SpringBoot应用之分布式索引

SpringBoot应用系列文章

• SpringBoot应用之配置中心
• SpringBoot应用之分布式会话
• SpringBoot应用之分布式索引
• SpringBoot应用之分布式缓存
• SpringBoot应用之消息队列
• SpringBoot应用之ELK

序

本文主要讲怎么在SpringBoot中使用elasticsearch。elasticsearch呢，从其根源来讲，是索引服务，但是讲高端一点，就是分布式的实时文件存储、分布式的实时分析搜索引擎。

准备es

详见docker环境搭建elasticsearch这篇。

新建项目

application.properties

spring.data.elasticsearch.repositories.enabled=true
spring.data.elasticsearch.cluster-name=cn-out-of-box
spring.data.elasticsearch.cluster-nodes=192.168.99.100:9300

模型

@Document(indexName = "post", type = "post", shards = 1, replicas = 0)
public class Post {
    @Id
    private String id;

    private String title;

    private Double rating;

    @Field(type= FieldType.Nested)
    private List<Tag> tags;

    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 List<Tag> getTags() {
        return tags;
    }

    public void setTags(List<Tag> tags) {
        this.tags = tags;
    }

    public Double getRating() {
        return rating;
    }

    public void setRating(Double rating) {
        this.rating = rating;
    }
}

内嵌对象

public class Tag {
    private String id;
    private String name;

    public String getId() {
        return id;
    }

    public void setId(String id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }
}

repository

public interface PostRepository extends ElasticsearchRepository<Post, String> {

    Page<Post> findByTagsName(String name, Pageable pageable);

    List<Post> findByRatingBetween(Double beginning, Double end);

}

service层

@Service
public class PostService {

    @Autowired
    PostRepository postRepository;

    public Post save(Post post){
        postRepository.save(post);
        return post;
    }

    public Post findOne(String id) {
        return postRepository.findOne(id);
    }

    public Iterable<Post> findAll() {
        return postRepository.findAll();
    }

    public Page<Post> findByTagsName(String tagName, PageRequest pageRequest) {
        return postRepository.findByTagsName(tagName, pageRequest);
    }

    List<Post> findByRatingBetween(Double beginning, Double end){
        return postRepository.findByRatingBetween(beginning,end);
    }
}

Test

@RunWith(SpringJUnit4ClassRunner.class)
@SpringApplicationConfiguration(classes = EsdemoApplication.class)
public class EsdemoApplicationTests {

    @Autowired
    private PostService postService;

    @Autowired
    private ElasticsearchTemplate elasticsearchTemplate;

    @Before
    public void before() {
        elasticsearchTemplate.deleteIndex(Post.class);
        elasticsearchTemplate.createIndex(Post.class);
        elasticsearchTemplate.putMapping(Post.class);
        elasticsearchTemplate.refresh(Post.class, true);
    }

    @Test
    public void testSave() throws Exception {
        Tag tag = new Tag();
        tag.setId("1");
        tag.setName("tech");
        Tag tag2 = new Tag();
        tag2.setId("2");
        tag2.setName("elasticsearch");

        Post post = new Post();
        post.setId("1");
        post.setTitle("Bigining with spring boot application and elasticsearch");
        post.setRating(9.5);
        post.setTags(Arrays.asList(tag, tag2));
        postService.save(post);

        assertThat(post.getId(), notNullValue());

        Post post2 = new Post();
        post2.setId("2");
        post2.setTitle("Bigining with spring boot application");
        post2.setTags(Arrays.asList(tag));
        post2.setRating(7.5);
        postService.save(post2);
        assertThat(post2.getId(), notNullValue());
    }

    @Test //tag必须不是nested的
    public void testFindByTagsName() throws Exception {
        Tag tag = new Tag();
        tag.setId("1");
        tag.setName("tech");
        Tag tag2 = new Tag();
        tag2.setId("2");
        tag2.setName("elasticsearch");

        Post post = new Post();
        post.setId("1");
        post.setTitle("Bigining with spring boot application and elasticsearch");
        post.setRating(9.4);
        post.setTags(Arrays.asList(tag, tag2));
        postService.save(post);



        Post post2 = new Post();
        post2.setId("1");
        post2.setTitle("Bigining with spring boot application");
        post2.setTags(Arrays.asList(tag));
        post2.setRating(9.6);
        postService.save(post2);

        Page<Post> posts  = postService.findByTagsName("tech", new PageRequest(0,10));
        Page<Post> posts2  = postService.findByTagsName("tech", new PageRequest(0,10));
        Page<Post> posts3  = postService.findByTagsName("maz", new PageRequest(0,10));


        assertThat(posts.getTotalElements(), is(1L));
        assertThat(posts2.getTotalElements(), is(1L));
        assertThat(posts3.getTotalElements(), is(0L));
    }

}

save的截图

坑

• NoNodeAvailableException

org.elasticsearch.client.transport.NoNodeAvailableException: None of the configured nodes are available: []

应用中指定的cluster-name与集群中的cluster.name不一致的缘故。

参考

• First Step with Spring Boot and Elasticsearch
• Head first elastic search on java with spring boot and data features