SpringBoot实现ES简单搜索和推荐
1 ES7.6的高级客户端
// ES高级客户端
public RestHighLevelClient restHighLevelClient(){
RestClientBuilder restClientBuilder = RestClient.builder(
new HttpHost("127.0.0.1", 9200, "http"),
new HttpHost("192.168.128.11", 9200, "http"));
return new RestHighLevelClient(restClientBuilder);
}
2 ES简单搜索数据
public List<Map<String, Object>> query() {
String keyword = "中国";
// 1 建立搜索规则
// 建立多字段查询，字段名称是content和title
MultiMatchQueryBuilder multiMatchQueryBuilder = QueryBuilders.multiMatchQuery(keyword);
multiMatchQueryBuilder.field("content");
multiMatchQueryBuilder.field("title");
/*
// 单字段查询
MatchQueryBuilder matchQueryBuilder = QueryBuilders.matchQuery("title", keyword);
sourceBuilder.query(matchQueryBuilder);
*/
// Bool查询
BoolQueryBuilder boolQueryBuilder = QueryBuilders.boolQuery();
boolQueryBuilder.must(multiMatchQueryBuilder);
// 过滤器，过滤含有“绿色”的数据
boolQueryBuilder.filter(QueryBuilders.matchQuery("content", "绿色"));
// 过滤器，过滤日期在2016-01-01到2020-01-01之间的数据，注意日期格式必须是“yyyy-MM-dd HH:mm:ss”或“yyyy-MM-dd”，字段的type是date，format是yyyy-MM-dd，如果格式错误搜索出的数据有问题
boolQueryBuilder.filter(QueryBuilders.rangeQuery("date").gte("2016-01-01").lte("2020-01-01"));
// 2 建立查询
SearchSourceBuilder sourceBuilder = new SearchSourceBuilder();
sourceBuilder.query(boolQueryBuilder);
// 设置起始页
sourceBuilder.from(0);
// 设置一页的数据量，默认是10条数据
sourceBuilder.size(100);
// 设置超时
sourceBuilder.timeout(new TimeValue(6, TimeUnit.SECONDS));
// 设置高亮
HighlightBuilder highlightBuilder = new HighlightBuilder();
highlightBuilder.requireFieldMatch(false);
highlightBuilder.field("content");
highlightBuilder.field("title");
highlightBuilder.preTags("<em>");
highlightBuilder.postTags("</em>");
sourceBuilder.highlighter(highlightBuilder);
// 设置SearchRequest，可以指定多个索引，默认是所有索引
SearchRequest request = new SearchRequest("website", "article");
request.source(sourceBuilder);
// 获取返回值
List<Map<String, Object>> data = new ArrayList<>();
try {
SearchResponse response = this.restHighLevelClient.search(request, RequestOptions.DEFAULT);
for (SearchHit hit: response.getHits().getHits()) {
// 获取得SourceMap
Map<String, Object> sourceMap = hit.getSourceAsMap();
// 获取高亮
Map<String, HighlightField> highlightFields = hit.getHighlightFields();
HighlightField title = highlightFields.get("title");
StringBuilder highlightTitle = new StringBuilder();
if (title != null) {
Text[] fragment = title.fragments();
for (Text text : fragment) {
highlightTitle.append(text);
}
}
// Replace the title
if (highlightTitle.length() > 0) {
sourceMap.put("title", highlightTitle.toString());
}
HighlightField content = highlightFields.get("content");
StringBuilder highlightSummary = new StringBuilder();
if (content != null) {
Text[] fragment = content.fragments();
for (Text text : fragment) {
highlightSummary.append(text);
}
}
// 将highlightSummary替换sourceMap的content即可
if (highlightSummary.length() > 0) {
sourceMap.put("content", highlightSummary.toString());
}
// Add the list
data.add(sourceMap);
}
} catch (IOException e) {
e.printStackTrace();
}
return data;
}
3 CompletionSuggest推荐
// title的类型是"type": "completion"，index不能是true（索引功能关闭）
// 完整推荐， 例如：keyword=中国，则会推荐“中国经济不断发展，中国进入世贸组织”（title的整个字段的内容）
public Set<String> completionSuggestData(String keyword){
// 设置CompletionSuggestion
CompletionSuggestionBuilder completionSuggestion = SuggestBuilders.completionSuggestion("title").prefix(keyword).size(20);
SuggestBuilder suggestBuilder = new SuggestBuilder();
suggestBuilder.addSuggestion("suggest_user", completionSuggestion);
// 将completionSuggestion添加到searchSourceBuilder中
SearchSourceBuilder searchSourceBuilder = new SearchSourceBuilder();
// 设置超时时间
searchSourceBuilder.timeout(new TimeValue(2, TimeUnit.SECONDS));
searchSourceBuilder.suggest(suggestBuilder);
// 将searchSourceBuilder添加到searchRequest中
SearchRequest searchRequest = new SearchRequest("paper_db");
searchRequest.source(searchSourceBuilder);
// 存储suggest
HashSet<String> data = new HashSet<String>();
try {
// 读取suggest
SearchResponse searchResponse = this.restHighLevelClient.search(searchRequest, RequestOptions.DEFAULT);
Suggest suggest = searchResponse.getSuggest();
if(suggest != null){
CompletionSuggestion result = suggest.getSuggestion("suggest_user");
for ( CompletionSuggestion.Entry entrys : result.getEntries()) {
for(Suggest.Suggestion.Entry.Option option: entrys.getOptions()){
if(option != null){
// Remove special char and repeat data
data.add(option.getText().toString());
}
}
}
}
} catch (IOException e) {
e.printStackTrace();
}
return data;
}
4 TermSuggest推荐
// 推荐相似的词和短语
// 例如：keyword=中国人民，则会推荐“中国企业, 中国经济, 中国移动, 中国国际”（数据库里必须有相关的字段数据）
public Set<String> termSuggestData(String keyword){
// 建立 TermSuggestionBuilder
TermSuggestionBuilder termSuggestionBuilder = SuggestBuilders.termSuggestion("title").text(keyword).size(100);
SuggestBuilder suggestBuilder = new SuggestBuilder();
suggestBuilder.addSuggestion("suggest_user", termSuggestionBuilder);
// 建立SearchSourceBuilder，添加suggest
SearchSourceBuilder searchSourceBuilder = new SearchSourceBuilder();
searchSourceBuilder.timeout(new TimeValue(2, TimeUnit.SECONDS));
searchSourceBuilder.suggest(suggestBuilder);
// 将searchSourceBuilder添加到searchRequest中
SearchRequest searchRequest = new SearchRequest("paper_db");
searchRequest.source(searchSourceBuilder);
// 存储suggest
HashSet<String> data = new HashSet<String>();
try {
// 读取suggest
SearchResponse searchResponse = this.restHighLevelClient.search(searchRequest, RequestOptions.DEFAULT);
Suggest suggest = searchResponse.getSuggest();
if (suggest != null) {
TermSuggestion result = suggest.getSuggestion("suggest_user");
for (TermSuggestion.Entry entry : result.getEntries()) {
for (Suggest.Suggestion.Entry.Option option : entry.getOptions()) {
if (option != null) {
// Remove special char and repeat data
data.add(option.getText().toString());
}
}
}
}
} catch (IOException e) {
e.printStackTrace();
}
return data;
}