ElasticSearch簡介
ElasticSearch 是一個開源的搜索引擎，建立在一個全文搜索引擎庫 Apache Lucene? 基礎之上， Lucene 可以說是當下最先進、高性能、全功能的搜索引擎庫，無論是開源還是私有，
但是 Lucene 僅僅只是一個庫，為了充分發揮其功能，你需要使用 Java 并將 Lucene 直接集成到應用程式中， 更糟糕的是，您可能需要獲得資訊檢索學位才能了解其作業原理，Lucene 非常 復雜，
ElasticSearch 也是使用 Java 撰寫的，它的內部使用 Lucene 做索引與搜索，但是它的目的是使全文檢索變得簡單， 通過隱藏 Lucene 的復雜性，取而代之的提供一套簡單一致的 RESTful API，
然而，Elasticsearch 不僅僅是 Lucene，并且也不僅僅只是一個全文搜索引擎， 它可以被下面這樣準確的形容：
● 一個分布式的實時檔案存盤，每個欄位 可以被索引與搜索
● 一個分布式實時分析搜索引擎
● 能勝任上百個服務節點的擴展，并支持 PB 級別的結構化或者非結構化資料
官方客戶端在Java、.NET、PHP、Python、Ruby、Nodejs和許多其他語言中都是可用的，根據 DB-Engines 的排名顯示，ElasticSearch 是最受歡迎的企業搜索引擎，其次是Apache Solr，也是基于Lucene，
ElasticSearch不支持的場景：
1、 不支持事務
2、 不支持多表關聯查詢業務
3、不適合頻繁更新的業務場景， 讀寫有一定延時，寫入的資料，最快1s能被檢索到
默認情況下每個分片會每秒自動重繪一次，也就是說檔案從Index請求到對外可見能夠被搜到，最少要1秒鐘，網路和CPU再快也不行，這么做是Lucene為了提高寫操作的吞吐量而做出的延遲犧牲，當然這個設定是可以手動調整的，但是并不建議你去動它，會極大地影響搜索性能，重繪頻率太高也會導致集群陷入癱瘓，不同的應用對實時性的定義并不一樣，這取決于需求，
開始ElasticSearch之旅
1.創建 ASP.NET Core Web API 專案
創建net Core專案，將其命名為：ElasticSearchDemo，創建專案后，通過NuGet庫引入Nest包
2.添加物體模型
將 ES.Models目錄添加到專案根目錄下
使用以下代碼將 FamousPoemsModel類添加到 ES.Models 目錄
using System; namespace ES.Models { /// <summary> /// /// </summary> public class FamousPoemsModel { /// <summary> /// /// </summary> public FamousPoemsModel() { } /// <summary> /// /// </summary> public string Id { get; set; } /// <summary> /// 作者 /// </summary> [Nest.Keyword] public string vcAuthor { get; set; } /// <summary> /// 內容 /// </summary> [Nest.Keyword] public string vcContent { get; set; } /// <summary> /// 標題 /// </summary> [Nest.Keyword] public string vcTitle { get; set; } /// <summary> /// 創建時間 /// </summary> public DateTime dtCreateTime { get; set; } /// <summary> /// 更新時間 /// </summary> public DateTime dtUpdateTime { get; set; } } }
3.添加配置模型
appsettings.json 添加以下ElasticSearch配置
{ "Logging": { "LogLevel": { "Default": "Information", "Microsoft": "Warning", "Microsoft.Hosting.Lifetime": "Information" } }, "AllowedHosts": "*", "ElasticSearch": { "Uri": "http://es-cn-zvp2asu64001ta726.public.elasticsearch.aliyuncs.com:9200", "UserName": "elastic", "Password": "es123456@" } }
4.創建ES.Business目錄，在目錄下創建ElasticSearch、IService、Service目錄，廢話不多說，直接上代碼
using ES.Business.IService; using ES.Core; using ES.Models; using Nest; using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Threading.Tasks; namespace ES.Business.Service { /// <summary> /// /// </summary> public class FamousPoemsService : IFamousPoemsService, ITransientDependency { /// <summary> /// /// </summary> private readonly IEsUpdateService _updateService; /// <summary> /// /// </summary> private readonly IEsClientService _clientService; /// <summary> /// /// </summary> private readonly IEsIndexService _indexService; /// <summary> /// /// </summary> /// <param name="updateService"></param> /// <param name="clientService"></param> /// <param name="indexService"></param> public FamousPoemsService(IEsUpdateService updateService, IEsClientService clientService, IEsIndexService indexService) { _updateService = updateService; _clientService = clientService; _indexService = indexService; } /// <summary> /// 洗掉 /// </summary> /// <param name="Id"></param> /// <returns></returns> public async Task<long> DeleteAsync(string Id) { var mustFilters = new List<Func<QueryContainerDescriptor<FamousPoemsModel>, QueryContainer>>(); mustFilters.Add(t => t.Match(m => m.Field(f => f.Id).Query(Id))); var result = await _clientService.Client.DeleteByQueryAsync<FamousPoemsModel>(x => x.Index("famouspoemsmodel") .Query(q => q.Bool(b => b.Must(mustFilters)))); return result.Deleted; } /// <summary> /// 根據相關條件獲取分頁資料 /// </summary> /// <param name="dto"></param> /// <returns></returns> public async Task<PageModel<FamousPoemsModel>> GetPageAsync(ParameterModel dto) { PageModel<FamousPoemsModel> pageModel = new PageModel<FamousPoemsModel>(); var mustFilters = new List<Func<QueryContainerDescriptor<FamousPoemsModel>, QueryContainer>>(); if (!string.IsNullOrEmpty(dto.vcTitle)) { mustFilters.Add(t => t.Match(m => m.Field(f => f.vcTitle).Query(dto.vcTitle))); } if (dto.authors.Count() > 0) { mustFilters.Add(t => t.Terms(m => m.Field(f => f.vcAuthor).Terms(dto.authors.ToArray()))); } var total = await _clientService.Client.CountAsync<FamousPoemsModel>(x => x.Index("famouspoemsmodel") .Query(q => q.Bool(b => b.Must(mustFilters)))); if (total.Count == 0) { return pageModel; } pageModel.nDataCount = Convert.ToInt32(total.Count); pageModel.nPageCount = (int)Math.Ceiling((double)pageModel.nDataCount / dto.nPageSize); dto.nPageIndex = ((dto.nPageIndex < 1 ? 1 : dto.nPageIndex) - 1) * dto.nPageSize; var data = https://www.cnblogs.com/xiaoguli/archive/2021/08/26/await _clientService.Client.SearchAsync<FamousPoemsModel>(x => x.Index("famouspoemsmodel") .Query(q => q.Bool(b => b.Must(mustFilters))).Sort(s => s.Ascending(d => d.dtCreateTime)).From(dto.nPageIndex).Size(dto.nPageSize)); pageModel.data = (List<FamousPoemsModel>)data.Documents; return pageModel; } /// <summary> /// 新增資料 /// </summary> /// <param name="poems"></param> /// <returns></returns> public async Task<bool> InsertAsync(FamousPoemsModel poems) { return await _indexService.InsertAsync(poems); } /// <summary> /// 新增批量資料 /// </summary> /// <param name="poems"></param> /// <returns></returns> public async Task<bool> InsertRangeAsync(List<FamousPoemsModel> poems) { return await _indexService.InsertRangeAsync(poems); } /// <summary> /// 通過主鍵區域更新資料 /// </summary> /// <param name="nId"></param> /// <param name="vcTitle"></param> /// <returns></returns> public async Task<bool> UpdateAsync(string nId, string vcTitle) { FamousPoemsModel dto = new FamousPoemsModel(); dto.vcTitle = vcTitle; dto.dtUpdateTime = DateTime.Now; var result = _updateService.Update<FamousPoemsModel>(nId, dto); return result.IsValid; } /// <summary> /// 通過條件批量區域更新某個欄位資料 /// </summary> /// <returns></returns> public async Task<bool> UpdateByAuthorAsync(string vcAuthor) { var mustFilters = new List<Func<QueryContainerDescriptor<FamousPoemsModel>, QueryContainer>>(); mustFilters.Add(t => t.Match(m => m.Field(f => f.vcAuthor).Query(vcAuthor))); var result = await _clientService.Client.UpdateByQueryAsync<FamousPoemsModel>(q => q.Index("famouspoemsmodel") .Query(q => q.Bool(t => t.Must(mustFilters))) .Script(script => script.Source("ctx._source.dtUpdateTime=" + DateTime.Now + ";"))); return result.IsValid; } } }
5.將以下代碼添加到 Startup.ConfigureServices
#region ES配置 services.AddEsService(options => { options.Urls = Configuration["ElasticSearch:Uri"]; options.UserName = Configuration["ElasticSearch:UserName"]; options.Password = Configuration["ElasticSearch:Password"]; }); #endregion
6.添加控制器
using System; using System.Collections.Generic; using System.Linq; using System.Threading.Tasks; using ES.Business.IService; using ES.Models; using ES.Util; using Microsoft.AspNetCore.Http; using Microsoft.AspNetCore.Mvc; using Newtonsoft.Json; namespace ES.Web.Controllers { /// <summary> /// 屬性注入 /// </summary> public class PoemsController : ControllerBase { /// <summary> /// /// </summary> public IFamousPoemsService famousPoemsService { get; set; } /// <summary> /// 插入單條資料 /// </summary> /// <param name="poems"></param> /// <returns></returns> [HttpPost("Poems/InsertAsync")] public async Task<IActionResult> InsertAsync([FromBody]FamousPoemsModel poems) { return Content(JsonConvert.SerializeObject(await famousPoemsService.InsertAsync(poems))); } /// <summary> /// 批量插入資料 /// </summary> /// <param name="poems"></param> /// <returns></returns> [HttpPost("Poems/InsertRangeAsync")] public async Task<ActionResult> InsertRangeAsync([FromBody]List<FamousPoemsModel> poems) { return Content(JsonConvert.SerializeObject(await famousPoemsService.InsertRangeAsync(poems))); } /// <summary> /// /// </summary> /// <param name="Id"></param> /// <returns></returns> [HttpPost("Poems/DeleteAsync")] public async Task<ActionResult> DeleteAsync(string Id) { return Content(JsonConvert.SerializeObject(await famousPoemsService.DeleteAsync(Id))); } /// <summary> /// 更新 /// </summary> /// <param name="Id"></param> /// <param name="vcTitle"></param> /// <returns></returns> [HttpPost("Poems/UpdateAsync")] public async Task<ActionResult> UpdateAsync(string Id, string vcTitle) { return Content(JsonConvert.SerializeObject(await famousPoemsService.UpdateAsync(Id, vcTitle))); } /// <summary> /// 批量更新 /// </summary> /// <param name="vcAuthor"></param> /// <returns></returns> [HttpPost("Poems/UpdateByAuthorAsync")] public async Task<ActionResult> UpdateByAuthorAsync(string vcAuthor) { return Content(JsonConvert.SerializeObject(await famousPoemsService.UpdateByAuthorAsync(vcAuthor))); } /// <summary> /// 根據相關條件獲取分頁資料 /// </summary> /// <param name="dto"></param> /// <returns></returns> [ProducesResponseType(typeof(FamousPoemsModel), 200)] [HttpPost("Poems/GetPageAsync")] public async Task<ActionResult> GetPageAsync([FromBody]ParameterModel dto) { return Content(JsonConvert.SerializeObject(await famousPoemsService.GetPageAsync(dto))); } } }
本示例代碼gitee地址：https://gitee.com/fan_zhongtuan/elasticsearchdemo.git
阿里云ElasticSearch新用戶0員免費試用地址：https://www.aliyun.com/product/bigdata/elasticsearch
Elasticsearch官方權威檔案：https://www.elastic.co/guide/cn/elasticsearch/guide/current/foreword_id.html
轉載請註明出處，本文鏈接：https://www.uj5u.com/net/295804.html
標籤：.NET技术
下一篇：SuperSocket 簡單示例