开篇
分而治之是大数据计算的基本思路，特分享一款天然的分布式全文搜索引擎-Elastic Search，而如何归并，是分而治之的重点难题。在HA集群节点架构中，各个节点主备分片如何分配，各分片搜索结果如何得出最终结果…
引入 | 记一次kibana执行dsl脚本实战的思考过程
适合场景
当千万乃至更大数据量，需要像传统DBMS关系型数据库一样，实现在海量数据中作模糊搜索，全文搜索，又需要有一定程度的检索效率，突破传统DBMS性能瓶颈，那么ES很适合与关系型数据库形成互补，ES在搜索领域拥有强悍的性能，而传统DBMS关系型数据库分库分表组合查询相当麻烦，而ES组合灵活-自动路由（开发者无需在业务层作过多干涉），当然，在大数据量复杂查询的话，深度分页需要优化下，简单的查询几十亿问题不大，若超大则可上集群，再可上ES-ClickHouse.
重要考虑
虽然传统DBMS关系型数据库表中数据，可通过一系列方案-结合实际业务作数据同步至ES（数据建模），但当大批量数据同步到ES单节点，或从节点往集群迁移copy数据，基于logstash亦或是基于ES-Transport批量提交数据，数据需要实时更新亦或离线初始化，还有就是聚合的性能以及一些高级属性，比如copy to，script脚步引擎应用，mapping设计之动态模版映射动态索引或为指定索引匹配预制动态模版等等…
脚本引擎历史
一、Elasticsearch Script History-分布式全文搜索-脚本引擎历史
在ES早期的版本中，使用MVEL脚本，但为解决安全隐患问题，于是Groovy脚本诞生。
随之出现的安全漏洞跟内存泄露问题，于是在ES5.0版本之际，painless脚本官宣，距今也有数年之久，painless脚本浮现在开发者眼前。
脚本引擎应用
二、Elasticsearch Script ApplyCenarios-分布式全文搜索-脚本引擎应用场景
我们都很熟悉的认知到Elasticsearch全文搜索引擎，在其各版本系列中提供了丰富的dsl语法-增删改查-这里以6.x版本系列-6.8.6为例。
在80%以上的业务场景中作增删改查游刃有余，但应用于相对复杂的业务场景：
多字段自定义更新、自定义reindex、自定义数组字段动态添加...
https://www.elastic.co/guide/en/elasticsearch/painless/6.8/painless-regexes.html
当然基于脚本引擎手动开发插件也是可以实现的。
https://www.elastic.co/guide/en/elasticsearch/reference/current/modules-scripting-engine.html
从painless脚本的衍生意义理解是"无痛"无漏洞的，但尤其需要注意的地方-不能以root账户启动es，不要公开es路径至其他用户。
从官方Script使用的介绍来看，首要就是性能问题，其次就是使用业务场景，ebay在性能优化实践英文版中也有体现，
https://www.ebayinc.com/stories/blogs/tech/elasticsearch-performance-tuning-practice-at-ebay/
这里也mark下中文版。
https://www.infoq.cn/article/elasticsearch-performance-tuning-practice-at-ebay
其中，80%以上的业务场景：参考小编汇总Elasticsearch+Kibana+Dsl-Crud大全
DSL语法大全
GET _search
{
"query": {
"match_all": {}
}
}
#节点信息
GET _cat/nodes?v
GET _cat/master
#各节点机器存储信息
GET _cat/allocation?v
#索引信息
GET _cat/indices?v
GET /_cat/count
GET /_cat/count/yd-2021
GET _cat/indices/yd-hlht-test-2022
#分片信息
GET _cat/shards?v
GET _cat/shards/yd-hlht-test-2022
#查看所有分片的恢复状况-该命令查看initializing分片的恢复进度
GET _cat/recovery/
GET _cat/recovery/yd-hlht-test-2022
GET _cluster/health
GET _cluster/nodes/hot_threads
#查看分片未分配原因
GET /_cat/shards?h=index,shard,prirep,state,unassigned.*,unassigned.reason | grep UNASSIGNED
#查看具体分片未分配原因
GET _cluster/allocation/explain
{
"index":"yd-hlht-test-2022",
"shard":0,
"primary":false
}
#注册快照存储库-仓库共享
PUT _snapshot/my_backup
{
"type": "fs",
"settings": {
"location": "/home/user/yxd179/es/backup"
}
}
#查看仓库信息
GET /_snapshot/my_backup?pretty
#查看快照存储库保存结果
GET _snapshot
#创建快照，这个会备份所有打开的索引到my_backup仓库下并命名为snapshot_yd的快照里。这个调用会立刻返回，然后快照会在后台运行。若是希望在脚本中一直等待到完成，可通过添加 wait_for_completion 标记实现，这个会阻塞调用直到快照完成（如果是大型快照，会花很长时间才返回），其中只会备份索引809iJpOmSI2ZmJrUqKRR0Q信息
PUT /_snapshot/my_backup/snapshot_yd?wait_for_completion=true
{
"indices": "809iJpOmSI2ZmJrUqKRR0Q",
"ignore_unavailable": true,
"include_global_state": false,
"metadata": {
"taken_by": "phr",
"taken_because": "backup before upgrading"
}
}
#查看快照
GET /_snapshot/my_backup/snapshot_yd
#查看所有快照
GET /_snapshot/my_backup/_all
#删除快照
DELETE /_snapshot/my_backup/snapshot_yd
#监控快照创建或恢复过程
GET /_snapshot/my_backup/snapshot_yd/_status
#恢复快照
POST /_snapshot/my_backup/snapshot_yd/_restore
#动态模板
PUT /_template/yxd179_tpl
{
"index_patterns": [
"yxd179-2021*"
],
"settings": {
"number_of_shards": 1,
"number_of_replicas": 1
},
"mappings": {
"yd": {
"dynamic_templates": [
{
"strings": {
"match_mapping_type": "string",
"mapping": {
"type": "text",
"index": true,
"copy_to": "full_context",
"analyzer": "ik_max_word",
"fields": {
"keyword": {
"type": "keyword",
"ignore_above": 256
}
}
}
}
}
],
"properties": {
"full_context": {
"type": "text",
"analyzer": "ik_max_word",
"fielddata": true,
"store": true
}
}
}
}
}
#副本分片分配设置
PUT /yxd179-2021/_settings
{
"number_of_replicas": "1"
}
#分页查询
GET /yxd179-2021/yd/_search
{
"from": 0,
"size": 30
}
#根据ID查询
GET /yxd179-2021/yd/647461503271768064
#bool query dsl查询
GET /yxd179-2021/yd/_search
{
"query": {
"bool": {
"must": [
{
"bool": {
"should": [
{
"match": {
"regNumber": "20203030651"
}
}
]
}
},
{
"term": {
"status": "1"
}
}
]
}
},
"sort": [
{
"createTime": {
"order": "desc"
}
}
],
"from": 0,
"size": 10
}
#允许ES最大滚动数目分配设置
PUT /yxd179-2021/_settings
{
"index": {
"max_result_window": 13000000
}
}
#查看字段分词分析过程
POST /yxd179-2021/_analyze
{
"field": "regNumber",
"text": "国械标准20203030651号"
}
#模糊查询匹配
GET /yxd179-2021/yd/_search
{
"query": {
"bool": {
"must": [
{
"bool": {
"should": [
{
"wildcard": {
"regNumber.keyword": "*20203030651*"
}
}
]
}
},
{
"term": {
"status": "1"
}
}
]
}
},
"sort": [
{
"createTime": {
"order": "desc"
}
}
],
"from": 0,
"size": 10
}
#对指定字段设置分词器查询
GET /yxd179-2021/yd/_search
{
"query": {
"bool": {
"must": [
{
"match": {
"hdsd0001004": {
"query": "1828551417",
"analyzer": "char_analyzer"
}
}
}
]
}
},
"from": 0,
"size": 30
}
#模糊查询匹配
GET /yxd179-2021/yd/_search
{
"query": {
"bool": {
"must": [
{
"wildcard": {
"hdsd0001002.keyword": "*yxd179*"
}
}
]
}
},
"from": 0,
"size": 30
}
#关闭索引:
POST yxd179-2021/_close
#打开索引:
POST yxd179-2021/_open
#对指定字段设置分词器
PUT /yxd179-2021/_mapping/yd
{
"properties": {
"hdsd0001004": {
"type": "text",
"analyzer": "char_analyzer"
}
}
}
#查看mapping结构体信息
GET yxd179-2021/_mapping
#设置分词分析器
PUT yxd179-2021/_settings
{
"analysis": {
"analyzer": {
"char_analyzer": {
"tokenizer": "char_tokenizer",
"filter": "lowercase"
}
},
"tokenizer": {
"char_tokenizer": {
"type": "pattern",
"pattern": "|"
}
}
}
}
#minimum_should_match
GET /yxd179-2021/yd/_search
{
"query": {
"query_string": {
"query": "182855141y7",
"type": "phrase",
"operator": "AND",
"minimum_should_match": "100%",
"fields": [
"hdsd0001004"
]
}
}
}
#显示字段
GET /yxd179-2021/yd/_search
{
"_source": {
"include": [
"id",
"productId"
]
},
"query": {
"bool": {
"must": [
{
"terms": {
"productId": [
636654265306419462
]
}
}
]
}
},
"from": 0,
"size": 30
}
#高亮查询
GET /yxd179-2021/yd/_search
{
"query": {
"bool": {
"must": [
{
"bool": {
"should": []
}
},
{
"term": {
"status": "1"
}
},
{
"term":{
"id":636662671736099971
}
}
]
}
},
"sort": [
{
"id": {
"order": "asc"
}
}
],
"highlight": {
"pre_tags": [
"<span class='title-key'>"
],
"post_tags": [
"</span>"
],
"fields": {
"commonName": {
"type": "plain"
}
}
},
"from": 0,
"size": 10
}
#read_only_allow_delete
PUT /yxd179-2021/_settings
{
"index":{
"blocks":{
"read_only_allow_delete":"false"
}
}
}
#查询模板
GET /_template
GET /yxd179-2021*/yd/_search
{
"from": 0,
"size": 30
}
#单个字段bool查询
GET /yxd179-2021/yd/_search
{
"query": {
"bool": {
"must": [
{
"term": {
"id": "636651493706133509"
}
}
]
}
},
"from": 0,
"size": 30
}
#批量
POST /_bulk
{"index":{"_index":"yxd179-2021","_type":"yd","_id":"65965969996688"}}
{"id":"65965969996688","HDSD0001002":"sdff","HDSD0001008":"fsdf","HDSD0001006":"000000000000000000","create_time":"2021-07-29","cancel_flag":0}
{"index":{"_index":"yxd179-2021","_type":"yd","_id":"66049829996688"}}
{"id":"66049829996688","HDSD0001002":"sdgsdg","HDSD0001008":"fsdfsdf","HDSD0001006":"000000000000000000","create_time":"2021-07-29","cancel_flag":1}
#外层交集查询
GET /yxd179-2021/yd/_search
{
"query": {
"bool": {
"must": [
{
"bool": {
"should": [
{
"match": {
"regNumber": "国sd20182642128"
}
}
]
}
},
{
"term": {
"status": "1"
}
}
]
}
},
"sort": [
{
"createTime": {
"order": "desc"
}
}
],
"from": 0,
"size": 10
}
#复杂bool带权重查询-得分排序
GET /yxd179-2021/yd/_search
{
"from": 0,
"size": 10,
"query": {
"bool": {
"must": [
{
"bool": {
"must": [
{
"term": {
"cancelFlag": {
"value": "0",
"boost": 1
}
}
}
],
"adjust_pure_negative": true,
"boost": 1
}
},
{
"bool": {
"should": [
{
"match": {
"yhe": {
"query": "张",
"operator": "OR",
"prefix_length": 0,
"max_expansions": 50,
"fuzzy_transpositions": true,
"lenient": false,
"zero_terms_query": "NONE",
"auto_generate_synonyms_phrase_query": true,
"boost": 1
}
}
},
{
"match": {
"yhr": {
"query": "张",
"operator": "OR",
"prefix_length": 0,
"max_expansions": 50,
"fuzzy_transpositions": true,
"lenient": false,
"zero_terms_query": "NONE",
"auto_generate_synonyms_phrase_query": true,
"boost": 1
}
}
},
{
"match": {
"yht": {
"query": "张",
"operator": "OR",
"prefix_length": 0,
"max_expansions": 50,
"fuzzy_transpositions": true,
"lenient": false,
"zero_terms_query": "NONE",
"auto_generate_synonyms_phrase_query": true,
"boost": 1
}
}
},
{
"match": {
"yhg": {
"query": "张",
"operator": "OR",
"prefix_length": 0,
"max_expansions": 50,
"fuzzy_transpositions": true,
"lenient": false,
"zero_terms_query": "NONE",
"auto_generate_synonyms_phrase_query": true,
"boost": 1
}
}
}
],
"adjust_pure_negative": true,
"boost": 1
}
}
],
"adjust_pure_negative": true,
"boost": 1
}
},
"explain": true,
"sort": [
{
"id": {
"order": "desc"
}
}
]
}
#查询耗时统计分析profile
GET /yxd179-2021/yd/_search
{
"profile": true,
"query":{
"term":{
"tu":6583120
}
}
}
#根据ID修改
POST /yxd179-2021/yd/b00e89b652484b0b8da16e090302e012/_update
{
"doc":{
"fd":"1"
}
}
#修改_update_by_query脚本引擎painless
POST /yxd179-2021/_update_by_query
{
"query":{
"term":{
"fdh":6583120
}
},
"script":{
"lang":"painless",
"source": "ctx._source.cancelFlag=params.cancelFlag;ctx._source.updateTime=params.updateTime",
"params": {
"cancelFlag":"0",
"updateTime":"2021-07-28T01:17:36.000Z"
}
}
}
#交集查询-且保留-全
GET /yxd179-2021/yd/_search
{
"query": {
"bool": {
"must": [
{
"term": {
"cancelFlag": "0"
}
},
{
"bool": {
"must": [
{
"wildcard": {
"hdsd0001002.keyword": "*yxd179*"
}
},
{
"match": {
"hdsd0001003": "2"
}
}
]
}
}
]
}
},
"sort": [
{
"id": {
"order": "desc"
}
}
],
"highlight": {
"pre_tags": [
"<span class='title-key'>"
],
"post_tags": [
"</span>"
],
"fields": {
"hdsd0001002": {
"type": "plain"
}
}
},
"from": 0,
"size": 30
}
#外层交集查询-里层交集查询
GET /yxd179-2021/yd/_search
{
"from": 0,
"size": 10,
"query": {
"bool": {
"must": [
{
"bool": {
"must": [
{
"term": {
"cancelFlag": {
"value": "0",
"boost": 1
}
}
}
],
"adjust_pure_negative": true,
"boost": 1
}
},
{
"bool": {
"must": [
{
"match": {
"hdsd0001002": {
"query": "张",
"operator": "OR",
"prefix_length": 0,
"max_expansions": 50,
"fuzzy_transpositions": true,
"lenient": false,
"zero_terms_query": "NONE",
"auto_generate_synonyms_phrase_query": true,
"boost": 1
}
}
},
{
"match": {
"hdsd0001003": {
"query": "2",
"operator": "OR",
"prefix_length": 0,
"max_expansions": 50,
"fuzzy_transpositions": true,
"lenient": false,
"zero_terms_query": "NONE",
"auto_generate_synonyms_phrase_query": true,
"boost": 1
}
}
}
],
"adjust_pure_negative": true,
"boost": 1
}
}
],
"adjust_pure_negative": true,
"boost": 1
}
},
"explain": true
}
#并集查询
GET /yxd179-2021/yd/_search
{
"from": 0,
"size": 10,
"query": {
"bool": {
"must": [
{
"term": {
"cancelFlag": {
"value": "0",
"boost": 1
}
}
}
],
"should": [
{
"match": {
"hdsd0001002": {
"query": "张",
"operator": "OR",
"prefix_length": 0,
"max_expansions": 50,
"fuzzy_transpositions": true,
"lenient": false,
"zero_terms_query": "NONE",
"auto_generate_synonyms_phrase_query": true,
"boost": 1
}
}
}
],
"adjust_pure_negative": true,
"boost": 1
}
},
"explain": true
}
#并集查询-字段显示
GET /yxd179-2021/yd/_search
{
"from": 0,
"size": 10,
"query": {
"bool": {
"must": [
{
"match": {
"cancelFlag": {
"query": "0",
"operator": "AND",
"prefix_length": 0,
"max_expansions": 50,
"fuzzy_transpositions": true,
"lenient": false,
"zero_terms_query": "NONE",
"auto_generate_synonyms_phrase_query": true,
"boost": 1
}
}
}
],
"should": [
{
"match": {
"hdsd0001002": {
"query": "张",
"operator": "OR",
"prefix_length": 0,
"max_expansions": 50,
"fuzzy_transpositions": true,
"lenient": false,
"zero_terms_query": "NONE",
"auto_generate_synonyms_phrase_query": true,
"boost": 1
}
}
},
{
"match": {
"hdsd0001002.pinyin": {
"query": "zhang",
"operator": "OR",
"prefix_length": 0,
"max_expansions": 50,
"fuzzy_transpositions": true,
"lenient": false,
"zero_terms_query": "NONE",
"auto_generate_synonyms_phrase_query": true,
"boost": 1
}
}
}
],
"adjust_pure_negative": true,
"boost": 1
}
},
"explain": true,
"_source": {
"includes": [
"id",
"th001Id",
"createTime",
"updateTime",
"hdsd0001001",
"hdsd0001002",
"cancelFlag"
],
"excludes": []
}
}
#若需要更频繁的更新，可以使用es api强制更新
GET /yxd179-2021/_refresh
#根据ID删除
DELETE /yxd179-2021/yd/ud6-5XkBwVbB7HKjg5k0
#删除索引
DELETE /yxd179-2021
#删除模板-动态mapping
DELETE /_template/yxd179_tpl
#排序
GET /yxd179-2021/yd/_search
{
"sort": [
{
"createTime": {
"order": "desc"
}
}
],
"from": 0,
"size": 30
}
脚本引擎案例
三、Elasticsearch Script ActualCombat-分布式全文搜索-脚本引擎实战
这里仅以Update-By-Query为例：
其中，lang指定脚本引擎：painless，source中为script脚本片段，params为脚本参数值。
之所以通过params传递，可突破ES对脚本编译限制，虽然也可以通过下面操作来修改该解析上限的配置：
PUT /_cluster/settings
{
"transient": {
"script.max_compilations_per_minute": 40
}
}
重要：对于大批量数据，ES都需要单独的编译解析，当进行bulk update时，若是每一个脚本都实时编译的话，可想而知很快就会达到上限。知其然知其所以然，对于ES中都只会在第一次进行解析这个脚本，之后便无需再次解析，当脚本中有常数变量时，ES会实时编译脚本，故结合script中的param功能，设法将脚本中的变量通过param传递进去，从而可以从根本上解决脚本编译解析限制的问题。
接下来，我们看下在Java中怎么样基于6.8.6版本构建tcp client执行painless脚本引擎？
补充：对updateByQuery API的调用从获取索引快照开始，索引使用内部版本控制找到任何文档。
试想当一个文档在快照的时间和索引请求过程之间发生变化时，会发生版本冲突。当版本匹配时，updateByQuery更新文档并增加版本号。上述为了防止版本冲突导致updateByQuery中止，还可以设abortOnVersionConflict(false)，之所以这么做，是有可能它试图获取在线映射更改，而版本冲突意味着在相同时间开始updateByQuery和试图更新文档的冲突文档，该更新将获取在线映射更新，updateByQuery也可以通过指定pipeline来使用ingest节点。其中UpdateByQueryRequestBuilder API可支持过滤更新的文档，限制要更新的文档总数，并使用脚本更新文档，即时刷入磁盘，重试次数等。
Retry： 当客户端A、B几乎同时获取同一个文档, 一并获得_version版本信息, 假设此时_version=1。
接着，客户端A修改文档中的部分内容, 将修改写入索引。而Elasticsearch在写入索引时, 检查客户端A提交的文档的版本信息(这里仍然是1) 和 现存的文档的版本信息(这里也是1), 发现相同后, 执行写入操作, 并修改版本号_version=2。然后客户端B也修改文档中的部分内容, 其操作写回索引的速度稍慢，此时同样执行写入过程，ES发现客户端B提交的文档的版本为1, 而现存文档的版本为2，即发生冲突，此次partial update将失败-重试。
并发控制策略：partial update并发控制策略-乐观锁
结尾
小试牛刀案例：如何通过脚本引擎指定多个字段update？
方式No.1：
ctx._source.putAll(params)
方式No.2：
for (k in params.keySet()){if (!k.equals('ctx')){ctx._source.put(k, params.get(k))
末尾：后续Java框架体系，数据库技术体系，大数据体系进阶案例实战都会同时更新，微信公众号同步，旨在分享的初衷，欢迎提出宝贵建议^_^
