使用jq批量修改es index template的lifecycle配置

aka: use jq tool to modify es index template lifecycle setting in bulk

新版本的es index template不支持通过结合索引匹配+优先级配置的方式来叠加批量修改已存在的索引模版(legacy template 支持)，只支持通过compose实现类似用法，部分场景会带来大量的搬砖成本(例如修改skywalking的索引模板中的生命周期配置或者索引副本数配置)

引入脚本:

#!/bin/bash
#set -exu
set -ue
host="127.0.0.1:9200"
username="elastic"
password="elastic"
ilm_name="sw-default-ilm"

curl_options=(
  "-u" "$username:$password"
  "-s"
)

es_sw_templates=`curl ${curl_options[@]} "$host/_cat/templates/sw*?s=name" | awk '{print $1}'`
# bak
curl ${curl_options[@]} "${host}/_index_template?pretty" > es-${host}-index-templates_`date +%F%T`.bak.json

for template in ${es_sw_templates[@]}
do
  if [[ $template == "sw_segment" ]]
  then
    continue
  fi
  echo PUT /_index_template/${template}
  new_template=""
  new_template=`curl ${curl_options[@]} "${host}/_index_template/${template}" | jq '.index_templates[0].index_template |  .template.settings.index.lifecycle.name |= "'${ilm_name}'"'`
  curl -X PUT -H "Content-Type: application/json" ${curl_options[@]} "${host}/_index_template/${template}" -d "${new_template}"
  echo
done

也可以将修改 lifecycle.name 改为修改 compose 以及修改 refresh_interval

new_template=`curl ${curl_options[@]} "${host}/_index_template/${template}" | jq '.index_templates[0].index_template |  .composed_of = ["sw_default_ilm"] | .template.settings.index.refresh_interval = "180s"'`