Forum Discussion

Copper Contributor

Sep 08, 2022

Need to compare only specific lines

Hi, Can someone help to write a script to compare only few required lines between configuration files. For example if file1 has key value pair stating abc=123, it should compare with another file fil...

Script for Compare only specified lines

VinayNaguru

Copper Contributor

Sep 08, 2022

Hi Harm_Veenstra,

Sure. Below is the part of the script. Script need to identify only the lines which doesn't have '#' and highlighted in red color (there is no color code in original file. Highlighted by me for easy identification)

# This parameter defines whether to use CORS filter on Auth server security filter chain.

# This parameter can only be set during initialization.

# Default=true

# auth.enable.corsfilter=true

auth.enable.corsfilter=true

# This parameter defines the number of days that a user can keep a password before it is expired

# This parameter can only be set during initialization.

# Default=60

# auth.password.expiration.days=60

auth.password.expiration.days=60

# This parameter defines the number of previous passwords that cannot be used for a new password.

# This parameter can only be set during initialization.

# Default=1

# auth.password.history.size=1

auth.password.history.size=1

Harm_Veenstra

MVP

Sep 08, 2022

VinayNaguru I made a very simple compare

$file1 = get-content .\file1.txt
$file2 = get-content .\file2.txt
$contentsfile1 = @()

foreach ($line in $file1) {
    if ($line.StartsWith('#')) {
        #Skip
    }
    else {
        if ($line.Contains('=')) {
            $contentsfile1 += $line
        }
    }
}

foreach ($value in $contentsfile1) {
    if (-not ($file2 | Select-String $value)) {
        $found = $file2 | Select-String $value.Split('=')[0] | Select-String -Pattern '#' -NotMatch
        write-host ("{0} not found, value found is {1}" -f $value, $found) -ForegroundColor Red
    
    }
}

Contents file 1

# This parameter defines whether to use CORS filter on Auth server security filter chain.
# This parameter can only be set during initialization.
#
# Default=true
#
# auth.enable.corsfilter=true
auth.enable.corsfilter=false

# This parameter defines the number of days that a user can keep a password before it is expired
# This parameter can only be set during initialization.
#
# Default=60
#
# auth.password.expiration.days=60
auth.password.expiration.days=30

# This parameter defines the number of previous passwords that cannot be used for a new password.
# This parameter can only be set during initialization.
#
# Default=1
#
# auth.password.history.size=1
auth.password.history.size=2

Contents File 2

# This parameter defines whether to use CORS filter on Auth server security filter chain.
# This parameter can only be set during initialization.
#
# Default=true
#
# auth.enable.corsfilter=true
auth.enable.corsfilter=true

# This parameter defines the number of days that a user can keep a password before it is expired
# This parameter can only be set during initialization.
#
# Default=60
#
# auth.password.expiration.days=60
auth.password.expiration.days=60

# This parameter defines the number of previous passwords that cannot be used for a new password.
# This parameter can only be set during initialization.
#
# Default=1
#
# auth.password.history.size=1
auth.password.history.size=1

Output on screen:
auth.enable.corsfilter=false not found, value found is auth.enable.corsfilter=true
auth.password.expiration.days=30 not found, value found is auth.password.expiration.days=60
auth.password.history.size=2 not found, value found is auth.password.history.size=1

VinayNaguru
Copper Contributor
Sep 08, 2022
Hi Harm_Veenstra,

Wow. Let me try the scenario. Thank you so much for help me.
- Harm_Veenstra
  MVP
  Sep 08, 2022
  Let us know the results 🙂
  - VinayNaguru
    Copper Contributor
    Sep 10, 2022
    It worked for text and config files. But not working for the Yaml file. So it will be different for it?

LainRobertson

Silver Contributor

Sep 08, 2022

VinayNaguru Harm_Veenstra

I went for something a little more complex. May be overkill for this scenario but here it is anyway.

function Get-FileDifferences([string]$SourceFile, [string]$TargetFile)
{
    if ((Test-Path -Path $SourceFile) -and (Test-Path -Path $TargetFile))
    {
        $TargetHashes = [System.Collections.Generic.Dictionary[[int], [string]]]::new();

        # Read the target file first.
        Get-Content -Path $TargetFile |
            ForEach-Object {
                if (-not [string]::IsNullOrWhiteSpace($_) -and -not $_.Replace(" ", "").StartsWith("#") -and -not $TargetHashes.ContainsKey(($Hash = $_.GetHashCode())))
                {
                    $null = $TargetHashes.Add($Hash, $_);
                }
            }

        # Read the source file and prune matching items as we go, while reporting any differences.
        Get-Content -Path $SourceFile |
            ForEach-Object {
                if (-not [string]::IsNullOrWhiteSpace($_) -and -not $_.Replace(" ", "").StartsWith("#"))
                {
                    if ($TargetHashes.ContainsKey(($Hash = $_.GetHashCode())))
                    {
                        $null = $TargetHashes.Remove($Hash);
                    }
                    else
                    {
                        [PSCustomObject] @{
                            File = "Source";
                            Variation = $_;
                        }
                    }
                }
            }

        # List anything remaining in $TargetHashes as these are implicitly the differences.
        if ($TargetHashes.Count -gt 0)
        {
            foreach ($Entry in $TargetHashes.GetEnumerator())
            {
                [PSCustomObject] @{
                    File = "Target";
                    Variation = $Entry.Value;
                }
            }
        }
    }
    else
    {
        throw "One or both files were not found.";
    }
}

With the output looking like:

I simply used directory listing for the two source files but it doesn't matter what format they are - so long as they're text and not binary.

Cheers,

Lain

VinayNaguru
Copper Contributor
Sep 08, 2022
Hi Lain. Wow. I will try your script too. Thank you for help me and making my work easier.