| /* |
| * 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.druid.segment.metadata; |
| |
| import com.fasterxml.jackson.databind.ObjectMapper; |
| import com.google.common.hash.Hasher; |
| import com.google.common.hash.Hashing; |
| import com.google.common.io.BaseEncoding; |
| import com.google.common.primitives.Ints; |
| import com.google.inject.Inject; |
| import org.apache.druid.guice.LazySingleton; |
| import org.apache.druid.java.util.common.StringUtils; |
| import org.apache.druid.java.util.common.logger.Logger; |
| import org.apache.druid.segment.SchemaPayload; |
| |
| import java.io.IOException; |
| |
| /** |
| * Utility to generate fingerprint for an object. |
| */ |
| @LazySingleton |
| public class FingerprintGenerator |
| { |
| private static final Logger log = new Logger(FingerprintGenerator.class); |
| |
| private final ObjectMapper objectMapper; |
| |
| @Inject |
| public FingerprintGenerator(ObjectMapper objectMapper) |
| { |
| this.objectMapper = objectMapper; |
| } |
| |
| /** |
| * Generates fingerprint or hash string for an object using SHA-256 hash algorithm. |
| */ |
| @SuppressWarnings("UnstableApiUsage") |
| public String generateFingerprint(SchemaPayload schemaPayload, String dataSource, int version) |
| { |
| try { |
| final Hasher hasher = Hashing.sha256().newHasher(); |
| |
| hasher.putBytes(objectMapper.writeValueAsBytes(schemaPayload)); |
| // add delimiter, inspired from org.apache.druid.metadata.PendingSegmentRecord.computeSequenceNamePrevIdSha1 |
| hasher.putByte((byte) 0xff); |
| |
| hasher.putBytes(StringUtils.toUtf8(dataSource)); |
| hasher.putByte((byte) 0xff); |
| |
| hasher.putBytes(Ints.toByteArray(version)); |
| hasher.putByte((byte) 0xff); |
| |
| return BaseEncoding.base16().encode(hasher.hash().asBytes()); |
| } |
| catch (IOException e) { |
| log.error( |
| "Exception generating fingerprint for payload [%s], datasource [%s], version [%s] with stacktrace [%s].", |
| schemaPayload, |
| dataSource, |
| version, |
| e |
| ); |
| throw new RuntimeException(e); |
| } |
| } |
| } |