使用NoSQL或MongoDB作为持久性存储的主要好处是,它们非常适合进行扩展。通过使用MongoDB,您可以将冷数据或历史数据直接以JSON的形式存储到持久层,而无需进行任何数据转换。MongoDB的持久性方法与前一节RDBMS非常相似。
image.png
上图显示了使用MongoDB作为持久化存储的概念体系结构。关于MongoDB: MongoDB是一个开源的无模式数据库。MongoDB是一个面向文档的数据库,以BSON或二进制JSON格式存储所有数据。这使MongoDB能够灵活地通过javascript访问它的功能,使特定类型的数据集成更容易、更快。MongoDB还通过共享集群的配置支持数据分片;这意味着可以垂直和水平无缝地扩展MongoDB。通常,MongoDB用于实时分析,在这种情况下,延迟很低,可用性非常高。为了完成MongoDB中缓存数据记录的持久性,我们将首先安装MongoDB并准备maven项目。如果已经在系统中安装和配置了MongoDB数据库,那么可以跳过第一步,从第4步继续。
Step 1:
从这里下载MongoDB发行版(https://www.mongodb.com/download-center?jmp=nav#community)。我将使用社区版和下载MacOS的发行版。
Step 2:
将发行版解压到操作系统中的某个位置,如下所示。
tar –xvf mongodb-osx-ssl-x86_64-4.0.3.tgz
创建本地文件目录/data/db
Step 3:
在命令行中使用以下命令运行MongoDB服务器。
./mongod --dbpath /data/db
MongoDB在27017端口启动并运行。
Step 4:
创建一个maven项目,并在pom.xml配置文件中添加所有的依赖项。
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.mycookcode.bigData.ignite</groupId>
<artifactId>ignite-persistence</artifactId>
<packaging>jar</packaging>
<version>1.0-SNAPSHOT</version>
<name>ignite-persistence</name>
<url>http://maven.apache.org</url>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<ignite.version>2.6.0</ignite.version>
<spring.version>5.1.1.RELEASE</spring.version>
</properties>
<dependencies>
<dependency>
<groupId>org.apache.ignite</groupId>
<artifactId>ignite-core</artifactId>
<version>${ignite.version}</version>
</dependency>
<dependency>
<groupId>org.apache.ignite</groupId>
<artifactId>ignite-spring</artifactId>
<version>${ignite.version}</version>
</dependency>
<dependency>
<groupId>org.apache.ignite</groupId>
<artifactId>ignite-indexing</artifactId>
<version>${ignite.version}</version>
</dependency>
<dependency>
<groupId>org.apache.ignite</groupId>
<artifactId>ignite-slf4j</artifactId>
<version>${ignite.version}</version>
</dependency>
<dependency>
<groupId>org.apache.ignite</groupId>
<artifactId>ignite-log4j</artifactId>
<version>${ignite.version}</version>
</dependency>
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-api</artifactId>
<version>1.7.25</version>
</dependency>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>3.8.1</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>postgresql</groupId>
<artifactId>postgresql</artifactId>
<version>9.1-901-1.jdbc4</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-core</artifactId>
<version>${spring.version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-aop</artifactId>
<version>${spring.version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-beans</artifactId>
<version>${spring.version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context</artifactId>
<version>${spring.version}</version>
</dependency>
<dependency>
<groupId>org.springframework.data</groupId>
<artifactId>spring-data-mongodb</artifactId>
<version>2.1.1.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework.data</groupId>
<artifactId>spring-data-jpa</artifactId>
<version>2.1.1.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-tx</artifactId>
<version>${spring.version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-expression</artifactId>
<version>${spring.version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-framework-bom</artifactId>
<version>${spring.version}</version>
<type>pom</type>
<scope>import</scope>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.3</version>
<configuration>
<source>1.8</source>
<target>1.8</target>
</configuration>
</plugin>
<plugin>
<groupId>com.jolira</groupId>
<artifactId>onejar-maven-plugin</artifactId>
<version>1.4.4</version>
<executions>
<execution>
<id>build-query</id>
<configuration>
<mainClass>com.mycookcode.bigData.ignite.App</mainClass>
<attachToBuild>true</attachToBuild>
<classifier>onejar</classifier>
<filename>cache-store-runnable.jar</filename>
</configuration>
<goals>
<goal>one-jar</goal>
</goals>
</execution>
</executions>
</plugin>
</plugins>
</build>
</project>
Step 5:
创建com.mycookcode.bigData.ignite.nosql.model.MongoPost类对应MongoDB中的数据模型。
package com.mycookcode.bigData.ignite.nosql.model;
import org.springframework.data.annotation.Id;
import org.springframework.data.mongodb.core.mapping.Document;
import java.time.LocalDate;
import java.util.Objects;
@Document
public class MongoPost {
@Id
private String id;
private String title;
private String description;
private LocalDate creationDate;
private String author;
public MongoPost() {
}
public MongoPost(String id, String title, String description, LocalDate creationDate, String author) {
this.id = id;
this.title = title;
this.description = description;
this.creationDate = creationDate;
this.author = author;
}
public String getId() {
return id;
}
public void setId(String id) {
this.id = id;
}
public String getTitle() {
return title;
}
public void setTitle(String title) {
this.title = title;
}
public String getDescription() {
return description;
}
public void setDescription(String description) {
this.description = description;
}
public LocalDate getCreationDate() {
return creationDate;
}
public void setCreationDate(LocalDate creationDate) {
this.creationDate = creationDate;
}
public String getAuthor() {
return author;
}
public void setAuthor(String author) {
this.author = author;
}
@Override
public boolean equals(Object o) {
if (this == o)
return true;
if (o == null || getClass() != o.getClass())
return false;
MongoPost post = (MongoPost)o;
return Objects.equals(id, post.id) &&
Objects.equals(title, post.title) &&
Objects.equals(description, post.description) &&
Objects.equals(creationDate, post.creationDate) &&
Objects.equals(author, post.author);
}
@Override
public int hashCode() {
return Objects.hash(id, title, description, creationDate, author);
}
@Override
public String toString() {
return "MongoPost{" +
"id='" + id + '\'' +
", title='" + title + '\'' +
", description='" + description + '\'' +
", creationDate=" + creationDate +
", author='" + author + '\'' +
'}';
}
}
Step 6:
我们将使用spring框架中的spring-data-MongoDB库来处理MongoDB。我们还创建了一个spring上下文文件mongo-context.xml来配置MongoDB工厂。
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:mongo="http://www.springframework.org/schema/data/mongo"
xmlns:context="http://www.springframework.org/schema/context"
xsi:schemaLocation="http://www.springframework.org/schema/data/mongo http://www.springframework.org/schema/data/mongo/spring-mongo.xsd
http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd">
<context:annotation-config />
<mongo:mongo-client id="mongo" host="localhost" port="27017"/>
<mongo:db-factory id="mongoDbFactory" dbname="test" mongo-ref="mongo" />
<bean id="mongoTemplate" class="org.springframework.data.mongodb.core.MongoTemplate">
<constructor-arg ref="mongoDbFactory"/>
</bean>
<mongo:repositories base-package="com.mycookcode.bigData.ignite.nosql" mongo-template-ref="mongoTemplate"/>
<bean class="org.springframework.dao.annotation.PersistenceExceptionTranslationPostProcessor"/>
</beans>
上面的XML文件指示Spring执行以下操作:
- 指定MongoDB主机和端口。
- 设置MongoDB工厂数据库名称是test。
- 转换MongoPost DTO为mongo Bson。
- 设置MongoDB模版工厂。
Step 7:
创建一个名为MongoDBStore的新Java类,它将扩展Ignite CacheStoreAdapter并实现LifecycleAware接口。
package com.mycookcode.bigData.ignite.nosql;
import com.mycookcode.bigData.ignite.nosql.model.MongoPost;
import org.apache.ignite.IgniteException;
import org.apache.ignite.cache.store.CacheStoreAdapter;
import org.apache.ignite.lifecycle.LifecycleAware;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.ConfigurableApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import org.springframework.data.mongodb.core.MongoOperations;
import javax.cache.Cache;
import javax.cache.integration.CacheLoaderException;
import javax.cache.integration.CacheWriterException;
public class MongoDBStore extends CacheStoreAdapter<String,MongoPost> implements LifecycleAware {
@Autowired
private PostRepository postRepository;
@Autowired
private MongoOperations mongoOperations;
private static Logger logger = LoggerFactory.getLogger(MongoDBStore.class);
@Override
public MongoPost load(String key) throws CacheLoaderException
{
logger.info(String.valueOf(postRepository));
return postRepository.findById(key).get();
}
@Override
public void write(Cache.Entry<? extends String,? extends MongoPost> entry) throws CacheWriterException
{
MongoPost post = entry.getValue();
logger.info(String.valueOf(postRepository));
postRepository.save(post);
}
@Override
public void delete(Object key) throws CacheWriterException
{
logger.info(String.valueOf(postRepository));
postRepository.deleteById((String) key);
}
@Override
public void start() throws IgniteException
{
ConfigurableApplicationContext context = new ClassPathXmlApplicationContext("mongo-context.xml");
postRepository = context.getBean(PostRepository.class);
logger.info(String.valueOf(postRepository));
mongoOperations = context.getBean(MongoOperations.class);
if (!mongoOperations.collectionExists(MongoPost.class))
mongoOperations.createCollection(MongoPost.class);
}
@Override
public void stop() throws IgniteException
{
}
}
上面的代码实现并覆写了三个CacheStore方法:load()、write()和delete()。在load()方法中,我们通过给定的键查找MongoDB中的文档,并返回MongoPost实例。Write()方法将单个缓存的数据记录保存到MongoDB test数据库中。Delete()方法通过给定的键从MongoDB删除bson文档。
Step 8:
为了存储并从MongoDB数据库加载数据,我们以编程方式配置Ignite cacheConfiguration。我们编写一个com.mycookcode.bigData.ignite.App类用于从缓存中存储和加载数据记录。
package com.mycookcode.bigData.ignite;
import com.mycookcode.bigData.ignite.jdbc.PostgresDBStore;
import com.mycookcode.bigData.ignite.jdbc.model.Post;
import com.mycookcode.bigData.ignite.nosql.MongoDBStore;
import com.mycookcode.bigData.ignite.nosql.model.MongoPost;
import org.apache.ignite.Ignite;
import org.apache.ignite.IgniteCache;
import org.apache.ignite.Ignition;
import org.apache.ignite.cache.CacheAtomicityMode;
import org.apache.ignite.configuration.CacheConfiguration;
import org.apache.ignite.configuration.IgniteConfiguration;
import org.apache.ignite.transactions.Transaction;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import javax.cache.Cache;
import javax.cache.configuration.FactoryBuilder;
import java.time.LocalDate;
import java.time.temporal.ChronoUnit;
import static org.apache.ignite.transactions.TransactionConcurrency.PESSIMISTIC;
import static org.apache.ignite.transactions.TransactionIsolation.REPEATABLE_READ;
public class App
{
private static final String POST_CACHE_NAME = App.class.getSimpleName() + "-post";
private static Logger LOGGER = LoggerFactory.getLogger(App.class);
private static final String POSTGRESQL = "postgresql";
private static final String MONGODB = "mongodb";
public static void main( String[] args ) throws Exception
{
if(args.length <= 0 ){
LOGGER.error("Usages! java -jar .\\target\\cache-store-runnable.jar postgresql|mongodb");
System.exit(0);
}
if(args[0].equalsIgnoreCase(POSTGRESQL)){
jdbcStoreExample();
} else if (args[0].equalsIgnoreCase(MONGODB)){
nosqlStore();
}
}
private static void nosqlStore() throws Exception
{
IgniteConfiguration cfg = new IgniteConfiguration();
CacheConfiguration configuration = new CacheConfiguration();
configuration.setName("mongoDynamicCache");
configuration.setAtomicityMode(CacheAtomicityMode.TRANSACTIONAL);
configuration.setCacheStoreFactory(FactoryBuilder.factoryOf(MongoDBStore.class));
configuration.setReadThrough(true);
configuration.setWriteThrough(true);
configuration.setWriteBehindEnabled(true);
log("Start. PersistenceStore example.");
cfg.setCacheConfiguration(configuration);
try (Ignite ignite = Ignition.start(cfg)){
int count = 10;
try(IgniteCache<String,MongoPost> igniteCache = ignite.getOrCreateCache(configuration))
{
try(Transaction tx = ignite.transactions().txStart(PESSIMISTIC, REPEATABLE_READ))
{
for(int i = 0;i <= count;i++)
{
igniteCache.put("_"+i,new MongoPost("_" + i, "title-" + i, "description-" + i, LocalDate.now().plus(i, ChronoUnit.DAYS), "author-" + i));
}
for (int i = 1; i < count; i += 2) {
igniteCache.clear("_" + i);
log("Clear every odd key: " + i);
}
for (long i = 1; i <= count; i++)
log("Local peek at [key=_" + i + ", val=" + igniteCache.localPeek("_" + i) + ']');
for (long i = 1; i <= count; i++)
log("Got [key=_" + i + ", val=" + igniteCache.get("_" + i) + ']');
tx.commit();
}
}
log("PersistenceStore example finished.");
ignite.destroyCache("mongoDynamicCache");
}
}
private static void jdbcStoreExample() throws Exception
{
//构建一个动态缓存,它分布在所有运行的节点上。
//也可以在xml配置文件中使用相同的配置
IgniteConfiguration cfg = new IgniteConfiguration();
CacheConfiguration configuration = new CacheConfiguration();
configuration.setName("dynamicCache");
configuration.setAtomicityMode(CacheAtomicityMode.TRANSACTIONAL);
configuration.setCacheStoreFactory(FactoryBuilder.factoryOf(PostgresDBStore.class));
configuration.setReadThrough(true);
configuration.setWriteThrough(true);
configuration.setWriteBehindEnabled(true);
log("Start. PersistenceStore example.");
cfg.setCacheConfiguration(configuration);
try(Ignite ignite = Ignition.start(cfg))
{
int count = 10;
try(IgniteCache<String,Post> igniteCache = ignite.getOrCreateCache(configuration))
{
try (Transaction tx = ignite.transactions().txStart(PESSIMISTIC,REPEATABLE_READ)){
for(int i = 1;i <= count;i++)
{
igniteCache.put("_"+i,new Post("_" + i, "title-" + i, "description-" + i, LocalDate.now().plus(i, ChronoUnit.DAYS),"author-" + i));
}
tx.commit();
for (int i = 1;i < count;i+=2)
{
igniteCache.clear("_"+i);
log("Clear every odd key: " + i);
}
for (long i = 1;i <= count;i++)
{
log("Local peek at [key=_" + i + ", val=" + igniteCache.localPeek("_" + i) + ']');
}
for (long i = 1;i <= count;i++)
{
log("Got [key=_" + i + ", val=" + igniteCache.get("_" + i) + ']');
}
tx.commit();
}
}
log("PersistenceStore example finished.");
//ignite.destroyCache("dynamicCache");
Thread.sleep(Integer.MAX_VALUE);
}
}
private static void log(String msg) {
LOGGER.info("\t" + msg);
}
}
首先创建Ignite CacheConfiguration实例,并将缓存名称设置为mongoDynamicCache。将原子性模式设置为事务性。然后将MongoDBStore设置为缓存工厂,并启用读写功能。
Step 9:
通过maven编译这个项目,并运行应用程序将一些条目从Ignite缓存存储到MongoDB中。
mvn clean install
使用以下命令运行应用程序。
java -jar ./target/cache-store-runnable.jar mongodb
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