使用Elasticsearch 7.9.1实现对word，pdf，txt文件的全文内容检索

1.安装插件

#预处理
./bin/elasticsearch-plugin install ingest-attachment
#分词
./bin/elasticsearch-plugin install https://github.com/medcl/elasticsearch-analysis-ik/releases/download/...这里找你的版本

2.定义文本抽取管道

PUT /_ingest/pipeline/attachment
{
    "description": "Extract attachment information",
    "processors": [
        {
            "attachment": {
                "field": "content",
                "ignore_missing": true
            }
        },
        {
            "remove": {
                "field": "content"
            }
        }
    ]
}

在attachment中指定要过滤的字段为content，所以写入Elasticsearch时需要将文档内容放在content字段

3.建立文档结构映射

PUT /docwrite
{
  "mappings": {
    "properties": {
      "id":{
        "typ