New-PipeScript.ps1
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function New-PipeScript { <# .Synopsis Creates new PipeScript. .Description Creates new PipeScript and PowerShell ScriptBlocks. .EXAMPLE New-PipeScript -Parameter @{a='b'} #> [Alias('New-ScriptBlock')] param( # Defines one or more parameters for a ScriptBlock. # Parameters can be defined in a few ways: # * As a ```[Collections.Dictionary]``` of Parameters # * As the ```[string]``` name of an untyped parameter. # * As a ```[ScriptBlock]``` containing only parameters. [Parameter(ValueFromPipelineByPropertyName)] [ValidateScript({ if ($_ -isnot [ScriptBlock]) { return $true } $statementCount = 0 $statementCount += $_.Ast.DynamicParamBlock.Statements.Count $statementCount += $_.Ast.BeginBlock.Statements.Count $statementCount += $_.Ast.ProcessBlock.Statements.Count $statementCount += $_.Ast.EndBlock.Statements.Count if ($statementCount) { throw "ScriptBlock should have no statements" } else { return $true } })] [ValidateScript({ $validTypeList = [System.Collections.IDictionary],[System.String],[System.Object[]],[System.Management.Automation.ScriptBlock] $thisType = $_.GetType() $IsTypeOk = $(@( foreach ($validType in $validTypeList) { if ($_ -as $validType) { $true;break } })) if (-not $isTypeOk) { throw "Unexpected type '$(@($thisType)[0])'. Must be 'System.Collections.IDictionary','string','System.Object[]','scriptblock'." } return $true })] $Parameter, # The dynamic parameter block. [Parameter(ValueFromPipelineByPropertyName)] [ValidateScript({ if ($_ -isnot [ScriptBlock]) { return $true } if ($_.Ast.DynamicParamBlock -or $_.Ast.BeginBlock -or $_.Ast.ProcessBlock) { throw "ScriptBlock should not have any named blocks" } return $true })] [ValidateScript({ if ($_ -isnot [ScriptBlock]) { return $true } if ($_.Ast.ParamBlock.Parameters.Count) { throw "ScriptBlock should not have parameters" } return $true })] [Alias('DynamicParameterBlock')] [ScriptBlock] $DynamicParameter, # The begin block. [Parameter(ValueFromPipelineByPropertyName)] [ValidateScript({ if ($_ -isnot [ScriptBlock]) { return $true } if ($_.Ast.DynamicParamBlock -or $_.Ast.BeginBlock -or $_.Ast.ProcessBlock) { throw "ScriptBlock should not have any named blocks" } return $true })] [ValidateScript({ if ($_ -isnot [ScriptBlock]) { return $true } if ($_.Ast.ParamBlock.Parameters.Count) { throw "ScriptBlock should not have parameters" } return $true })] [Alias('BeginBlock')] [ScriptBlock] $Begin, # The process block. [Parameter(ValueFromPipelineByPropertyName)] [ValidateScript({ if ($_ -isnot [ScriptBlock]) { return $true } if ($_.Ast.DynamicParamBlock -or $_.Ast.BeginBlock -or $_.Ast.ProcessBlock) { throw "ScriptBlock should not have any named blocks" } return $true })] [ValidateScript({ if ($_ -isnot [ScriptBlock]) { return $true } if ($_.Ast.ParamBlock.Parameters.Count) { throw "ScriptBlock should not have parameters" } return $true })] [Alias('ProcessBlock')] [ScriptBlock] $Process, # The end block. [Parameter(ValueFromPipelineByPropertyName)] [ValidateScript({ if ($_ -isnot [ScriptBlock]) { return $true } if ($_.Ast.DynamicParamBlock -or $_.Ast.BeginBlock -or $_.Ast.ProcessBlock) { throw "ScriptBlock should not have any named blocks" } return $true })] [ValidateScript({ if ($_ -isnot [ScriptBlock]) { return $true } if ($_.Ast.ParamBlock.Parameters.Count) { throw "ScriptBlock should not have parameters" } return $true })] [Alias('EndBlock')] [ScriptBlock] $End, # The script header. [Parameter(ValueFromPipelineByPropertyName)] [string] $Header, # If provided, will automatically create parameters. # Parameters will be automatically created for any unassigned variables. [Alias('AutoParameterize','AutoParameters')] [switch] $AutoParameter, # The type used for automatically generated parameters. # By default, ```[PSObject]```. [type] $AutoParameterType = [PSObject] ) begin { $ParametersToCreate = [Ordered]@{} $parameterScriptBlocks = @() $allDynamicParameters = @() $allBeginBlocks = @() $allEndBlocks = @() $allProcessBlocks = @() $allHeaders = @() } process { if ($parameter) { # The -Parameter can be a dictionary of parameters. if ($Parameter -is [Collections.IDictionary]) { $parameterType = '' # If it is, walk thur each parameter in the dictionary foreach ($EachParameter in $Parameter.GetEnumerator()) { # Continue past any parameters we already have if ($ParametersToCreate.Contains($EachParameter.Key)) { continue } # If the parameter is a string and the value is not a variable if ($EachParameter.Value -is [string] -and $EachParameter.Value -notlike '*$*') { $parameterName = $EachParameter.Key $ParametersToCreate[$EachParameter.Key] = @( $parameterAttribute = "[Parameter(ValueFromPipelineByPropertyName)]" $parameterType '$' + $parameterName ) -ne '' } # If the value is a string and the value contains variables elseif ($EachParameter.Value -is [string]) { # embed it directly. $ParametersToCreate[$EachParameter.Key] = $EachParameter.Value } # If the value is a ScriptBlock elseif ($EachParameter.Value -is [ScriptBlock]) { # Embed it $ParametersToCreate[$EachParameter.Key] = # If there was a param block on the script block if ($EachParameter.Value.Ast.ParamBlock) { # embed the parameter block (except for the param keyword) $EachParameter.Value.Ast.ParamBlock.Extent.ToString() -replace '^[\s\r\n]{0,}param\(' -replace '\)[\s\r\n]{0,}$' } else { # Otherwise '[Parameter(ValueFromPipelineByPropertyName)]' + ( $EachParameter.Value.ToString() -replace "\`$$($eachParameter.Key)[\s\r\n]$" -replace # Replace any trailing variables 'param\(\)[\s\r\n]{0,}$' # then replace any empty param blocks. ) } } # If the value was an array elseif ($EachParameter.Value -is [Object[]]) { $ParametersToCreate[$EachParameter.Key] = # join it's elements by newlines $EachParameter.Value -join [Environment]::Newline } } } # If the parameter was a string elseif ($Parameter -is [string]) { # treat it as parameter name $ParametersToCreate[$Parameter] = @( "[Parameter(ValueFromPipelineByPropertyName)]" "`$$Parameter" ) -join [Environment]::NewLine } # If the parameter is a [ScriptBlock] elseif ($parameter -is [scriptblock]) { # add it to a list of parameter script blocks. $parameterScriptBlocks += if ($parameter.Ast.ParamBlock) { $parameter } } } # If there is header content, if ($header) { $allHeaders += $Header } # dynamic parameters, if ($DynamicParameter) { $allDynamicParameters += $DynamicParameter } # begin, if ($Begin) { $allBeginBlocks += $begin } # process, if ($process) { $allProcessBlocks += $process } # or end blocks. if ($end) { # accumulate them. $allEndBlocks += $end } if ($AutoParameter) { $variableDefinitions = $Begin, $Process, $End | Where-Object { $_ } | Search-PipeScript -AstType VariableExpressionAST | Select-Object -ExpandProperty Result foreach ($var in $variableDefinitions) { $assigned = $var.GetAssignments() if ($assigned) { continue } $varName = $var.VariablePath.userPath.ToString() $ParametersToCreate[$varName] = @( @( "[Parameter(ValueFromPipelineByPropertyName)]" "[$($AutoParameterType.FullName -replace '^System\.')]" "$var" ) -join [Environment]::NewLine ) } } } end { # Take all of the accumulated parameters and create a parameter block $newParamBlock = "param(" + [Environment]::newLine + $(@(foreach ($toCreate in $ParametersToCreate.GetEnumerator()) { $toCreate.Value -join [Environment]::NewLine }) -join (',' + [Environment]::NewLine)) + [Environment]::NewLine + ')' # If any parameters were passed in as ```[ScriptBlock]```s, if ($parameterScriptBlocks) { $parameterScriptBlocks += [ScriptBlock]::Create($newParamBlock) # join them with the new parameter block. $newParamBlock = $parameterScriptBlocks | Join-PipeScript } # Create the script block by combining together the provided parts. $createdScriptBlock = [scriptblock]::Create(" $($allHeaders -join [Environment]::Newline) $newParamBlock $(if ($allDynamicParameters) { @(@("dynamicParam {") + $allDynamicParameters + '}') -join [Environment]::Newline }) $(if ($allBeginBlocks) { @(@("begin {") + $allBeginBlocks + '}') -join [Environment]::Newline }) $(if ($allProcessBlocks) { @(@("process {") + $allProcessBlocks + '}') -join [Environment]::Newline }) $(if ($allEndBlocks -and -not $allBeginBlocks -and -not $allProcessBlocks) { $allEndBlocks -join [Environment]::Newline } elseif ($allEndBlocks) { @(@("end {") + $allEndBlocks + '}') -join [Environment]::Newline }) ") # return the created script block. return $createdScriptBlock } } |