Public/Get-PSCFNStackOutputs.ps1
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function Get-PSCFNStackOutputs { <# .SYNOPSIS Get the outputs of a stack in various formats .DESCRIPTION This function can be used to assist creation of new CloudFormation templates that refer to the outputs of another stack. It can be used to generate either mapping or prarameter blocks based on these outputs by converting the returned object to JSON or YAML .PARAMETER StackName One or more stacks to process. One object is produced for each stack .PARAMETER AsHashtable If set (default), returned object is a hashtable - key/value pairs for each stack output. .PARAMETER AsMappingBlock If set (default), returned object is formatted as a CloudFomration mapping block. Converting the output to JSON or YAML renders text that can be pasted within a Mappings declararion. .PARAMETER AsParameterBlock If set, returned object is formatted as a CloudFormation parameter block. Converting the output to JSON or YAML renders text that can be pasted within a Parameters declararion. .PARAMETER AsCrossStackReferences If set, returned object is formatted as a set of Fn::ImportValue statements, with any text matching the stack name within the output's ExportName being replaced with a placeholder generated from the stack name with the word 'Stack' appended. Make this a parameter to your new stack. Whilst the result converted to JSON is not much use as it is, the individual elements can be copied and pasted in where an Fn::ImportValue for that parameter would be used. YAML is not currently supported for this operation. .INPUTS [System.String[]] - You can pipe stack names or ARNs to this function .OUTPUTS [PSObject] - An object dependent on the setting of the above switches. Pipe the output to ConvertTo-Json or ConvertTo-Yaml .EXAMPLE Get-PSCFNStackOutputs -StackName MyStack -AsMappingBlock When converted to JSON or YAML, can be pasted into the Mapping declaration of another template .EXAMPLE Get-PSCFNStackOutputs -StackName MyStack -AsParameterBlock When converted to JSON or YAML, can be pasted into the Parameters declaration of another template .EXAMPLE Get-PSCFNStackOutputs -StackName MyStack -AsCrossStackReferences When converted to JSON or YAML, provides a collection of Fn::Import stanzas that can be individually pasted into a new template .EXAMPLE $hash = Get-PSCFNStackOutputs -StackName MyStack -AsHashtable Returns hashtable of output key vs output value #> [CmdletBinding(DefaultParameterSetName = 'Hash')] param ( [Parameter(Mandatory = $true, ValueFromPipeline = $true, ValueFromPipelineByPropertyName = $true, Position = 0)] [string[]]$StackName, [Parameter(ParameterSetName = 'Hash')] [switch]$AsHashtable, [Parameter(ParameterSetName = 'Mappings')] [switch]$AsMappingBlock, [Parameter(ParameterSetName = 'Parameters')] [switch]$AsParameterBlock, [Parameter(ParameterSetName = 'Exports')] [switch]$AsCrossStackReferences ) DynamicParam { #Create the RuntimeDefinedParameterDictionary New-Object System.Management.Automation.RuntimeDefinedParameterDictionary | New-CredentialDynamicParameters } begin { $credentialArguments = Get-CommonCredentialParameters -CallerBoundParameters $PSBoundParameters } process { $StackName | ForEach-Object { if (Test-StackExists -StackName $_ -CredentialArguments $credentialArguments) { $ti = New-Object System.Globalization.CultureInfo ("en-US") # Explicit char casts or .net core gets it wrong $stackParam = ($_.Split([char]'_', [char]'-') | Foreach-Object { $ti.TextInfo.ToTitleCase($_) }) -join [string]::Empty $outputs = @{} $stack = Get-CFNStack -StackName $_ @credentialArguments $stack.Outputs | ForEach-Object { if ($AsParameterBlock) { $param = @{ Type = Get-ParameterTypeFromStringValue -Value $_.OutputValue Default = $_.OutputValue } if (-not [string]::IsNullOrEmpty($_.Description)) { $param.Add('Description', $_.Description) } $outputs.Add($_.OutputKey, $param) } elseif ($AsCrossStackReferences) { if (-not [string]::IsNullOrEmpty($_.ExportName)) { $param = @{ 'Fn::ImportValue' = @{ 'Fn::Sub' = $_.ExportName.Replace($stack.StackName, "`${$($stackparam)Stack}") } } $outputs.Add($_.OutputKey, $param) } } else { $outputs.Add($_.OutputKey, $_.OutputValue) } } if ($outputs.Count -gt 0) { if ($AsHashtable) { # Just emit the hashtable $outputs } else { # Emit outputs as object New-Object PSObject -Property $outputs } } } } } } |