| /** |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you 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 org.apache.hadoop.crypto.key; |
| |
| import java.io.IOException; |
| import java.security.NoSuchAlgorithmException; |
| import java.util.concurrent.ExecutionException; |
| import java.util.concurrent.TimeUnit; |
| |
| import com.google.common.cache.CacheBuilder; |
| import com.google.common.cache.CacheLoader; |
| import com.google.common.cache.LoadingCache; |
| |
| /** |
| * A <code>KeyProviderExtension</code> implementation providing a short lived |
| * cache for <code>KeyVersions</code> and <code>Metadata</code>to avoid burst |
| * of requests to hit the underlying <code>KeyProvider</code>. |
| */ |
| public class CachingKeyProvider extends |
| KeyProviderExtension<CachingKeyProvider.CacheExtension> { |
| |
| static class CacheExtension implements KeyProviderExtension.Extension { |
| private final KeyProvider provider; |
| private LoadingCache<String, KeyVersion> keyVersionCache; |
| private LoadingCache<String, KeyVersion> currentKeyCache; |
| private LoadingCache<String, Metadata> keyMetadataCache; |
| |
| CacheExtension(KeyProvider prov, long keyTimeoutMillis, |
| long currKeyTimeoutMillis) { |
| this.provider = prov; |
| keyVersionCache = |
| CacheBuilder.newBuilder().expireAfterAccess(keyTimeoutMillis, |
| TimeUnit.MILLISECONDS) |
| .build(new CacheLoader<String, KeyVersion>() { |
| @Override |
| public KeyVersion load(String key) throws Exception { |
| KeyVersion kv = provider.getKeyVersion(key); |
| if (kv == null) { |
| throw new KeyNotFoundException(); |
| } |
| return kv; |
| } |
| }); |
| keyMetadataCache = |
| CacheBuilder.newBuilder().expireAfterAccess(keyTimeoutMillis, |
| TimeUnit.MILLISECONDS) |
| .build(new CacheLoader<String, Metadata>() { |
| @Override |
| public Metadata load(String key) throws Exception { |
| Metadata meta = provider.getMetadata(key); |
| if (meta == null) { |
| throw new KeyNotFoundException(); |
| } |
| return meta; |
| } |
| }); |
| currentKeyCache = |
| CacheBuilder.newBuilder().expireAfterWrite(currKeyTimeoutMillis, |
| TimeUnit.MILLISECONDS) |
| .build(new CacheLoader<String, KeyVersion>() { |
| @Override |
| public KeyVersion load(String key) throws Exception { |
| KeyVersion kv = provider.getCurrentKey(key); |
| if (kv == null) { |
| throw new KeyNotFoundException(); |
| } |
| return kv; |
| } |
| }); |
| } |
| } |
| |
| @SuppressWarnings("serial") |
| private static class KeyNotFoundException extends Exception { } |
| |
| public CachingKeyProvider(KeyProvider keyProvider, long keyTimeoutMillis, |
| long currKeyTimeoutMillis) { |
| super(keyProvider, new CacheExtension(keyProvider, keyTimeoutMillis, |
| currKeyTimeoutMillis)); |
| } |
| |
| @Override |
| public KeyVersion getCurrentKey(String name) throws IOException { |
| try { |
| return getExtension().currentKeyCache.get(name); |
| } catch (ExecutionException ex) { |
| Throwable cause = ex.getCause(); |
| if (cause instanceof KeyNotFoundException) { |
| return null; |
| } else if (cause instanceof IOException) { |
| throw (IOException) cause; |
| } else { |
| throw new IOException(cause); |
| } |
| } |
| } |
| |
| @Override |
| public KeyVersion getKeyVersion(String versionName) |
| throws IOException { |
| try { |
| return getExtension().keyVersionCache.get(versionName); |
| } catch (ExecutionException ex) { |
| Throwable cause = ex.getCause(); |
| if (cause instanceof KeyNotFoundException) { |
| return null; |
| } else if (cause instanceof IOException) { |
| throw (IOException) cause; |
| } else { |
| throw new IOException(cause); |
| } |
| } |
| } |
| |
| @Override |
| public void deleteKey(String name) throws IOException { |
| getKeyProvider().deleteKey(name); |
| getExtension().currentKeyCache.invalidate(name); |
| getExtension().keyMetadataCache.invalidate(name); |
| // invalidating all key versions as we don't know |
| // which ones belonged to the deleted key |
| getExtension().keyVersionCache.invalidateAll(); |
| } |
| |
| @Override |
| public KeyVersion rollNewVersion(String name, byte[] material) |
| throws IOException { |
| KeyVersion key = getKeyProvider().rollNewVersion(name, material); |
| getExtension().currentKeyCache.invalidate(name); |
| getExtension().keyMetadataCache.invalidate(name); |
| return key; |
| } |
| |
| @Override |
| public KeyVersion rollNewVersion(String name) |
| throws NoSuchAlgorithmException, IOException { |
| KeyVersion key = getKeyProvider().rollNewVersion(name); |
| getExtension().currentKeyCache.invalidate(name); |
| getExtension().keyMetadataCache.invalidate(name); |
| return key; |
| } |
| |
| @Override |
| public Metadata getMetadata(String name) throws IOException { |
| try { |
| return getExtension().keyMetadataCache.get(name); |
| } catch (ExecutionException ex) { |
| Throwable cause = ex.getCause(); |
| if (cause instanceof KeyNotFoundException) { |
| return null; |
| } else if (cause instanceof IOException) { |
| throw (IOException) cause; |
| } else { |
| throw new IOException(cause); |
| } |
| } |
| } |
| |
| } |