Blog System | Note-6

Blog System | Note-5

@2018年8月1日 14:43:38 @Knowledge From Imooc

####

搜索功能

使用Elasticsearchs实现全文检索

应用@

// 文档类型的EsBlog实体
@Document(indexName = "blog",type = "blog")
public class EsBlog implements Serializable{
    @Id
	private String id;

	// Blog实体的ID
	@Field(index = FieldIndex.not_analyzed)
	private Long blogId;
	private String title;
	private String summary;
	private String content;
	// 不使用全文检索字段
	@Field(index = FieldIndex.not_analyzed)
	private String username;
	...
	private String tags;
}

// EsBlogRepository
public interface EsBlogRepository extends ElasticsearchRepository<EsBlog,String> {
    // 模糊搜索查询
	Page<EsBlog> findDistinctEsBlogByTitleContainingOrSummaryContainingOrContentContainingOrTagsContaining(String title,String summary,String content,String tags,Pageable pageable);
}

// EsBlogService
public interface EsBlogService {
	// 最新博客列表
	Page<EsBlog> listNewestEsBlogs(String keyword, Pageable pageable);
	...
}

// Impl
@Override
public List<TagVO> listTop30Tags() {
    List<TagVO> list = new ArrayList<>();
    // given
    SearchQuery searchQuery = new NativeSearchQueryBuilder()
        .withQuery(matchAllQuery())
        .withSearchType(SearchType.QUERY_THEN_FETCH)
        .withIndices("blog").withTypes("blog")
        .addAggregation(terms("tags").field("tags").order(Terms.Order.count(false)).size(30))
        .build();
    // when
    Aggregations aggregations = elasticsearchTemplate.query(searchQuery, new ResultsExtractor<Aggregations>() {
        @Override
        public Aggregations extract(SearchResponse response) {
            return response.getAggregations();
        }
    });
    
    StringTerms modelTerms = (StringTerms)aggregations.asMap().get("tags");
    Iterator<Terms.Bucket> modelBucketIt = modelTerms.getBuckets().iterator();
    while (modelBucketIt.hasNext()){
        Terms.Bucket actiontypeBucket = modelBucketIt.next();
        list.add(new TagVO(actiontypeBucket.getKey().toString(),actiontypeBucket.getDocCount()));
    }
    return list;
}

// BlogController
@Controller
@RequestMapping("/blogs")
public class BlogController {
	@Autowired
	private EsBlogService esBlogService;

	/**
	 * 博客列表
	 */
	@GetMapping
	public String listBlogs(@RequestParam(value = "order", required = false, defaultValue = "new") String order,
							@RequestParam(value = "keyword", required = false, defaultValue = "") String keyword,
							@RequestParam(value = "async", required = false) boolean async,
							@RequestParam(value = "pageIndex", required = false, defaultValue = "0") int pageIndex,
							@RequestParam(value = "pageSize", required = false, defaultValue = "10") int pageSize,
							Model model) {
		Page<EsBlog> page = null;
		List<EsBlog> list = null;
		// 系统初始化时，没有博客数据
		boolean isEmpty = true;
		try {
			// 热门查询
			if (order.equals("hot")) {
				...
			} else if (order.equals("new")) {
				...
			}
			isEmpty = false;
		} catch (Exception e) {
		...
		}
		// 所在页面数据列表
		list = page.getContent();
		model.addAttribute("order", order);
		...
		// 首次访问页面才加载
		if (!async && !isEmpty) {
			List<EsBlog> newest = esBlogService.listTop5NewestEsBlogs();
			model.addAttribute("newest", newest);
			...
		}
		return (async == true ? "/index :: #mainContainerRepleace" : "/index");
	}
}