| /** |
| * 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.ipc; |
| |
| import org.apache.commons.lang.builder.EqualsBuilder; |
| import org.apache.commons.lang.builder.HashCodeBuilder; |
| import org.apache.hadoop.classification.InterfaceAudience; |
| import org.apache.hadoop.classification.InterfaceStability; |
| |
| import java.nio.charset.Charset; |
| import java.nio.charset.StandardCharsets; |
| import java.util.Arrays; |
| |
| /** |
| * A class defining the caller context for auditing coarse granularity |
| * operations. |
| * |
| * This class is immutable. |
| */ |
| @InterfaceAudience.LimitedPrivate({"HBase", "HDFS", "Hive", "MapReduce", |
| "Pig", "Spark", "YARN"}) |
| @InterfaceStability.Evolving |
| public class CallerContext { |
| public static final Charset SIGNATURE_ENCODING = StandardCharsets.UTF_8; |
| /** The caller context. |
| * |
| * It will be truncated if it exceeds the maximum allowed length in |
| * server. The default length limit is |
| * {@link org.apache.hadoop.fs.CommonConfigurationKeysPublic#HADOOP_CALLER_CONTEXT_MAX_SIZE_DEFAULT} |
| */ |
| private final String context; |
| |
| /** The caller's signature for validation. |
| * |
| * The signature is optional. The null or empty signature will be abandoned. |
| * If the signature exceeds the maximum allowed length in server, the caller |
| * context will be abandoned. The default length limit is |
| * {@link org.apache.hadoop.fs.CommonConfigurationKeysPublic#HADOOP_CALLER_CONTEXT_SIGNATURE_MAX_SIZE_DEFAULT} |
| */ |
| private final byte[] signature; |
| |
| public CallerContext(Builder builder) { |
| this.context = builder.context; |
| this.signature = builder.signature; |
| } |
| |
| public String getContext() { |
| return context; |
| } |
| |
| public byte[] getSignature() { |
| return signature == null ? |
| null : Arrays.copyOf(signature, signature.length); |
| } |
| |
| @InterfaceAudience.Private |
| public boolean isContextValid() { |
| return context != null && !context.isEmpty(); |
| } |
| |
| @Override |
| public int hashCode() { |
| return new HashCodeBuilder().append(context).toHashCode(); |
| } |
| |
| @Override |
| public boolean equals(Object obj) { |
| if (obj == null) { |
| return false; |
| } else if (obj == this) { |
| return true; |
| } else if (obj.getClass() != getClass()) { |
| return false; |
| } else { |
| CallerContext rhs = (CallerContext) obj; |
| return new EqualsBuilder() |
| .append(context, rhs.context) |
| .append(signature, rhs.signature) |
| .isEquals(); |
| } |
| } |
| |
| @Override |
| public String toString() { |
| if (!isContextValid()) { |
| return ""; |
| } |
| String str = context; |
| if (signature != null) { |
| str += ":"; |
| str += new String(signature, SIGNATURE_ENCODING); |
| } |
| return str; |
| } |
| |
| /** The caller context builder. */ |
| public static final class Builder { |
| private final String context; |
| private byte[] signature; |
| |
| public Builder(String context) { |
| this.context = context; |
| } |
| |
| public Builder setSignature(byte[] signature) { |
| if (signature != null && signature.length > 0) { |
| this.signature = Arrays.copyOf(signature, signature.length); |
| } |
| return this; |
| } |
| |
| public CallerContext build() { |
| return new CallerContext(this); |
| } |
| } |
| |
| /** |
| * The thread local current caller context. |
| * <p/> |
| * Internal class for defered singleton idiom. |
| * https://en.wikipedia.org/wiki/Initialization_on_demand_holder_idiom |
| */ |
| private static final class CurrentCallerContextHolder { |
| static final ThreadLocal<CallerContext> CALLER_CONTEXT = |
| new InheritableThreadLocal<>(); |
| } |
| |
| public static CallerContext getCurrent() { |
| return CurrentCallerContextHolder.CALLER_CONTEXT.get(); |
| } |
| |
| public static void setCurrent(CallerContext callerContext) { |
| CurrentCallerContextHolder.CALLER_CONTEXT.set(callerContext); |
| } |
| } |