Compare checksum of files or directories.

Compare-DirectoryContents.ps1

function logMsg($text, $color = [System.ConsoleColor]::green) {
    Write-Host $text -foregroundcolor $color
    Write-Host "`r`n"
}

<#
function Remove-DirectoryPathInfo ($fileInfo) {
    $fileInfo.Path = $fileInfo.Path -replace "$([Regex]::Escape($testFiles[0].Parent.Parent.FullName))\\", ""
    $fileInfo.Path = $fileInfo.Path -replace "$([Regex]::Escape($initialFiles[0].Parent.Parent.FullName))\\", ""
    # "$([Regex]::Escape($parentDirectoryPath))\\"
    # "$([Regex]::Escape($parentDirectoryPath+'\'))"

    return $fileInfo
}
#>

function Get-Checksum {
    param(
        [Parameter(ValueFromPipeline = $true)]
        $files,
        [string[]]$ChecksumLogsPath = $null,
        [ValidateSet("MD5", "SHA1", "SHA256", "SHA384", "SHA512", "RIPEMD160", "MACTripleDES")]
        [string]$Algorithm = ("MD5", "SHA1", "SHA256", "SHA384", "SHA512", "RIPEMD160", "MACTripleDES")
    )

    BEGIN {
        function getFormattedFileHash ($filePath, $Algorithm) {
            $parentDirectoryPath = $file.DirectoryName                                                                                                       
            
            return Get-FileHash -LiteralPath $file.FullName -Algorithm $Algorithm | Select Hash, @{Name = 'FileName'; Expression = {$_.Path -replace "$([Regex]::Escape($parentDirectoryPath))\\", ""}}
        }

        $time = get-date
        $logFile = $($env:userprofile + "\checkSum-" + $time.ticks + ".log")
    }

    PROCESS {
        $files = $files | Where-Object { !$_.PSIsContainer }
        foreach ($file in $files) {
            $fileDeets = getFormattedFileHash -file $file -Algorithm $Algorithm
            
            ($fileDeets | Out-String).Trim() >> $logFile
        }
    }

    END {
        logMsg $("The checksum logfile was created: " + $logFile)
        # Invoke-Item $logFile

        return $logFile
    }
}

function Compare-Checksum ($checksumLogPaths) {
    logMsg "Generating hashes for each log file and comparing to the newly generated log hash..."
    # Leave the .Trim() otherwise .Equals comparison doesn't work properly.
    $checksumHashes = [psobject]@();

    foreach ($checksumLog in $checksumLogPaths) {
        # Does checksum log exist?
        $logExists = Test-Path $checksumLog
        if (!$logExists) {
            logMsg "This log file doesn't exist: $($checksumLog)" ([System.ConsoleColor]::red)
            continue;
        }

        # Verify checksums
        # Leave the .Trim() otherwise .Equals comparison doesn't work properly.
        $checksumHash = (Get-FileHash -LiteralPath $checksumLog -Algorithm SHA512 | Select-Object Hash).Hash
        $checksumHashes += $checksumHash

        Write-Host "Hash for $($checksumLog):" -ForegroundColor Green
        Write-Host "$checksumHash`r`n" -BackgroundColor Green
    }

    $isMatchingChecksums = @($checksumHashes | Select -Unique).Count -eq 1


    if ($isMatchingChecksums) {
        logMsg "These checksums match.`r`n$checksumLogPaths`r`n`r`n"
    }
    else {
        logMsg "These files are different:`r`n$checksumLogPaths`r`n$checksumHashes" ([System.ConsoleColor]::red)
    }
}


try {
    $initialPath = Read-Host -Prompt 'Give directory path...'
    $testPath = Read-Host -Prompt 'Give path to test against...'
    # C:\Users\mbramer\Documents\!src\infrastructure\

    $checksumLogPaths = @();

    $initialFiles =  Get-ChildItem -Path $initialPath -Recurse
    $testFiles =  Get-ChildItem -Path $testPath -Recurse

    $checksumLogPaths += ($initialFiles | Get-Checksum -Algorithm SHA256)
    $checksumLogPaths += ($testFiles | Get-Checksum -Algorithm SHA256)

    Compare-Checksum -checksumLogPaths $checksumLogPaths

} catch [Exception] {
    Write-Error $_
}

Get-FileHashIndex.ps1

function Get-FileHashIndex
{
<#
.Synopsis
   Get File Hash for PowerShell V3 and Higher
.DESCRIPTION
   Bringed C# how we retrieve File Hash to PowerShell Script.
   This works equivalent to Get-FileHash (v4) but twice as faster and supports -Recurse switch.

    measure-Command {Get-FileHashIndex -Path d:\test\test -Algorithm MACTripleDES -Recurse} # 684.4821
    measure-Command {Get-FileHashIndex -Path d:\test\test -Algorithm MD5 -Recurse} # 631.5687
    measure-Command {Get-FileHashIndex -Path d:\test\test -Algorithm RIPEMD160 -Recurse} # 693.6726
    measure-Command {Get-FileHashIndex -Path d:\test\test -Algorithm SHA1 -Recurse} # 641.9092
    measure-Command {Get-FileHashIndex -Path d:\test\test -Algorithm SHA256 -Recurse} # 695.2601
    measure-Command {Get-FileHashIndex -Path d:\test\test -Algorithm SHA384 -Recurse} # 677.8795
    measure-Command {Get-FileHashIndex -Path d:\test\test -Algorithm SHA512 -Recurse} # 685.4792
    measure-Command {ls d:\test\test -Recurse -File | Get-FileHashIndex -Algorithm MD5} # 878.1032
    measure-Command {ls d:\test\test -Recurse -File | Get-FileHash -Algorithm MD5} # 1364.2046
    measure-Command {ls d:\test\test -Recurse -File | Get-FileHash -Algorithm SHA256} # 1488.3237

.EXAMPLE
    PS > Get-FileHashIndex -Path d:\test\test -Algorithm MACTripleDES -Recurse

    Algorythm                                 Hash                                      Path
    ---------                                 ----                                      ----
    MACTripleDES                              40C3FEAAA71C928B2FC3D248F4DA86211FBC1726  D:\test\test\README.md
    MACTripleDES                              5DCE5F942594C97A9929D18507FB043FC23B917B  D:\test\test\hoge\Thumbs.db

.EXAMPLE
    PS > Get-FileHashIndex -Path d:\test\test -Algorithm MACTripleDES

    Algorythm                                 Hash                                      Path
    ---------                                 ----                                      ----
    MACTripleDES                              40C3FEAAA71C928B2FC3D248F4DA86211FBC1726  D:\test\test\README.md

.EXAMPLE
    PS > Get-FileHashIndex -Path d:\test\test -Algorithm MD5

    Algorythm                                 Hash                                      Path
    ---------                                 ----                                      ----
    MD5                                       7C865A164CE6DFC4AE0E61EED9A49B8E          D:\test\test\README.md

.EXAMPLE
    PS > Get-FileHashIndex -Path d:\test\test -Algorithm RIPEMD160

    Algorythm                                 Hash                                      Path
    ---------                                 ----                                      ----
    RIPEMD160                                 92DD18916AA074B0931E63D14541C44F07783CDF  D:\test\test\README.md

.EXAMPLE
    PS > Get-FileHashIndex -Path d:\test\test -Algorithm SHA1

    Algorythm                                 Hash                                      Path
    ---------                                 ----                                      ----
    SHA1                                      73A0294775D3A91F1EC91EEF58AD28C48A5B515A  D:\test\test\README.md

.EXAMPLE
    PS > Get-FileHashIndex -Path d:\test\test -Algorithm SHA256

    Algorythm                                 Hash                                      Path
    ---------                                 ----                                      ----
    SHA256                                    50DB8AFF8EFE10C9CBAAA2BE941E841AFF5ECC... D:\test\test\README.md

.EXAMPLE
    PS > Get-FileHashIndex -Path d:\test\test -Algorithm SHA384

    Algorythm                                 Hash                                      Path
    ---------                                 ----                                      ----
    SHA384                                    A8E66530035B84816C4C8BD2D4E17CC00D5848... D:\test\test\README.md

.EXAMPLE
    PS > Get-FileHashIndex -Path d:\test\test -Algorithm SHA512

    Algorythm                                 Hash                                      Path
    ---------                                 ----                                      ----
    SHA512                                    13A29B1D0C28ED69B441481282B3983F729D51... D:\test\test\README.md

.OUTPUTS
   [PSCustomObject]
   
   Incluide Algorithm, Hash and Path Property
#>

    [CmdletBinding()]
    param
    (
        [parameter(Mandatory = 1, Position = 0, ValueFromPipeline = 1, ValueFromPipelineByPropertyName =1)]
        [Alias("PSPath", "LiteralPath")]
        [string[]]$Path,

        [parameter(Mandatory = 0, Position = 1, ValueFromPipelineByPropertyName =1, ParameterSetName = "MD5")]
        [ValidateSet("MACTripleDES", "MD5", "RIPEMD160", "SHA1", "SHA256", "SHA384", "SHA512")]
        [string]$Algorithm = "SHA256",

        [parameter(Mandatory = 0, Position = 2, ValueFromPipelineByPropertyName =1)]
        [switch]$Recurse
    )

    process
    {
        foreach ($p in $Path){ $list.Add($p) }
    }

    end
    {
        foreach ($l in $list){ Get-ChildItem -Path $l -File -Recurse:$Recurse | GetHashInfo }
    }

    begin
    {
        $list = New-Object 'System.Collections.Generic.List[string]'

        filter GetHashInfo
        {
            try
            {
                [System.IO.FileStream]$stream = [System.IO.File]::OpenRead($_.fullname)
                $hash = GetHash -Stream $stream -Algorithm $Algorithm
            }
            finally
            {
                $stream.Dispose()
            }

            return [PSCustomObject]@{
                Algorithm = $Algorithm
                Hash = $hash
                Path = $_.FullName
                File = $_
            }
        }

        function GetHash ([System.IO.FileStream]$Stream, [string]$Algorithm)
        {
            try
            {
                $crypto = [System.Security.Cryptography.HashAlgorithm]::Create($Algorithm)
                [byte[]]$hash = $crypto.ComputeHash($Stream)
                return [System.BitConverter]::ToString($hash).Replace("-", [string]::Empty)
            }
            finally
            {
                $crypto.Dispose()
            }
        }

    }
}