使用ES对中文文章进行分词，并进行词频统计排序

前言：首先有这样一个需求，需要统计一篇10000字的文章，需要统计里面哪些词出现的频率比较高，这里面比较重要的是如何对文章中的一段话进行分词，例如“北京是×××的首都”，“北京”，“×××”，“中华”，“华人”，“人民”，“共和国”，“首都”这些是一个词，需要切分出来，而“京是”“民共”这些就不是有意义的词，所以不能分出来。这些分词的规则如果自己去写，是一件很麻烦的事，利用开源的IK分词，就可以很容易的做到。并且可以根据分词的模式来决定分词的颗粒度。

ik_max_word: 会将文本做最细粒度的拆分，比如会将“×××国歌”拆分为“×××,中华人民,中华,华人,人民共和国,人民,人,民,共和国,共和,和,国国,国歌”，会穷尽各种可能的组合；

ik_smart: 会做最粗粒度的拆分，比如会将“×××国歌”拆分为“×××,国歌”。

一：首先要准备环境

如果有ES环境可以跳过前两步，这里我假设你只有一台刚装好的CentOS6.X系统，方便你跑通这个流程。

（1）安装jdk。

$ wget http://download.oracle.com/otn-pub/java/jdk/8u111-b14/jdk-8u111-linux-x64.rpm
$ rpm -ivh jdk-8u111-linux-x64.rpm

（2）安装ES

$ wget  https://download.elastic.co/elasticsearch/release/org/elasticsearch/distribution/rpm/elasticsearch/2.4.2/elasticsearch-2.4.2.rpm
$ rpm -iv elasticsearch-2.4.2.rpm

（3）安装IK分词器

在github上面下载1.10.2版本的ik分词，注意：es版本为2.4.2，兼容的版本为1.10.2。

$ mkdir /usr/share/elasticsearch/plugins/ik
$ wget https://github.com/medcl/elasticsearch-analysis-ik/releases/download/v1.10.2/elasticsearch-analysis-ik-1.10.2.zip
$ unzip elasticsearch-analysis-ik-1.10.2.zip -d /usr/share/elasticsearch/plugins/ik

（4）配置ES

$ vim /etc/elasticsearch/elasticsearch.yml
###### Cluster ######
cluster.name: test
###### Node ######
node.name: test-10.10.10.10
node.master: true
node.data: true
###### Index ######
index.number_of_shards: 5
index.number_of_replicas: 0
###### Path ######
path.data: /data/elk/es
path.logs: /var/log/elasticsearch
path.plugins: /usr/share/elasticsearch/plugins
###### Refresh ######
refresh_interval: 5s
###### Memory ######
bootstrap.mlockall: true
###### Network ######
network.publish_host: 10.10.10.10
network.bind_host: 0.0.0.0
transport.tcp.port: 9300
###### Http ######
http.enabled: true
http.port : 9200
###### IK ########
index.analysis.analyzer.ik.alias: [ik_analyzer]
index.analysis.analyzer.ik.type: ik
index.analysis.analyzer.ik_max_word.type: ik
index.analysis.analyzer.ik_max_word.use_smart: false
index.analysis.analyzer.ik_smart.type: ik
index.analysis.analyzer.ik_smart.use_smart: true
index.analysis.analyzer.default.type: ik

（5）启动ES

$ /etc/init.d/elasticsearch start

（6）检查es节点状态

$ curl localhost:9200/_cat/nodes?v    #看到一个节点正常
host         ip           heap.percent ram.percent load node.role master name
10.10.10.10 10.10.10.10           16          52 0.00 d         *      test-10.10.10.10

$ curl localhost:9200/_cat/health?v   #集群状态为green
epoch      timestamp cluster            status node.total node.data shards pri relo init
1483672233 11:10:33  test               green           1         1     0   0    0    0

二：检测分词功能

（1）创建测试索引

$ curl -XPUT http://localhost:9200/test

（2）创建mapping

$ curl -XPOST http://localhost:9200/test/fulltext/_mapping -d'
  {
      "fulltext": {
               "_all": {
              "analyzer": "ik"
          },
          "properties": {
              "content": {
                  "type" : "string",
                  "boost" : 8.0,
                  "term_vector" : "with_positions_offsets",
                  "analyzer" : "ik",
                  "include_in_all" : true
              }
          }
      }
  }'

（3）测试数据

$ curl 'http://localhost:9200/index/_analyze?analyzer=ik&pretty=true' -d '{ "text":"美国留给伊拉克的是个烂摊子吗" }'

返回内容：

{
  "tokens" : [ {
    "token" : "美国",
    "start_offset" : 0,
    "end_offset" : 2,
    "type" : "CN_WORD",
    "position" : 0
  }, {
    "token" : "留给",
    "start_offset" : 2,
    "end_offset" : 4,
    "type" : "CN_WORD",
    "position" : 1
  }, {
    "token" : "伊拉克",
    "start_offset" : 4,
    "end_offset" : 7,
    "type" : "CN_WORD",
    "position" : 2
  }, {
    "token" : "伊",
    "start_offset" : 4,
    "end_offset" : 5,
    "type" : "CN_WORD",
    "position" : 3
  }, {
    "token" : "拉",
    "start_offset" : 5,
    "end_offset" : 6,
    "type" : "CN_CHAR",
    "position" : 4
  }, {
    "token" : "克",
    "start_offset" : 6,
    "end_offset" : 7,
    "type" : "CN_WORD",
    "position" : 5
  }, {
    "token" : "个",
    "start_offset" : 9,
    "end_offset" : 10,
    "type" : "CN_CHAR",
    "position" : 6
  }, {
    "token" : "烂摊子",
    "start_offset" : 10,
    "end_offset" : 13,
    "type" : "CN_WORD",
    "position" : 7
  }, {
    "token" : "摊子",
    "start_offset" : 11,
    "end_offset" : 13,
    "type" : "CN_WORD",
    "position" : 8
  }, {
    "token" : "摊",
    "start_offset" : 11,
    "end_offset" : 12,
    "type" : "CN_WORD",
    "position" : 9
  }, {
    "token" : "子",
    "start_offset" : 12,
    "end_offset" : 13,
    "type" : "CN_CHAR",
    "position" : 10
  }, {
    "token" : "吗",
    "start_offset" : 13,
    "end_offset" : 14,
    "type" : "CN_CHAR",
    "position" : 11
  } ]
}

三：开始导入真正的数据

（1）将中文的文本文件上传到linux上面。

$ cat /tmp/zhongwen.txt
京津冀重污染天气持续 督查发现有企业恶意生产
《孤芳不自赏》被指“抠像演戏” 制片人：特效不到位
奥巴马不顾特朗普反对坚持外迁关塔那摩监狱囚犯
.
.
.
.
韩媒：日本叫停韩日货币互换磋商 韩财政部表遗憾
中国百万年薪须交40多万个税 精英无奈出国发展

注意：确保文本文件编码为utf-8，否则后面传到es会乱码。

$ vim /tmp/zhongwen.txt

命令模式下输入：set fineencoding,即可看到fileencoding=utf-8。

如果是 fileencoding=utf-16le，则输入：set fineencoding=utf-8

（2）创建索引和mapping

创建索引

$ curl -XPUT http://localhost:9200/index

创建mapping  #对要分词的字段message进行分词器设置和fielddata设置。

$ curl -XPOST http://localhost:9200/index/logs/_mapping -d '
{
  "logs": {
    "_all": {
      "analyzer": "ik"
    },
    "properties": {
      "path": {
        "type": "string"
      },
      "@timestamp": {
        "format": "strict_date_optional_time||epoch_millis",
        "type": "date"
      },
      "@version": {
        "type": "string"
      },
      "host": {
        "type": "string"
      },
      "message": {
        "include_in_all": true,
        "analyzer": "ik",
        "term_vector": "with_positions_offsets",
        "boost": 8,
        "type": "string",
        "fielddata" : { "format" : "true" }
      },
      "tags": {
        "type": "string"
      }
    }
  }
}'

（3）使用logstash 将文本文件写入到es中

安装logstash

$ wget https://download.elasticsearch.org/elasticsearch/release/org/elasticsearch/distribution/rpm/elasticsearch/2.1.1/elasticsearch-2.1.1.rpm
$ rpm -ivh  logstash-2.1.1.rpm

配置logstash

$ vim /etc/logstash/conf.d/logstash.conf
input {
  file {
      codec => 'json'
      path => "/tmp/zhongwen.txt"
      start_position => "beginning"
  }
}
output {
    elasticsearch {
      hosts => "10.10.10.10:9200"
      index => "index"
      flush_size => 3000
      idle_flush_time => 2
      workers => 4
     }
  stdout { codec => rubydebug }
}

启动

$ /etc/init.d/logstash start

查看stdout输出，就能判断是否写入es中。

$ tail -f /var/log/logstash.stdout

（4）检查索引中是否有数据

$ curl 'localhost:9200/_cat/indices/index?v'  #可以看到有6007条数据。
health status index pri rep docs.count docs.deleted store.size pri.store.size
green  open   index   5   0       6007            0      2.5mb          2.5mb

$ curl -XPOST  "http://localhost:9200/index/_search?pretty"
{
  "took" : 1,
  "timed_out" : false,
  "_shards" : {
    "total" : 5,
    "successful" : 5,
    "failed" : 0
  },
  "hits" : {
    "total" : 5227,
    "max_score" : 1.0,
    "hits" : [ {
      "_index" : "index",
      "_type" : "logs",
      "_id" : "AVluC7Dpbw7ZlXPmUTSG",
      "_score" : 1.0,
      "_source" : {
        "message" : "中国百万年薪须交40多万个税 精英无奈出国发展",
        "tags" : [ "_jsonparsefailure" ],
        "@version" : "1",
        "@timestamp" : "2017-01-05T09:52:56.150Z",
        "host" : "0.0.0.0",
        "path" : "/tmp/333.log"
      }
    }, {
      "_index" : "index",
      "_type" : "logs",
      "_id" : "AVluC7Dpbw7ZlXPmUTSN",
      "_score" : 1.0,
      "_source" : {
        "message" : "奥巴马不顾特朗普反对坚持外迁关塔那摩监狱囚犯",
        "tags" : [ "_jsonparsefailure" ],
        "@version" : "1",
        "@timestamp" : "2017-01-05T09:52:56.222Z",
        "host" : "0.0.0.0",
        "path" : "/tmp/333.log"
      }
}

四：开始计算分词的词频，排序

（1）查询所有词出现频率最高的top10

$ curl -XGET "http://localhost:9200/index/_search?pretty" -d'
{
    "size" : 0,
    "aggs" : {
        "messages" : {
            "terms" : {
               "size" : 10,
              "field" : "message"
            }
        }
    }
}'

返回结果

{
  "took" : 3,
  "timed_out" : false,
  "_shards" : {
    "total" : 5,
    "successful" : 5,
    "failed" : 0
  },
  "hits" : {
    "total" : 6007,
    "max_score" : 0.0,
    "hits" : [ ]
  },
  "aggregations" : {
    "messages" : {
      "doc_count_error_upper_bound" : 154,
      "sum_other_doc_count" : 94992,
      "buckets" : [ {
        "key" : "一",
        "doc_count" : 1582
      }, {
        "key" : "后",
        "doc_count" : 560
      }, {
        "key" : "人",
        "doc_count" : 541
      }, {
        "key" : "家",
        "doc_count" : 538
      }, {
        "key" : "出",
        "doc_count" : 489
      }, {
        "key" : "发",
        "doc_count" : 451
      }, {
        "key" : "个",
        "doc_count" : 440
      }, {
        "key" : "州",
        "doc_count" : 421
      }, {
        "key" : "岁",
        "doc_count" : 405
      }, {
        "key" : "子",
        "doc_count" : 402
      } ]
    }
  }
}

（2）查询所有两字词出现频率最高的top10

$ curl -XGET "http://localhost:9200/index/_search?pretty" -d'
{
    "size" : 0,
    "aggs" : {
        "messages" : {
            "terms" : {
                 "size" : 10,
              "field" : "message",
                "include" : "[\u4E00-\u9FA5][\u4E00-\u9FA5]"
            }
        }
    },
   "highlight": {
     "fields": {
      "message": {}
    }
  }
}'

返回

{
  "took" : 22,
  "timed_out" : false,
  "_shards" : {
    "total" : 5,
    "successful" : 5,
    "failed" : 0
  },
  "hits" : {
    "total" : 6007,
    "max_score" : 0.0,
    "hits" : [ ]
  },
  "aggregations" : {
    "messages" : {
      "doc_count_error_upper_bound" : 73,
      "sum_other_doc_count" : 42415,
      "buckets" : [ {
        "key" : "女子",
        "doc_count" : 291
      }, {
        "key" : "男子",
        "doc_count" : 264
      }, {
        "key" : "竟然",
        "doc_count" : 257
      }, {
        "key" : "上海",
        "doc_count" : 255
      }, {
        "key" : "这个",
        "doc_count" : 238
      }, {
        "key" : "女孩",
        "doc_count" : 174
      }, {
        "key" : "这些",
        "doc_count" : 167
      }, {
        "key" : "一个",
        "doc_count" : 159
      }, {
        "key" : "注意",
        "doc_count" : 143
      }, {
        "key" : "这样",
        "doc_count" : 142
      } ]
    }
  }
}

（3）查询所有两字词且不包含“女”字，出现频率最高的top10

curl -XGET "http://localhost:9200/index/_search?pretty" -d'
{
    "size" : 0,
    "aggs" : {
        "messages" : {
            "terms" : {
              "size" : 10,
              "field" : "message",
              "include" : "[\u4E00-\u9FA5][\u4E00-\u9FA5]",
              "exclude" : "女.*"
            }
        }
    },
   "highlight": {
     "fields": {
      "message": {}
    }
  }
}'

返回

{
  "took" : 19,
  "timed_out" : false,
  "_shards" : {
    "total" : 5,
    "successful" : 5,
    "failed" : 0
  },
  "hits" : {
    "total" : 5227,
    "max_score" : 0.0,
    "hits" : [ ]
  },
  "aggregations" : {
    "messages" : {
      "doc_count_error_upper_bound" : 71,
      "sum_other_doc_count" : 41773,
      "buckets" : [ {
        "key" : "男子",
        "doc_count" : 264
      }, {
        "key" : "竟然",
        "doc_count" : 257
      }, {
        "key" : "上海",
        "doc_count" : 255
      }, {
        "key" : "这个",
        "doc_count" : 238
      }, {
        "key" : "这些",
        "doc_count" : 167
      }, {
        "key" : "一个",
        "doc_count" : 159
      }, {
        "key" : "注意",
        "doc_count" : 143
      }, {
        "key" : "这样",
        "doc_count" : 142
      }, {
        "key" : "重庆",
        "doc_count" : 142
      }, {
        "key" : "结果",
        "doc_count" : 137
      } ]
    }
  }
}

还有更多的分词策略，例如设置近义词（设置“番茄”和“西红柿”为同义词，搜索“番茄”，“西红柿”也会出来），设置拼音分词（搜索“zhonghua”，“中华”也可以搜索出来）等等。