如何设置过滤器在聚合值达到某个阈值时返回?

时间:2016-09-24 21:53:02

标签: elasticsearch elasticsearch-percolate

以下面的聚合查询为例:

{
  "query": {
    "match_all": {}
  },
  "aggs": {
    "groupBy": {
      "terms": {
        "field": "CustomerName"
      },
      "aggs": {
        "points_sum": {
          "stats": {
            "field": "TransactionAmount"
          }
        }
      }
    }
  },
  "size": 0
}

我有兴趣知道任何CustomerName的平均TransactionAmount(stats.avg)超过某个阈值的所有该客户的购买,只要我将我的平均值高于该阈值的文档编制索引。似乎过滤器设计用于将文档与规则匹配,或多或少,但我找不到使用过滤器匹配基于聚合结果的规则的任何好例子。

这可能吗?过滤器是最好的解决方案吗?还有其他/更好的解决方案吗?提前致谢

1 个答案:

答案 0 :(得分:1)

您可以使用Watcher商业产品并定义以下手表:

PUT _watcher/watch/transaction_alert
{
  "trigger": {
    "schedule": {
      "interval": "1m"
    }
  },
  "input": {
    "search": {
      "request": {
        "indices": "transactions",
        "types": "transaction",
        "body": {
          "query": {
            "match_all": {}
          },
          "size": 0,
          "aggs": {
            "groupBy": {
              "terms": {
                "field": "CustomerName"
              },
              "aggs": {
                "points_sum": {
                  "stats": {
                    "field": "TransactionAmount"
                  }
                }
              }
            }
          }
        }
      }
    }
  },
  "condition": {
    "script": {
      "inline": "return ctx.payload.aggregations.groupBy.buckets.findAll{ cust -> cust.points_sum.avg >= 200}"
    }
  },
  "actions": {
    "send_email": { 
      "email": {
        "to": "<username>@<domainname>", 
        "subject": "Customer Notification - Transaction > 200",
        "body": "The attached customers have a transaction average above $200"
        "attachments" : {
           "data.yml" : {
              "data" : {
                 "format" : "yaml" 
              }
           }
        }
      }
    }
  }
}

<强>更新

总结一下:

使用Logstash实现这一目标的另一种更简单,更便宜的方法。即使elasticsearch输入插件不支持聚合,也可以使用http_poller输入插件,以便定期向Elasticsearch发送聚合查询。然后使用过滤器,您可以检查是否达到了所需的阈值,最后,如果使用email输出插件,则通过电子邮件提醒某人。

配置基本上是这样的(请注意,您的上述聚合查询需要进行URL编码并使用source=... parameter发送到ES)。另请注意,我已根据points_sum.avg(desc)

修改了您的查询以对存储桶进行排序
input {
  http_poller {
    urls => {
      test1 => 'http://localhost:9200/your-index/_search?source=%7B%22query%22%3A%7B%22match_all%22%3A%7B%7D%7D%2C%22aggs%22%3A%7B%22groupBy%22%3A%7B%22terms%22%3A%7B%22field%22%3A%22CustomerName%22%2C%22order%22%3A%7B%22points_sum.avg%22%3A%22desc%22%7D%7D%2C%22aggs%22%3A%7B%22points_sum%22%3A%7B%22stats%22%3A%7B%22field%22%3A%22TransactionAmount%22%7D%7D%7D%7D%7D%2C%22size%22%3A0%7D'
   }
   # checking every 10 seconds
   interval => 10
   codec => "json"
  }
}
filter {
  split {
    field => "[aggregations][groupBy][buckets]" 
  }
}
output {
  if [aggregations][groupBy][buckets][points_sum][avg] > 200 {
    email {
      to => "<username>@<domainname>"
      subject => "Customer Notification - Transaction > 200",
      body => "The customer %{[aggregations][groupBy][buckets][key]} has a transaction average above $200"
    }
  }
}

同意,这是一个非常简单的实现,但它应该工作,你可以在它上面使它变得更聪明,使用Logstash和你的想象力限制是天空; - )

更新2

还可以利用另一个node.js工具调用elasticwatch来执行此操作。