DscResources/Carbon_ScheduledTask/Carbon_ScheduledTask.psm1
# Licensed under the Apache License, Version 2.0 (the "License"); # you may not use this file except in compliance with the License. # You may obtain a copy of the License at # # http://www.apache.org/licenses/LICENSE-2.0 # # Unless required by applicable law or agreed to in writing, software # distributed under the License is distributed on an "AS IS" BASIS, # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. # See the License for the specific language governing permissions and # limitations under the License. & (Join-Path -Path $PSScriptRoot -ChildPath '..\Initialize-CarbonDscResource.ps1' -Resolve) function Get-TargetResource { [CmdletBinding()] [OutputType([hashtable])] param( [Parameter(Mandatory=$true)] [ValidateLength(1,238)] [Alias('TaskName')] [string] # The name of the scheduled task to return. Wildcards supported. This must be the *full task name*, i.e. the task's path/location and its name. $Name, [string] # Install the task from this XML. $TaskXml, [Management.Automation.PSCredential] # The principal the task should run as. Use `Principal` parameter to run as a built-in security principal. Required if `Interactive` or `NoPassword` switches are used. $TaskCredential, [ValidateSet('Present','Absent')] [string] # If `Present`, the service is installed/updated. If `Absent`, the service is removed. $Ensure = 'Present' ) Set-StrictMode -Version 'Latest' $resource = @{ Name = $Name; TaskXml = ''; TaskCredential = $null; Ensure = 'Absent'; } if( (Test-ScheduledTask -Name $Name) ) { $task = Get-ScheduledTask -Name $Name $resource.TaskCredential = $task.RunAsUser $resource.TaskXml = schtasks.exe /query /xml /tn $Name | Where-Object { $_ } $resource.TaskXml = $resource.TaskXml -join ([Environment]::NewLine) $resource.Ensure = 'Present' } return $resource } function Set-TargetResource { <# .SYNOPSIS DSC resource for configuring scheduled tasks. .DESCRIPTION The `Carbon_ScheduledTask` resource configures scheduled tasks using `schtasks.exe` with [Task Scheduler XML](http://msdn.microsoft.com/en-us/library/windows/desktop/aa383609.aspx). The task is installed when the `Ensure` property is set to `Present`. If the task already exists, and the XML of the current task doesn't match the XML passed in, the task is deleted, and a new task is created in its place. The XML comparison is pretty dumb: it compares the XML document(s) as a giant string, not element by element. This means if your XML doesn't order elements in the same way as `schtasks.exe /query /xml`, then your task will always be deleted and re-created. This may or may not be a problem for you. `Carbon_ScheduledTask` is new in Carbon 2.0. .LINK Get-ScheduledTask .LINK Install-ScheduledTask .LINK Test-ScheduledTask .LINK Uninstall-ScheduledTask .LINK http://technet.microsoft.com/en-us/library/cc725744.aspx#BKMK_create .LINK http://msdn.microsoft.com/en-us/library/windows/desktop/aa383609.aspx .EXAMPLE > Demonstrates how to install a new or update an existing scheduled task that runs as a built-in user. The user's SID should be declared in the task XML file. Carbon_ScheduledTask InstallScheduledTask { Name = 'ClearApplicationCache'; TaskXml = (Get-Content -Path $clearApplicationCacheTaskPath.xml -Raw); } .EXAMPLE > Demonstrates how to install a new or update an existing scheduled task that runs as a custom user. Carbon_ScheduledTask InstallScheduledTask { Name = 'ClearApplicationCache'; TaskXml = (Get-Content -Path $clearApplicationCacheTaskPath.xml -Raw); TaskCredential = (Get-Credential 'runasuser'); } .EXAMPLE > Demonstrates how to remove a scheduled task. Carbon_ScheduledTask InstallScheduledTask { Name = 'ClearApplicationCache'; Ensure = 'Absent'; } #> [CmdletBinding()] param( [Parameter(Mandatory=$true)] [ValidateLength(1,238)] [Alias('TaskName')] [string] # The name of the scheduled task to return. Wildcards supported. This must be the *full task name*, i.e. the task's path/location and its name. $Name, [string] # Install the task from this XML. $TaskXml, [Management.Automation.PSCredential] # The principal the task should run as. Use `Principal` parameter to run as a built-in security principal. Required if `Interactive` or `NoPassword` switches are used. $TaskCredential, [ValidateSet('Present','Absent')] [string] # If `Present`, the service is installed/updated. If `Absent`, the service is removed. $Ensure = 'Present' ) Set-StrictMode -Version 'Latest' $PSBoundParameters.Remove('Ensure') if( $Ensure -eq 'Present' ) { $installParams = @{ } if( (Test-ScheduledTask -Name $Name ) ) { Write-Verbose ('[{0}] Re-installing' -f $Name) $installParams['Force'] = $true } else { Write-Verbose ('[{0}] Installing' -f $Name) } Install-ScheduledTask @PSBoundParameters @installParams } else { Write-Verbose ('[{0}] Uninstalling' -f $Name) Uninstall-ScheduledTask -Name $Name } } function Test-TargetResource { [CmdletBinding(SupportsShouldProcess=$true)] [OutputType([bool])] param( [Parameter(Mandatory=$true)] [ValidateLength(1,238)] [Alias('TaskName')] [string] # The name of the scheduled task to return. Wildcards supported. This must be the *full task name*, i.e. the task's path/location and its name. $Name, [string] # Install the task from this XML. $TaskXml, [Management.Automation.PSCredential] # The principal the task should run as. Use `Principal` parameter to run as a built-in security principal. Required if `Interactive` or `NoPassword` switches are used. $TaskCredential, [ValidateSet('Present','Absent')] [string] # If `Present`, the task is installed/updated. If `Absent`, the task is removed. $Ensure = 'Present' ) Set-StrictMode -Version 'Latest' $resource = Get-TargetResource -Name $Name if( $Ensure -eq 'Present' ) { if( $resource.Ensure -eq 'Absent' ) { Write-Verbose ('[{0}] Desired scheduled task not found' -f $Name) return $false } if( -not $TaskXml ) { Write-Error ('Property ''TaskXml'' is missing or empty. When creating a scheduled task, the ''TaskXml'' property is required.') return $true } $resourceXml = [xml]$resource.TaskXml $currentTaskXml = $resourceXml.OuterXml $desiredTaskXml = ([xml]$TaskXml).OuterXml if( $currentTaskXml -ne $desiredTaskXml ) { $differsAt = 0 for( $idx = 0; $idx -lt $desiredTaskXml.Length -and $idx -lt $currentTaskXml.Length; ++$idx ) { $charEqual = $desiredTaskXml[$idx] -eq $currentTaskXml[$idx] if( -not $charEqual ) { $differsAt = $idx break } } $nameLength = $Name.Length $linePrefix = ' ' * ($nameLength + 2) $msgFormat = @' '@ Write-Verbose ('[{0}] Task XML differs:' -f $Name) $startIdx = $differsAt - 35 if( $startIdx -lt 0 ) { $startIdx = 0 } $shortestLength = $currentTaskXml.Length if( $desiredTaskXml.Length -lt $shortestLength ) { $shortestLength = $desiredTaskXml.Length } $length = 70 if( $startIdx + $length -ge $shortestLength ) { $length = $shortestLength - $startIdx } Write-Verbose ('{0} Current {1}' -f $linePrefix,$currentTaskXml.Substring($startIdx,$length)) Write-Verbose ('{0} Desired {1}' -f $linePrefix,$desiredTaskXml.Substring($startIdx,$length)) if( $length -eq 70 ) { Write-Verbose ('{0} -----------------------------------^' -f $linePrefix) } return $false } else { Write-Verbose ('[{0}] Task XML unchanged' -f $Name) } if( $TaskCredential -and $resource.TaskCredential -ne $TaskCredential.UserName ) { Write-Verbose ('[{0}] [TaskCredential] {0} != {1}' -f $Name,$resource.TaskCredential,$TaskCredential.UserName) return $false } return $true } else { if( $resource.Ensure -eq 'Present' ) { Write-Verbose ('[{0}] Found' -f $Name) return $false } Write-Verbose ('[{0}] Not found' -f $Name) return $true } } Export-ModuleMember -Function * |