Powershell Script - Compare Source Files - utility function to compare code between dev, prod, qa, bcp, etc.

BV-Compare_Source_Files.ps1

#Requires -Version 2.0
 
Function Compare-SourceFiles {
<#
.SYNOPSIS
Compares two directories and calculates any differences in files between them using MD5 hash comparison.
.DESCRIPTION
Only looks at full file paths, empty directories aren't scanned. 
.PARAMETER Source1
Full path (or UNC network share) to a directory to compare
.PARAMETER Source2
Full path (or UNC network share) to a directory to compare
.PARAMETER SummaryOnly
Displays only minimal information and a summary table
.PARAMETER ACLs
Compares security Descriptors (SDDLs) and security access control lists (ACLs). Only file ACLs are analyized (directories ignored).
.PARAMETER ReportFile
Outputs all analysis to a text file specified.
.EXAMPLE
Compare-SourceFiles -Source1 '\\CodeRepoServer\release\Prod' -Source2 '\\CodeRepoServer\release\Dev' -ReportFile 'c:\temp\differenceReport.log'
This will generate an output report of the different files between two code releases
.EXAMPLE
Compare-SourceFiles -Source1 '\\webserver1\c$\webapp\wwwroot' -Source2 '\\webserver2\c$\webapp\wwwroot' -ACLs -SummaryOnly
This creates a summary of the differences between two webservers, also checking for ACL differences.
.LINK
http://www.bryanvine.com/2015/06/powershell-script-compare-sourcefiles.html
.LINK
Compare-Object
.LINK
Get-ACL
.NOTES
Author: Bryan Vine
Last updated: 6/28/2015
#>
    [CmdletBinding()]
    Param(
        [Parameter(Mandatory=$true,valuefrompipeline=$false,Position=0)]
        [ValidateNotNullOrEmpty()][string]
        $Source1,

        [Parameter(Mandatory=$true,valuefrompipeline=$false,Position=0)]
        [ValidateNotNullOrEmpty()][string]
        $Source2,

        [switch]$SummaryOnly,
        [switch]$ACLs,
        [string]$ReportFile
    )
    
    #if Powershell v4 or later, use faster file searcher, otherwise use slower where filter
    if($host.Version.Major -gt 3){
        $filelist1 = dir -Recurse $Source1 -File | select -ExpandProperty fullname | ForEach-Object{$_.replace($Source1,"")}
        $filelist2 = dir -Recurse $Source2 -File | select -ExpandProperty fullname | ForEach-Object{$_.replace($Source2,"")}
    }
    else{
        $filelist1 = dir -Recurse $Source1 | Where-Object{$_.mode -notlike 'd*'} | select -ExpandProperty fullname | ForEach-Object{$_.replace($Source1,"")}
        $filelist2 = dir -Recurse $Source2 | Where-Object{$_.mode -notlike 'd*'} | select -ExpandProperty fullname | ForEach-Object{$_.replace($Source2,"")}
    }

    #Counters
    $DifferentFiles = 0
    if($ACLs){
        $DifferentACLs = 0
        $DifferentSDDLs = 0
    }

    if($ReportFile){
        $Report = @()
        $Report += "Comparing '$Source1' and '$Source2'"
        $Report += ''
    }
    
    #compare filenames
    $FileNameCompare = Compare-Object -ReferenceObject $filelist1 -DifferenceObject $filelist2 -IncludeEqual
    

    $Missing1 = $FileNameCompare | Where-Object{$_.SideIndicator -like "=>"} | Select -ExpandProperty InputObject
    if($Missing1){
        Write-Warning "Files missing from '$Source1': $($Missing1.count)"
        if($ReportFile){
            $Report += "Files missing from '$Source1': $($Missing1.count)"
            $Report += $Missing1
            $Report += ''
            $Report += ''
        }
        if(!$SummaryOnly){
            Write-Host ($Missing1 | Out-String)
            Write-Host ''
            Write-Host ''
        }
    }

    $Missing2 = $FileNameCompare | Where-Object{$_.SideIndicator -like "<="} | Select -ExpandProperty InputObject
    if($Missing2){
        Write-Warning "Files missing from '$Source2': $($Missing2.count)"
        if($ReportFile){
            $Report += "Files missing from '$Source2': $($Missing2.count)"
            $Report += $Missing2
            $Report += ''
            $Report += ''
        }
        if(!$SummaryOnly){
            Write-Host ($Missing2 | Out-String)
            Write-Host ''
            Write-Host ''    
        }
    }

    #For shared filenames, iterate through them to compare further
    $SharedFiles = $FileNameCompare | Where-Object{$_.SideIndicator -like "=="} | Select -ExpandProperty InputObject
    $SharedFiles | ForEach-Object{
    
        #Compare MD5 Hashes
        $hashes = "$Source1$_","$Source2$_" | ForEach-Object{
                    $MD5 = [Security.Cryptography.HashAlgorithm]::Create( "MD5" )
                    $stream = ([IO.StreamReader]"$_").BaseStream
                    -join ($MD5.ComputeHash($stream) | ForEach-Object { "{0:x2}" -f $_ })
                    $stream.Close()
        }
        
        #Hashes aren't the same
        if ($hashes[0] -ne $hashes[1]){
            $DifferentFiles++
            Write-Warning "File Hash different: '$_'"
            if($ReportFile){
                $Report += "File Hash different: '$_'"
            }

            if($_ -notlike "*.exe" -and $_ -notlike "*.dll"){
                #Attempt to do text comparison and display different lines
                $dif = diff -ReferenceObject (Get-Content "$Source1$_") -DifferenceObject (Get-Content "$Source2$_")
                if(!$SummaryOnly){write-Host ($dif | Out-String)}
                if($ReportFile){
                    $Report += ($dif | Out-String)
                }

            }

            if(!$SummaryOnly){
                Write-Host ''
                Write-Host ''   
            }
            if($Report){
                $Report += ''
                $Report += ''
            }
        }
 
            
        #Compare ACLs
        if($ACLs){
            $acl1 = Get-Acl "$Source1$_"
            $acl2 = Get-Acl "$Source2$_"
            if($acls1.sddl -ne $acls2.sddl){
                Write-Warning "ACL Security descriptor different: '$_'"
                $DifferentSDDLs++
                if(!$SummaryOnly){
                    Write-Host ''
                    Write-Host ''   
                }
                if($ReportFile){
                    $Report += "ACL Security descriptor different: '$_'"
                    $Report += ''
                    $Report += ''
                }
            }

            #compute access differences
            $Access = Compare-Object -ReferenceObject $acl1 -DifferenceObject $acl2 -Property Access -PassThru -ErrorAction SilentlyContinue
            if($Access){
                Write-Warning "ACL Access Permissions different: '$_'"
                $DifferentACLs++
                if(!$SummaryOnly){
                    Write-Host "   File Permissions: '$Source1$_'"
                    Write-Host ($Access[0].Access | sort IdentityReference | Format-Table -AutoSize| Out-String)
                    Write-Host "   File Permissions: '$Source2$_'"
                    Write-Host ($Access[1].Access | sort IdentityReference | Format-Table -AutoSize| Out-String)
                    Write-Host ''
                    Write-Host ''   
                }
                if($ReportFile){
                    $Report += "ACL Access Permissions different: '$_'"
                    $Report += "   File Permissions: '$Source1$_'"
                    $Report += ($Access[0].Access | sort IdentityReference | Format-Table -AutoSize| Out-String)
                    $Report += "   File Permissions: '$Source2$_'"
                    $Report += ($Access[1].Access | sort IdentityReference | Format-Table -AutoSize| Out-String)
                    $Report += ''
                    $Report += ''
                }
            }
        }
    }

    #Build Summary output
    
    $S1Obj = New-Object PSObject
    $S2Obj = New-Object PSObject
    $S1Obj | Add-Member NoteProperty Path $Source1
    $S1Obj | Add-Member NoteProperty FileCount $filelist1.count
    $S1Obj | Add-Member NoteProperty MissingFiles $Missing1.Count
    $S2Obj | Add-Member NoteProperty Path $Source2
    $S2Obj | Add-Member NoteProperty FileCount $filelist2.count
    $S2Obj | Add-Member NoteProperty MissingFiles $Missing2.Count
    $S1Obj,$S2Obj | Add-Member NoteProperty SharedFiles $SharedFiles.Count
    $S1Obj,$S2Obj | Add-Member NoteProperty DifferentHashes $DifferentFiles
    if($ACLs){
        if($DifferentSDDLs){
            $S1Obj,$S2Obj | Add-Member NoteProperty DifferentSDDL $DifferentSDDLs
        }
        $S1Obj,$S2Obj | Add-Member NoteProperty DifferentACLs $DifferentACLs
    }
    $SummaryReport = @()
    $SummaryReport += $S1Obj
    $SummaryReport += $S2Obj

    Write-Host ''
    Write-Host '=============================='
    Write-Host 'File Source Comparison Summary'  
    Write-Host '=============================='
    Write-Output $SummaryReport | FT -AutoSize

    if($ReportFile){
        
        $Report += ''
        $Report += '=============================='
        $Report += 'File Source Comparison Summary'  
        $Report += '=============================='
        $Report += ($SummaryReport | FT -AutoSize | Out-String)

        $Report | Set-Content $ReportFile
    }
}