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 static final Log log = LogFactory.getLog(DigestComputer.class); 047 048 private void addDigestToDocument(DocumentModel doc) { 049 FileManager fm = Framework.getService(FileManager.class); 050 List<String> xpathFields = fm.getFields(); 051 String digestAlgo = fm.getDigestAlgorithm(); 052 for (String xpathField : xpathFields) { 053 Property blobProp = null; 054 try { 055 blobProp = doc.getProperty(xpathField); 056 } catch (PropertyException e) { 057 log.debug("Property " + xpathField + " not found on doc, skipping"); 058 } 059 if (blobProp != null && !blobProp.isPhantom() && blobProp.isDirty()) { 060 try { 061 Blob blob = (Blob) blobProp.getValue(); 062 if (blob != null) { 063 String digest = computeDigest(blob, digestAlgo); 064 if (!digest.equals(blob.getDigest())) { 065 blob.setDigest(digest); 066 } 067 } 068 } catch (PropertyException | IOException e) { 069 log.error("Error while trying to save blob digest", e); 070 } 071 } 072 } 073 } 074 075 private String computeDigest(Blob blob, String digestAlgo) throws IOException { 076 077 MessageDigest md; 078 try { 079 md = MessageDigest.getInstance(digestAlgo); 080 } catch (NoSuchAlgorithmException e) { 081 throw new RuntimeException(e); 082 } 083 byte[] b = DigestUtils.updateDigest(md, blob.getStream()).digest(); 084 return Base64.encodeBase64String(b); 085 } 086 087 @Override 088 public void handleEvent(Event event) { 089 FileManager fm = Framework.getService(FileManager.class); 090 if (!fm.isDigestComputingEnabled()) { 091 return; 092 } 093 094 EventContext ctx = event.getContext(); 095 String evt = event.getName(); 096 if (ABOUT_TO_CREATE.equals(evt) || BEFORE_DOC_UPDATE.equals(evt)) { 097 098 if (ctx instanceof DocumentEventContext) { 099 DocumentEventContext docCtx = (DocumentEventContext) ctx; 100 DocumentModel doc = docCtx.getSourceDocument(); 101 if (doc == null || doc.isProxy()) { 102 return; 103 } 104 addDigestToDocument(doc); 105 } 106 } 107 } 108 109}