Question

我尝试将JSON文件提取到Powershell中，将JSON块附加到现有节点（Components），然后将PSCustomObject转换回JSON并保存文件。我玩的JSON看起来像图1。

正如您在我的代码中看到的，我运行ConvertTo-Json将数据转换为PSCustomObject，然后我将一个新对象附加到Components节点。如果我查看对象，在这种情况下$ configFile看起来都很好，但是当我将组件节点中的项目转换回JSON时，将被视为字符串而不是评估为JSON（请参阅最后一个片段）。我想这是因为ConvertTo-JSON按字面意思处理数组，但不是100％肯定。

如果有人可以建议如何确保组件节点中的PSCustomObjects正确地返回到JSON，我将不胜感激，谢谢。

图1 - 原始JSON：

{
"EngineConfiguration": {
    "PollInterval": "00:00:15",
    "Components": [
        {
            "Id": "ApplicationEventLog",
            "FullName": "AWS.EC2.Windows.CloudWatch.EventLog.EventLogInputComponent,AWS.EC2.Windows.CloudWatch",
            "Parameters": {
                "LogName": "Application",
                "Levels": "1"
            }
        },
        {
            "Id": "SystemEventLog",
            "FullName": "AWS.EC2.Windows.CloudWatch.EventLog.EventLogInputComponent,AWS.EC2.Windows.CloudWatch",
            "Parameters": {
                "LogName": "System",
                "Levels": "7"
            }
        }
    ],
    "Flows": {
        "Flows": 
        [
            "(ApplicationEventLog,SystemEventLog),CloudWatchLogs"
        ]
    }
} 
}

图2 - 我的代码：

#Requires -Version 3.0

$configFile = "C:\Program Files\Amazon\EC2ConfigService\Settings\AWS.EC2.Windows.CloudWatch.json"
$configToPSObject = ConvertFrom-Json "$(Get-Content $configFile)"

$configToPSObject.EngineConfiguration.Components += New-Object -Type PSObject -Property ([ordered]@{
"Id" = "IISRequestQueueSize"
"FullName" = "AWS.EC2.Windows.CloudWatch.PerformanceCounterComponent.PerformanceCounterInputComponent,AWS.EC2.Windows.CloudWatch"
"Parameters" = [PSCustomObject]@{
        "CategoryName" = "HTTP Service Request Queues"
        "CounterName" = "CurrentQueueSize"
        "InstanceName" = "_Total"
        "MetricName" = "IISRequestQueueSize"
        "Unit" = ""
        "DimensionName" = ""
        "DimensionValue" = ""
}
})

$configJson = ConvertTo-Json -Depth 5 $configToPSObject


Set-Content -Path $configFile -Value $configJson

图3 - JSON输出：

{
"EngineConfiguration":  {
    "PollInterval":  "00:00:15",
    "Components":  [
        "@{Id=ApplicationEventLog; FullName=AWS.EC2.Windows.CloudWatch.EventLog.EventLogInputComponent,AWS.EC2.Windows.CloudWatch; Parameters=}",
        "@{Id=SystemEventLog; FullName=AWS.EC2.Windows.CloudWatch.EventLog.EventLogInputComponent,AWS.EC2.Windows.CloudWatch; Parameters=}",
        "@{Id=IISRequestQueueSize; FullName=AWS.EC2.Windows.CloudWatch.PerformanceCounterComponent.PerformanceCounterInputComponent,AWS.EC2.Windows.CloudWatch; Parameters=}"
        ],
"Flows":  {
    "Flows": 
        "(ApplicationEventLog,SystemEventLog),CloudWatchLogs"
    }
}
}

如果我将深度增加到8或更高，则JSON如下：

{
"EngineConfiguration":  {
   "PollInterval":  "00:00:15",
   "Components":  [
       "@{Id=ApplicationEventLog; FullName=AWS.EC2.Windows.CloudWatch.EventLog.EventLogInputComponent,AWS.EC2.Windows.CloudWatch; Parameters=}",
       "@{Id=SystemEventLog; FullName=AWS.EC2.Windows.CloudWatch.EventLog.EventLogInputComponent,AWS.EC2.Windows.CloudWatch; Parameters=}",
       "Id":  "IISRequestQueueSize",
       "FullName":  "AWS.EC2.Windows.CloudWatch.PerformanceCounterComponent.PerformanceCounterInputComponent,AWS.EC2.Windows.CloudWatch",
       "Parameters":  {                                                                        
           "CategoryName":  "HTTP Service Request Queues",
           "CounterName":  "CurrentQueueSize",
           "InstanceName":  "_Total",                                                                      
           "MetricName":  "IISRequestQueueSize",
           "Unit":  "",
           "DimensionName":  "",
           "DimensionValue":  ""
        }
    }
],
"Flows":  {
    "Flows":  "(ApplicationEventLog,SystemEventLog),CloudWatchLogs"
    }
}
}

Answer 1

ConvertTo-Json cmdlet还有一个Depth参数，超出该参数，对象将被toString()处理，而不是更深入地进行递归。因此，只需将该参数设置为您拥有的任何最大对象深度，都应该生成正确形成的JSON。

$configJson = ConvertTo-Json $configToPSObject -Depth 8 
# your JSON has depth of 5, get some extra

Answer 2

您必须提供ConvertTo-Json命令行开关的深度。否则它只执行第一级并按原样保留子节点并显然将它们转换为字符串。

$configJson = ConvertTo-Json $obj -Depth 3

无法正确地将数组中的PSCustomObjects转换回JSON

2 个答案: