functions/Get-DbaBackupInformation.ps1

#ValidationTags#Messaging,FlowControl,Pipeline,CodeStyle#
function Get-DbaBackupInformation {
    <#
        .SYNOPSIS
            Scan backup files and creates a set, compatible with Restore-DbaDatabase
 
        .DESCRIPTION
            Upon being passed a list of potential backups files this command will scan the files, select those that contain SQL Server
            backup sets. It will then filter those files down to a set
 
            The function defaults to working on a remote instance. This means that all paths passed in must be relative to the remote instance.
            XpDirTree will be used to perform the file scans
 
            Various means can be used to pass in a list of files to be considered. The default is to non recursively scan the folder
            passed in.
 
        .PARAMETER Path
            Path to SQL Server backup files.
 
            Paths passed in as strings will be scanned using the desired method, default is a non recursive folder scan
            Accepts multiple paths separated by ','
 
            Or it can consist of FileInfo objects, such as the output of Get-ChildItem or Get-Item. This allows you to work with
            your own file structures as needed
 
        .PARAMETER SqlInstance
            The SQL Server instance to be used to read the headers of the backup files
 
        .PARAMETER SqlCredential
            Allows you to login to servers using SQL Logins as opposed to Windows Auth/Integrated/Trusted.
 
        .PARAMETER DatabaseName
            An array of Database Names to filter by. If empty all databases are returned.
 
        .PARAMETER SourceInstance
            If provided only backup originating from this destination will be returned. This SQL instance will not be connected to or involved in this work
 
        .PARAMETER NoXpDirTree
            If this switch is set, then Files will be parsed as locally files. This can cause failures if the running user can see files that the parsing SQL Instance cannot
 
        .PARAMETER DirectoryRecurse
            If specified the provided path/directory will be traversed (only applies if not using XpDirTree)
 
        .PARAMETER Anonymise
            If specified we will output the results with ComputerName, InstanceName, Database, UserName, and Paths hashed out
            This options is mainly for use if we need you to submit details for fault finding to the dbatools team
 
        .PARAMETER ExportPath
            If specified the output will export via CliXml format to the specified file. This allows you to store the backup history object for later usage, or move it between computers
 
        .PARAMETER NoClobber
            If specified will stop Export from overwriting an existing file, the default is to overwrite
 
        .PARAMETER PassThru
            When data is exported the cmdlet will return no other output, this switch means it will also return the normal output which can be then piped into another command
 
        .PARAMETER MaintenanceSolution
            This switch tells the function that the folder is the root of a Ola Hallengren backup folder
 
        .PARAMETER IgnoreLogBackup
            This switch only works with the MaintenanceSolution switch. With an Ola Hallengren style backup we can be sure that the LOG folder contains only log backups and skip it.
            For all other scenarios we need to read the file headers to be sure.
 
        .PARAMETER AzureCredential
            The name of the SQL Server credential to be used if restoring from an Azure hosted backup
 
        .PARAMETER Import
            When specified along with a path the command will import a previously exported BackupHistory object from an xml file.
 
        .PARAMETER EnableException
            Replaces user friendly yellow warnings with bloody red exceptions of doom!
            Use this if you want the function to throw terminating errors you want to catch.
 
        .EXAMPLE
            Get-DbaBackupInformation -SqlInstance Server1 -Path c:\backups\ -DirectoryRecurse
 
            Will use the Server1 instance to recursively read all backup files under c:\backups, and return a dbatools BackupHistory object
 
        .NOTES
            Tags: DisasterRecovery, Backup, Restore
 
            dbatools PowerShell module (https://dbatools.io)
            Copyright (C) 2016 Chrissy LeMaire
            License: MIT https://opensource.org/licenses/MIT
 
        .LINK
            https://dbatools.io/Get-DbaBackupInformation
 
        .EXAMPLE
            Get-DbaBackupInformation -SqlInstance Server1 -Path c:\backups\ -DirectoryRecurse -ExportPath c:\store\BackupHistory.xml
 
            #Copy the file c:\store\BackupHistory.xml to another machine via preferred technique, and the on 2nd machine:
 
            Get-DbaBackupInformation -Import -Path c:\store\BackupHistory.xml | Restore-DbaDatabase -SqlInstance Server2 -TrustDbBackupHistory
 
            This allows you to move backup history across servers, or to preserve backup history even after the original server has been purged
 
        .EXAMPLE
            Get-DbaBackupInformation -SqlInstance Server1 -Path c:\backups\ -DirectoryRecurse -ExportPath c:\store\BackupHistory.xml -PassThru |
                    Restore-DbaDatabase -SqlInstance Server2 -TrustDbBackupHistory
 
            In this example we gather backup information, export it to an xml file, and then pass it on through to Restore-DbaDatabase
            This allows us to repeat the restore without having to scan all the backup files again
 
        .EXAMPLE
            Get-ChildItem c:\backups\ -recurse -files |
                Where {$_.extension -in ('.bak','.trn') -and $_.LastWriteTime -gt (get-date).AddMonths(-1)} |
                Get-DbaBackupInformation -SqlInstance Server1 -ExportPath c:\backupHistory.xml
 
            This lets you keep a record of all backup history from the last month on hand to speed up refreshes
 
        .EXAMPLE
            $Backups = Get-DbaBackupInformation -SqlInstance Server1 -Path \\network\backups
            $Backups += Get-DbaBackupInformation -SqlInstance Server2 -NoXpDirTree -Path c:\backups
 
            Scan the unc folder \\network\backups with Server1, and then scan the C:\backups folder on
            Server2 not using xp_dirtree, adding the results to the first set.
 
        .EXAMPLE
            $Backups = Get-DbaBackupInformation -SqlInstance Server1 -Path \\network\backups -MaintenanceSolution
 
            When MaintenanceSolution is indicated we know we are dealing with the output from Ola Hallengren's backup scripts. So we make sure that a FULL folder exists in the first level of Path, if not we shortcut scanning all the files as we have nothing to work with
 
        .EXAMPLE
            $Backups = Get-DbaBackupInformation -SqlInstance Server1 -Path \\network\backups -MaintenanceSolution -IgnoreLogBackup
 
            As we know we are dealing with an Ola Hallengren style backup folder from the MaintenanceSolution switch, when IgnoreLogBackup is also included we can ignore the LOG folder to skip any scanning of log backups. Note this also means then WON'T be restored
    #>

    [CmdletBinding( DefaultParameterSetName = "Create")]
    param (
        [parameter(Mandatory = $true, ValueFromPipeline = $true)]
        [object[]]$Path,
        [parameter(Mandatory = $true, ParameterSetName = "Create")]
        [Alias("ServerInstance", "SqlServer")]
        [DbaInstanceParameter]$SqlInstance,
        [parameter(ParameterSetName = "Create")]
        [PSCredential]$SqlCredential,
        [string[]]$DatabaseName,
        [string[]]$SourceInstance,
        [parameter(ParameterSetName = "Create")]
        [Switch]$NoXpDirTree,
        [parameter(ParameterSetName = "Create")]
        [switch]$DirectoryRecurse,
        [switch]$EnableException,
        [switch]$MaintenanceSolution,
        [switch]$IgnoreLogBackup,
        [string]$ExportPath,
        [string]$AzureCredential,
        [parameter(ParameterSetName = "Import")]
        [switch]$Import,
        [switch][Alias('Anonymize')]$Anonymise,
        [Switch]$NoClobber,
        [Switch]$PassThru

    )
    begin {
        function Get-HashString {
            param(
                [String]$InString
            )

            $StringBuilder = New-Object System.Text.StringBuilder
            [System.Security.Cryptography.HashAlgorithm]::Create("md5").ComputeHash([System.Text.Encoding]::UTF8.GetBytes($InString))| ForEach-Object {
                [Void]$StringBuilder.Append($_.ToString("x2"))
            }
            return $StringBuilder.ToString()
        }
        Write-Message -Level InternalComment -Message "Starting"
        Write-Message -Level Debug -Message "Parameters bound: $($PSBoundParameters.Keys -join ", ")"

        if (Test-Bound -ParameterName ExportPath) {
            if ($true -eq $NoClobber) {
                if (Test-Path $ExportPath) {
                    Stop-Function -Message "$ExportPath exists and NoClobber set"
                    return
                }
            }
        }
        if ($PSCmdlet.ParameterSetName -eq "Create") {
            try {
                $server = Connect-SqlInstance -SqlInstance $SqlInstance -SqlCredential $SqlCredential
            }
            catch {
                Stop-Function -Message "Failure" -Category ConnectionError -ErrorRecord $_ -Target $instance -Continue
                return
            }
        }

        if ($true -eq $IgnoreLogBackup -and $true -ne $MaintenanceSolution) {
            Write-Message -Message "IgnoreLogBackup can only by used with MaintenanceSolution. Will not be used" -Level Warning
        }
    }
    process {
        if (Test-FunctionInterrupt) { return }
        if ((Test-Bound -Parameter Import) -and ($true -eq $Import)) {
            foreach ($f in $Path) {
                if (Test-Path -Path $f) {
                    $GroupResults += Import-CliXml -Path $f
                    foreach ($group in  $GroupResults) {
                        $Group.FirstLsn = [BigInt]$group.FirstLSN.ToString()
                        $Group.CheckpointLSN = [BigInt]$group.CheckpointLSN.ToString()
                        $Group.DatabaseBackupLsn = [BigInt]$group.DatabaseBackupLsn.ToString()
                        $Group.LastLsn = [BigInt]$group.LastLsn.ToString()
                    }
                }
                else {
                    Write-Message -Message "$f does not exist or is unreadable" -Level Warning
                }
            }
        }
        else {
            $Files = @()
            $groupResults = @()
            if ($Path[0] -match 'http') { $NoXpDirTree = $true }
            if ($NoXpDirTree -ne $true) {
                foreach ($f in $path) {
                    if ([System.IO.Path]::GetExtension($f).Length -gt 1) {
                        if ("Fullname" -notin $f.PSobject.Properties.name) {
                            $f = $f | Select-Object *, @{ Name = "FullName"; Expression = { $f } }
                        }
                        Write-Message -Message "Testing a single file $f " -Level Verbose
                        if ((Test-DbaSqlPath -Path $f.fullname -SqlInstance $server)) {
                            $files += $f
                        }
                        else {
                            Write-Message -Level Verbose -Message "$server cannot 'see' file $($f.FullName)"
                        }
                    }
                    elseif ($True -eq $MaintenanceSolution) {
                        if ($true -eq $IgnoreLogBackup -and [System.IO.Path]::GetDirectoryName($f) -like '*LOG') {
                            Write-Message -Level Verbose -Message "Skipping Log Backups as requested"
                        }
                        else {
                            Write-Message -Level Verbose -Message "OLA - Getting folder contents"
                            $Files += Get-XpDirTreeRestoreFile -Path $f -SqlInstance $server
                        }
                    }
                    else {
                        Write-Message -Message "Testing a folder $f" -Level Verbose
                        $Files += $Check = Get-XpDirTreeRestoreFile -Path $f -SqlInstance $server
                        if ($null -eq $check) {
                            Write-Message -Message "Nothing returned from $f" -Level Verbose
                        }
                    }
                }
            }
            else {
                ForEach ($f in $path) {
                    Write-Message -Level VeryVerbose -Message "Not using sql for $f"
                    if ($f -is [System.IO.FileSystemInfo]) {
                        if ($f.PsIsContainer -eq $true -and $true -ne $MaintenanceSolution) {
                            Write-Message -Level VeryVerbose -Message "folder $($f.fullname)"
                            $Files += Get-ChildItem -Path $f.fullname -File -Recurse:$DirectoryRecurse
                        }
                        elseif ($f.PsIsContainer -eq $true -and $true -eq $MaintenanceSolution) {
                            if ($IgnoreLogBackup -and $f -notlike '*LOG' ) {
                                Write-Message -Level Verbose -Message "Skipping Log backups for Maintenance backups"
                            }
                            else {
                                $Files += Get-ChildItem -Path $f.fullname -File -Recurse:$DirectoryRecurse
                            }
                        }
                        elseif ($true -eq $MaintenanceSolution) {
                            $Files += Get-ChildItem -Path $f.fullname -Recurse:$DirectoryRecurse
                        }
                        else {
                            Write-Message -Level VeryVerbose -Message "File"
                            $Files += $f.fullname
                        }
                    }
                    else {
                        if ($true -eq $MaintenanceSolution) {
                            $Files += Get-XpDirTreeRestoreFile -Path $f\FULL -SqlInstance $server -NoRecurse
                            $Files += Get-XpDirTreeRestoreFile -Path $f\DIFF -SqlInstance $server -NoRecurse
                            $Files += Get-XpDirTreeRestoreFile -Path $f\LOG -SqlInstance $server -NoRecurse
                        }
                        else {
                            Write-Message -Level VeryVerbose -Message "File"
                            $Files += $f
                        }
                    }
                }
            }

            if ($True -eq $MaintenanceSolution -and $True -eq $IgnoreLogBackup) {
                Write-Message -Level Verbose -Message "Skipping Log Backups as requested"
                $Files = $Files | Where-Object {$_.FullName -notlike '*\LOG\*'}
            }

            Write-Message -Level Verbose -Message "Reading backup headers of $($Files.Count) files"
            try {
                $FileDetails = Read-DbaBackupHeader -SqlInstance $server -Path $Files -AzureCredential $AzureCredential -EnableException
            }
            catch {
                Stop-Function -Message "Failure reading backup header" -ErrorRecord $_ -Target $server -Continue
            }
            
            $groupdetails = $FileDetails | group-object -Property BackupSetGUID

            foreach ($Group in $GroupDetails) {
                $historyObject = New-Object Sqlcollaborative.Dbatools.Database.BackupHistory
                $historyObject.ComputerName = $group.group[0].MachineName
                $historyObject.InstanceName = $group.group[0].ServiceName
                $historyObject.SqlInstance = $group.group[0].ServerName
                $historyObject.Database = $group.Group[0].DatabaseName
                $historyObject.UserName = $group.Group[0].UserName
                $historyObject.Start = [DateTime]$group.Group[0].BackupStartDate
                $historyObject.End = [DateTime]$group.Group[0].BackupFinishDate
                $historyObject.Duration = ([DateTime]$group.Group[0].BackupFinishDate - [DateTime]$group.Group[0].BackupStartDate)
                $historyObject.Path = [string[]]$Group.Group.BackupPath
                $historyObject.FileList = ($group.Group.FileList | select-object Type, LogicalName, PhysicalName)
                $historyObject.TotalSize = ($Group.Group.BackupSize | Measure-Object -Sum).Sum
                $HistoryObject.CompressedBackupSize = ($Group.Group.CompressedBackupSize | Measure-Object -Sum).Sum
                $historyObject.Type = $group.Group[0].BackupTypeDescription
                $historyObject.BackupSetId = $group.group[0].BackupSetGUID
                $historyObject.DeviceType = 'Disk'
                $historyObject.FullName = $Group.Group.BackupPath
                $historyObject.Position = $group.Group[0].Position
                $historyObject.FirstLsn = $group.Group[0].FirstLSN
                $historyObject.DatabaseBackupLsn = $group.Group[0].DatabaseBackupLSN
                $historyObject.CheckpointLSN = $group.Group[0].CheckpointLSN
                $historyObject.LastLsn = $group.Group[0].LastLsn
                $historyObject.SoftwareVersionMajor = $group.Group[0].SoftwareVersionMajor
                $historyObject.RecoveryModel = $group.Group.RecoveryModel
                $groupResults += $historyObject
            }
        }
        if (Test-Bound 'SourceInstance') {
            $groupResults = $groupResults | Where-Object {$_.InstanceName -in $SourceInstance}
        }

        if (Test-Bound 'DatabaseName') {
            $groupResults = $groupResults | Where-Object {$_.Database -in $DatabaseName}
        }
        if ($true -eq $Anonymise) {
            foreach ($group in $GroupResults) {
                $group.ComputerName = Get-HashString -InString $group.ComputerName
                $group.InstanceName = Get-HashString -InString $group.InstanceName
                $group.SqlInstance = Get-HashString -InString $group.SqlInstance
                $group.Database = Get-HashString -InString $group.Database
                $group.UserName = Get-HashString -InString $group.UserName
                $group.Path = Get-HashString -InString  $Group.Path
                $group.FullName = Get-HashString -InString $Group.Fullname
            }
        }
        if ((Test-Bound -parameterName exportpath) -and $null -ne $ExportPath) {
            $groupResults | Export-CliXml -Path $ExportPath -Depth 5 -NoClobber:$NoClobber
            if ($true -ne $PassThru) {
                return
            }
        }
        $groupResults | Sort-Object -Property End -Descending
    }
}