/*
* Copyright 2011-2016 the original author or authors.
*
* Licensed 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.springframework.data.mongodb.crossstore;
import javax.persistence.EntityManagerFactory;
import org.bson.Document;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.dao.DataAccessException;
import org.springframework.dao.DataAccessResourceFailureException;
import org.springframework.dao.DataIntegrityViolationException;
import org.springframework.data.crossstore.ChangeSet;
import org.springframework.data.crossstore.ChangeSetBacked;
import org.springframework.data.crossstore.ChangeSetPersister;
import org.springframework.data.mongodb.core.CollectionCallback;
import org.springframework.data.mongodb.core.MongoTemplate;
import org.springframework.util.ClassUtils;
import com.mongodb.MongoException;
import com.mongodb.client.MongoCollection;
import com.mongodb.client.model.Filters;
import com.mongodb.client.result.DeleteResult;
/**
* @author Thomas Risberg
* @author Oliver Gierke
* @author Alex Vengrovsk
* @author Mark Paluch
*/
public class MongoChangeSetPersister implements ChangeSetPersister<Object> {
private static final String ENTITY_CLASS = "_entity_class";
private static final String ENTITY_ID = "_entity_id";
private static final String ENTITY_FIELD_NAME = "_entity_field_name";
private static final String ENTITY_FIELD_CLASS = "_entity_field_class";
private final Logger log = LoggerFactory.getLogger(getClass());
private MongoTemplate mongoTemplate;
private EntityManagerFactory entityManagerFactory;
public void setMongoTemplate(MongoTemplate mongoTemplate) {
this.mongoTemplate = mongoTemplate;
}
public void setEntityManagerFactory(EntityManagerFactory entityManagerFactory) {
this.entityManagerFactory = entityManagerFactory;
}
/*
* (non-Javadoc)
* @see org.springframework.data.crossstore.ChangeSetPersister#getPersistentState(java.lang.Class, java.lang.Object, org.springframework.data.crossstore.ChangeSet)
*/
public void getPersistentState(Class<? extends ChangeSetBacked> entityClass, Object id, final ChangeSet changeSet)
throws DataAccessException, NotFoundException {
if (id == null) {
log.debug("Unable to load MongoDB data for null id");
return;
}
String collName = getCollectionNameForEntity(entityClass);
final Document dbk = new Document();
dbk.put(ENTITY_ID, id);
dbk.put(ENTITY_CLASS, entityClass.getName());
if (log.isDebugEnabled()) {
log.debug("Loading MongoDB data for {}", dbk);
}
mongoTemplate.execute(collName, new CollectionCallback<Object>() {
public Object doInCollection(MongoCollection<Document> collection) throws MongoException, DataAccessException {
for (Document dbo : collection.find(dbk)) {
String key = (String) dbo.get(ENTITY_FIELD_NAME);
if (log.isDebugEnabled()) {
log.debug("Processing key: {}", key);
}
if (!changeSet.getValues().containsKey(key)) {
String className = (String) dbo.get(ENTITY_FIELD_CLASS);
if (className == null) {
throw new DataIntegrityViolationException(
"Unble to convert property " + key + ": Invalid metadata, " + ENTITY_FIELD_CLASS + " not available");
}
Class<?> clazz = ClassUtils.resolveClassName(className, ClassUtils.getDefaultClassLoader());
Object value = mongoTemplate.getConverter().read(clazz, dbo);
if (log.isDebugEnabled()) {
log.debug("Adding to ChangeSet: {}", key);
}
changeSet.set(key, value);
}
}
return null;
}
});
}
/*
* (non-Javadoc)
* @see org.springframework.data.crossstore.ChangeSetPersister#getPersistentId(org.springframework.data.crossstore.ChangeSetBacked, org.springframework.data.crossstore.ChangeSet)
*/
public Object getPersistentId(ChangeSetBacked entity, ChangeSet cs) throws DataAccessException {
if (log.isDebugEnabled()) {
log.debug("getPersistentId called on {}", entity);
}
if (entityManagerFactory == null) {
throw new DataAccessResourceFailureException("EntityManagerFactory cannot be null");
}
return entityManagerFactory.getPersistenceUnitUtil().getIdentifier(entity);
}
/*
* (non-Javadoc)
* @see org.springframework.data.crossstore.ChangeSetPersister#persistState(org.springframework.data.crossstore.ChangeSetBacked, org.springframework.data.crossstore.ChangeSet)
*/
public Object persistState(ChangeSetBacked entity, ChangeSet cs) throws DataAccessException {
if (cs == null) {
log.debug("Flush: changeset was null, nothing to flush.");
return 0L;
}
if (log.isDebugEnabled()) {
log.debug("Flush: changeset: {}", cs.getValues());
}
String collName = getCollectionNameForEntity(entity.getClass());
if (mongoTemplate.getCollection(collName) == null) {
mongoTemplate.createCollection(collName);
}
for (String key : cs.getValues().keySet()) {
if (key != null && !key.startsWith("_") && !key.equals(ChangeSetPersister.ID_KEY)) {
Object value = cs.getValues().get(key);
final Document dbQuery = new Document();
dbQuery.put(ENTITY_ID, getPersistentId(entity, cs));
dbQuery.put(ENTITY_CLASS, entity.getClass().getName());
dbQuery.put(ENTITY_FIELD_NAME, key);
final Document dbId = mongoTemplate.execute(collName, new CollectionCallback<Document>() {
public Document doInCollection(MongoCollection<Document> collection)
throws MongoException, DataAccessException {
Document id = collection.find(dbQuery).first();
return id;
}
});
if (value == null) {
if (log.isDebugEnabled()) {
log.debug("Flush: removing: {}", dbQuery);
}
mongoTemplate.execute(collName, new CollectionCallback<Object>() {
public Object doInCollection(MongoCollection<Document> collection)
throws MongoException, DataAccessException {
DeleteResult dr = collection.deleteMany(dbQuery);
return null;
}
});
} else {
final Document dbDoc = new Document();
dbDoc.putAll(dbQuery);
if (log.isDebugEnabled()) {
log.debug("Flush: saving: {}", dbQuery);
}
mongoTemplate.getConverter().write(value, dbDoc);
dbDoc.put(ENTITY_FIELD_CLASS, value.getClass().getName());
if (dbId != null) {
dbDoc.put("_id", dbId.get("_id"));
}
mongoTemplate.execute(collName, new CollectionCallback<Object>() {
public Object doInCollection(MongoCollection<Document> collection)
throws MongoException, DataAccessException {
if (dbId != null) {
collection.replaceOne(Filters.eq("_id", dbId.get("_id")), dbDoc);
} else {
if (dbDoc.containsKey("_id") && dbDoc.get("_id") == null) {
dbDoc.remove("_id");
}
collection.insertOne(dbDoc);
}
return null;
}
});
}
}
}
return 0L;
}
/**
* Returns the collection the given entity type shall be persisted to.
*
* @param entityClass must not be {@literal null}.
* @return
*/
private String getCollectionNameForEntity(Class<? extends ChangeSetBacked> entityClass) {
return mongoTemplate.getCollectionName(entityClass);
}
}