ES的安装非常简单，基本上下载解压启动就可以，可参照官网：https://www.elastic.co/guide/cn/elasticsearch/guide/current/running-elasticsearch.html
启动过程中如果报错，参照下一篇文章解决

ES与客户端交互

有两种交互方式：

1、各种语言的SDK（包括Python也有）
2、HTTP接口

下面用Python代码演示ES的连接、新建文档、更新文档、查询文档等操作

import json
import requests
HOST = "172.16.91.3"
PORT = 9200
HEADERS = {"Content-Type": "application/json"}
BASE_URL = f"http://{HOST}:{PORT}"
# 获取所有文档数
def docs_count():
    # ?pretty是为了让返回结果格式化显示，该参数可不加
    url = BASE_URL + "/_count?pretty"
    data = {"query": {"match_all": {}}}
    response = requests.get(url, headers=HEADERS,
                            data=json.dumps(data, ensure_ascii=True))
    print(response.text)

输出结果

{
  "count" : 3,
  "_shards" : {
    "total" : 1,
    "successful" : 1,
    "skipped" : 0,
    "failed" : 0
  }
}

创建文档

# 创建/创建文档
def docs_put():
    # megacorp 是自定义的文档库（索引名称）
    # employee 是类型名称
    # 1        是文档ID（特定的雇员ID）
    url = BASE_URL + "/megacorp/employee/5"  # 如果文档已经存在，则更新，否则是创建
    data = {
        "first_name": "John",
        "last_name":  "Smith",
        "age":        25,
        "about":      "I love to go rock climbing",
        "interests": ["sports", "music"]
    }
    response = requests.post(url, headers=HEADERS,
                             data=json.dumps(data, ensure_ascii=True))
    print(response.text)

删除文档

# 删除文档
def docs_delete():
    url = BASE_URL + "/megacorp/employee/5"
    response = requests.delete(url, headers=HEADERS)
    print(response.text)

查询文档

# 查询文档
def docs_query():
    # ?pretty是为了让返回结果格式化显示，该参数可不加
    url = BASE_URL + "/megacorp/employee/1?pretty"
    response = requests.get(url, headers=HEADERS)
    print(response.text)

搜索所有文档

# 搜索所有雇员（文档）
def search_all():
    url = BASE_URL + "/megacorp/employee/_search?pretty"
    response = requests.get(url, headers=HEADERS)
    print(response.text)

全文搜索

# 全文检索：搜索所有喜欢攀岩（rock climbing）的员工
def search_full():
    url = BASE_URL + "/megacorp/employee/_search?pretty"
    data = {
        "query": {
            "match": {
                "about": "rock climbing"
            }
        }
    }
    response = requests.get(url, headers=HEADERS,
                            data=json.dumps(data, ensure_ascii=True))
    print(response.text)