| // Copyright 2017 The Bazel Authors. All rights reserved. |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| package com.google.devtools.build.lib.remote.blobstore; |
| |
| import static com.google.devtools.build.lib.remote.util.Utils.getFromFuture; |
| |
| import com.google.common.io.ByteStreams; |
| import com.google.common.util.concurrent.ListenableFuture; |
| import com.google.common.util.concurrent.SettableFuture; |
| import com.google.devtools.build.lib.vfs.Path; |
| import java.io.ByteArrayInputStream; |
| import java.io.IOException; |
| import java.io.InputStream; |
| import java.io.OutputStream; |
| import java.util.UUID; |
| |
| /** A on-disk store for the remote action cache. */ |
| public class OnDiskBlobStore implements SimpleBlobStore { |
| private final Path root; |
| static final String ACTION_KEY_PREFIX = "ac_"; |
| |
| public OnDiskBlobStore(Path root) { |
| this.root = root; |
| } |
| |
| @Override |
| public boolean containsKey(String key) { |
| return toPath(key).exists(); |
| } |
| |
| @Override |
| public ListenableFuture<Boolean> get(String key, OutputStream out) { |
| SettableFuture<Boolean> f = SettableFuture.create(); |
| Path p = toPath(key); |
| if (!p.exists()) { |
| f.set(false); |
| } else { |
| try (InputStream in = p.getInputStream()) { |
| ByteStreams.copy(in, out); |
| f.set(true); |
| } catch (IOException e) { |
| f.setException(e); |
| } |
| } |
| return f; |
| } |
| |
| @Override |
| public boolean getActionResult(String key, OutputStream out) |
| throws IOException, InterruptedException { |
| return getFromFuture(get(ACTION_KEY_PREFIX + key, out)); |
| } |
| |
| @Override |
| public void put(String key, long length, InputStream in) |
| throws IOException, InterruptedException { |
| Path target = toPath(key); |
| if (target.exists()) { |
| return; |
| } |
| |
| // Write a temporary file first, and then rename, to avoid data corruption in case of a crash. |
| Path temp = toPath(UUID.randomUUID().toString()); |
| try (OutputStream out = temp.getOutputStream()) { |
| ByteStreams.copy(in, out); |
| } |
| // 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); |
| } |
| |
| @Override |
| public void putActionResult(String key, byte[] in) throws IOException, InterruptedException { |
| put(ACTION_KEY_PREFIX + key, in.length, new ByteArrayInputStream(in)); |
| } |
| |
| @Override |
| public void close() {} |
| |
| protected Path toPath(String key) { |
| return root.getChild(key); |
| } |
| } |