MSFT_xSQLAOGroupEnsure.psm1

$currentPath = Split-Path -Parent $MyInvocation.MyCommand.Path
Write-Verbose -Message "CurrentPath: $currentPath"

# Load Common Code
Import-Module $currentPath\..\..\xSQLServerHelper.psm1 -Verbose:$false -ErrorAction Stop

function Get-TargetResource
{
    [CmdletBinding()]
    [OutputType([System.Collections.Hashtable])]
    param
    (
        [parameter(Mandatory = $true)]
        [ValidateSet("Present","Absent")]
        [System.String]
        $Ensure,

        [parameter(Mandatory = $true)]
        [System.String]
        $AvailabilityGroupName,
        
        [System.String]
        $SQLServer = $env:COMPUTERNAME,

        [ValidateNotNull()] 
        [System.String]
        $SQLInstanceName= "MSSQLSERVER",

        [parameter(Mandatory = $true)]
        [System.Management.Automation.PSCredential]
        $SetupCredential
    )

    if(!$SQL)
    {
        $SQL = Connect-SQL -SQLServer $SQLServer -SQLInstanceName $SQLInstanceName -SetupCredential $SetupCredential
    }
    
    $vConfigured = Test-TargetResource -Ensure $Ensure -AvailabilityGroupName $AvailabilityGroupName -SQLServer $SQLServer -SQLInstanceName $SQLInstanceName -SetupCredential $SetupCredential

    $returnValue = @{
    Ensure = $vConfigured
    AvailabilityGroupName = $sql.AvailabilityGroups[$AvailabilityGroupName]
    AvailabilityGroupNameListener = $sql.AvailabilityGroups[$AvailabilityGroupName].AvailabilityGroupListeners.name
    AvailabilityGroupNameIP = $sql.AvailabilityGroups[$AvailabilityGroupName].AvailabilityGroupListeners.availabilitygrouplisteneripaddresses.IPAddress
    AvailabilityGroupSubMask =  $sql.AvailabilityGroups[$AvailabilityGroupName].AvailabilityGroupListeners.availabilitygrouplisteneripaddresses.SubnetMask
    AvailabilityGroupPort =  $sql.AvailabilityGroups[$AvailabilityGroupName].AvailabilityGroupListeners.portnumber
    AvailabilityGroupNameDatabase = $sql.AvailabilityGroups[$AvailabilityGroupName].AvailabilityDatabases.name
    BackupDirectory = ""
    SQLServer = $SQLServer
    SQLInstanceName = $SQLInstanceName
    }

    $returnValue
}


function Set-TargetResource
{
    [CmdletBinding()]
    param
    (
        [parameter(Mandatory = $true)]
        [ValidateSet("Present", "Absent")]
        [System.String]
        $Ensure,

        [parameter(Mandatory = $true)]
        [System.String]
        $AvailabilityGroupName,

        [System.String]
        $AvailabilityGroupNameListener = $AvailabilityGroupName,

        [System.String[]]
        $AvailabilityGroupNameIP,

        [System.String[]]
        $AvailabilityGroupSubMask,

        [System.UInt32]
        $AvailabilityGroupPort = "1433",

        [ValidateSet("None", "ReadOnly", "ReadIntent")]
        [System.String]
        $ReadableSecondary = "ReadOnly",

        [ValidateSet("Primary", "Secondary")]
        [System.String]
        $AutoBackupPreference = "Primary",
        
        [System.UInt32]
        $BackupPriority = "50",
        
        [System.UInt32]
        $EndPointPort = "5022",

        [System.String]
        $SQLServer = $env:COMPUTERNAME,

        [System.String]
        $SQLInstanceName = "MSSQLSERVER",
        
        [parameter(Mandatory = $true)]
        [System.Management.Automation.PSCredential]
        $SetupCredential
    )

    $null = [System.Reflection.Assembly]::LoadWithPartialName('Microsoft.SqlServer.Smo')
    $null = [System.Reflection.Assembly]::LoadWithPartialName("Microsoft.SqlServer.SmoExtended")
   
    if(!$SQL)
    {
        $SQL = Connect-SQL -SQLServer $SQLServer -SQLInstanceName $SQLInstanceName -SetupCredential $SetupCredential
    }

    if (($AvailabilityGroupNameIP -and !$AvailabilityGroupSubMask) -or (!$AvailabilityGroupNameIP -and $AvailabilityGroupSubMask))
    {
        Throw "AvailabilityGroupNameIP and AvailabilityGroupSubMask must both be passed for Static IP assignment."
        Exit
    }

    Switch ($Ensure)
    {
        "Present"
        {
            Grant-ServerPerms -SQLServer $SQLServer -SQLInstanceName $SQLInstanceName -AuthorizedUser "NT AUTHORITY\SYSTEM" -SetupCredential $SetupCredential
            New-ListenerADObject -AvailabilityGroupNameListener $AvailabilityGroupNameListener -SetupCredential $SetupCredential
           
            $FailoverCondition = 3
            $HealthCheckTimeout = 30000
            $ConnectionModeInPrimary = "AllowAllConnections"    
            $ConnectionModeInSecondaryRole = switch ($ReadableSecondary)
                               {
                                   'None' {"AllowNoConnections"}
                                   'ReadOnly' {"AllowAllConnections"}
                                   'ReadIntent' {"AllowReadIntentConnectionsOnly"}
                                   Default {"AllowAllConnections"}
                               } 

           #Get Servers participating in the cluster
           #First two nodes will account for Syncronous Automatic Failover, Any additional will be Asyncronous
           try
           {
                $nodes = Get-ClusterNode -cluster $sql.ClusterName -Verbose:$false |  select -ExpandProperty name
                $syncNodes = $nodes | Select-Object -First 2
                $asyncNodes = $nodes | Select-Object -Skip 2
                $availabilityGroup = New-Object -typename Microsoft.SqlServer.Management.Smo.AvailabilityGroup -ArgumentList $SQL, $AvailabilityGroupName
                $availabilityGroup.AutomatedBackupPreference = $AutoBackupPreference
                $availabilityGroup.FailureConditionLevel = $FailoverCondition
                $availabilityGroup.HealthCheckTimeout = $HealthCheckTimeout
           }
           Catch
           {
                Throw "Failed to connect to Cluster Nodes from $($sql.ClusterName)"
                Exit
           }

           #Loop through Sync nodes Create Replica Object Assign properties and add it to AvailabilityGroup
           foreach ($node in $syncNodes)
           { 
                Try
                {
                    $Replica = New-Object -typename Microsoft.SqlServer.Management.Smo.AvailabilityReplica -ArgumentList $availabilityGroup, $node
                    $Replica.EndpointUrl = "TCP://$($node):$EndPointPort"
                    $Replica.FailoverMode = [Microsoft.SqlServer.Management.Smo.AvailabilityReplicaFailoverMode]::Automatic
                    $Replica.AvailabilityMode = [Microsoft.SqlServer.Management.Smo.AvailabilityReplicaAvailabilityMode]::SynchronousCommit
                    #Backup Priority Gives the ability to set a priority of one secondany over another valid values are from 1 - 100
                    $Replica.BackupPriority = $BackupPriority
                    $Replica.ConnectionModeInPrimaryRole =  $ConnectionModeInPrimary
                    $replica.ConnectionModeInSecondaryRole = $ConnectionModeInSecondaryRole 
                    $availabilityGroup.AvailabilityReplicas.Add($Replica)
                }
                Catch
                {
                    Throw "Failed to add $Replica to the Availability Group $AvailabilityGroupName"
                    Exit
                }         
            }

            #Loop through ASync nodes Create Replica Object Assign properties and add it to AvailabilityGroup
            foreach ($node in $AsyncNodes)
            {
                Try
                {
                    $asyncReplica = New-Object -typename Microsoft.SqlServer.Management.Smo.AvailabilityReplica -ArgumentList $availabilityGroup, $node
                    $asyncReplica.EndpointUrl = "TCP://$($node):$EndPointPort"
                    $asyncReplica.FailoverMode = [Microsoft.SqlServer.Management.Smo.AvailabilityReplicaFailoverMode]::Manual
                    $asyncReplica.AvailabilityMode = [Microsoft.SqlServer.Management.Smo.AvailabilityReplicaAvailabilityMode]::ASynchronousCommit
                    $asyncReplica.BackupPriority = $BackupPriority
                    $asyncReplica.ConnectionModeInPrimaryRole =  $ConnectionModeInPrimary
                    $asyncReplica.ConnectionModeInSecondaryRole = $ConnectionModeInSecondaryRole 
                    $AvailabilityGroup.AvailabilityReplicas.Add($asyncReplica)
                }
                Catch
                {
                    Write-Error "Failed to add $asyncReplica to the Availability Group $AvailabilityGroupName"
                }
            }
        
            Try{
                $AgListener = New-Object -typename Microsoft.SqlServer.Management.Smo.AvailabilityGroupListener -ArgumentList $AvailabilityGroup, $AvailabilityGroupNameListener
                $AgListener.PortNumber =$AvailabilityGroupPort
            }
            Catch{
                Write-Error -Message ((Get-Date -format yyyy-MM-dd_HH-mm-ss) + ": Failed to Create AG Listener Object");
            }
         
         
            If($AvailabilityGroupNameIP)
            {
                Foreach ($IP in $AvailabilityGroupNameIP)
                {
                    $AgListenerIp = New-Object -typename Microsoft.SqlServer.Management.Smo.AvailabilityGroupListenerIPAddress -ArgumentList $AgListener
                    $AgListenerIp.IsDHCP = $false
                    $AgListenerIp.IPAddress = $IP
                    $AgListenerIp.SubnetMask = $AvailabilityGroupSubMask
                    $AgListener.AvailabilityGroupListenerIPAddresses.Add($AgListenerIp)
                    New-VerboseMessage -Message "Added Static IP $IP to $AvailabilityGroupNameListener..."
            
                }
            }
            Else
            {
                #Utilize Dynamic IP since no Ip was passed
                $AgListenerIp = New-Object -typename Microsoft.SqlServer.Management.Smo.AvailabilityGroupListenerIPAddress -ArgumentList $AgListener
                $AgListenerIp.IsDHCP = $true
                $AgListener.AvailabilityGroupListenerIPAddresses.Add($AgListenerIp)
                New-VerboseMessage -Message "Added DynamicIP to $AvailabilityGroupNameListener..."
            }
         
            Try{
                $AvailabilityGroup.AvailabilityGroupListeners.Add($AgListener);
            }
            Catch{
                Throw "Failed to Add $AvailabilityGroupNameListener to $AvailabilityGroupName..."
            }    

            #Add Availabilty Group to the SQL connection
            Try{
                $SQL.AvailabilityGroups.Add($availabilityGroup)
                New-VerboseMessage -Message "Added $availabilityGroupName Availability Group to Connection"  
            }
            Catch{
                    Throw "Unable to Add $AvailabilityGroup to $SQLServer\$SQLInstanceName"
                    Exit
            }
           
            #Create Availability Group
            Try{
                $availabilityGroup.Create()
                New-VerboseMessage -Message "Created Availability Group $availabilityGroupName"
            }
            Catch{
                Throw "Unable to Create $AvailabilityGroup on $SQLServer\$SQLInstanceName"
                Exit
            }
           
        }
        "Absent"
        { 
            Try{
                 $sql.AvailabilityGroups[$AvailabilityGroupName].Drop()
                 New-VerboseMessage -Message "Dropped $AvailabilityGroupName" 
            }
            Catch{
                 Throw "Unable to Drop $AvailabilityGroup on $SQLServer\$SQLInstanceName"
            }
        }
    }



}

function Test-TargetResource
{
    [CmdletBinding()]
    [OutputType([System.Boolean])]
    param
    (
        [parameter(Mandatory = $true)]
        [ValidateSet("Present", "Absent")]
        [System.String]
        $Ensure,

        [parameter(Mandatory = $true)]
        [System.String]
        $AvailabilityGroupName,

        [System.String]
        $AvailabilityGroupNameListener,

        [System.String[]]
        $AvailabilityGroupNameIP,

        [System.String[]]
        $AvailabilityGroupSubMask,

        [System.UInt32]
        $AvailabilityGroupPort,

        [ValidateSet("None", "ReadOnly", "ReadIntent")]
        [System.String]
        $ReadableSecondary ="ReadOnly",

        [ValidateSet("Primary", "Secondary")]
        [System.String]
        $AutoBackupPreference = "Primary",
        
        [System.UInt32]
        $BackupPriority = "50",
        
        [System.UInt32]
        $EndPointPort = "5022",

        [System.String]
        $SQLServer = $env:COMPUTERNAME,

        [System.String]
        $SQLInstanceName = "MSSQLSERVER",
        
        [parameter(Mandatory = $true)]
        [System.Management.Automation.PSCredential]
        $SetupCredential
    )

    if(!$SQL)
    {
        $SQL = Connect-SQL -SQLServer $SQLServer -SQLInstanceName $SQLInstanceName -SetupCredential $SetupCredential
    }

    Switch ($Ensure)
    {
        "Present"
        {
            $AGPresent=$sql.AvailabilityGroups.Contains($AvailabilityGroupName)
            if ($AGPresent)
                {$Return = $true}
            else
                {$Return = $false}
        }
        "Absent"
        {
            if(!$sql.AvailabilityGroups[$AvailabilityGroupName])
            {$Return = $true}
            else{$Return = $false}
        }
    }
    $Return

}


Export-ModuleMember -Function *-TargetResource