Elastic App Search 後端連接

Elastic App Search 後端連接有兩種方式，一種是透過ELK的Elastic 去取得 Elastic App
的資料，第二種是直接用Java 打API的方式，去取得 Elastic App Search 的資料

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一、透過ELK查詢 Elastic App Search

1. 取得Elastic App Search 的 index，可以從Kibana取得所有的Elastic 列表，GET
   _cat/indices?v&index=*engine*

2. 回傳的結果

   health	status	index	uuid	pri	rep	docs.count	docs.deleted	store.size	pri.store.size
   green	open	.ent-search-engine-documents-hktv	N3UnO9mkRYS94RJnxUi23w	2	1	100	0	1.9mb	993.9kb

3. 會有多個 index，可以用docs.count 來判斷，Elastic App Search 的 index

4. 使用之前的遠端連結範例

   遠端連接

   ​​​​public static void main(String[] args ) throws IOException {
   
   ​​​​    //  建立連線端 這裡的是ELK的使用者名稱密碼與Host
   ​​​​    String username = "yourname";
   ​​​​    String password = "yourpassword";
   ​​​​    String host = "yourHost";
   
   ​​​​    int port = 9243;
   ​​​​    int nextPort = 9244;
   ​​​​    String protocol = "https";
   
   ​​​​    final CredentialsProvider credentialsProvider = new BasicCredentialsProvider();
   ​​​​    credentialsProvider.setCredentials(
   ​​​​            AuthScope.ANY,
   ​​​​            new UsernamePasswordCredentials(username, password));
   
   ​​​​    RestClientBuilder Builder = RestClient.builder(
   ​​​​            new HttpHost(host, port, protocol),
   ​​​​            new HttpHost(host, nextPort, protocol))
   ​​​​            .setHttpClientConfigCallback((h) -> h.setDefaultCredentialsProvider(credentialsProvider));
   
   
   ​​​​    try (RestHighLevelClient client = new RestHighLevelClient(Builder)) {
   ​​​​        //搜尋的Key與一般搜尋ELK不同，可能會因版本差異而改變
   ​​​​        QueryBuilder matchQueryBuilder = QueryBuilders.matchQuery("name_zh$string", "貓砂").fuzziness(Fuzziness.AUTO);;
   
   
   ​​​​        SearchSourceBuilder searchBuilder = SearchSourceBuilder.searchSource().query(matchQueryBuilder).size(50);
   
   ​​​​        //  index 的名稱
   ​​​​        SearchRequest request = new SearchRequest(".yourIndex").source(searchBuilder);
   
   ​​​​        SearchHits hits = client.search(request, RequestOptions.DEFAULT).getHits();
   
   
   ​​​​        //  逐筆取資料
   ​​​​        for(SearchHit hit : hits) {
   ​​​​            Map<String, Object> sourceAsMap = hit.getSourceAsMap();
   
   ​​​​            String name_zh = (String) sourceAsMap.get("name_zh$string");
   ​​​​            String selling_price = (String) sourceAsMap.get("selling_price$string");
   
   ​​​​            System.out.println(String.format("NameZH:%s selling_price:%s ",name_zh, selling_price));
   ​​​​        }
   ​​​​    }catch (IOException ignored) {}
   ​​​​}