functions/Export-DbaLogin.ps1

function Export-DbaLogin {
    <#
        .SYNOPSIS
            Exports Windows and SQL Logins to a T-SQL file. Export includes login, SID, password, default database, default language, server permissions, server roles, db permissions, db roles.
 
        .DESCRIPTION
            Exports Windows and SQL Logins to a T-SQL file. Export includes login, SID, password, default database, default language, server permissions, server roles, db permissions, db roles.
 
        .PARAMETER SqlInstance
            The SQL Server instance name. SQL Server 2000 and above supported.
 
        .PARAMETER SqlCredential
            Login to the target instance using alternative credentials. Windows and SQL Authentication supported. Accepts credential objects (Get-Credential)
 
        .PARAMETER Login
            The login(s) to process. Options for this list are auto-populated from the server. If unspecified, all logins will be processed.
 
        .PARAMETER ExcludeLogin
            The login(s) to exclude. Options for this list are auto-populated from the server.
 
        .PARAMETER Database
            The database(s) to process. Options for this list are auto-populated from the server. If unspecified, all databases will be processed.
 
        .PARAMETER FilePath
            The file to write to.
 
        .PARAMETER NoClobber
            If this switch is enabled, a file already existing at the path specified by FilePath will not be overwritten.
 
        .PARAMETER Append
            If this switch is enabled, content will be appended to a file already existing at the path specified by FilePath. If the file does not exist, it will be created.
 
        .PARAMETER NoJobs
            If this switch is enabled, Agent job ownership will not be exported.
 
        .PARAMETER NoDatabases
            If this switch is enabled, mappings for databases will not be exported.
 
        .PARAMETER WhatIf
            If this switch is enabled, no actions are performed but informational messages will be displayed that explain what would happen if the command were to run.
 
        .PARAMETER Confirm
            If this switch is enabled, you will be prompted for confirmation before executing any operations that change state.
 
        .PARAMETER EnableException
            By default, when something goes wrong we try to catch it, interpret it and give you a friendly warning message.
            This avoids overwhelming you with "sea of red" exceptions, but is inconvenient because it basically disables advanced scripting.
            Using this switch turns this "nice by default" feature off and enables you to catch exceptions with your own try/catch.
 
        .PARAMETER ExcludeGoBatchSeparator
            If specified, will NOT script the 'GO' batch separator.
 
        .PARAMETER DestinationVersion
            To say to which version the script should be generated. If not specified will use instance major version.
 
        .NOTES
            Tags: Export, Login
            Author: Chrissy LeMaire (@cl), netnerds.net
            Website: https://dbatools.io
            Copyright: (C) Chrissy LeMaire, clemaire@gmail.com
            License: MIT https://opensource.org/licenses/MIT
 
        .LINK
            https://dbatools.io/Export-DbaLogin
 
        .EXAMPLE
            Export-DbaLogin -SqlInstance sql2005 -FilePath C:\temp\sql2005-logins.sql
 
            Exports the logins for SQL Server "sql2005" and writes them to the file "C:\temp\sql2005-logins.sql"
 
        .EXAMPLE
            Export-DbaLogin -SqlInstance sqlserver2014a -Exclude realcajun -SqlCredential $scred -FilePath C:\temp\logins.sql -Append
 
            Authenticates to sqlserver2014a using SQL Authentication. Exports all logins except for realcajun to C:\temp\logins.sql, and appends to the file if it exists. If not, the file will be created.
 
        .EXAMPLE
            Export-DbaLogin -SqlInstance sqlserver2014a -Login realcajun, netnerds -FilePath C:\temp\logins.sql
 
            Exports ONLY logins netnerds and realcajun FROM sqlserver2014a to the file C:\temp\logins.sql
 
        .EXAMPLE
            Export-DbaLogin -SqlInstance sqlserver2014a -Login realcajun, netnerds -Database HR, Accounting
 
            Exports ONLY logins netnerds and realcajun FROM sqlserver2014a with the permissions on databases HR and Accounting
 
        .EXAMPLE
            Export-DbaLogin -SqlInstance sqlserver2008 -Login realcajun, netnerds -FilePath C:\temp\login.sql -ExcludeGoBatchSeparator
 
            Exports ONLY logins netnerds and realcajun FROM sqlserver2008 server, to the C:\temp\login.sql file without the 'GO' batch separator.
 
        .EXAMPLE
            Export-DbaLogin -SqlInstance sqlserver2008 -Login realcajun -FilePath C:\temp\users.sql -DestinationVersion SQLServer2016
 
            Exports login realcajun fron sqlsever2008 to the file C:\temp\users.sql with sintax to run on SQL Server 2016
    #>

    [CmdletBinding(SupportsShouldProcess = $true)]
    param (
        [parameter(Mandatory = $true, ValueFromPipeline = $true)]
        [Alias("ServerInstance", "SqlServer")]
        [DbaInstanceParameter]$SqlInstance,
        [Alias("Credential")]
        [PSCredential]
        $SqlCredential,
        [object[]]$Login,
        [object[]]$ExcludeLogin,
        [Alias("Databases")]
        [object[]]$Database,
        [Alias("OutFile", "Path", "FileName")]
        [string]$FilePath,
        [Alias("NoOverwrite")]
        [switch]$NoClobber,
        [switch]$Append,
        [switch]$NoDatabases,
        [switch]$NoJobs,
        [Alias('Silent')]
        [switch]$EnableException,
        [switch]$ExcludeGoBatchSeparator,
        [ValidateSet('SQLServer2000', 'SQLServer2005', 'SQLServer2008/2008R2', 'SQLServer2012', 'SQLServer2014', 'SQLServer2016', 'SQLServer2017')]
        [string]$DestinationVersion
    )

    begin {

        if ($FilePath) {
            if ($FilePath -notlike "*\*") {
                $FilePath = ".\$filepath"
            }
            $directory = Split-Path $FilePath
            $exists = Test-Path $directory

            if ($exists -eq $false) {
                Write-Message -Level Warning -Message "Parent directory $directory does not exist."
            }
        }

        $outsql = @()

        $versions = @{
            'SQLServer2000'        = 'Version80'
            'SQLServer2005'        = 'Version90'
            'SQLServer2008/2008R2' = 'Version100'
            'SQLServer2012'        = 'Version110'
            'SQLServer2014'        = 'Version120'
            'SQLServer2016'        = 'Version130'
            'SQLServer2017'        = 'Version140'
        }

        $versionsNumbers = @{
            '8'  = 'Version80'
            '9'  = 'Version90'
            '10' = 'Version100'
            '11' = 'Version110'
            '12' = 'Version120'
            '13' = 'Version130'
            '14' = 'Version140'
        }
    }
    process {
        if (Test-FunctionInterrupt) {
            return
        }

        Write-Message -Level Verbose -Message "Connecting to $sqlinstance."
        $server = Connect-SqlInstance -SqlInstance $SqlInstance -SqlCredential $sqlcredential

        if ([string]::IsNullOrEmpty($destinationVersion)) {
            #Get compatibility level for scripting the objects
            $scriptVersion = $versionsNumbers[$server.VersionMajor.ToString()]
        }
        else {
            $scriptVersion = $versions[$destinationVersion]
        }

        if ($NoDatabases -eq $false -or $Database) {
            # if we got a database or a list of databases passed
            # and we need to enumerate mappings, login.enumdatabasemappings() takes forever
            # the cool thing though is that database.enumloginmappings() is fast. A lot.
            # if we get a list of databases passed (or even the default list of all the databases)
            # we save outself a call to enumloginmappings if there is no map at all
            $DbMapping = @()
            $DbsToMap = $server.Databases
            if ($Database) {
                $DbsToMap = $DbsToMap | Where-Object Name -in $Database
            }
            foreach ($db in $DbsToMap) {
                if ($db.IsAccessible -eq $false) {
                    continue
                }
                $dbmap = $db.EnumLoginMappings()
                foreach ($el in $dbmap) {
                    $DbMapping += [pscustomobject]@{
                        Database  = $db.Name
                        UserName  = $el.Username
                        LoginName = $el.LoginName
                    }
                }
            }
        }

        foreach ($sourceLogin in $server.Logins) {
            $userName = $sourceLogin.name

            if ($Login -and $Login -notcontains $userName -or $ExcludeLogin -contains $userName) {
                continue
            }

            if ($userName.StartsWith("##") -or $userName -eq 'sa') {
                Write-Message -Level Warning -Message "Skipping $userName."
                continue
            }

            $serverName = $server

            $userBase = ($userName.Split("\")[0]).ToLower()
            if ($serverName -eq $userBase -or $userName.StartsWith("NT ")) {
                if ($Pscmdlet.ShouldProcess("console", "Stating $userName is skipped because it is a local machine name.")) {
                    Write-Message -Level Warning -Message "$userName is skipped because it is a local machine name."
                    continue
                }
            }

            if ($Pscmdlet.ShouldProcess("Outfile", "Adding T-SQL for login $userName")) {
                if ($FilePath) {
                    Write-Message -Level Output -Message "Exporting $userName."
                }

                $outsql += "`r`nUSE master`n"
                # Getting some attributes
                $defaultDb = $sourceLogin.DefaultDatabase
                $language = $sourceLogin.Language

                if ($sourceLogin.PasswordPolicyEnforced -eq $false) {
                    $checkPolicy = "OFF"
                }
                else {
                    $checkPolicy = "ON"
                }

                if (!$sourceLogin.PasswordExpirationEnabled) {
                    $checkExpiration = "OFF"
                }
                else {
                    $checkExpiration = "ON"
                }

                # Attempt to script out SQL Login
                if ($sourceLogin.LoginType -eq "SqlLogin") {
                    $sourceLoginName = $sourceLogin.name

                    switch ($server.versionMajor) {
                        0 {
                            $sql = "SELECT CONVERT(VARBINARY(256),password) AS hashedpass FROM master.dbo.syslogins WHERE loginname='$sourceLoginName'"
                        }
                        8 {
                            $sql = "SELECT CONVERT(VARBINARY(256),password) AS hashedpass FROM dbo.syslogins WHERE name='$sourceLoginName'"
                        }
                        9 {
                            $sql = "SELECT CONVERT(VARBINARY(256),password_hash) as hashedpass FROM sys.sql_logins WHERE name='$sourceLoginName'"
                        }
                        default {
                            $sql = "SELECT CAST(CONVERT(varchar(256), CAST(LOGINPROPERTY(name,'PasswordHash') AS VARBINARY(256)), 1) AS NVARCHAR(max)) AS hashedpass FROM sys.server_principals WHERE principal_id = $($sourceLogin.id)"
                        }
                    }

                    try {
                        $hashedPass = $server.ConnectionContext.ExecuteScalar($sql)
                    }
                    catch {
                        $hashedPassDt = $server.Databases['master'].ExecuteWithResults($sql)
                        $hashedPass = $hashedPassDt.Tables[0].Rows[0].Item(0)
                    }

                    if ($hashedPass.GetType().Name -ne "String") {
                        $passString = "0x"; $hashedPass | ForEach-Object {
                            $passString += ("{0:X}" -f $_).PadLeft(2, "0")
                        }
                        $hashedPass = $passString
                    }

                    $sid = "0x"; $sourceLogin.sid | ForEach-Object {
                        $sid += ("{0:X}" -f $_).PadLeft(2, "0")
                    }
                    $outsql += "IF NOT EXISTS (SELECT loginname FROM master.dbo.syslogins WHERE name = '$userName') CREATE LOGIN [$userName] WITH PASSWORD = $hashedPass HASHED, SID = $sid, DEFAULT_DATABASE = [$defaultDb], CHECK_POLICY = $checkPolicy, CHECK_EXPIRATION = $checkExpiration, DEFAULT_LANGUAGE = [$language]"
                }
                # Attempt to script out Windows User
                elseif ($sourceLogin.LoginType -eq "WindowsUser" -or $sourceLogin.LoginType -eq "WindowsGroup") {
                    $outsql += "IF NOT EXISTS (SELECT loginname FROM master.dbo.syslogins WHERE name = '$userName') CREATE LOGIN [$userName] FROM WINDOWS WITH DEFAULT_DATABASE = [$defaultDb], DEFAULT_LANGUAGE = [$language]"
                }
                # This script does not currently support certificate mapped or asymmetric key users.
                else {
                    Write-Message -Level Warning -Message "$($sourceLogin.LoginType) logins not supported. $($sourceLogin.Name) skipped."
                    continue
                }

                if ($sourceLogin.IsDisabled) {
                    $outsql += "ALTER LOGIN [$userName] DISABLE"
                }

                if ($sourceLogin.DenyWindowsLogin) {
                    $outsql += "DENY CONNECT SQL TO [$userName]"
                }
            }

            # Server Roles: sysadmin, bulklogin, etc
            foreach ($role in $server.Roles) {
                $roleName = $role.Name

                # SMO changed over time
                try {
                    $roleMembers = $role.EnumMemberNames()
                }
                catch {
                    $roleMembers = $role.EnumServerRoleMembers()
                }

                if ($roleMembers -contains $userName) {
                    if (($server.VersionMajor -lt 11 -and [string]::IsNullOrEmpty($destinationVersion)) -or ($DestinationVersion -in "SQLServer2000", "SQLServer2005", "SQLServer2008/2008R2")) {
                        $outsql += "EXEC sys.sp_addsrvrolemember @rolename=N'$roleName', @loginame=N'$userName'"
                    }
                    else {
                        $outsql += "ALTER SERVER ROLE [$roleName] ADD MEMBER [$userName]"
                    }
                }
            }

            if ($NoJobs -eq $false) {
                $ownedJobs = $server.JobServer.Jobs | Where-Object { $_.OwnerLoginName -eq $userName }

                foreach ($ownedJob in $ownedJobs) {
                    $outsql += "`n`rUSE msdb`n"
                    $outsql += "EXEC msdb.dbo.sp_update_job @job_name=N'$ownedJob', @owner_login_name=N'$userName'"
                }
            }

            if ($server.VersionMajor -ge 9) {
                # These operations are only supported by SQL Server 2005 and above.
                # Securables: Connect SQL, View any database, Administer Bulk Operations, etc.

                $perms = $server.EnumServerPermissions($userName)
                $outsql += "`n`rUSE master`n"
                foreach ($perm in $perms) {
                    $permState = $perm.permissionstate
                    $permType = $perm.PermissionType
                    $grantor = $perm.grantor

                    if ($permState -eq "GrantWithGrant") {
                        $grantWithGrant = "WITH GRANT OPTION"
                        $permState = "GRANT"
                    }
                    else {
                        $grantWithGrant = $null
                    }

                    $outsql += "$permState $permType TO [$userName] $grantWithGrant AS [$grantor]"
                }

                # Credential mapping. Credential removal not currently supported for Syncs.
                $loginCredentials = $server.Credentials | Where-Object { $_.Identity -eq $sourceLogin.Name }
                foreach ($credential in $loginCredentials) {
                    $credentialName = $credential.Name
                    $outsql += "PRINT '$userName is associated with the $credentialName credential'"
                }
            }

            if ($NoDatabases -eq $false) {
                $dbs = $sourceLogin.EnumDatabaseMappings()

                if ($Database) {
                    $dbs = $dbs | Where-Object { $_.DBName -in $Database }
                }

                # Adding database mappings and securables
                foreach ($db in $dbs) {
                    $dbName = $db.dbname
                    $sourceDb = $server.Databases[$dbName]
                    $dbUserName = $db.username

                    $outsql += "`r`nUSE [$dbName]`n"
                    try {
                        $sql = $server.Databases[$dbName].Users[$dbUserName].Script()
                        $outsql += $sql
                    }
                    catch {
                        Write-Message -Level Warning -Message "User cannot be found in selected database."
                    }

                    # Skipping updating dbowner

                    # Database Roles: db_owner, db_datareader, etc
                    foreach ($role in $sourceDb.Roles) {
                        if ($role.EnumMembers() -contains $dbUserName) {
                            $roleName = $role.Name
                            if (($server.VersionMajor -lt 11 -and [string]::IsNullOrEmpty($destinationVersion)) -or ($DestinationVersion -in "SQLServer2000", "SQLServer2005", "SQLServer2008/2008R2")) {
                                $outsql += "EXEC sys.sp_addrolemember @rolename=N'$roleName', @membername=N'$dbUserName'"
                            }
                            else {
                                $outsql += "ALTER ROLE [$roleName] ADD MEMBER [$dbUserName]"
                            }
                        }
                    }

                    # Connect, Alter Any Assembly, etc
                    $perms = $sourceDb.EnumDatabasePermissions($dbUserName)
                    foreach ($perm in $perms) {
                        $permState = $perm.PermissionState
                        $permType = $perm.PermissionType
                        $grantor = $perm.Grantor

                        if ($permState -eq "GrantWithGrant") {
                            $grantWithGrant = "WITH GRANT OPTION"
                            $permState = "GRANT"
                        }
                        else {
                            $grantWithGrant = $null
                        }

                        $outsql += "$permState $permType TO [$userName] $grantWithGrant AS [$grantor]"
                    }
                }
            }
        }
    }
    end {
        $sql = $sql | Where-Object { $_ -notlike "CREATE USER [dbo] FOR LOGIN * WITH DEFAULT_SCHEMA=[dbo]" }

        if ($ExcludeGoBatchSeparator) {
            $sql = $outsql
        }
        else {
            $sql = $outsql -join "`r`nGO`r`n"
            #add the final GO
            $sql += "`r`nGO"
        }

        if ($FilePath) {
            $sql | Out-File -Encoding UTF8 -FilePath $FilePath -Append:$Append -NoClobber:$NoClobber
        }
        else {
            $sql
        }
        Test-DbaDeprecation -DeprecatedOn "1.0.0" -EnableException:$false -Alias Export-SqlLogin
    }
}