functions/Export-DbaUser.ps1

function Export-DbaUser {
    <#
        .SYNOPSIS
            Exports users creation and its permissions to a T-SQL file or host.
 
        .DESCRIPTION
            Exports users creation and its permissions to a T-SQL file or host. Export includes user, create and add to role(s), database level permissions, object level permissions.
 
        .PARAMETER SqlInstance
            The SQL Server instance name. SQL Server 2000 and above supported.
 
        .PARAMETER SqlCredential
            Allows you to login to servers using alternative credentials
 
            $scred = Get-Credential, then pass $scred object to the -SqlCredential parameter
 
            Windows Authentication will be used if SqlCredential is not specified
 
        .PARAMETER Database
            The database(s) to process - this list is auto-populated from the server. If unspecified, all databases will be processed.
 
        .PARAMETER ExcludeDatabase
            The database(s) to exclude - this list is auto-populated from the server
 
        .PARAMETER User
            Export only the specified database user(s). If not specified will export all users from the database(s)
 
        .PARAMETER DestinationVersion
            To say to which version the script should be generated. If not specified will use database compatibility level
 
        .PARAMETER FilePath
            The file to write to.
 
        .PARAMETER NoClobber
            Do not overwrite file
 
        .PARAMETER Append
            Append to file
 
        .PARAMETER WhatIf
            Shows what would happen if the command were to run. No actions are actually performed.
 
        .PARAMETER Confirm
            Prompts you for confirmation before executing any changing operations within the command.
 
        .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.
             
        .NOTES
            Tags: User, Export
            Author: Claudio Silva (@ClaudioESSilva)
 
            Website: https://dbatools.io
            Copyright: (C) Chrissy LeMaire, clemaire@gmail.com
            License: GNU GPL v3 https://opensource.org/licenses/GPL-3.0
 
        .LINK
            https://dbatools.io/Export-DbaUser
 
        .EXAMPLE
            Export-DbaUser -SqlInstance sql2005 -FilePath C:\temp\sql2005-users.sql
 
            Exports SQL for the users in server "sql2005" and writes them to the file "C:\temp\sql2005-users.sql"
 
        .EXAMPLE
            Export-DbaUser -SqlInstance sqlserver2014a $scred -FilePath C:\temp\users.sql -Append
 
            Authenticates to sqlserver2014a using SQL Authentication. Exports all users to C:\temp\users.sql, and appends to the file if it exists. If not, the file will be created.
 
        .EXAMPLE
            Export-DbaUser -SqlInstance sqlserver2014a -User User1, User2 -FilePath C:\temp\users.sql
 
            Exports ONLY users User1 and User2 fron sqlsever2014a to the file C:\temp\users.sql
 
        .EXAMPLE
            Export-DbaUser -SqlInstance sqlserver2008 -User User1 -FilePath C:\temp\users.sql -DestinationVersion SQLServer2016
 
            Exports user User1 fron sqlsever2008 to the file C:\temp\users.sql with sintax to run on SQL Server 2016
 
        .EXAMPLE
            Export-DbaUser -SqlInstance sqlserver2008 -Database db1,db2 -FilePath C:\temp\users.sql
 
            Expors ONLY users from db1 and db2 database on sqlserver2008 server, to the C:\temp\users.sql file.
    #>

    [CmdletBinding(DefaultParameterSetName = "Default")]
    [OutputType([String])]
    param (
        [parameter(Mandatory = $true, ValueFromPipeline = $true)]
        [Alias("ServerInstance", "SqlServer")]
        [DbaInstanceParameter]$SqlInstance,
        [Alias("Credential")]
        [PSCredential]
        $SqlCredential,
        [Alias("Databases")]
        [object[]]$Database,
        [object[]]$ExcludeDatabase,
        [object[]]$User,
        [ValidateSet('SQLServer2000', 'SQLServer2005', 'SQLServer2008/2008R2', 'SQLServer2012', 'SQLServer2014', 'SQLServer2016')]
        [string]$DestinationVersion,
        [Alias("OutFile", "Path", "FileName")]
        [string]$FilePath,
        [Alias("NoOverwrite")]
        [switch]$NoClobber,
        [switch]$Append,
        [switch][Alias('Silent')]$EnableException
    )

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

            if ($exists -eq $false) {
                Stop-Function -Message "Parent directory $directory does not exist"
                return
            }

            Write-Message -Level Output -Message "Attempting to connect to SQL Servers.."
        }

        $outsql = @()

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

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

    }
    process {
        if (Test-FunctionInterrupt) { return }

        try {
            Write-Message -Level Verbose -Message "Connecting to $sqlinstance"
            $server = Connect-SqlInstance -SqlInstance $SqlInstance -SqlCredential $sqlcredential
        }
        catch {
            Stop-Function -Message "Failure" -Category ConnectionError -ErrorRecord $_ -Target $instance -Continue
        }

        if (!$database) {
            $databases = $server.Databases | Where-Object { $ExcludeDatabase -notcontains $_.Name -and $_.IsAccessible -eq $true }
        }
        else {
            if ($pipedatabase) {
                $source = $pipedatabase[0].parent.name
                $databases = $pipedatabase.name
            }
            else {
                $databases = $server.Databases | Where-Object { $_.IsAccessible -eq $true -and ($database -contains $_.Name) }
            }
        }

        if ($exclude) {
            $databases = $databases | Where-Object Name -notin $ExcludeDatabase
        }

        if (@($databases).Count -gt 0) {

            #Database Permissions
            foreach ($db in $databases) {
                if ([string]::IsNullOrEmpty($destinationVersion)) {
                    #Get compatibility level for scripting the objects
                    $scriptVersion = $db.CompatibilityLevel
                }
                else {
                    $scriptVersion = $versions[$destinationVersion]
                }
                $versionNameDesc = $versionName[$scriptVersion.ToString()]

                #Options
                $scriptingOptions = New-DbaScriptingOption
                $scriptingOptions.TargetServerVersion = [Microsoft.SqlServer.Management.Smo.SqlServerVersion]::$scriptVersion
                $scriptingOptions.AllowSystemObjects = $false
                $scriptingOptions.IncludeDatabaseRoleMemberships = $true
                $scriptingOptions.ContinueScriptingOnError = $false
                $scriptingOptions.IncludeDatabaseContext = $false

                Write-Message -Level Output -Message "Validating users on database $db"

                if ($User.Count -eq 0) {
                    $users = $db.Users | Where-Object { $_.IsSystemObject -eq $false -and $_.Name -notlike "##*" }
                }
                else {
                    if ($pipedatabase) {
                        $source = $pipedatabase[3].parent.name
                        $users = $pipedatabase.name
                    }
                    else {
                        $users = $db.Users | Where-Object { $User -contains $_.Name -and $_.IsSystemObject -eq $false -and $_.Name -notlike "##*" }
                    }
                }
                # Store roles between users so if we hit the same one we dont create it again
                $roles = @()
                if ($users.Count -gt 0) {
                    foreach ($dbuser in $users) {
                        #setting database
                        $outsql += "USE [" + $db.Name + "]"

                        try {
                            #Fixed Roles #Dependency Issue. Create Role, before add to role.
                            foreach ($rolePermission in ($db.Roles | Where-Object { $_.IsFixedRole -eq $false })) {
                                foreach ($rolePermissionScript in $rolePermission.Script($scriptingOptions)) {
                                    #$roleScript = $rolePermission.Script($scriptingOptions)
                                    if ($rolePermission.ToString() -notin $roles) {
                                        $roles += , $rolePermission.ToString()
                                        $outsql += "$($rolePermissionScript.ToString())"
                                    }

                                }
                            }

                            #Database Create User(s) and add to Role(s)
                            foreach ($dbUserPermissionScript in $dbuser.Script($scriptingOptions)) {
                                if ($dbuserPermissionScript.Contains("sp_addrolemember")) {
                                    $execute = "EXEC "
                                }
                                else {
                                    $execute = ""
                                }
                                $outsql += "$execute$($dbUserPermissionScript.ToString())"
                            }

                            #Database Permissions
                            foreach ($databasePermission in $db.EnumDatabasePermissions() | Where-Object { @("sa", "dbo", "information_schema", "sys") -notcontains $_.Grantee -and $_.Grantee -notlike "##*" -and ($dbuser.Name -contains $_.Grantee) }) {
                                if ($databasePermission.PermissionState -eq "GrantWithGrant") {
                                    $withGrant = " WITH GRANT OPTION"
                                    $grantDatabasePermission = 'GRANT'
                                }
                                else {
                                    $withGrant = " "
                                    $grantDatabasePermission = $databasePermission.PermissionState.ToString().ToUpper()
                                }

                                $outsql += "$($grantDatabasePermission) $($databasePermission.PermissionType) TO [$($databasePermission.Grantee)]$withGrant AS [$($databasePermission.Grantor)];"
                            }


                            #Database Object Permissions
                            # NB: This is a bit of a mess for a couple of reasons
                            # 1. $db.EnumObjectPermissions() doesn't enumerate all object types
                            # 2. Some (x)Collection types can have EnumObjectPermissions() called
                            # on them directly (e.g. AssemblyCollection); others can't (e.g.
                            # ApplicationRoleCollection). Those that can't we iterate the
                            # collection explicitly and add each object's permission.

                            $perms = New-Object System.Collections.ArrayList

                            $null = $perms.AddRange($db.EnumObjectPermissions($dbuser.Name))

                            foreach ($item in $db.ApplicationRoles) {
                                $null = $perms.AddRange($item.EnumObjectPermissions($dbuser.Name))
                            }

                            foreach ($item in $db.Assemblies) {
                                $null = $perms.AddRange($item.EnumObjectPermissions($dbuser.Name))
                            }

                            foreach ($item in $db.Certificates) {
                                $null = $perms.AddRange($item.EnumObjectPermissions($dbuser.Name))
                            }

                            foreach ($item in $db.DatabaseRoles) {
                                $null = $perms.AddRange($item.EnumObjectPermissions($dbuser.Name))
                            }

                            foreach ($item in $db.FullTextCatalogs) {
                                $null = $perms.AddRange($item.EnumObjectPermissions($dbuser.Name))
                            }

                            foreach ($item in $db.FullTextStopLists) {
                                $null = $perms.AddRange($item.EnumObjectPermissions($dbuser.Name))
                            }

                            foreach ($item in $db.SearchPropertyLists) {
                                $null = $perms.AddRange($item.EnumObjectPermissions($dbuser.Name))
                            }

                            foreach ($item in $db.ServiceBroker.MessageTypes) {
                                $null = $perms.AddRange($item.EnumObjectPermissions($dbuser.Name))
                            }

                            foreach ($item in $db.RemoteServiceBindings) {
                                $null = $perms.AddRange($item.EnumObjectPermissions($dbuser.Name))
                            }

                            foreach ($item in $db.ServiceBroker.Routes) {
                                $null = $perms.AddRange($item.EnumObjectPermissions($dbuser.Name))
                            }

                            foreach ($item in $db.ServiceBroker.ServiceContracts) {
                                $null = $perms.AddRange($item.EnumObjectPermissions($dbuser.Name))
                            }

                            foreach ($item in $db.ServiceBroker.Services) {
                                $null = $perms.AddRange($item.EnumObjectPermissions($dbuser.Name))
                            }

                            if ($scriptVersion -ne "Version80") {
                                foreach ($item in $db.AsymmetricKeys) {
                                    $null = $perms.AddRange($item.EnumObjectPermissions($dbuser.Name))
                                }
                            }

                            foreach ($item in $db.SymmetricKeys) {
                                $null = $perms.AddRange($item.EnumObjectPermissions($dbuser.Name))
                            }

                            foreach ($item in $db.XmlSchemaCollections) {
                                $null = $perms.AddRange($item.EnumObjectPermissions($dbuser.Name))
                            }

                            foreach ($objectPermission in $perms | Where-Object { @("sa", "dbo", "information_schema", "sys") -notcontains $_.Grantee -and $_.Grantee -notlike "##*" -and $_.Grantee -eq $dbuser.Name }) {
                                switch ($objectPermission.ObjectClass) {
                                    'ApplicationRole' {
                                        $object = 'APPLICATION ROLE::[{0}]' -f $objectPermission.ObjectName
                                    }
                                    'AsymmetricKey' {
                                        $object = 'ASYMMETRIC KEY::[{0}]' -f $objectPermission.ObjectName
                                    }
                                    'Certificate' {
                                        $object = 'CERTIFICATE::[{0}]' -f $objectPermission.ObjectName
                                    }
                                    'DatabaseRole' {
                                        $object = 'ROLE::[{0}]' -f $objectPermission.ObjectName
                                    }
                                    'FullTextCatalog' {
                                        $object = 'FULLTEXT CATALOG::[{0}]' -f $objectPermission.ObjectName
                                    }
                                    'FullTextStopList' {
                                        $object = 'FULLTEXT STOPLIST::[{0}]' -f $objectPermission.ObjectName
                                    }
                                    'MessageType' {
                                        $object = 'Message Type::[{0}]' -f $objectPermission.ObjectName
                                    }
                                    'ObjectOrColumn' {
                                        if ($scriptVersion -ne "Version80") {
                                            $object = 'OBJECT::[{0}].[{1}]' -f $objectPermission.ObjectSchema, $objectPermission.ObjectName
                                            if ($null -ne $objectPermission.ColumnName) {
                                                $object += '([{0}])' -f $objectPermission.ColumnName
                                            }
                                        }
                                        #At SQL Server 2000 OBJECT did not exists
                                        else {
                                            $object = '[{0}].[{1}]' -f $objectPermission.ObjectSchema, $objectPermission.ObjectName
                                        }
                                    }
                                    'RemoteServiceBinding' {
                                        $object = 'REMOTE SERVICE BINDING::[{0}]' -f $objectPermission.ObjectName
                                    }
                                    'Schema' {
                                        $object = 'SCHEMA::[{0}]' -f $objectPermission.ObjectName
                                    }
                                    'SearchPropertyList' {
                                        $object = 'SEARCH PROPERTY LIST::[{0}]' -f $objectPermission.ObjectName
                                    }
                                    'Service' {
                                        $object = 'SERVICE::[{0}]' -f $objectPermission.ObjectName
                                    }
                                    'ServiceContract' {
                                        $object = 'CONTRACT::[{0}]' -f $objectPermission.ObjectName
                                    }
                                    'ServiceRoute' {
                                        $object = 'ROUTE::[{0}]' -f $objectPermission.ObjectName
                                    }
                                    'SqlAssembly' {
                                        $object = 'ASSEMBLY::[{0}]' -f $objectPermission.ObjectName
                                    }
                                    'SymmetricKey' {
                                        $object = 'SYMMETRIC KEY::[{0}]' -f $objectPermission.ObjectName
                                    }
                                    'User' {
                                        $object = 'USER::[{0}]' -f $objectPermission.ObjectName
                                    }
                                    'UserDefinedType' {
                                        $object = 'TYPE::[{0}].[{1}]' -f $objectPermission.ObjectSchema, $objectPermission.ObjectName
                                    }
                                    'XmlNamespace' {
                                        $object = 'XML SCHEMA COLLECTION::[{0}]' -f $objectPermission.ObjectName
                                    }
                                }

                                if ($objectPermission.PermissionState -eq "GrantWithGrant") {
                                    $withGrant = " WITH GRANT OPTION"
                                    $grantObjectPermission = 'GRANT'
                                }
                                else {
                                    $withGrant = " "
                                    $grantObjectPermission = $objectPermission.PermissionState.ToString().ToUpper()
                                }

                                $outsql += "$grantObjectPermission $($objectPermission.PermissionType) ON $object TO [$($objectPermission.Grantee)]$withGrant AS [$($objectPermission.Grantor)];"
                            }

                        }
                        catch {
                            Stop-Function -Message "This user may be using functionality from $($versionName[$db.CompatibilityLevel.ToString()]) that does not exist on the destination version ($versionNameDesc)." -Continue -InnerErrorRecord $_ -Target $db
                        }
                    }
                }
                else {
                    Write-Message -Level Output -Message "No users found on database '$db'"
                }

                #reset collection
                $users = $null
            }
        }
        else {
            Write-Message -Level Output -Message "No users found on instance '$server'"
        }
    }

    end {
        if (Test-FunctionInterrupt) { return }

        $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-SqlUser
    }
}