Question

我有一个需求，我需要根据TargetHealth状态为AWS目标组中的目标调用某些功能或说命令。我执行以下操作以获取目标组中的目标列表：-

aws elbv2 --region us-east-1 describe-target-health --target-group-arn=******

{
    "TargetHealthDescriptions": [{
            "Target": {
                "Id": "***",
                "Port": 80
            },
            "TargetHealth": {
                "State": "initial",
                "Reason": "Elb.RegistrationInProgress",
                "Description": "Target registration is in progress"
            }
        },
        {
            "Target": {
                "Id": "***",
                "Port": 80
            },
            "TargetHealth": {
                "State": "unhealthy",
                "Reason": "Target.Timeout",
                "Description": "Connection to target timed out"
            }
        },
        {
            "HealthCheckPort": "80",
            "Target": {
                "Id": "***",
                "Port": 80
            },
            "TargetHealth": {
                "State": "healthy"
            }
        },
        {
            "HealthCheckPort": "80",
            "Target": {
                "Id": "***",
                "Port": 80
            },
            "TargetHealth": {
                "State": "healthy"
            }
        },
        {
            "HealthCheckPort": "80",
            "Target": {
                "Id": "***",
                "Port": 80
            },
            "TargetHealth": {
                "State": "healthy"
            }
        },
        {
            "HealthCheckPort": "80",
            "Target": {
                "Id": "***",
                "Port": 80
            },
            "TargetHealth": {
                "State": "healthy"
            }
        },
        {
            "HealthCheckPort": "80",
            "Target": {
                "Id": "***",
                "Port": 80
            },
            "TargetHealth": {
                "State": "healthy"
            }
        }
    ]
}

一旦我要执行的所有目标都获得JSON响应，如果条件仅当目标数目> 4并且所有目标都健康时才确保，那么请执行xyz ...所以说类似

if ( countoftarget >4 && alltargethasstate == healthy) then 
    echo "*****" 
else 
    sleep 2 minutes and keep checking the loop

是否有一种方法可以使用jq解析所有目标的状态值，并实现一个Shell脚本来执行此循环条件。

Answer 1

这里有个小片段，可以帮助您在没有jq的情况下实现这一目标。

HEALTHY_COUNT=`aws elbv2 --region us-east-1 describe-target-health --target-group-arn=******* \
--query 'TargetHealthDescriptions[?TargetHealth.State==\`healthy\`].[Target.Id]' --output text | wc -l`
echo $HEALTHY_COUNT

if [ $HEALTHY_COUNT -eq 1 ]; then
    echo "All izzz well!!!"
else 
    echo "Recheck how many healthy"
fi

这里有趣的部分是query，用于控制was cli的输出。请参见aws cli documentation，尤其是本节 “如何使用--query选项过滤输出”。查询选项基于此处介绍的JMESPath，在使用AWS CLI时非常漂亮。

Answer 2

在这里使用jq的潜在优势之一是，您可以轻松避免多次调用aws。

[.TargetHealthDescriptions[]
| select(.TargetHealth.State == "healthy")]
| . as $targets # in case you want to do something with them if the counting condition is satisfied
| length | if . > 4 then "found \(.) targets" else empty end

查询AWS ELB TARGET GROUP目标运行状况并根据某些条件执行功能

2 个答案: