omsAgent

1.3

functions/public/Install-omsDependencyAgent.ps1

#Requires -Version 5.0

function Install-OmsDependencyAgent
{
    <#
        .Synopsis
            Installs the OMS Dependency Agent on remote computers.
        .DESCRIPTION
            Either downloads the installer from a URL or copies the installer via the powershell session.
        .EXAMPLE
            Install-OmsDependencyAgent -sourcePath 'c:\MMASetup-AMD64.exe' -Verbose
        .NOTES
            Written by Ben Taylor
            Version 1.0, 22.06.2017
    #>
    [CmdletBinding(SupportsShouldProcess = $True, ConfirmImpact = 'Low', DefaultParameterSetName='downloadOMS')]
    [OutputType([String])]
    Param (
        [Parameter(Mandatory = $false, Position = 0, ValueFromPipeline=$True, valuefrompipelinebypropertyname=$true)]
        [ValidateNotNullOrEmpty()]
        [Alias('IPAddress', 'Name')]
        [string[]]
        $computerName = $env:COMPUTERNAME,
        [Parameter(ParameterSetName='downloadOMS')]
        [ValidateNotNullOrEmpty()]
        [string]
        $downloadURL = 'https://aka.ms/Dependencyagentwindows',
        [Parameter(ParameterSetName='localOMS')]
        [ValidateScript({Test-Path $_ })]
        [string]
        $sourcePath,
        [Parameter()]
        [System.Management.Automation.PSCredential]
        [System.Management.Automation.Credential()]
        $Credential
    )

    Begin
    {
        $commonSessionParams = @{
            ErrorAction = 'Stop'
        }

        If ($PSBoundParameters['Credential'])
        {
            $commonSessionParams.Credential = $Credential
        }
    }
    Process
    {
        forEach ($computer in $computerName)
        {
            try
            {
                Write-Verbose "[$(Get-Date -Format G)] - $computer - Creating Remote PS Session"
                $psSession = New-PSSession -ComputerName $computer -EnableNetworkAccess @commonSessionParams

                Write-Verbose "[$(Get-Date -Format G)] - $computer - Checking if OMS is Installed"
                    
                if(Get-omsAgentInternal -computerName $computer -session $psSession)
                {
                    If ($Pscmdlet.ShouldProcess($computer, 'Install OMS Dependency Agent'))
                    {
                         $path = Invoke-Command -Session $pssession -ScriptBlock {
                            $path = Join-Path $ENV:temp "DependencyAgent.exe"

                            # Check if file exists and if so remove
                            if(Test-Path $path)
                            {
                                Remove-Item $path -force -Confirm:$false
                            }

                            $path
                         }

                        if($PSBoundParameters.sourcePath -eq $true)
                        {
                            Write-Verbose "[$(Get-Date -Format G)] - $computer - Copying files over powershell session"
                            Copy-Item -Path $sourcePath -Destination (Split-path $path) -ToSession $psSession -Force
                        }
                        else
                        {
                            Write-Verbose "[$(Get-Date -Format G)] - $computer - Trying to download installer from URL - $downloadURL"
                            Invoke-Command -Session $psSession -ScriptBlock {
                                Invoke-WebRequest $USING:downloadURL -OutFile $USING:path -ErrorAction Stop | Out-Null
                            } -ErrorAction Stop
                        }


                        Write-Verbose "$computer - Trying to install OMS..."
                        $installString = $path + ' /S'

                        $installSuccess = Invoke-Command -Session $psSession -ScriptBlock {
                            cmd.exe /C $USING:installString
                            $LASTEXITCODE
                        } -ErrorAction Stop

                        if($installSuccess -ne 0)
                        {
                            Write-Error "$computer - OMS didn't install correctly based on the exit code"
                        }
                        else
                        {
                            if(Get-omsAgentInternal -computerName $computer -session $psSession)
                            {
                                Write-Verbose "[$(Get-Date -Format G)] - $computer - OMS Dependency Agent installed correctly"
                            }
                            else
                            {
                                Write-Error "[$(Get-Date -Format G)] - $computer - OMS Dependency Agent didn't install correctly based on the exit code"
                            }
                        }
                    }
                }
                else
                {
                    Write-Verbose "[$(Get-Date -Format G)] - $computer - OMS Agent not installed so skipping."
                }
            }
            catch
            {
                Write-Error $_
            }
            Finally
            {
                Write-Verbose "[$(Get-Date -Format G)] - $computer - Tidying up install files\sessions if needed"

                if($null -ne $psSession)
                {
                    try
                    {
                        Invoke-Command -Session $pssession -ScriptBlock {
                            if(Test-Path $USING:path)
                            {
                                Remove-Item $USING:path -force -Confirm:$false
                            }
                        } -ErrorAction Stop
                    }
                    catch
                    {
                        Write-Verbose "[$(Get-Date -Format G)] - $computer - Nothing to tidy up"
                    }

                    Remove-PSSession $psSession -whatif:$false -Confirm:$false
                }
            }
        }
    }
}