google/devtools/build/lib/remote/disk/CombinedDiskHttpBlobStore.java
index c9377e4..2f38e3a 100644
--- a/src/main/java/com/google/devtools/build/lib/remote/disk/CombinedDiskHttpBlobStore.java
+++ b/src/main/java/com/google/devtools/build/lib/remote/disk/CombinedDiskHttpBlobStore.java
@@ -26,8 +26,6 @@
 import java.io.OutputStream;
 import java.util.UUID;
 import java.util.concurrent.ExecutionException;
-import java.util.logging.Level;
-import java.util.logging.Logger;
 
 /**
  * A {@link SimpleBlobStore} implementation combining two blob stores. A local disk blob store and a
@@ -35,7 +33,6 @@
  * blob added to the first. Put puts the blob on both stores.
  */
 public final class CombinedDiskHttpBlobStore implements SimpleBlobStore {
-  private static final Logger logger = Logger.getLogger(CombinedDiskHttpBlobStore.class.getName());
 
   private final SimpleBlobStore remoteCache;
   private final OnDiskBlobStore diskCache;
@@ -46,10 +43,10 @@
   }
 
   @Override
-  public void putActionResult(ActionKey actionKey, ActionResult actionResult)
+  public void uploadActionResult(ActionKey actionKey, ActionResult actionResult)
       throws IOException, InterruptedException {
-    diskCache.putActionResult(actionKey, actionResult);
-    remoteCache.putActionResult(actionKey, actionResult);
+    diskCache.uploadActionResult(actionKey, actionResult);
+    remoteCache.uploadActionResult(actionKey, actionResult);
   }
 
   @Override
@@ -84,77 +81,74 @@
     return Futures.immediateFuture(null);
   }
 
-  @Override
-  public ListenableFuture<Boolean> get(String key, OutputStream out) {
-    return get(key, out, /* actionResult= */ false);
+  private Path newTempPath() {
+    return diskCache.toPath(UUID.randomUUID().toString(), /* actionResult= */ false);
   }
 
-  private ListenableFuture<Boolean> get(String key, OutputStream out, boolean actionResult) {
-    boolean foundOnDisk =
-        actionResult ? diskCache.containsActionResult(key) : diskCache.contains(key);
+  private static ListenableFuture<Void> closeStreamOnError(
+      ListenableFuture<Void> f, OutputStream out) {
+    return Futures.catchingAsync(
+        f,
+        Exception.class,
+        (rootCause) -> {
+          try {
+            out.close();
+          } catch (IOException e) {
+            rootCause.addSuppressed(e);
+          }
+          return Futures.immediateFailedFuture(rootCause);
+        },
+        MoreExecutors.directExecutor());
+  }
 
-    if (foundOnDisk) {
-      return getFromCache(diskCache, key, out, actionResult);
-    } else {
-      return getFromRemoteAndSaveToDisk(key, out, actionResult);
+  @Override
+  public ListenableFuture<Void> downloadBlob(Digest digest, OutputStream out) {
+    if (diskCache.contains(digest)) {
+      return diskCache.downloadBlob(digest, out);
     }
-  }
 
-  @Override
-  public ListenableFuture<Boolean> getActionResult(String key, OutputStream out) {
-    return get(key, out, /* actionResult= */ true);
-  }
-
-  private ListenableFuture<Boolean> getFromRemoteAndSaveToDisk(
-      String key, OutputStream out, boolean actionResult) {
-    // Write a temporary file first, and then rename, to avoid data corruption in case of a crash.
-    Path temp = diskCache.toPath(UUID.randomUUID().toString(), /* actionResult= */ false);
-
-    OutputStream tempOut;
+    Path tempPath = newTempPath();
+    final OutputStream tempOut;
     try {
-      tempOut = temp.getOutputStream();
+      tempOut = tempPath.getOutputStream();
     } catch (IOException e) {
       return Futures.immediateFailedFuture(e);
     }
-    ListenableFuture<Boolean> chained =
+
+    ListenableFuture<Void> download =
+        closeStreamOnError(remoteCache.downloadBlob(digest, tempOut), tempOut);
+    ListenableFuture<Void> saveToDiskAndTarget =
         Futures.transformAsync(
-            getFromCache(remoteCache, key, tempOut, actionResult),
-            (found) -> {
-              if (!found) {
-                return Futures.immediateFuture(false);
-              } else {
-                saveToDiskCache(key, temp, actionResult);
-                return getFromCache(diskCache, key, out, actionResult);
+            download,
+            (unused) -> {
+              try {
+                tempOut.close();
+                diskCache.captureFile(tempPath, digest, /* isActionCache= */ false);
+              } catch (IOException e) {
+                return Futures.immediateFailedFuture(e);
               }
+              return diskCache.downloadBlob(digest, out);
             },
             MoreExecutors.directExecutor());
-    chained.addListener(
-        () -> {
-          try {
-            tempOut.close();
-          } catch (IOException e) {
-            // not sure what to do here, we either are here because of another exception being
-            // thrown, or we have successfully used the file we are trying (and failing) to close
-            logger.log(Level.WARNING, "Failed to close temporary file on get", e);
+    return saveToDiskAndTarget;
+  }
+
+  @Override
+  public ListenableFuture<ActionResult> downloadActionResult(ActionKey actionKey) {
+    if (diskCache.containsActionResult(actionKey)) {
+      return diskCache.downloadActionResult(actionKey);
+    }
+
+    return Futures.transformAsync(
+        remoteCache.downloadActionResult(actionKey),
+        (actionResult) -> {
+          if (actionResult == null) {
+            return Futures.immediateFuture(null);
+          } else {
+            diskCache.uploadActionResult(actionKey, actionResult);
+            return Futures.immediateFuture(actionResult);
           }
         },
         MoreExecutors.directExecutor());
-    return chained;
-  }
-
-  private void saveToDiskCache(String key, Path temp, boolean actionResult) throws IOException {
-    Path target = diskCache.toPath(key, actionResult);
-    // TODO(ulfjack): Fsync temp here before we rename it to avoid data loss in the
-    // case of machine crashes (the OS may reorder the writes and the rename).
-    temp.renameTo(target);
-  }
-
-  private ListenableFuture<Boolean> getFromCache(
-      SimpleBlobStore blobStore, String key, OutputStream tempOut, boolean actionResult) {
-    if (!actionResult) {
-      return blobStore.get(key, tempOut);
-    } else {
-      return blobStore.getActionResult(key, tempOut);
-    }
   }
 }
diff --git a/src/main/java/com/google/devtools/build/lib/remote/disk/OnDiskBlobStore.java b/src/main/java/com/google/devtools/build/lib/remote/disk/OnDiskBlobStore.java
index 205dd9f..ddd0cec 100644
--- a/src/main/java/com/google/devtools/build/lib/remote/disk/OnDiskBlobStore.java
+++ b/src/main/java/com/google/devtools/build/lib/remote/disk/OnDiskBlobStore.java
@@ -18,8 +18,9 @@
 import com.google.common.io.ByteStreams;
 import com.google.common.util.concurrent.Futures;
 import com.google.common.util.concurrent.ListenableFuture;
-import com.google.common.util.concurrent.SettableFuture;
+import com.google.devtools.build.lib.remote.common.CacheNotFoundException;
 import com.google.devtools.build.lib.remote.common.SimpleBlobStore;
+import com.google.devtools.build.lib.remote.util.Utils;
 import com.google.devtools.build.lib.vfs.Path;
 import com.google.protobuf.ByteString;
 import java.io.IOException;
@@ -37,39 +38,48 @@
   }
 
   /** Returns {@code true} if the provided {@code key} is stored in the CAS. */
-  public boolean contains(String key) {
-    return toPath(key, /* actionResult= */ false).exists();
+  public boolean contains(Digest digest) {
+    return toPath(digest.getHash(), /* actionResult= */ false).exists();
   }
 
   /** Returns {@code true} if the provided {@code key} is stored in the Action Cache. */
-  public boolean containsActionResult(String key) {
-    return toPath(key, /* actionResult= */ true).exists();
+  public boolean containsActionResult(ActionKey actionKey) {
+    return toPath(actionKey.getDigest().getHash(), /* actionResult= */ true).exists();
   }
 
-  @Override
-  public ListenableFuture<Boolean> get(String key, OutputStream out) {
-    SettableFuture<Boolean> f = SettableFuture.create();
-    Path p = toPath(key, /* actionResult= */ false);
+  public void captureFile(Path src, Digest digest, boolean isActionCache) throws IOException {
+    Path target = toPath(digest.getHash(), isActionCache);
+    src.renameTo(target);
+  }
+
+  private ListenableFuture<Void> download(Digest digest, OutputStream out, boolean isActionCache) {
+    Path p = toPath(digest.getHash(), isActionCache);
     if (!p.exists()) {
-      f.set(false);
+      return Futures.immediateFailedFuture(new CacheNotFoundException(digest));
     } else {
       try (InputStream in = p.getInputStream()) {
         ByteStreams.copy(in, out);
-        f.set(true);
+        return Futures.immediateFuture(null);
       } catch (IOException e) {
-        f.setException(e);
+        return Futures.immediateFailedFuture(e);
       }
     }
-    return f;
   }
 
   @Override
-  public ListenableFuture<Boolean> getActionResult(String key, OutputStream out) {
-    return get(getDiskKey(key, /* actionResult= */ true), out);
+  public ListenableFuture<Void> downloadBlob(Digest digest, OutputStream out) {
+    return download(digest, out, /* isActionCache= */ false);
   }
 
   @Override
-  public void putActionResult(ActionKey actionKey, ActionResult actionResult) throws IOException {
+  public ListenableFuture<ActionResult> downloadActionResult(ActionKey actionKey) {
+    return Utils.downloadAsActionResult(
+        actionKey, (digest, out) -> download(digest, out, /* isActionCache= */ true));
+  }
+
+  @Override
+  public void uploadActionResult(ActionKey actionKey, ActionResult actionResult)
+      throws IOException {
     try (InputStream data = actionResult.toByteString().newInput()) {
       saveFile(getDiskKey(actionKey.getDigest().getHash(), /* actionResult= */ true), data);
     }
diff --git a/src/main/java/com/google/devtools/build/lib/remote/http/DownloadCommand.java b/src/main/java/com/google/devtools/build/lib/remote/http/DownloadCommand.java
index 4ef3b21..643c45d 100644
--- a/src/main/java/com/google/devtools/build/lib/remote/http/DownloadCommand.java
+++ b/src/main/java/com/google/devtools/build/lib/remote/http/DownloadCommand.java
@@ -13,6 +13,7 @@
 // limitations under the License.
 package com.google.devtools.build.lib.remote.http;
 
+import build.bazel.remote.execution.v2.Digest;
 import com.google.common.base.Preconditions;
 import java.io.OutputStream;
 import java.net.URI;
@@ -22,13 +23,13 @@
 
   private final URI uri;
   private final boolean casDownload;
-  private final String hash;
+  private final Digest digest;
   private final OutputStream out;
 
-  protected DownloadCommand(URI uri, boolean casDownload, String hash, OutputStream out) {
+  protected DownloadCommand(URI uri, boolean casDownload, Digest digest, OutputStream out) {
     this.uri = Preconditions.checkNotNull(uri);
     this.casDownload = casDownload;
-    this.hash = Preconditions.checkNotNull(hash);
+    this.digest = Preconditions.checkNotNull(digest);
     this.out = Preconditions.checkNotNull(out);
   }
 
@@ -40,8 +41,8 @@
     return casDownload;
   }
 
-  public String hash() {
-    return hash;
+  public Digest digest() {
+    return digest;
   }
 
   public OutputStream out() {
diff --git a/src/main/java/com/google/devtools/build/lib/remote/http/HttpBlobStore.java b/src/main/java/com/google/devtools/build/lib/remote/http/HttpBlobStore.java
index 8065a62..19e9bd9 100644
--- a/src/main/java/com/google/devtools/build/lib/remote/http/HttpBlobStore.java
+++ b/src/main/java/com/google/devtools/build/lib/remote/http/HttpBlobStore.java
@@ -20,7 +20,9 @@
 import com.google.common.util.concurrent.Futures;
 import com.google.common.util.concurrent.ListenableFuture;
 import com.google.common.util.concurrent.SettableFuture;
+import com.google.devtools.build.lib.remote.common.CacheNotFoundException;
 import com.google.devtools.build.lib.remote.common.SimpleBlobStore;
+import com.google.devtools.build.lib.remote.util.Utils;
 import com.google.devtools.build.lib.vfs.Path;
 import com.google.protobuf.ByteString;
 import io.netty.bootstrap.Bootstrap;
@@ -416,12 +418,12 @@
   }
 
   @Override
-  public ListenableFuture<Boolean> get(String key, OutputStream out) {
-    return get(key, out, true);
+  public ListenableFuture<Void> downloadBlob(Digest digest, OutputStream out) {
+    return get(digest, out, /* casDownload= */ true);
   }
 
   @SuppressWarnings("FutureReturnValueIgnored")
-  private ListenableFuture<Boolean> get(String key, final OutputStream out, boolean casDownload) {
+  private ListenableFuture<Void> get(Digest digest, final OutputStream out, boolean casDownload) {
     final AtomicBoolean dataWritten = new AtomicBoolean();
     OutputStream wrappedOut =
         new OutputStream() {
@@ -446,8 +448,8 @@
             out.flush();
           }
         };
-    DownloadCommand download = new DownloadCommand(uri, casDownload, key, wrappedOut);
-    SettableFuture<Boolean> outerF = SettableFuture.create();
+    DownloadCommand downloadCmd = new DownloadCommand(uri, casDownload, digest, wrappedOut);
+    SettableFuture<Void> outerF = SettableFuture.create();
     acquireDownloadChannel()
         .addListener(
             (Future<Channel> chP) -> {
@@ -457,12 +459,12 @@
               }
 
               Channel ch = chP.getNow();
-              ch.writeAndFlush(download)
+              ch.writeAndFlush(downloadCmd)
                   .addListener(
                       (f) -> {
                         try {
                           if (f.isSuccess()) {
-                            outerF.set(true);
+                            outerF.set(null);
                           } else {
                             Throwable cause = f.cause();
                             // cause can be of type HttpException, because Netty uses
@@ -475,10 +477,10 @@
                                 // The error is due to an auth token having expired. Let's try
                                 // again.
                                 refreshCredentials();
-                                getAfterCredentialRefresh(download, outerF);
+                                getAfterCredentialRefresh(downloadCmd, outerF);
                                 return;
                               } else if (cacheMiss(response.status())) {
-                                outerF.set(false);
+                                outerF.setException(new CacheNotFoundException(digest));
                                 return;
                               }
                             }
@@ -493,7 +495,7 @@
   }
 
   @SuppressWarnings("FutureReturnValueIgnored")
-  private void getAfterCredentialRefresh(DownloadCommand cmd, SettableFuture<Boolean> outerF) {
+  private void getAfterCredentialRefresh(DownloadCommand cmd, SettableFuture<Void> outerF) {
     acquireDownloadChannel()
         .addListener(
             (Future<Channel> chP) -> {
@@ -508,13 +510,13 @@
                       (f) -> {
                         try {
                           if (f.isSuccess()) {
-                            outerF.set(true);
+                            outerF.set(null);
                           } else {
                             Throwable cause = f.cause();
                             if (cause instanceof HttpException) {
                               HttpResponse response = ((HttpException) cause).response();
                               if (cacheMiss(response.status())) {
-                                outerF.set(false);
+                                outerF.setException(new CacheNotFoundException(cmd.digest()));
                                 return;
                               }
                             }
@@ -528,8 +530,9 @@
   }
 
   @Override
-  public ListenableFuture<Boolean> getActionResult(String actionKey, OutputStream out) {
-    return get(actionKey, out, false);
+  public ListenableFuture<ActionResult> downloadActionResult(ActionKey actionKey) {
+    return Utils.downloadAsActionResult(
+        actionKey, (digest, out) -> get(digest, out, /* casDownload= */ false));
   }
 
   @SuppressWarnings("FutureReturnValueIgnored")
@@ -633,7 +636,7 @@
   }
 
   @Override
-  public void putActionResult(ActionKey actionKey, ActionResult actionResult)
+  public void uploadActionResult(ActionKey actionKey, ActionResult actionResult)
       throws IOException, InterruptedException {
     ByteString serialized = actionResult.toByteString();
     try (InputStream in = serialized.newInput()) {
diff --git a/src/main/java/com/google/devtools/build/lib/remote/http/HttpDownloadHandler.java b/src/main/java/com/google/devtools/build/lib/remote/http/HttpDownloadHandler.java
index 3359820..2ba92ec 100644
--- a/src/main/java/com/google/devtools/build/lib/remote/http/HttpDownloadHandler.java
+++ b/src/main/java/com/google/devtools/build/lib/remote/http/HttpDownloadHandler.java
@@ -136,7 +136,7 @@
     }
     DownloadCommand cmd = (DownloadCommand) msg;
     out = cmd.out();
-    path = constructPath(cmd.uri(), cmd.hash(), cmd.casDownload());
+    path = constructPath(cmd.uri(), cmd.digest().getHash(), cmd.casDownload());
     HttpRequest request = buildRequest(path, constructHost(cmd.uri()));
     addCredentialHeaders(request, cmd.uri());
     addExtraRemoteHeaders(request);
diff --git a/src/main/java/com/google/devtools/build/lib/remote/util/DigestUtil.java b/src/main/java/com/google/devtools/build/lib/remote/util/DigestUtil.java
index b17770c..6fc1446 100644
--- a/src/main/java/com/google/devtools/build/lib/remote/util/DigestUtil.java
+++ b/src/main/java/com/google/devtools/build/lib/remote/util/DigestUtil.java
@@ -116,7 +116,7 @@
     return new HashingOutputStream(hashFn.getHashFunction(), out);
   }
 
-  public String toString(Digest digest) {
+  public static String toString(Digest digest) {
     return digest.getHash() + "/" + digest.getSizeBytes();
   }
 
diff --git a/src/main/java/com/google/devtools/build/lib/remote/util/Utils.java b/src/main/java/com/google/devtools/build/lib/remote/util/Utils.java
index 4d824e0..f1c3083 100644
--- a/src/main/java/com/google/devtools/build/lib/remote/util/Utils.java
+++ b/src/main/java/com/google/devtools/build/lib/remote/util/Utils.java
@@ -13,20 +13,31 @@
 // limitations under the License.
 package com.google.devtools.build.lib.remote.util;
 
+import build.bazel.remote.execution.v2.ActionResult;
+import build.bazel.remote.execution.v2.Digest;
 import com.google.common.collect.ImmutableSet;
+import com.google.common.util.concurrent.FluentFuture;
+import com.google.common.util.concurrent.Futures;
 import com.google.common.util.concurrent.ListenableFuture;
+import com.google.common.util.concurrent.MoreExecutors;
 import com.google.devtools.build.lib.actions.ActionInput;
 import com.google.devtools.build.lib.actions.ExecutionRequirements;
 import com.google.devtools.build.lib.actions.Spawn;
 import com.google.devtools.build.lib.actions.SpawnResult;
 import com.google.devtools.build.lib.actions.SpawnResult.Status;
+import com.google.devtools.build.lib.remote.common.CacheNotFoundException;
+import com.google.devtools.build.lib.remote.common.SimpleBlobStore.ActionKey;
 import com.google.devtools.build.lib.remote.options.RemoteOutputsMode;
 import com.google.devtools.build.lib.vfs.PathFragment;
 import com.google.protobuf.ByteString;
+import com.google.protobuf.InvalidProtocolBufferException;
+import java.io.ByteArrayOutputStream;
 import java.io.IOException;
+import java.io.OutputStream;
 import java.util.Collection;
 import java.util.Collections;
 import java.util.concurrent.ExecutionException;
+import java.util.function.BiFunction;
 import javax.annotation.Nullable;
 
 /** Utility methods for the remote package. * */
@@ -119,6 +130,25 @@
     return e.getMessage();
   }
 
+  @SuppressWarnings("ProtoParseWithRegistry")
+  public static ListenableFuture<ActionResult> downloadAsActionResult(
+      ActionKey actionDigest,
+      BiFunction<Digest, OutputStream, ListenableFuture<Void>> downloadFunction) {
+    ByteArrayOutputStream data = new ByteArrayOutputStream(/* size= */ 1024);
+    ListenableFuture<Void> download = downloadFunction.apply(actionDigest.getDigest(), data);
+    return FluentFuture.from(download)
+        .transformAsync(
+            (v) -> {
+              try {
+                return Futures.immediateFuture(ActionResult.parseFrom(data.toByteArray()));
+              } catch (InvalidProtocolBufferException e) {
+                return Futures.immediateFailedFuture(e);
+              }
+            },
+            MoreExecutors.directExecutor())
+        .catching(CacheNotFoundException.class, (e) -> null, MoreExecutors.directExecutor());
+  }
+
   /** An in-memory output file. */
   public static final class InMemoryOutput {
     private final ActionInput output;
diff --git a/src/test/java/com/google/devtools/build/lib/remote/AbstractRemoteActionCacheTests.java b/src/test/java/com/google/devtools/build/lib/remote/AbstractRemoteActionCacheTests.java
index d8bc54a..af3e4f6 100644
--- a/src/test/java/com/google/devtools/build/lib/remote/AbstractRemoteActionCacheTests.java
+++ b/src/test/java/com/google/devtools/build/lib/remote/AbstractRemoteActionCacheTests.java
@@ -54,6 +54,7 @@
 import com.google.devtools.build.lib.clock.JavaClock;
 import com.google.devtools.build.lib.remote.AbstractRemoteActionCache.OutputFilesLocker;
 import com.google.devtools.build.lib.remote.AbstractRemoteActionCache.UploadManifest;
+import com.google.devtools.build.lib.remote.common.CacheNotFoundException;
 import com.google.devtools.build.lib.remote.common.SimpleBlobStore.ActionKey;
 import com.google.devtools.build.lib.remote.options.RemoteOptions;
 import com.google.devtools.build.lib.remote.util.DigestUtil;
@@ -1237,7 +1238,7 @@
       Futures.addCallback(
           downloadResult != null
               ? downloadResult
-              : Futures.immediateFailedFuture(new CacheNotFoundException(digest, digestUtil)),
+              : Futures.immediateFailedFuture(new CacheNotFoundException(digest)),
           new FutureCallback<byte[]>() {
             @Override
             public void onSuccess(byte[] bytes) {
diff --git a/src/test/java/com/google/devtools/build/lib/remote/RemoteActionInputFetcherTest.java b/src/test/java/com/google/devtools/build/lib/remote/RemoteActionInputFetcherTest.java
index ddf5306..0615c92 100644
--- a/src/test/java/com/google/devtools/build/lib/remote/RemoteActionInputFetcherTest.java
+++ b/src/test/java/com/google/devtools/build/lib/remote/RemoteActionInputFetcherTest.java
@@ -33,6 +33,7 @@
 import com.google.devtools.build.lib.actions.cache.VirtualActionInput;
 import com.google.devtools.build.lib.actions.util.ActionsTestUtil;
 import com.google.devtools.build.lib.clock.JavaClock;
+import com.google.devtools.build.lib.remote.common.CacheNotFoundException;
 import com.google.devtools.build.lib.remote.common.SimpleBlobStore.ActionKey;
 import com.google.devtools.build.lib.remote.options.RemoteOptions;
 import com.google.devtools.build.lib.remote.util.DigestUtil;
@@ -252,7 +253,7 @@
     protected ListenableFuture<Void> downloadBlob(Digest digest, OutputStream out) {
       ByteString data = cacheEntries.get(digest);
       if (data == null) {
-        return Futures.immediateFailedFuture(new CacheNotFoundException(digest, digestUtil));
+        return Futures.immediateFailedFuture(new CacheNotFoundException(digest));
       }
       try {
         data.writeTo(out);
diff --git a/src/test/java/com/google/devtools/build/lib/remote/RemoteSpawnCacheTest.java b/src/test/java/com/google/devtools/build/lib/remote/RemoteSpawnCacheTest.java
index 73eec07..083491b 100644
--- a/src/test/java/com/google/devtools/build/lib/remote/RemoteSpawnCacheTest.java
+++ b/src/test/java/com/google/devtools/build/lib/remote/RemoteSpawnCacheTest.java
@@ -57,6 +57,7 @@
 import com.google.devtools.build.lib.exec.SpawnRunner.ProgressStatus;
 import com.google.devtools.build.lib.exec.SpawnRunner.SpawnExecutionContext;
 import com.google.devtools.build.lib.exec.util.FakeOwner;
+import com.google.devtools.build.lib.remote.common.CacheNotFoundException;
 import com.google.devtools.build.lib.remote.common.SimpleBlobStore.ActionKey;
 import com.google.devtools.build.lib.remote.options.RemoteOptions;
 import com.google.devtools.build.lib.remote.options.RemoteOutputsMode;
@@ -595,7 +596,7 @@
                 return actionResult;
               }
             });
-    doThrow(new CacheNotFoundException(digest, digestUtil))
+    doThrow(new CacheNotFoundException(digest))
         .when(remoteCache)
         .download(eq(actionResult), eq(execRoot), eq(outErr), any());
 
diff --git a/src/test/java/com/google/devtools/build/lib/remote/RemoteSpawnRunnerTest.java b/src/test/java/com/google/devtools/build/lib/remote/RemoteSpawnRunnerTest.java
index cf52c57..b1b9cff 100644
--- a/src/test/java/com/google/devtools/build/lib/remote/RemoteSpawnRunnerTest.java
+++ b/src/test/java/com/google/devtools/build/lib/remote/RemoteSpawnRunnerTest.java
@@ -63,6 +63,7 @@
 import com.google.devtools.build.lib.exec.SpawnRunner;
 import com.google.devtools.build.lib.exec.SpawnRunner.SpawnExecutionContext;
 import com.google.devtools.build.lib.exec.util.FakeOwner;
+import com.google.devtools.build.lib.remote.common.CacheNotFoundException;
 import com.google.devtools.build.lib.remote.common.SimpleBlobStore.ActionKey;
 import com.google.devtools.build.lib.remote.options.RemoteOptions;
 import com.google.devtools.build.lib.remote.options.RemoteOutputsMode;
@@ -594,7 +595,7 @@
 
     ActionResult cachedResult = ActionResult.newBuilder().setExitCode(0).build();
     when(cache.getCachedActionResult(any(ActionKey.class))).thenReturn(cachedResult);
-    Exception downloadFailure = new CacheNotFoundException(Digest.getDefaultInstance(), digestUtil);
+    Exception downloadFailure = new CacheNotFoundException(Digest.getDefaultInstance());
     doThrow(downloadFailure)
         .when(cache)
         .download(eq(cachedResult), any(Path.class), any(FileOutErr.class), any());
@@ -631,7 +632,7 @@
     when(executor.executeRemotely(any(ExecuteRequest.class)))
         .thenReturn(cachedResponse)
         .thenReturn(executedResponse);
-    Exception downloadFailure = new CacheNotFoundException(Digest.getDefaultInstance(), digestUtil);
+    Exception downloadFailure = new CacheNotFoundException(Digest.getDefaultInstance());
     doThrow(downloadFailure)
         .when(cache)
         .download(eq(cachedResult), any(Path.class), any(FileOutErr.class), any());
diff --git a/src/test/java/com/google/devtools/build/lib/remote/SimpleBlobStoreActionCacheTest.java b/src/test/java/com/google/devtools/build/lib/remote/SimpleBlobStoreActionCacheTest.java
index 1e3ead4..b44ca79 100644
--- a/src/test/java/com/google/devtools/build/lib/remote/SimpleBlobStoreActionCacheTest.java
+++ b/src/test/java/com/google/devtools/build/lib/remote/SimpleBlobStoreActionCacheTest.java
@@ -34,14 +34,15 @@
 import com.google.common.util.concurrent.ListenableFuture;
 import com.google.common.util.concurrent.ListeningScheduledExecutorService;
 import com.google.common.util.concurrent.MoreExecutors;
-import com.google.common.util.concurrent.SettableFuture;
 import com.google.devtools.build.lib.actions.ActionInputHelper;
 import com.google.devtools.build.lib.clock.JavaClock;
+import com.google.devtools.build.lib.remote.common.CacheNotFoundException;
 import com.google.devtools.build.lib.remote.common.SimpleBlobStore;
 import com.google.devtools.build.lib.remote.common.SimpleBlobStore.ActionKey;
 import com.google.devtools.build.lib.remote.options.RemoteOptions;
 import com.google.devtools.build.lib.remote.util.DigestUtil;
 import com.google.devtools.build.lib.remote.util.TracingMetadataUtils;
+import com.google.devtools.build.lib.remote.util.Utils;
 import com.google.devtools.build.lib.util.io.FileOutErr;
 import com.google.devtools.build.lib.vfs.DigestHashFunction;
 import com.google.devtools.build.lib.vfs.FileSystem;
@@ -451,30 +452,33 @@
       this.map = map;
     }
 
-    @Override
-    public ListenableFuture<Boolean> get(String key, OutputStream out) {
+    private ListenableFuture<Void> get(String key, OutputStream out, Digest digest) {
       byte[] data = map.get(key);
-      SettableFuture<Boolean> f = SettableFuture.create();
       if (data == null) {
-        f.set(false);
+        return Futures.immediateFailedFuture(new CacheNotFoundException(digest));
       } else {
         try {
           out.write(data);
-          f.set(true);
         } catch (IOException e) {
-          f.setException(e);
+          return Futures.immediateFailedFuture(e);
         }
       }
-      return f;
+      return Futures.immediateFuture(null);
     }
 
     @Override
-    public ListenableFuture<Boolean> getActionResult(String key, OutputStream out) {
-      return get(ACTION_KEY_PREFIX + key, out);
+    public ListenableFuture<Void> downloadBlob(Digest digest, OutputStream out) {
+      return get(digest.getHash(), out, digest);
     }
 
     @Override
-    public void putActionResult(ActionKey actionKey, ActionResult actionResult) {
+    public ListenableFuture<ActionResult> downloadActionResult(ActionKey actionKey) {
+      return Utils.downloadAsActionResult(
+          actionKey, (digest, out) -> get(ACTION_KEY_PREFIX + digest.getHash(), out, digest));
+    }
+
+    @Override
+    public void uploadActionResult(ActionKey actionKey, ActionResult actionResult) {
       map.put(ACTION_KEY_PREFIX + actionKey.getDigest().getHash(), actionResult.toByteArray());
     }
 
diff --git a/src/test/java/com/google/devtools/build/lib/remote/http/AbstractHttpHandlerTest.java b/src/test/java/com/google/devtools/build/lib/remote/http/AbstractHttpHandlerTest.java
index 8bb1db9..8f75c75 100644
--- a/src/test/java/com/google/devtools/build/lib/remote/http/AbstractHttpHandlerTest.java
+++ b/src/test/java/com/google/devtools/build/lib/remote/http/AbstractHttpHandlerTest.java
@@ -16,8 +16,11 @@
 
 import static com.google.common.truth.Truth.assertThat;
 
+import build.bazel.remote.execution.v2.Digest;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.Maps;
+import com.google.devtools.build.lib.remote.util.DigestUtil;
+import com.google.devtools.build.lib.vfs.DigestHashFunction;
 import io.netty.channel.ChannelPromise;
 import io.netty.channel.embedded.EmbeddedChannel;
 import io.netty.handler.codec.http.HttpHeaderNames;
@@ -29,18 +32,19 @@
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.JUnit4;
-import org.mockito.Mockito;
 
 /** Tests for {@link AbstractHttpHandlerTest}. */
 @RunWith(JUnit4.class)
 public abstract class AbstractHttpHandlerTest {
 
+  private static final DigestUtil DIGEST_UTIL = new DigestUtil(DigestHashFunction.SHA256);
+  private static final Digest DIGEST = DIGEST_UTIL.computeAsUtf8("foo");
+
   @Test
   public void basicAuthShouldWork() throws Exception {
     URI uri = new URI("http://user:password@does.not.exist/foo");
     EmbeddedChannel ch = new EmbeddedChannel(new HttpDownloadHandler(null, ImmutableList.of()));
-    ByteArrayOutputStream out = Mockito.spy(new ByteArrayOutputStream());
-    DownloadCommand cmd = new DownloadCommand(uri, true, "abcdef", new ByteArrayOutputStream());
+    DownloadCommand cmd = new DownloadCommand(uri, true, DIGEST, new ByteArrayOutputStream());
     ChannelPromise writePromise = ch.newPromise();
     ch.writeOneOutbound(cmd, writePromise);
 
@@ -53,8 +57,7 @@
   public void basicAuthShouldNotEnabled() throws Exception {
     URI uri = new URI("http://does.not.exist/foo");
     EmbeddedChannel ch = new EmbeddedChannel(new HttpDownloadHandler(null, ImmutableList.of()));
-    ByteArrayOutputStream out = Mockito.spy(new ByteArrayOutputStream());
-    DownloadCommand cmd = new DownloadCommand(uri, true, "abcdef", new ByteArrayOutputStream());
+    DownloadCommand cmd = new DownloadCommand(uri, true, DIGEST, new ByteArrayOutputStream());
     ChannelPromise writePromise = ch.newPromise();
     ch.writeOneOutbound(cmd, writePromise);
 
@@ -66,8 +69,7 @@
   public void hostDoesntIncludePortHttp() throws Exception {
     URI uri = new URI("http://does.not.exist/foo");
     EmbeddedChannel ch = new EmbeddedChannel(new HttpDownloadHandler(null, ImmutableList.of()));
-    ByteArrayOutputStream out = Mockito.spy(new ByteArrayOutputStream());
-    DownloadCommand cmd = new DownloadCommand(uri, true, "abcdef", new ByteArrayOutputStream());
+    DownloadCommand cmd = new DownloadCommand(uri, true, DIGEST, new ByteArrayOutputStream());
     ChannelPromise writePromise = ch.newPromise();
     ch.writeOneOutbound(cmd, writePromise);
 
@@ -79,8 +81,7 @@
   public void hostDoesntIncludePortHttps() throws Exception {
     URI uri = new URI("https://does.not.exist/foo");
     EmbeddedChannel ch = new EmbeddedChannel(new HttpDownloadHandler(null, ImmutableList.of()));
-    ByteArrayOutputStream out = Mockito.spy(new ByteArrayOutputStream());
-    DownloadCommand cmd = new DownloadCommand(uri, true, "abcdef", new ByteArrayOutputStream());
+    DownloadCommand cmd = new DownloadCommand(uri, true, DIGEST, new ByteArrayOutputStream());
     ChannelPromise writePromise = ch.newPromise();
     ch.writeOneOutbound(cmd, writePromise);
 
@@ -92,8 +93,7 @@
   public void hostDoesIncludePort() throws Exception {
     URI uri = new URI("http://does.not.exist:8080/foo");
     EmbeddedChannel ch = new EmbeddedChannel(new HttpDownloadHandler(null, ImmutableList.of()));
-    ByteArrayOutputStream out = Mockito.spy(new ByteArrayOutputStream());
-    DownloadCommand cmd = new DownloadCommand(uri, true, "abcdef", new ByteArrayOutputStream());
+    DownloadCommand cmd = new DownloadCommand(uri, true, DIGEST, new ByteArrayOutputStream());
     ChannelPromise writePromise = ch.newPromise();
     ch.writeOneOutbound(cmd, writePromise);
 
@@ -107,8 +107,7 @@
     EmbeddedChannel ch =
         new EmbeddedChannel(new HttpDownloadHandler(/* credentials= */ null, ImmutableList.of()));
     DownloadCommand cmd =
-        new DownloadCommand(
-            uri, /* casDownload= */ true, /* hash= */ "abcdef", new ByteArrayOutputStream());
+        new DownloadCommand(uri, /* casDownload= */ true, DIGEST, new ByteArrayOutputStream());
     ChannelPromise writePromise = ch.newPromise();
     ch.writeOneOutbound(cmd, writePromise);
 
@@ -126,8 +125,7 @@
     EmbeddedChannel ch =
         new EmbeddedChannel(new HttpDownloadHandler(/* credentials= */ null, remoteHeaders));
     DownloadCommand cmd =
-        new DownloadCommand(
-            uri, /* casDownload= */ true, /* hash= */ "abcdef", new ByteArrayOutputStream());
+        new DownloadCommand(uri, /* casDownload= */ true, DIGEST, new ByteArrayOutputStream());
     ChannelPromise writePromise = ch.newPromise();
     ch.writeOneOutbound(cmd, writePromise);
 
@@ -146,8 +144,7 @@
     EmbeddedChannel ch =
         new EmbeddedChannel(new HttpDownloadHandler(/* credentials= */ null, remoteHeaders));
     DownloadCommand cmd =
-        new DownloadCommand(
-            uri, /* casDownload= */ true, /* hash= */ "abcdef", new ByteArrayOutputStream());
+        new DownloadCommand(uri, /* casDownload= */ true, DIGEST, new ByteArrayOutputStream());
     ChannelPromise writePromise = ch.newPromise();
     ch.writeOneOutbound(cmd, writePromise);
 
diff --git a/src/test/java/com/google/devtools/build/lib/remote/http/HttpBlobStoreTest.java b/src/test/java/com/google/devtools/build/lib/remote/http/HttpBlobStoreTest.java
index 501bd7c..b959c43 100644
--- a/src/test/java/com/google/devtools/build/lib/remote/http/HttpBlobStoreTest.java
+++ b/src/test/java/com/google/devtools/build/lib/remote/http/HttpBlobStoreTest.java
@@ -97,6 +97,7 @@
 public class HttpBlobStoreTest {
 
   private static final DigestUtil DIGEST_UTIL = new DigestUtil(DigestHashFunction.SHA256);
+  private static final Digest DIGEST = DIGEST_UTIL.computeAsUtf8("foo");
 
   private static ServerChannel createServer(
       Class<? extends ServerChannel> serverChannelClass,
@@ -308,7 +309,7 @@
 
     Credentials credentials = newCredentials();
     HttpBlobStore blobStore = createHttpBlobStore(server, /* timeoutSeconds= */ 1, credentials);
-    getFromFuture(blobStore.get("key", new ByteArrayOutputStream()));
+    getFromFuture(blobStore.downloadBlob(DIGEST, new ByteArrayOutputStream()));
 
     fail("Exception expected");
   }
@@ -353,7 +354,7 @@
 
       Credentials credentials = newCredentials();
       HttpBlobStore blobStore = createHttpBlobStore(server, /* timeoutSeconds= */ 1, credentials);
-      getFromFuture(blobStore.get("key", new ByteArrayOutputStream()));
+      getFromFuture(blobStore.downloadBlob(DIGEST, new ByteArrayOutputStream()));
       fail("Exception expected");
     } finally {
       testServer.stop(server);
@@ -415,7 +416,7 @@
       Credentials credentials = newCredentials();
       HttpBlobStore blobStore = createHttpBlobStore(server, /* timeoutSeconds= */ 1, credentials);
       ByteArrayOutputStream out = Mockito.spy(new ByteArrayOutputStream());
-      getFromFuture(blobStore.get("key", out));
+      getFromFuture(blobStore.downloadBlob(DIGEST, out));
       assertThat(out.toString(Charsets.US_ASCII.name())).isEqualTo("File Contents");
       verify(credentials, times(1)).refresh();
       verify(credentials, times(2)).getRequestMetadata(any(URI.class));
@@ -471,7 +472,7 @@
 
       Credentials credentials = newCredentials();
       HttpBlobStore blobStore = createHttpBlobStore(server, /* timeoutSeconds= */ 1, credentials);
-      getFromFuture(blobStore.get("key", new ByteArrayOutputStream()));
+      getFromFuture(blobStore.downloadBlob(DIGEST, new ByteArrayOutputStream()));
       fail("Exception expected.");
     } catch (Exception e) {
       assertThat(e).isInstanceOf(HttpException.class);
diff --git a/src/test/java/com/google/devtools/build/lib/remote/http/HttpDownloadHandlerTest.java b/src/test/java/com/google/devtools/build/lib/remote/http/HttpDownloadHandlerTest.java
index a70b3b4..289b322 100644
--- a/src/test/java/com/google/devtools/build/lib/remote/http/HttpDownloadHandlerTest.java
+++ b/src/test/java/com/google/devtools/build/lib/remote/http/HttpDownloadHandlerTest.java
@@ -17,8 +17,11 @@
 import static org.mockito.Mockito.never;
 import static org.mockito.Mockito.verify;
 
+import build.bazel.remote.execution.v2.Digest;
 import com.google.common.collect.ImmutableList;
 import com.google.common.net.HttpHeaders;
+import com.google.devtools.build.lib.remote.util.DigestUtil;
+import com.google.devtools.build.lib.vfs.DigestHashFunction;
 import io.netty.buffer.ByteBuf;
 import io.netty.buffer.ByteBufUtil;
 import io.netty.buffer.Unpooled;
@@ -48,6 +51,8 @@
 public class HttpDownloadHandlerTest extends AbstractHttpHandlerTest {
 
   private static final URI CACHE_URI = URI.create("http://storage.googleapis.com:80/cache-bucket");
+  private static final DigestUtil DIGEST_UTIL = new DigestUtil(DigestHashFunction.SHA256);
+  private static final Digest DIGEST = DIGEST_UTIL.computeAsUtf8("foo");
 
   /**
    * Test that downloading blobs works from both the Action Cache and the CAS. Also test that the
@@ -62,7 +67,7 @@
 
   private void downloadShouldWork(boolean casDownload, EmbeddedChannel ch) throws IOException {
     ByteArrayOutputStream out = Mockito.spy(new ByteArrayOutputStream());
-    DownloadCommand cmd = new DownloadCommand(CACHE_URI, casDownload, "abcdef", out);
+    DownloadCommand cmd = new DownloadCommand(CACHE_URI, casDownload, DIGEST, out);
     ChannelPromise writePromise = ch.newPromise();
     ch.writeOneOutbound(cmd, writePromise);
 
@@ -70,9 +75,9 @@
     assertThat(request.method()).isEqualTo(HttpMethod.GET);
     assertThat(request.headers().get(HttpHeaderNames.HOST)).isEqualTo(CACHE_URI.getHost());
     if (casDownload) {
-      assertThat(request.uri()).isEqualTo("/cache-bucket/cas/abcdef");
+      assertThat(request.uri()).isEqualTo("/cache-bucket/cas/" + DIGEST.getHash());
     } else {
-      assertThat(request.uri()).isEqualTo("/cache-bucket/ac/abcdef");
+      assertThat(request.uri()).isEqualTo("/cache-bucket/ac/" + DIGEST.getHash());
     }
 
     assertThat(writePromise.isDone()).isFalse();
@@ -96,7 +101,7 @@
   public void httpErrorsAreSupported() throws IOException {
     EmbeddedChannel ch = new EmbeddedChannel(new HttpDownloadHandler(null, ImmutableList.of()));
     ByteArrayOutputStream out = Mockito.spy(new ByteArrayOutputStream());
-    DownloadCommand cmd = new DownloadCommand(CACHE_URI, true, "abcdef", out);
+    DownloadCommand cmd = new DownloadCommand(CACHE_URI, true, DIGEST, out);
     ChannelPromise writePromise = ch.newPromise();
     ch.writeOneOutbound(cmd, writePromise);
 
@@ -126,7 +131,7 @@
   public void httpErrorsWithContentAreSupported() throws IOException {
     EmbeddedChannel ch = new EmbeddedChannel(new HttpDownloadHandler(null, ImmutableList.of()));
     ByteArrayOutputStream out = Mockito.spy(new ByteArrayOutputStream());
-    DownloadCommand cmd = new DownloadCommand(CACHE_URI, true, "abcdef", out);
+    DownloadCommand cmd = new DownloadCommand(CACHE_URI, true, DIGEST, out);
     ChannelPromise writePromise = ch.newPromise();
     ch.writeOneOutbound(cmd, writePromise);
 
diff --git a/src/tools/remote/src/main/java/com/google/devtools/build/remote/worker/ByteStreamServer.java b/src/tools/remote/src/main/java/com/google/devtools/build/remote/worker/ByteStreamServer.java
index b4a4b25..79a52b5 100644
--- a/src/tools/remote/src/main/java/com/google/devtools/build/remote/worker/ByteStreamServer.java
+++ b/src/tools/remote/src/main/java/com/google/devtools/build/remote/worker/ByteStreamServer.java
@@ -24,8 +24,8 @@
 import com.google.bytestream.ByteStreamProto.ReadResponse;
 import com.google.bytestream.ByteStreamProto.WriteRequest;
 import com.google.bytestream.ByteStreamProto.WriteResponse;
-import com.google.devtools.build.lib.remote.CacheNotFoundException;
 import com.google.devtools.build.lib.remote.Chunker;
+import com.google.devtools.build.lib.remote.common.CacheNotFoundException;
 import com.google.devtools.build.lib.remote.util.DigestUtil;
 import com.google.devtools.build.lib.vfs.FileSystemUtils;
 import com.google.devtools.build.lib.vfs.Path;
diff --git a/src/tools/remote/src/main/java/com/google/devtools/build/remote/worker/ExecutionServer.java b/src/tools/remote/src/main/java/com/google/devtools/build/remote/worker/ExecutionServer.java
index 925c944..3036a80 100644
--- a/src/tools/remote/src/main/java/com/google/devtools/build/remote/worker/ExecutionServer.java
+++ b/src/tools/remote/src/main/java/com/google/devtools/build/remote/worker/ExecutionServer.java
@@ -37,9 +37,9 @@
 import com.google.common.util.concurrent.MoreExecutors;
 import com.google.common.util.concurrent.ThreadFactoryBuilder;
 import com.google.devtools.build.lib.actions.ExecException;
-import com.google.devtools.build.lib.remote.CacheNotFoundException;
 import com.google.devtools.build.lib.remote.ExecutionStatusException;
 import com.google.devtools.build.lib.remote.SimpleBlobStoreActionCache;
+import com.google.devtools.build.lib.remote.common.CacheNotFoundException;
 import com.google.devtools.build.lib.remote.common.SimpleBlobStore.ActionKey;
 import com.google.devtools.build.lib.remote.util.DigestUtil;
 import com.google.devtools.build.lib.remote.util.TracingMetadataUtils;
diff --git a/src/tools/remote/src/main/java/com/google/devtools/build/remote/worker/OnDiskBlobStoreActionCache.java b/src/tools/remote/src/main/java/com/google/devtools/build/remote/worker/OnDiskBlobStoreActionCache.java
index c038d2e..3f34329 100644
--- a/src/tools/remote/src/main/java/com/google/devtools/build/remote/worker/OnDiskBlobStoreActionCache.java
+++ b/src/tools/remote/src/main/java/com/google/devtools/build/remote/worker/OnDiskBlobStoreActionCache.java
@@ -28,6 +28,6 @@
   }
 
   public boolean containsKey(Digest digest) {
-    return ((OnDiskBlobStore) blobStore).contains(digest.getHash());
+    return ((OnDiskBlobStore) blobStore).contains(digest);
   }
 }