Prevent outputing secrets to PS console

[sayedihashimi]

We should have a way to prevent secrets from getting displayed in the PS console. This can be achieved by overriding the PS output functions. The ones I can think of are:

• Output-Default
• Write-Output
• Write-Host
• Write-Debug
• Write-Error
• Write-Warning
• Write-Verbose

Here is a basic sample showing how to do this.

'executing test.ps1' | Write-Output


function Out-Default{
    [cmdletbinding(ConfirmImpact='Medium')]
    param(
        [Parameter(ValueFromPipeline=$true)]
        [System.Management.Automation.PSObject]$InputObject
    )
    begin{
        $wrappedObject = $ExecutionContext.InvokeCommand.GetCmdlet('Out-Default')
        $sb = { & $wrappedObject @PSBoundParameters }
        $__sp = $sb.GetSteppablePipeline()
        $__sp.Begin($pscmdlet)
    }
    process{
        $__sp.Process('***' + $_)
    }
    end{
        $__sp.End()
    }
}


function Write-Host{
    [cmdletbinding(ConfirmImpact='Medium')]
    param(
        [Parameter(ValueFromPipeline=$true)]
        [System.Management.Automation.PSObject]$InputObject
    )
    begin{
        $wrappedObject = $ExecutionContext.InvokeCommand.GetCmdlet('Write-Host')
        $sb = { & $wrappedObject @PSBoundParameters }
        $__sp = $sb.GetSteppablePipeline()
        $__sp.Begin($pscmdlet)
    }
    process{
        $__sp.Process('***' + $_)
    }
    end{
        $__sp.End()
    }
}


function Write-Output{
    [cmdletbinding(ConfirmImpact='Medium')]
    param(
        [Parameter(ValueFromPipeline=$true)]
        [System.Management.Automation.PSObject]$InputObject
    )
    begin{
        $wrappedObject = $ExecutionContext.InvokeCommand.GetCmdlet('Write-Host')
        $sb = { & $wrappedObject @PSBoundParameters }
        $__sp = $sb.GetSteppablePipeline()
        $__sp.Begin($pscmdlet)
    }
    process{
        $__sp.Process('***' + $_)
    }
    end{
        $__sp.End()
    }
}


'test' | out-default
'http://sedodream.com' | Out-Default
'foo'|Write-Output
'bar'|Write-Host

[sayedihashimi]

Here is a more generic example

'executing test.ps1' | Write-Output

$strOutputOverrideFnFormatStr = @'
    [cmdletbinding(ConfirmImpact='Medium')]
    param(
        [Parameter(ValueFromPipeline=$true)]
        [System.Management.Automation.PSObject]$InputObject
    )
    begin{
        $wrappedObject = $ExecutionContext.InvokeCommand.GetCmdlet('<name>')
        $sb = { & $wrappedObject @PSBoundParameters }
        $__sp = $sb.GetSteppablePipeline()
        $__sp.Begin($pscmdlet)
    }
    process{
        $__sp.Process('***' + $_)
    }
    end{
        $__sp.End()
    }
'@

$writeFunctionsToCreate = 'Out-Default','Write-Output','Write-Host','Write-Debug','Write-Error','Write-Warning','Write-Verbose'
$fnFormatStr = '${function:<fnname>} = ([scriptblock]::Create($strOutputOverrideFnFormatStr.Replace("<name>","<fnname>")))'
$writeFunctionsToCreate | % {
    $fnFormatStr.Replace('<fnname>',$_)|iex    
}

'out-default test' | out-default
'write-output test' | Write-Output
'write-host test' | Write-Host
'write-Debug test' | Write-Debug
'Write-Verbose test' | Write-Verbose
'write-warning test' | Write-Warning
'Write-Error' | Write-Error

[sayedihashimi]

Should be supported in c72a28f. Need to add unit tests.