ES全文检索支持拼音和繁简检索

1. 实现目标

ES检索时无论输入简体还是繁体都要能够被检索到，例如检索时输入“語法”或者“语法”，检索结果中无论是简体繁体都务必要被命中。

并且也要正确的高亮返回

2. 引入pinyin插件

拼音分词器（pinyin analyzer）通常需要自行引入，因为它不是 Elasticsearch 的默认分词器。可以使用 Elasticsearch 的插件来引入 pinyin 分词器，以便在索引中使用它。

2.1 编译 elasticsearch-analysis-pinyin 插件

选择与自己版本一致的版本，插件地址：
https://github.com/medcl/elasticsearch-analysis-pinyin/releases

elasticsearch-analysis-pinyin分词器目前没有下载即可使用的安装包，需要自己下载源码进行编译。可以在项目目录elasticsearch-analysis-pinyin\target\releases看到编译后的结果elasticsearch-analysis-pinyin-7.17.11.zip

2.2 安装拼音插件

然后在es的安装目录下plugins目录下新建pinyin目录，并将解压后的文件复制到该目录下

重启es，启动日志中已经加载了拼音插件

3. 引入ik分词器插件

GitHub下载地址：Releases · infinilabs/analysis-ik · GitHub

3.1 已有作者编译后的包文件

选择与所需es版本相同的ik分词器，下载已经打包后的.zip文件

3.2 只有源代码的版本

首先下载源码解压后使用idea打开，修改es版本与分词器版本相同

使用 mvn clean install 打包时报错：

[ERROR] Failed to execute goal org.apache.maven.plugins:maven-compiler-plugin:3.5.1:compile (default-compile) on project elasticsearch-analysis-ik: Compilation failure
[ERROR] /D:/PersonalProjects/analysis-ik-7.17.11/analysis-ik-7.17.11/src/main/java/org/elasticsearch/index/analysis/IkAnalyzerProvider.java:[13,9] 无法将类 org.elasticsearch.index.analysis.AbstractIndexAnalyzerProvider<T>中的构造器 
AbstractIndexAnalyzerProvider应用到给定类型;
[ERROR]   需要: org.elasticsearch.index.IndexSettings,java.lang.String,org.elasticsearch.common.settings.Settings
[ERROR]   找到: java.lang.String,org.elasticsearch.common.settings.Settings

修改代码报错部分：增加indexSetting参数到super入参的第一个位置

使用mvn clean install进行打包，注意我们所需的是/target/release目录下的.zip压缩包

3.3 安装ik分词插件

将下载或者编译后的.zip文件解压到es的安装目录下的plugins目录下，并重命名为ik

然后启动es，查看日志可发现已经加载的ik分词器

常规的最常用的使用方式就是，数据插入存储时用 ik_max_word模式分词，而检索时，用ik_smart模式分词，即：索引时最大化的将文章内容分词，搜索时更精确的搜索到想要的结果。

建立映射示例如下：在数据被索引时我们设置"analyzer": “ik_max_word”，在检索时指定"search_analyzer": “ik_smart”

4. 建立es索引

setting.json

{"aliases": {},"settings": {"index": {"refresh_interval": "3s","number_of_shards": "3","number_of_replicas": "1","max_inner_result_window": "10000","max_result_window": "20000","analysis": {"filter": {"pinyin_full_filter": {"keep_joined_full_pinyin": "true","lowercase": "true","keep_original": "false","keep_first_letter": "false","keep_separate_first_letter": "false","type": "pinyin","keep_none_chinese": "false","limit_first_letter_length": "50","keep_full_pinyin": "true"},"pinyin_simple_filter": {"keep_joined_full_pinyin": "true","lowercase": "true","none_chinese_pinyin_tokenize": "false","padding_char": " ","keep_original": "true","keep_first_letter": "true","keep_separate_first_letter": "false","type": "pinyin","keep_full_pinyin": "false"}},"analyzer": {"pinyinFullIndexAnalyzer": {"filter": ["asciifolding","lowercase","pinyin_full_filter"],"type": "custom","tokenizer": "ik_max_word"},"pinyinSimpleIndexAnalyzer": {"filter": ["pinyin_simple_filter","lowercase"],"type": "custom","tokenizer": "ik_max_word"},"ik_pinyin_analyzer": {"filter": ["asciifolding","lowercase","pinyin_full_filter","word_delimiter"],"type": "custom","tokenizer": "ik_smart"},"ikIndexAnalyzer": {"filter": ["asciifolding","lowercase","pinyin_full_filter","word_delimiter"],"type": "custom","tokenizer": "ik_max_word"}}}}},"mappings": {"dynamic": "false"}
}

mapping.json

{"properties": {"nickName": {"type": "text","analyzer": "ikIndexAnalyzer","search_analyzer": "ik_pinyin_analyzer","fields": {"full": {"type": "text","analyzer": "pinyinFullIndexAnalyzer"},"simple": {"type": "text","analyzer": "pinyinSimpleIndexAnalyzer"}}}}
}

mapping.json 文件定义了 Elasticsearch 索引中的字段映射和分析器设置:

1. analyzer：定义了在索引时使用的分析器。在搜索时会用这个分析器来处理查询字符串，使之与索引中的文本数据匹配。ikIndexAnalyzer 分析器使用了 ik_max_word 分词器（tokenizer），并应用了一系列过滤器（filter），包括 ASCII 折叠、小写转换、拼音处理和词分割。

2. search_analyzer：定义了在搜索时使用的分析器。ik_pinyin_analyzer分析器用于处理查询字符串，在进行搜索时与索引中的数据进行匹配。

3. fields：定义了为同一个字段创建不同的索引方式。在这个示例中，为 nickName 字段创建了两个额外的索引方式：full 和 simple。

   • full：使用了 pinyinFullIndexAnalyzer 分析器，它将 nickName 字段的文本进行全拼音分析，用于支持全拼音搜索。

   • simple：使用了 pinyinSimpleIndexAnalyzer 分析器，它将 nickName 字段的文本进行简拼音分析，用于支持简拼音搜索。

5.测试检索

新增测试数据

PUT /zzt_works/_doc/2
{"nickName":"語法講義"
} PUT /zzt_works/_doc/3
{"nickName":"语法讲义"
} 

中文简写查询

中文繁体查询

拼音全拼查询

拼音简拼查询

6. 繁简转换

如果需求只需要繁简转换，可使用以下设置和映射配置

index.json

{"aliases": {},"settings": {"index": {"refresh_interval": "3s","number_of_shards": "3","number_of_replicas": "1","max_inner_result_window": "10000","max_result_window": "20000","analysis": {"filter": {"pinyin_full_filter": {"keep_joined_full_pinyin": "true","lowercase": "true","keep_original": "false","keep_first_letter": "false","keep_separate_first_letter": "false","type": "pinyin","keep_none_chinese": "false","limit_first_letter_length": "50","keep_full_pinyin": "true"}},"analyzer": {"ik_pinyin_analyzer": {"filter": ["asciifolding","lowercase","pinyin_full_filter","word_delimiter"],"type": "custom","tokenizer": "ik_smart"},"ikIndexAnalyzer": {"filter": ["asciifolding","lowercase","pinyin_full_filter","word_delimiter"],"type": "custom","tokenizer": "ik_max_word"}}}}},"mappings": {"dynamic": "false"}
}

mapping.json

{"properties": {"nickName": {"type": "text","analyzer": "ikIndexAnalyzer","search_analyzer": "ik_pinyin_analyzer"}}
}