时间：2020-10-15 09:31:57 | 栏目：JAVA代码 | 点击：次
本文演示以Spark作为分析引擎,Cassandra作为数据存储,而使用Spring Boot来开发驱动程序的示例。
1.前置条件
创建keyspace
CREATE KEYSPACE hfcb WITH REPLICATION = { 'class' : 'SimpleStrategy', 'replication_factor' : 3 };
创建table
CREATE TABLE person ( id text PRIMARY KEY, first_name text, last_name text );
插入测试数据
insert into person (id,first_name,last_name) values('1','wang','yunfei');
insert into person (id,first_name,last_name) values('2','peng','chao');
insert into person (id,first_name,last_name) values('3','li','jian');
insert into person (id,first_name,last_name) values('4','zhang','jie');
insert into person (id,first_name,last_name) values('5','liang','wei');
2.spark-cassandra-connector安装
让Spark-1.5.1能够使用Cassandra作为数据存储，需要加上下面jar包的依赖(示例将包放置于 /opt/spark/managed-lib/ 目录，可任意):
cassandra-clientutil-3.0.2.jar cassandra-driver-core-3.1.4.jar guava-16.0.1.jar cassandra-thrift-3.0.2.jar joda-convert-1.2.jar joda-time-2.9.9.jar libthrift-0.9.1.jar spark-cassandra-connector_2.10-1.5.1.jar
在 /opt/spark/conf 目录下，新建 spark-env.sh 文件，输入下面内容
SPARK_CLASSPATH=/opt/spark/managed-lib/*
3.Spring Boot应用开发
添加 spark-cassandra-connector 和 spark 依赖
<dependency> <groupId>com.datastax.spark</groupId> <artifactId>spark-cassandra-connector_2.10</artifactId> <version>1.5.1</version> </dependency> <dependency> <groupId>org.apache.spark</groupId> <artifactId>spark-core_2.10</artifactId> <version>1.5.1</version> </dependency> <dependency> <groupId>org.apache.spark</groupId> <artifactId>spark-sql_2.10</artifactId> <version>1.5.1</version> </dependency>
在 application.yml 中配置 spark 与 cassandra 路径
spark.master: spark://master:7077 cassandra.host: 192.168.1.140 cassandra.keyspace: hfcb
此处特别说明 spark://master:7077 是域名形式而不是ip地址，可修改本地 hosts 文件将 master 与 ip 地址映射。
配置 SparkContext 和 CassandraSQLContext
@Configuration
public class SparkCassandraConfig {
@Value("${spark.master}")
String sparkMasterUrl;
@Value("${cassandra.host}")
String cassandraHost;
@Value("${cassandra.keyspace}")
String cassandraKeyspace;
@Bean
public JavaSparkContext javaSparkContext(){
SparkConf conf = new SparkConf(true)
.set("spark.cassandra.connection.host", cassandraHost)
// .set("spark.cassandra.auth.username", "cassandra")
// .set("spark.cassandra.auth.password", "cassandra")
.set("spark.submit.deployMode", "client");
JavaSparkContext context = new JavaSparkContext(sparkMasterUrl, "SparkDemo", conf);
return context;
}
@Bean
public CassandraSQLContext sqlContext(){
CassandraSQLContext cassandraSQLContext = new CassandraSQLContext(javaSparkContext().sc());
cassandraSQLContext.setKeyspace(cassandraKeyspace);
return cassandraSQLContext;
}
}
简单调用
@Repository
public class PersonRepository {
@Autowired
CassandraSQLContext cassandraSQLContext;
public Long countPerson(){
DataFrame people = cassandraSQLContext.sql("select * from person order by id");
return people.count();
}
}
启动即可如常规Spring Boot程序一样执行。
源码地址: https://github.com/wiselyman/spring-spark-cassandra.git
总结