将属性从对象传递给Stop-EC2Instance cmdlet时出错

Question

我正在编写一些用于通过名称标记而不是ID来启动和停止EC2实例的函数。首先我写了一个报告功能，可以在下面找到。

Function Get-EC2InstanceReport{ 
    If((Get-Module -Name AWSPowerShell).Name -ne 'AWSPowerShell'){ 
     Throw 'AWSPowerShell module is not loaded' 
    } 
    Get-EC2Tag | ` 
     Where-Object {$_.ResourceType -eq 'instance' -and $_.Key -eq 'Name'} | ` 
     Select-Object @{Name='InstanceID'; Expression={$_.ResourceID}}, @{Name='Name'; Expression={$_.Value}}, ` 
     @{Name='Status'; Expression={Get-EC2InstanceStatus -IncludeAllInstances $true -InstanceId $_.ResourceID | %  {$_.InstanceState.Name}}} 
} 

而且启动实例的函数没有错误地工作。

Function Start-EC2InstanceByName ([string]$Name){ 
    If((Get-Module -Name AWSPowerShell).Name -ne 'AWSPowerShell'){ 
     Throw 'AWSPowerShell module is not loaded' 
    } 
    [object]$EC2Instance = Get-EC2InstanceReport | Where-Object {$_.Name -eq $Name} 

    Try{ 
     If($EC2Instance[0].Status -eq 'stopped'){ 
      Start-EC2Instance -InstanceId $EC2Instance[0].InstanceId | Out-Null 
      Test-EC2InstanceStatus -Name $Name -EndState 'running' 
     } 
     Else{ 
      $ErrorMsg = "EC2 instance " + $EC2Instance[0].Name + " is not in the stopped state. It is " + $EC2Instance[0].Status + "." 
      Throw $ErrorMsg 
     } 
    } 
    Catch{ 
     $_ 
    } 
} 

但是，当使用类似的方法来停止实例时，我得到一个错误。

Function Stop-EC2InstanceByName ([string]$Name){ 
    If((Get-Module -Name AWSPowerShell).Name -ne 'AWSPowerShell'){ 
     Throw 'AWSPowerShell module is not loaded' 
    } 
    [object]$EC2Instance = Get-EC2InstanceReport | Where-Object {$_.Name -eq $Name} 

    Try{ 
     If($EC2Instance[0].Status -eq 'running'){ 
      Stop-EC2Instance -Instance $EC2Instance[0].InstanceID | Out-Null 
      Test-EC2InstanceStatus -Name $Name -EndState 'stopped' 
     } 
     Else{ 
      $ErrorMsg = "EC2 instance " + $EC2Instance[0].Name + " is not in the running state. It is " + $EC2Instance[0].Status + "." 
      Throw $ErrorMsg 
     } 
    } 
    Catch{ 
     $_ 
    } 
} 

该错误可以在下面找到。

Stop-EC2Instance : No instances specified 
At C:\GitProjects\DBA\aws-powershell-scripts\AWSFunctions.psm1:61 char:4 
+    Stop-EC2Instance -Instance $EC2Instance[0].InstanceID | Out-Null 
+    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 
    + CategoryInfo   : NotSpecified: (:) [Stop-EC2Instance], AmazonEC2Exception 
    + FullyQualifiedErrorId : Amazon.EC2.AmazonEC2Exception,Amazon.PowerShell.Cmdlets.EC2.StopEC2InstanceCmdlet 

任何帮助将不胜感激。如果您需要更多信息，请告诉我。

进一步进展。

权利，而不是解决为什么出现错误，并且有对AWS论坛在亚马逊https://forums.aws.amazon.com/thread.jspa?threadID=143319

但所期望的行为开放可以通过改变功能到低于被创建。

功能停止-EC2InstanceByName（[字符串] $名称）{ 如果（（GET-模块-Name AWSPowerShell）请将.Name -ne 'AWSPowerShell'）{ 掷 'AWSPowerShell模块没有装载' } [对象] $ EC2Instance = Get-EC2InstanceReport |位置对象{$ _。名称-eq $名称}

Try{ 
    If($EC2Instance[0].Status -eq 'running'){ 
     Get-EC2Instance -Filter @{Name="tag:Name"; Value=$Name} | Stop-EC2Instance | Out-Null 
     Test-EC2InstanceStatus -Name $Name -EndState 'stopped' 
    } 
    Else{ 
     $ErrorMsg = "EC2 instance " + $EC2Instance[0].Name + " is not in the running state. It is " + $EC2Instance[0].Status + "." 
     Throw $ErrorMsg 
    } 
} 
Catch{ 
$_ 
} 
} 

Answer 1

只需通过.ToString()转换得到了期望的结果对我来说，而无需经由管线通过输入。

# Failed attempt 
PS C:\> Stop-EC2Instance -Instance $myInstance.InstanceId 
Stop-EC2Instance : No instances specified 
At line:1 char:17 
+ Stop-EC2Instance <<<< -Instance $myInstance.InstanceId 
    + CategoryInfo   : NotSpecified: (:) [Stop-EC2Instance], AmazonEC2Exception 
    + FullyQualifiedErrorId : Amazon.EC2.AmazonEC2Exception,Amazon.PowerShell.Cmdlets.EC2.StopEC2InstanceCmdlet 

# Successful attempt 
PS C:\> Stop-EC2Instance -Instance $myInstance.InstanceId.ToString() 
# Goodnight instance... 

这是...奇怪，因为当我们的实例对象上使用Get-Member我们可以看到，在实例id定义有一个字符串：

TypeName: Selected.Amazon.EC2.Model.ResourceTag 

Name  MemberType Definition 
----  ---------- ---------- 
Equals  Method  bool Equals(System.Object obj) 
GetHashCode Method  int GetHashCode() 
GetType  Method  type GetType() 
ToString Method  string ToString() 
InstanceID NoteProperty System.String InstanceID=i-abcd1234 
Name  NoteProperty System.String Name=MyInstance 
Status  NoteProperty Status=null 

传递通过管道输入的实例id工作，因为它可以接受System.Object[]，而这似乎明确使用-Instance宁愿使用字符串实例ID。 Stop-EC2Instance documentation corroborates this：

-Instance <Object[]> 
Identifies the set of instances to stop or terminate. Accepts a string instance ID or a collection of RunningInstance or Reservation objects. If a Reservation object is supplied, all of the instances in the reservation are processed. 
Required? False 
Position? 1 
Accept pipeline input? True (ByValue,) 

Answer 2

盟友，

我相信你已经在你的语法有错误停止。

你的启动命令（工作）：

Start-EC2Instance -InstanceId $EC2Instance[0].InstanceId 

你停止命令（不工作）：

Stop-EC2Instance -Instance $EC2Instance[0].InstanceID 

尝试更新 '-instance' 标志 '-InstanceId'，看看它是如何去。 :-)

-Tim

Answer 3

没事，为什么会出现错误并有对AWS论坛在亚马逊https://forums.aws.amazon.com/thread.jspa?threadID=143319

但所期望的行为开放可以通过改变函数来创建未解决下面。

Function Stop-EC2InstanceByName ([string]$Name){ 
    If((Get-Module -Name AWSPowerShell).Name -ne 'AWSPowerShell'){ 
     Throw 'AWSPowerShell module is not loaded' 
    } 
    [object]$EC2Instance = Get-EC2InstanceReport | Where-Object {$_.Name -eq $Name} 

    Try{ 
     If($EC2Instance[0].Status -eq 'running'){ 
      Get-EC2Instance -Filter @{Name="tag:Name"; Value=$Name} | Stop-EC2Instance | Out-Null 
      Test-EC2InstanceStatus -Name $Name -EndState 'stopped' 
     } 
     Else{ 
      $ErrorMsg = "EC2 instance " + $EC2Instance[0].Name + " is not in the running state. It is " + $EC2Instance[0].Status + "." 
      Throw $ErrorMsg 
     } 
    } 
    Catch{ 
    $_ 
    } 
}