001/* 002 * (C) Copyright 2015 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 */ 019 020package org.nuxeo.ecm.platform.rendition.lazy; 021 022import java.security.MessageDigest; 023import java.security.NoSuchAlgorithmException; 024import java.util.ArrayList; 025import java.util.Calendar; 026import java.util.List; 027 028import org.apache.commons.logging.Log; 029import org.apache.commons.logging.LogFactory; 030import org.nuxeo.ecm.core.api.Blob; 031import org.nuxeo.ecm.core.api.DocumentModel; 032import org.nuxeo.ecm.core.api.NuxeoException; 033import org.nuxeo.ecm.core.api.impl.blob.StringBlob; 034import org.nuxeo.ecm.core.transientstore.api.TransientStore; 035import org.nuxeo.ecm.core.transientstore.api.TransientStoreService; 036import org.nuxeo.ecm.core.work.api.Work; 037import org.nuxeo.ecm.core.work.api.WorkManager; 038import org.nuxeo.ecm.core.work.api.WorkManager.Scheduling; 039import org.nuxeo.ecm.platform.rendition.Rendition; 040import org.nuxeo.ecm.platform.rendition.extension.AutomationRenderer; 041import org.nuxeo.ecm.platform.rendition.extension.RenditionProvider; 042import org.nuxeo.ecm.platform.rendition.impl.LazyRendition; 043import org.nuxeo.ecm.platform.rendition.service.RenditionDefinition; 044import org.nuxeo.runtime.api.Framework; 045 046/** 047 * Default implementation of an asynchronous {@link RenditionProvider} 048 * 049 * @author <a href="mailto:tdelprat@nuxeo.com">Tiry</a> 050 * @since 7.2 051 */ 052public abstract class AbstractLazyCachableRenditionProvider implements RenditionProvider { 053 054 public static final String WORKERID_KEY = "workerid"; 055 056 public static final String CACHE_NAME = "LazyRenditionCache"; 057 058 protected static Log log = LogFactory.getLog(AbstractLazyCachableRenditionProvider.class); 059 060 @Override 061 public List<Blob> render(DocumentModel doc, RenditionDefinition def) { 062 063 // build the key 064 String key = buildRenditionKey(doc, def); 065 066 // see if rendition is already in process 067 068 TransientStoreService tss = Framework.getService(TransientStoreService.class); 069 070 TransientStore ts = tss.getStore(CACHE_NAME); 071 072 if (ts == null) { 073 throw new NuxeoException("Unable to find Transient Store " + CACHE_NAME); 074 } 075 076 List<Blob> blobs = null; 077 if (!ts.exists(key)) { 078 Work work = getRenditionWork(key, doc, def); 079 ts.putParameter(key, WORKERID_KEY, work.getId()); 080 blobs = new ArrayList<>(); 081 StringBlob emptyBlob = new StringBlob(""); 082 emptyBlob.setFilename("inprogress"); 083 emptyBlob.setMimeType("text/plain;" + LazyRendition.EMPTY_MARKER); 084 blobs.add(emptyBlob); 085 ts.putBlobs(key, blobs); 086 Framework.getService(WorkManager.class).schedule(work, Scheduling.IF_NOT_SCHEDULED); 087 blobs = ts.getBlobs(key); 088 } else { 089 blobs = ts.getBlobs(key); 090 if (ts.isCompleted(key)) { 091 if (blobs != null && blobs.size() == 1) { 092 Blob blob = blobs.get(0); 093 String mimeType = blob.getMimeType(); 094 if (mimeType != null && mimeType.contains(LazyRendition.ERROR_MARKER)) { 095 ts.remove(key); 096 } else { 097 ts.release(key); 098 } 099 } else { 100 ts.release(key); 101 } 102 } else { 103 Work work = getRenditionWork(key, doc, def); 104 String workId = work.getId(); 105 WorkManager wm = Framework.getService(WorkManager.class); 106 if (wm.find(workId, null) == null) { 107 wm.schedule(work, Scheduling.IF_NOT_SCHEDULED); 108 } 109 } 110 } 111 112 return blobs; 113 } 114 115 @Override 116 public String getVariant(DocumentModel doc, RenditionDefinition definition) { 117 return AutomationRenderer.getVariant(doc, definition); 118 } 119 120 protected String buildRenditionKey(DocumentModel doc, RenditionDefinition def) { 121 122 StringBuffer sb = new StringBuffer(doc.getId()); 123 sb.append("::"); 124 String modificationDatePropertyName = def.getSourceDocumentModificationDatePropertyName(); 125 Calendar modif = (Calendar) doc.getPropertyValue(modificationDatePropertyName); 126 if (modif != null) { 127 long millis = modif.getTimeInMillis(); 128 // the date may have been rounded by the storage layer, normalize it to the second 129 millis -= millis % 1000; 130 sb.append(millis); 131 sb.append("::"); 132 } 133 String variant = getVariant(doc, def); 134 if (variant != null) { 135 sb.append(variant); 136 sb.append("::"); 137 } 138 sb.append(def.getName()); 139 140 return getDigest(sb.toString()); 141 } 142 143 protected String getDigest(String key) { 144 MessageDigest digest; 145 try { 146 digest = MessageDigest.getInstance("MD5"); 147 } catch (NoSuchAlgorithmException e) { 148 return key; 149 } 150 byte[] buf = digest.digest(key.getBytes()); 151 return toHexString(buf); 152 } 153 154 private static final char[] HEX_DIGITS = "0123456789abcdef".toCharArray(); 155 156 protected String toHexString(byte[] data) { 157 StringBuilder buf = new StringBuilder(2 * data.length); 158 for (byte b : data) { 159 buf.append(HEX_DIGITS[(0xF0 & b) >> 4]); 160 buf.append(HEX_DIGITS[0x0F & b]); 161 } 162 return buf.toString(); 163 } 164 165 /** 166 * Return the {@link Work} that will compute the {@link Rendition}. {@link AbstractRenditionBuilderWork} can be used 167 * as a base class 168 * 169 * @param key the key used to rendition 170 * @param doc the target {@link DocumentModel} 171 * @param def the {@link RenditionDefinition} 172 * @return 173 */ 174 protected abstract Work getRenditionWork(final String key, final DocumentModel doc, final RenditionDefinition def); 175 176}