SharedResources/Src/ConfigSQLServer/xSQLServer/DSCResources/MSFT_xSQLAOGroupEnsure/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
    }
    
    $vConfigured = Test-TargetResource -Ensure $Ensure -AvailabilityGroupName $AvailabilityGroupName -SQLServer $SQLServer -SQLInstanceName $SQLInstanceName 

    $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]
        $AutoBackupPrefernce ="Primary",

        [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="Primary"
                $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):5022"
                    $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 = 50
                    $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):5022"
                    $asyncReplica.FailoverMode = [Microsoft.SqlServer.Management.Smo.AvailabilityReplicaFailoverMode]::Manual
                    $asyncReplica.AvailabilityMode = [Microsoft.SqlServer.Management.Smo.AvailabilityReplicaAvailabilityMode]::ASynchronousCommit
                    $asyncReplica.BackupPriority = 50
                    $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..."
                Exit
             }    

           #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()
                 NNew-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]
        $AutoBackupPrefernce="Primary",

        [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
    }

    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