Elasticsearch 瞬间入门

把大象放进冰箱共有几步？

1. 打开冰箱门

2. 把大象放进去

3. 关上冰箱门

Elasticsearch 非常容易学习，分为3步：

1. 把数据放进去

2. 创建索引

3. 查数据

节选自《Netkiller Database 手札》

60.1. 安装 Elasticsearch

60.1.1. RPM 安装

代码语言：javascript复制

yum localinstall https://download.elastic.co/elasticsearch/release/org/elasticsearch/distribution/rpm/elasticsearch/2.3.4/elasticsearch-2.3.4.rpm

60.1.2. YUM 安装

代码语言：javascript复制

			rpm --import https://packages.elastic.co/GPG-KEY-elasticsearch

cat >> /etc/yum.repos.d/elasticsearch.repo <<EOF
[elasticsearch-2.x]
name=Elasticsearch repository for 2.x packages
baseurl=https://packages.elastic.co/elasticsearch/2.x/centos
gpgcheck=1
gpgkey=https://packages.elastic.co/GPG-KEY-elasticsearch
enabled=1
EOF

yum install elasticsearch

sudo /bin/systemctl daemon-reload
sudo /bin/systemctl enable elasticsearch.service

查看 RPM 包中所含文件

代码语言：javascript复制

[root@localhost ~]# rpm -ql elasticsearch-2.3.4-1.noarch 
/etc/elasticsearch
/etc/elasticsearch/elasticsearch.yml
/etc/elasticsearch/logging.yml
/etc/elasticsearch/scripts
/etc/init.d/elasticsearch
/etc/sysconfig/elasticsearch
/usr/lib/sysctl.d
/usr/lib/sysctl.d/elasticsearch.conf
/usr/lib/systemd/system/elasticsearch.service
/usr/lib/tmpfiles.d
/usr/lib/tmpfiles.d/elasticsearch.conf
/usr/share/elasticsearch/LICENSE.txt
/usr/share/elasticsearch/NOTICE.txt
/usr/share/elasticsearch/README.textile
/usr/share/elasticsearch/bin
/usr/share/elasticsearch/bin/elasticsearch
/usr/share/elasticsearch/bin/elasticsearch-systemd-pre-exec
/usr/share/elasticsearch/bin/elasticsearch.in.sh
/usr/share/elasticsearch/bin/plugin
/usr/share/elasticsearch/lib
/usr/share/elasticsearch/lib/HdrHistogram-2.1.6.jar
/usr/share/elasticsearch/lib/apache-log4j-extras-1.2.17.jar
/usr/share/elasticsearch/lib/commons-cli-1.3.1.jar
/usr/share/elasticsearch/lib/compiler-0.8.13.jar
/usr/share/elasticsearch/lib/compress-lzf-1.0.2.jar
/usr/share/elasticsearch/lib/elasticsearch-2.3.4.jar
/usr/share/elasticsearch/lib/guava-18.0.jar
/usr/share/elasticsearch/lib/hppc-0.7.1.jar
/usr/share/elasticsearch/lib/jackson-core-2.6.6.jar
/usr/share/elasticsearch/lib/jackson-dataformat-cbor-2.6.6.jar
/usr/share/elasticsearch/lib/jackson-dataformat-smile-2.6.6.jar
/usr/share/elasticsearch/lib/jackson-dataformat-yaml-2.6.6.jar
/usr/share/elasticsearch/lib/jna-4.1.0.jar
/usr/share/elasticsearch/lib/joda-convert-1.2.jar
/usr/share/elasticsearch/lib/joda-time-2.9.4.jar
/usr/share/elasticsearch/lib/jsr166e-1.1.0.jar
/usr/share/elasticsearch/lib/jts-1.13.jar
/usr/share/elasticsearch/lib/log4j-1.2.17.jar
/usr/share/elasticsearch/lib/lucene-analyzers-common-5.5.0.jar
/usr/share/elasticsearch/lib/lucene-backward-codecs-5.5.0.jar
/usr/share/elasticsearch/lib/lucene-core-5.5.0.jar
/usr/share/elasticsearch/lib/lucene-grouping-5.5.0.jar
/usr/share/elasticsearch/lib/lucene-highlighter-5.5.0.jar
/usr/share/elasticsearch/lib/lucene-join-5.5.0.jar
/usr/share/elasticsearch/lib/lucene-memory-5.5.0.jar
/usr/share/elasticsearch/lib/lucene-misc-5.5.0.jar
/usr/share/elasticsearch/lib/lucene-queries-5.5.0.jar
/usr/share/elasticsearch/lib/lucene-queryparser-5.5.0.jar
/usr/share/elasticsearch/lib/lucene-sandbox-5.5.0.jar
/usr/share/elasticsearch/lib/lucene-spatial-5.5.0.jar
/usr/share/elasticsearch/lib/lucene-spatial3d-5.5.0.jar
/usr/share/elasticsearch/lib/lucene-suggest-5.5.0.jar
/usr/share/elasticsearch/lib/netty-3.10.5.Final.jar
/usr/share/elasticsearch/lib/securesm-1.0.jar
/usr/share/elasticsearch/lib/snakeyaml-1.15.jar
/usr/share/elasticsearch/lib/spatial4j-0.5.jar
/usr/share/elasticsearch/lib/t-digest-3.0.jar
/usr/share/elasticsearch/modules
/usr/share/elasticsearch/modules/lang-expression
/usr/share/elasticsearch/modules/lang-expression/antlr4-runtime-4.5.1-1.jar
/usr/share/elasticsearch/modules/lang-expression/asm-5.0.4.jar
/usr/share/elasticsearch/modules/lang-expression/asm-commons-5.0.4.jar
/usr/share/elasticsearch/modules/lang-expression/lang-expression-2.3.4.jar
/usr/share/elasticsearch/modules/lang-expression/lucene-expressions-5.5.0.jar
/usr/share/elasticsearch/modules/lang-expression/plugin-descriptor.properties
/usr/share/elasticsearch/modules/lang-expression/plugin-security.policy
/usr/share/elasticsearch/modules/lang-groovy
/usr/share/elasticsearch/modules/lang-groovy/groovy-2.4.6-indy.jar
/usr/share/elasticsearch/modules/lang-groovy/lang-groovy-2.3.4.jar
/usr/share/elasticsearch/modules/lang-groovy/plugin-descriptor.properties
/usr/share/elasticsearch/modules/lang-groovy/plugin-security.policy
/usr/share/elasticsearch/modules/reindex
/usr/share/elasticsearch/modules/reindex/plugin-descriptor.properties
/usr/share/elasticsearch/modules/reindex/reindex-2.3.4.jar
/usr/share/elasticsearch/plugins
/var/lib/elasticsearch
/var/log/elasticsearch
/var/run/elasticsearch

60.1.3. 测试安装是否正常

启动

代码语言：javascript复制

/etc/init.d/elasticsearch start

链接测试

代码语言：javascript复制

[root@localhost ~]# curl -X GET http://localhost:9200/
{
  "name" : "Jack of Hearts",
  "cluster_name" : "elasticsearch",
  "version" : {
    "number" : "2.3.4",
    "build_hash" : "e455fd0c13dceca8dbbdbb1665d068ae55dabe3f",
    "build_timestamp" : "2016-06-30T11:24:31Z",
    "build_snapshot" : false,
    "lucene_version" : "5.5.0"
  },
  "tagline" : "You Know, for Search"
}

60.2. 文档API

60.2.1. 快速上手

文档通过 _index、_type、_id 元数据(metadata)，确定 URL 唯一

代码语言：javascript复制

			GET /<_index>/<_type>/<_id>

代码语言：javascript复制

# curl -XPUT 'http://localhost:9200/website/profile/1' -d '{
	"name" : "neo",
	"nickname" : "netkiller",
	"age" : "35",
	"message" : "Helloworld !!!"
}'

# curl -XGET 'http://localhost:9200/website/profile/1?pretty'
{
  "_index" : "website",
  "_type" : "profile",
  "_id" : "1",
  "_version" : 1,
  "found" : true,
  "_source" : {
    "name" : "neo",
    "nickname" : "netkiller",
    "age" : "35",
    "message" : "Helloworld !!!"
  }
}

# curl -XPUT 'http://localhost:9200/website/blog/1?pretty' -d '{
>   "title": "My first blog entry",
>   "text":  "Just trying this out...",
>   "date":  "2014/01/01"
> }'
{
  "_index" : "website",
  "_type" : "blog",
  "_id" : "1",
  "_version" : 1,
  "_shards" : {
    "total" : 2,
    "successful" : 1,
    "failed" : 0
  },
  "created" : true
}

后面会详细讲解 PUT与GET的使用方法以及相关参数

60.2.2. 写入 PUT/POST

通过 PUT 写入数据

代码语言：javascript复制

[root@localhost ~]# curl -XPUT 'http://localhost:9200/twitter/tweet/1' -d '{
>     "user" : "kimchy",
>     "post_date" : "2009-11-15T14:12:12",
>     "message" : "trying out Elasticsearch"
> }'
{"_index":"twitter","_type":"tweet","_id":"1","_version":1,"_shards":{"total":2,"successful":1,"failed":0},"created":true}

使用 UUID 替代 _id, 注意使用UUID 必须使用 POST方式提交，不能使用 PUT。

代码语言：javascript复制

curl -XPOST 'http://localhost:9200/website/news/?pretty' -d '{
  "title": "My first news entry",
  "text":  "Just trying this out..."
}'
{
  "_index" : "website",
  "_type" : "news1",
  "_id" : "AVY0RJrvJRTrBLpmYzBH",
  "_version" : 1,
  "_shards" : {
    "total" : 2,
    "successful" : 1,
    "failed" : 0
  },
  "created" : true
}

curl -XGET 'http://localhost:9200/website/news/AVY0RJrvJRTrBLpmYzBH?pretty'

提交后会输出 "_id" : "AVY0RJrvJRTrBLpmYzBH"，查询时将此放到放到URL中即可。

60.2.3. 获取 GET

通过 GET 读取数据

代码语言：javascript复制

[root@localhost ~]# curl -XGET 'http://localhost:9200/twitter/tweet/1'
{"_index":"twitter","_type":"tweet","_id":"1","_version":1,"found":true,"_source":{
    "user" : "kimchy",
    "post_date" : "2009-11-15T14:12:12",
    "message" : "trying out Elasticsearch"
}}

60.2.3.1. _source

只返回 _source 数据，去掉元数据

代码语言：javascript复制

# curl -XGET 'http://localhost:9200/website/news1/AVY0Q4SqdtH0Up0t-WB2/_source?pretty'
{
  "title" : "My first news entry",
  "text" : "Just trying this out..."
}

选择字段 _source=title，超过一个字段使用逗号分隔_source=title,text。

代码语言：javascript复制

				# curl -XGET 'http://localhost:9200/website/news1/AVY0Q4SqdtH0Up0t-WB2?_source=title&pretty'
{
  "_index" : "website",
  "_type" : "news1",
  "_id" : "AVY0Q4SqdtH0Up0t-WB2",
  "_version" : 1,
  "found" : true,
  "_source" : {
    "title" : "My first news entry"
  }
}

# curl -XGET 'http://localhost:9200/website/news1/AVY0Q4SqdtH0Up0t-WB2?_source=title,text&pretty'
{
  "_index" : "website",
  "_type" : "news1",
  "_id" : "AVY0Q4SqdtH0Up0t-WB2",
  "_version" : 1,
  "found" : true,
  "_source" : {
    "text" : "Just trying this out...",
    "title" : "My first news entry"
  }
}

60.2.4. 检查记录是否存在

代码语言：javascript复制

[root@localhost elasticsearch]# curl -i -XHEAD http://localhost:9200/website/blog/1
HTTP/1.1 200 OK
Content-Type: text/plain; charset=UTF-8
Content-Length: 0

[root@localhost elasticsearch]# curl -i -XHEAD http://localhost:9200/website/blog/100
HTTP/1.1 404 Not Found
Content-Type: text/plain; charset=UTF-8
Content-Length: 0

HTTP/1.1 200 OK 表示已经找到你要的数据

HTTP/1.1 404 Not Found 表示数据不存在

60.2.5. 参数

60.2.5.1. pretty 格式化 json

代码语言：javascript复制

# curl -XGET 'http://localhost:9200/twitter/tweet/1?pretty'
{
  "_index" : "twitter",
  "_type" : "tweet",
  "_id" : "1",
  "_version" : 1,
  "found" : true,
  "_source" : {
    "user" : "kimchy",
    "post_date" : "2009-11-15T14:12:12",
    "message" : "trying out Elasticsearch"
  }
}

es2

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