001    /*
002      GRANITE DATA SERVICES
003      Copyright (C) 2011 GRANITE DATA SERVICES S.A.S.
004    
005      This file is part of Granite Data Services.
006    
007      Granite Data Services is free software; you can redistribute it and/or modify
008      it under the terms of the GNU Library General Public License as published by
009      the Free Software Foundation; either version 2 of the License, or (at your
010      option) any later version.
011    
012      Granite Data Services is distributed in the hope that it will be useful, but
013      WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
014      FITNESS FOR A PARTICULAR PURPOSE. See the GNU Library General Public License
015      for more details.
016    
017      You should have received a copy of the GNU Library General Public License
018      along with this library; if not, see <http://www.gnu.org/licenses/>.
019    */
020    
021    package org.granite.tide.spring;
022    
023    import java.util.HashMap;
024    import java.util.Map;
025    
026    import org.aopalliance.intercept.MethodInterceptor;
027    import org.aopalliance.intercept.MethodInvocation;
028    import org.granite.gravity.Gravity;
029    import org.granite.logging.Logger;
030    import org.granite.tide.data.DataContext;
031    import org.granite.tide.data.DataEnabled;
032    import org.granite.tide.data.DataEnabled.PublishMode;
033    import org.granite.tide.data.DataUpdatePostprocessor;
034    import org.granite.tide.data.TideSynchronizationManager;
035    import org.granite.util.TypeUtil;
036    import org.springframework.beans.factory.annotation.Autowired;
037    import org.springframework.transaction.support.TransactionSynchronizationAdapter;
038    import org.springframework.transaction.support.TransactionSynchronizationManager;
039    
040    /**
041     * Spring AOP interceptor to handle publishing of data changes instead of relying on the default behaviour
042     * This can be used outside of a HTTP Granite context and inside the security/transaction context
043     * 
044     * Ensure that the order of the interceptor is correctly setup to use ON_COMMIT publish mode: this interceptor must be executed inside a transaction
045     *  
046     * @author William DRAI
047     */
048    public class TideDataPublishingInterceptor implements MethodInterceptor {
049            
050            private static final Logger log = Logger.getLogger(TideDataPublishingInterceptor.class);
051            
052            private Gravity gravity;
053            private DataUpdatePostprocessor dataUpdatePostprocessor;
054            
055            private Map<String, TideSynchronizationManager> syncsMap = new HashMap<String, TideSynchronizationManager>();
056            
057            public TideDataPublishingInterceptor() {
058                    try {
059                            syncsMap.put("org.springframework.orm.hibernate3.SessionHolder", TypeUtil.newInstance("org.granite.tide.spring.Hibernate3SynchronizationManager", TideSynchronizationManager.class));
060                    }
061                    catch (Throwable e) {
062                            // Hibernate 3 not present
063                    }
064                    try {
065                            syncsMap.put("org.springframework.orm.hibernate4.SessionHolder", TypeUtil.newInstance("org.granite.tide.spring.Hibernate4SynchronizationManager", TideSynchronizationManager.class));
066                    }
067                    catch (Throwable e) {
068                            // Hibernate 4 not present
069                    }
070                    try {
071                            syncsMap.put("org.springframework.orm.jpa.EntityManagerHolder", TypeUtil.newInstance("org.granite.tide.spring.JPASynchronizationManager", TideSynchronizationManager.class));
072                    }
073                    catch (Throwable e) {
074                            // JPA not present
075                    }
076            }
077            
078            
079            public void setGravity(Gravity gravity) {
080                    this.gravity = gravity;
081            }
082            
083            @Autowired(required=false)
084            public void setDataUpdatePostprocessor(DataUpdatePostprocessor dataUpdatePostprocessor) {
085                    this.dataUpdatePostprocessor = dataUpdatePostprocessor;
086            }
087            
088        public Object invoke(final MethodInvocation invocation) throws Throwable {
089            DataEnabled dataEnabled = invocation.getThis().getClass().getAnnotation(DataEnabled.class);
090            if (dataEnabled == null || !dataEnabled.useInterceptor())
091                    return invocation.proceed();
092            
093            boolean shouldRemoveContextAtEnd = DataContext.get() == null;
094            boolean shouldInitContext = shouldRemoveContextAtEnd || DataContext.isNull();
095            boolean onCommit = false;
096            
097            if (shouldInitContext) {
098                    DataContext.init(gravity, dataEnabled.topic(), dataEnabled.params(), dataEnabled.publish());
099                    if (dataUpdatePostprocessor != null)
100                            DataContext.get().setDataUpdatePostprocessor(dataUpdatePostprocessor);
101            }
102            
103            DataContext.observe();
104            try {
105                    if (dataEnabled.publish().equals(PublishMode.ON_COMMIT) && !TransactionSynchronizationManager.isCurrentTransactionReadOnly()) {
106                             if (TransactionSynchronizationManager.isSynchronizationActive()) {
107                                     boolean registered = false;
108                                     for (Object resource : TransactionSynchronizationManager.getResourceMap().values()) {
109                                             if (syncsMap.containsKey(resource.getClass().getName())) {
110                                                     registered = syncsMap.get(resource.getClass().getName()).registerSynchronization(resource, shouldRemoveContextAtEnd);
111                                                     break;
112                                             }
113                                     }
114                                     if (!registered)
115                                             TransactionSynchronizationManager.registerSynchronization(new DataPublishingTransactionSynchronization(shouldRemoveContextAtEnd));
116                                     else if (shouldRemoveContextAtEnd)
117                                                     TransactionSynchronizationManager.registerSynchronization(new DataContextCleanupTransactionSynchronization());
118                                     onCommit = true;
119                             }
120                             else {
121                                     log.error("Could not register synchronization for ON_COMMIT publish mode, check that the Spring PlatformTransactionManager supports it "
122                                                     + "and that the order of the TransactionInterceptor is lower than the order of TideDataPublishingInterceptor");
123                             }
124                    }
125                    
126                    Object ret = invocation.proceed();
127                    
128                    DataContext.publish(PublishMode.ON_SUCCESS);
129                    return ret;
130            }
131            finally {
132                    if (shouldRemoveContextAtEnd && !onCommit)
133                            DataContext.remove();
134            }
135        }
136        
137        private static class DataPublishingTransactionSynchronization extends TransactionSynchronizationAdapter {
138            
139            private boolean removeContext = false;
140            
141            public DataPublishingTransactionSynchronization(boolean removeContext) {
142                    this.removeContext = removeContext;
143            }
144    
145                    @Override
146                    public void beforeCommit(boolean readOnly) {
147                            if (!readOnly)
148                                    DataContext.publish(PublishMode.ON_COMMIT);
149                    }
150                    
151                    @Override
152                    public void beforeCompletion() {
153                            if (removeContext)
154                                    DataContext.remove();
155                    }
156                    
157                    @Override
158                    public void afterCompletion(int status) {
159                            if (removeContext)
160                                    DataContext.remove();
161                    }
162        }
163    
164        private static class DataContextCleanupTransactionSynchronization extends TransactionSynchronizationAdapter {
165            
166                    @Override
167                    public void afterCompletion(int status) {
168                            DataContext.remove();
169                    }
170        }
171    }