Public/Start-MyProcess.ps1
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function Start-MyProcess { <# .Synopsis Wraps up a call to execute a program using System.Diagnostics.Process. This allows us to redirect the stdout and stderr streams for better error handling. Specifcially this is used for quite a few MS utilities in our TFS build/deploy, as the utilities will usually throw warnings instead of terminating errors and we need to parse stdout to determine if there was an actuall error. .DESCRIPTION .EXAMPLE This example sets up a executable path, and options, then passes them to the function while captureing the returning stdout and stderr streams. Assume that $dacDinDir, $DestFile, $ConnectionString are all set to sueful values. $EXEPath = "$dacBinDir\SqlPackage.exe" $options = "/Action:Extract /OverwriteFiles:True /tf:$DestFile /scs:$ConnectionString" $return = Start-MyProcess -EXEPath $EXEPath -options $options if ($logLevel -eq "Debug"){ #Only show the stdout stream if we are in debugging logLevel $return.stdout } if ($return.sterr -ne $null){ Write-Log "$($return.sterr)" Warning Write-Log "There was an error of some type. See warning above for more info" Error } .OUTPUTS A object with 3 properties, stdout, stderr, and ExitCode. stdout and stderr are text streams that conatian output from the process. Generally if (stderr -eq $null) then there was some sort of error. You can also parse stdout to find errors, or check the ExitCode for non-success #> [CmdletBinding(SupportsShouldProcess=$true)] param( [Parameter(Position = 0)] [string]$EXEPath ,[Parameter(Position = 1)][string]$options ,[ValidateSet("Debug","Info","Warning","Error","Disable")] [string]$logLevel = "Warning" ,[switch]$async ,[int]$sleepTimer = 5 ,[string]$workingDir ) Get-CallerPreference -Cmdlet $PSCmdlet -SessionState $ExecutionContext.SessionState $currentLogLevel = Get-LogLevel if ([string]::IsNullOrEmpty($logLevel)) { $logLevel = "Warning" } Set-LogLevel $logLevel $EXE = $EXEPath.Substring($EXEPath.LastIndexOf("\") + 1,$EXEPath.Length - $EXEPath.LastIndexOf("\") - 1) $pinfo = New-Object System.Diagnostics.ProcessStartInfo $pinfo.FileName = "`"$EXEPath`"" $pinfo.Arguments = "$options" $pinfo.UseShellExecute = $false $pinfo.CreateNoWindow = $true if ([string]::IsNullOrEmpty($workingDir)) { $pinfo.WorkingDirectory = Get-Location } else { $pinfo.WorkingDirectory = $workingDir } $pinfo.RedirectStandardOutput = $true $pinfo.RedirectStandardError = $true # Create a process object using the startup info $process = New-Object System.Diagnostics.Process $process.StartInfo = $pinfo Write-Log "Executing the following command" Debug Write-Log "$($pinfo.FileName) $($pinfo.Arguments)" Debug try { $process.Start() | Out-Null } catch { Write-Log "****Process errors****" Warning Write-Log "$($_.Exception.ToString())" Warning Write-Log "Error calling $EXE. See previous warning(s) for error text. Try running the script with a lower logLevel variable to collect more troubleshooting information. Aborting script" Error -ErrorAction Stop } if (!$async) { if (!$process.HasExited) { # Wait a while for the process to exitn Write-Log "$EXE is not done, let's wait $sleepTimer more seconds" sleep -Seconds $sleepTimer } Write-Log "$EXE has completed." # get output from stdout and stderr $stdout = $process.StandardOutput.ReadToEnd() $stderr = $process.StandardError.ReadToEnd() $stdOutput = New-Object -TypeName PSObject $stdOutput | Add-Member –MemberType NoteProperty –Name stderr –Value $stderr $stdOutput | Add-Member –MemberType NoteProperty –Name stdout –Value $stdout $stdOutput | Add-Member -MemberType NoteProperty -Name exitCode -Value $process.ExitCode $returnVal = $stdOutput } else { $returnVal = $process } Set-LogLevel $currentLogLevel return $returnVal } Export-ModuleMember -Function Start-MyProcess |