[HorizonAPI]Powershell Script to push a new Desktop image using the REST api.

I already blogged about pushing a new image using the Python module for Horizon but I decided it was time to also have a reusable script that is able to push a new image using powershell and the rest api for Horizon. The script that I created has 10(!) arguments of which 6 are required:

  • ConnectionServerURL: https://server.domain.dom
  • vCenterURL: https://vcenter.domain.dom
  • DataCenterName: Name of the datacenter the source VM resides in
  • BaseVMName : name of the source VM
  • BaseSnapShotName: name of the source Snapshot
  • DesktopPoolName: name of the source Desktop Pool to apply the snapshot to

The datacenter name is required as that’s an requirement to grab the Source VM details.

The optional arguments are:

  • Credentials: PSCRedential object (get-credential for example) when not provided it will ask for user and password. The user should also contain the domain i.e. domain\user
  • StoponError: $true or $false depending on if you want to stop on errors, defaults to $true if not provided
  • logoff_policy: Optional WAIT_FOR_LOGOFF or FORCE_LOGOFF depending on the logoff policy you want
  • Scheduledtime: [DateTime] object in case you want to push for the future

The script itself was fairly easy to create, from the api explorer it was easy what id’s I needed and it was a matter of working back so I had all of them. In the end the hardest part was getting the scheduling to work. I used the (standard?) 10 digit epoch that most people use but it turns out that VMware wanted to schedule it very exactly in milliseconds! For the rest I used the well known functions for authentication but not my generic function for filtering or pagination as almost none of the api calls I use in this script support that.

<#
    .SYNOPSIS
    Pushes a new Golden Image to a Desktop Pool

    .DESCRIPTION
    This script uses the Horizon rest api's to push a new golden image to a VMware Horizon Desktop Pool

    .EXAMPLE
    .\Horizon_Rest_Push_Image.ps1 -ConnectionServerURL https://pod1cbr1.loft.lab -Credentials $creds -vCenterURL "https://pod1vcr1.loft.lab" -DataCenterName "Datacenter_Loft" -baseVMName "W21h1-2021-09-08-15-48" -BaseSnapShotName "Demo Snapshot" -DesktopPoolName "Pod01-Pool02"

    .PARAMETER Credential
    Mandatory: No
    Type: PSCredential
    Object with credentials for the connection server with domain\username and password. If not supplied the script will ask for user and password.

    .PARAMETER ConnectionServerURL
    Mandatory: Yes
    Default: String
    URL of the connection server to connect to

    .PARAMETER vCenterURL
    Mandatory: Yes
    Username of the user to look for

    .PARAMETER DataCenterName
    Mandatory: Yes
    Domain to look in

    .PARAMETER BaseVMName
    Mandatory: Yes
    Domain to look in

    .PARAMETER BaseSnapShotName
    Mandatory: Yes
    Domain to look in

    .PARAMETER DesktopPoolName
    Mandatory: Yes
    Domain to look in

    .PARAMETER StoponError
    Mandatory: No
    Boolean to stop on error or not

    .PARAMETER logoff_policy
    Mandatory: No
    String FORCE_LOGOFF or WAIT_FOR_LOGOFF to set the logoff policy.

    .PARAMETER Scheduledtime
    Mandatory: No
    Time to schedule the image push in [DateTime] format.

    .NOTES
    Minimum required version: VMware Horizon 8 2012
    Created by: Wouter Kursten
    First version: 03-11-2021

    .COMPONENT
    Powershell Core
#>

[CmdletBinding()]
param (
    [Parameter(Mandatory=$false,
    HelpMessage='Credential object as domain\username with password' )]
    [PSCredential] $Credentials,

    [Parameter(Mandatory=$true,  HelpMessage='FQDN of the connectionserver' )]
    [ValidateNotNullOrEmpty()]
    [string] $ConnectionServerURL,

    [parameter(Mandatory = $true,
    HelpMessage = "URL of the vCenter to look in i.e. https://vcenter.domain.lab")]
    [ValidateNotNullOrEmpty()]
    [string]$vCenterURL,

    [parameter(Mandatory = $true,
    HelpMessage = "Name of the Datacenter to look in.")]
    [ValidateNotNullOrEmpty()]
    [string]$DataCenterName,

    [parameter(Mandatory = $true,
    HelpMessage = "Name of the Golden Image VM.")]
    [ValidateNotNullOrEmpty()]
    [string]$BaseVMName,

    [parameter(Mandatory = $true,
    HelpMessage = "Name of the Snapshot to use for the Golden Image.")]
    [ValidateNotNullOrEmpty()]
    [string]$BaseSnapShotName,

    [parameter(Mandatory = $true,
    HelpMessage = "Name of the Desktop Pool.")]
    [ValidateNotNullOrEmpty()]
    [string]$DesktopPoolName,

    [parameter(Mandatory = $false,
    HelpMessage = "Name of the Desktop Pool.")]
    [ValidateNotNullOrEmpty()]
    [bool]$StoponError = $true,

    [parameter(Mandatory = $false,
    HelpMessage = "Name of the Desktop Pool.")]
    [ValidateSet('WAIT_FOR_LOGOFF','FORCE_LOGOFF', IgnoreCase = $false)]
    [string]$logoff_policy = "WAIT_FOR_LOGOFF",

    [parameter(Mandatory = $false,
    HelpMessage = "DateTime object for the moment of scheduling the image push.Defaults to immediately")]
    [datetime]$Scheduledtime
)
if($Credentials){
    $username=($credentials.username).split("\")[1]
    $domain=($credentials.username).split("\")[0]
    $password=$credentials.password
}
else{
    $credentials = Get-Credential
    $username=($credentials.username).split("\")[1]
    $domain=($credentials.username).split("\")[0]
    $password=$credentials.password
}

$BSTR = [System.Runtime.InteropServices.Marshal]::SecureStringToBSTR($password) 
$UnsecurePassword = [System.Runtime.InteropServices.Marshal]::PtrToStringAuto($BSTR)

function Get-HRHeader(){
    param($accessToken)
    return @{
        'Authorization' = 'Bearer ' + $($accessToken.access_token)
        'Content-Type' = "application/json"
    }
}
function Open-HRConnection(){
    param(
        [string] $username,
        [string] $password,
        [string] $domain,
        [string] $url
    )

    $Credentials = New-Object psobject -Property @{
        username = $username
        password = $password
        domain = $domain
    }

    return invoke-restmethod -Method Post -uri "$ConnectionServerURL/rest/login" -ContentType "application/json" -Body ($Credentials | ConvertTo-Json)
}
function Close-HRConnection(){
    param(
        $accessToken,
        $ConnectionServerURL
    )
    return Invoke-RestMethod -Method post -uri "$ConnectionServerURL/rest/logout" -ContentType "application/json" -Body ($accessToken | ConvertTo-Json)
}

try{
    $accessToken = Open-HRConnection -username $username -password $UnsecurePassword -domain $Domain -url $ConnectionServerURL
}
catch{
    throw "Error Connecting: $_"
}

$vCenters = Invoke-RestMethod -Method Get -uri "$ConnectionServerURL/rest/monitor/v2/virtual-centers" -ContentType "application/json" -Headers (Get-HRHeader -accessToken $accessToken)
$vcenterid = ($vCenters | where-object {$_.name -like "*$vCenterURL*"}).id
$datacenters = Invoke-RestMethod -Method Get -uri "$ConnectionServerURL/rest/external/v1/datacenters?vcenter_id=$vcenterid" -ContentType "application/json" -Headers (Get-HRHeader -accessToken $accessToken)
$datacenterid = ($datacenters | where-object {$_.name -eq $DataCenterName}).id
$basevms = Invoke-RestMethod -Method Get -uri "$ConnectionServerURL/rest/external/v1/base-vms?datacenter_id=$datacenterid&filter_incompatible_vms=false&vcenter_id=$vcenterid" -ContentType "application/json" -Headers (Get-HRHeader -accessToken $accessToken)
$basevmid = ($basevms | where-object {$_.name -eq $baseVMName}).id
$basesnapshots = Invoke-RestMethod -Method Get -uri "$ConnectionServerURL/rest/external/v1/base-snapshots?base_vm_id=$basevmid&vcenter_id=$vcenterid" -ContentType "application/json" -Headers (Get-HRHeader -accessToken $accessToken)
$basesnapshotid = ($basesnapshots | where-object {$_.name -eq $BaseSnapShotName}).id
$desktoppools = Invoke-RestMethod -Method Get -uri "$ConnectionServerURL/rest/inventory/v1/desktop-pools" -ContentType "application/json" -Headers (Get-HRHeader -accessToken $accessToken)
$desktoppoolid = ($desktoppools | where-object {$_.name -eq $DesktopPoolName}).id
$startdate = (get-date -UFormat %s)
$datahashtable = [ordered]@{}
$datahashtable.add('logoff_policy',$logoff_policy)
$datahashtable.add('parent_vm_id',$basevmid)
$datahashtable.add('snapshot_id',$basesnapshotid)
if($Scheduledtime){
    $starttime = get-date $Scheduledtime
    $epoch = ([DateTimeOffset]$starttime).ToUnixTimeMilliseconds()
    $datahashtable.add('start_time',$epoch)
}

$datahashtable.add('stop_on_first_error',$StoponError)
$json = $datahashtable | convertto-json
Invoke-RestMethod -Method Post -uri "$ConnectionServerURL/rest/inventory/v1/desktop-pools/$desktoppoolid/action/schedule-push-image" -ContentType "application/json" -Headers (Get-HRHeader -accessToken $accessToken) -body $json

I use it like this for example:

D:\GIT\Various_Scripts\Horizon_Rest_Push_Image.ps1 -ConnectionServerURL https://pod1cbr1.loft.lab -vCenterURL "https://pod1vcr1.loft.lab" -DataCenterName "Datacenter_Loft" -baseVMName "W21h1-2021-09-08-15-48" -BaseSnapShotName "Demo Snapshot" -DesktopPoolName "Pod01-Pool01" -logoff_policy WAIT_FOR_LOGOFF -StoponError $true -Scheduledtime ((get-date).AddMinutes(75))

Except for the question for username and password (in this case) there’s no response

and the push image is scheduled 75 minutes in the future

As always the script itself is also available at Github HERE.

Next time I’ll add more error handling and update the script to also push images to RDS farms 🙂