001/* 002 * (C) Copyright 2006-2016 Nuxeo SA (http://nuxeo.com/) and others. 003 * 004 * Licensed under the Apache License, Version 2.0 (the "License"); 005 * you may not use this file except in compliance with the License. 006 * You may obtain a copy of the License at 007 * 008 * http://www.apache.org/licenses/LICENSE-2.0 009 * 010 * Unless required by applicable law or agreed to in writing, software 011 * distributed under the License is distributed on an "AS IS" BASIS, 012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 013 * See the License for the specific language governing permissions and 014 * limitations under the License. 015 * 016 * Contributors: 017 * Nuxeo - initial API and implementation 018 */ 019package org.nuxeo.ecm.platform.filemanager.core.listener; 020 021import static org.nuxeo.ecm.core.api.event.DocumentEventTypes.ABOUT_TO_CREATE; 022import static org.nuxeo.ecm.core.api.event.DocumentEventTypes.BEFORE_DOC_UPDATE; 023 024import java.io.IOException; 025import java.security.MessageDigest; 026import java.security.NoSuchAlgorithmException; 027import java.util.List; 028 029import org.apache.commons.codec.binary.Base64; 030import org.apache.commons.codec.digest.DigestUtils; 031import org.apache.commons.logging.Log; 032import org.apache.commons.logging.LogFactory; 033import org.nuxeo.ecm.core.api.Blob; 034import org.nuxeo.ecm.core.api.DocumentModel; 035import org.nuxeo.ecm.core.api.PropertyException; 036import org.nuxeo.ecm.core.api.model.Property; 037import org.nuxeo.ecm.core.event.Event; 038import org.nuxeo.ecm.core.event.EventContext; 039import org.nuxeo.ecm.core.event.EventListener; 040import org.nuxeo.ecm.core.event.impl.DocumentEventContext; 041import org.nuxeo.ecm.platform.filemanager.api.FileManager; 042import org.nuxeo.runtime.api.Framework; 043 044public class DigestComputer implements EventListener { 045 046 private boolean initDone = false; 047 048 private List<String> xpathFields; 049 050 private String digestAlgo = "sha-256"; 051 052 private Boolean activateDigestComputation = false; 053 054 private static final Log log = LogFactory.getLog(DigestComputer.class); 055 056 private boolean initIfNeeded() { 057 if (!initDone) { 058 FileManager fm = Framework.getService(FileManager.class); 059 xpathFields = fm.getFields(); 060 digestAlgo = fm.getDigestAlgorithm(); 061 activateDigestComputation = fm.isDigestComputingEnabled(); 062 initDone = true; 063 } 064 return initDone; 065 } 066 067 private void addDigestToDocument(DocumentModel doc) { 068 for (String xpathField : xpathFields) { 069 Property blobProp = null; 070 try { 071 blobProp = doc.getProperty(xpathField); 072 } catch (PropertyException e) { 073 log.debug("Property " + xpathField + " not found on doc, skipping"); 074 } 075 if (blobProp != null && !blobProp.isPhantom() && blobProp.isDirty()) { 076 try { 077 Blob blob = (Blob) blobProp.getValue(); 078 if (blob != null) { 079 String digest = computeDigest(blob); 080 if (!digest.equals(blob.getDigest())) { 081 blob.setDigest(digest); 082 } 083 } 084 } catch (PropertyException | IOException e) { 085 log.error("Error while trying to save blob digest", e); 086 } 087 } 088 } 089 } 090 091 private String computeDigest(Blob blob) throws IOException { 092 093 MessageDigest md; 094 try { 095 md = MessageDigest.getInstance(digestAlgo); 096 } catch (NoSuchAlgorithmException e) { 097 throw new RuntimeException(e); 098 } 099 byte[] b = DigestUtils.updateDigest(md, blob.getStream()).digest(); 100 return Base64.encodeBase64String(b); 101 } 102 103 public void handleEvent(Event event) { 104 if (!initIfNeeded()) { 105 return; 106 } 107 108 if (!activateDigestComputation) { 109 return; 110 } 111 112 EventContext ctx = event.getContext(); 113 String evt = event.getName(); 114 if (ABOUT_TO_CREATE.equals(evt) || BEFORE_DOC_UPDATE.equals(evt)) { 115 116 if (ctx instanceof DocumentEventContext) { 117 DocumentEventContext docCtx = (DocumentEventContext) ctx; 118 DocumentModel doc = docCtx.getSourceDocument(); 119 if (doc == null || doc.isProxy()) { 120 return; 121 } 122 addDigestToDocument(doc); 123 } 124 } 125 } 126 127}