Regular Expressions 101

Community Patterns

Connection String Parser

1

Regular Expression
PCRE2 (PHP >=7.3)

/
(?:(?'Key'[^\n][\w|\s]*)=(?'Value'[^;'"",`\n]+);?)
/
gm

Description

Parses connection strings into named groups Key and Value , which can then be handled by whatever programmatic method you like. Ideally handled as key value pairs.

I did this in PowerShell using the below:


function Resolve-ConnectionString {
  param(
    [string]$ConnectionString,
    [string[]]$IncludeKeys = @(),
    [switch]$HideSensitiveValues,
    [switch]$AsObject
  )
  begin {
    Write-Debug "Enter [$($PSCmdlet.MyInvocation.MyCommand.Name)]..."
    $PSBoundParameters.Keys.ForEach{
      if ($PSBoundParameters.PSItem -is [string]) {
        Write-Debug "$_ : $($PSBoundParameters.Item($_))"
      } else {
        Write-Debug "$_ : $($PSBoundParameters.Item($_).GetType())"
      }
    }
    $SensitiveValueKeys = [System.Collections.Generic.List[string]]::new([string[]]@(
        'AccountKey',
        'Password',
        'SharedAccessKey',
        'SharedAccessSignature',
        'Token',
        'PAT',
        'PersonalAccessToken',
        'AccessToken'
      ))
    # Example Connection Strings
    #     $testcontent2 = @"
    # AccountEndpoint=https://some-base-name.documents.azure.com:443/;AccountKey=kascuh9823nfsdvxc==;
    # Endpoint=sb://other-more-different-name.servicebus.windows.net/;SharedAccessKeyName=mysak-name;SharedAccessKey=msd8fs2bsc==;EntityPath=someentitypath;TransportType=Amqp
    # Data Source=myServerName.whatever.local;Initial Catalog=MyDatabaseName;Persist Security Info=True;User ID=myUserId;Password=MyBadPractice;MultipleActiveResultSets=True;MultiSubnetFailover=True;
    # "@
    $regexString = "(?:(?'Key'[^""\n][\w|\s]*)=(?'Value'[^;'"",`\n]+);?)"
  }
  process {
    if ($AsObject) {
      $output = [PSCustomObject]::new()
    } else {
      $output = @{}
    }
    if ($IncludeKeys.Count -gt 0) {
      $IncludeKeys.ForEach{
        Write-Debug "Adding key [$PSItem] to list of sensitive keys"
        $SensitiveValueKeys.Add($PSItem)
      }
    }
    Write-Debug "SensitiveValueKeys Count: $($SensitiveValueKeys.Count)"
    [regex]::Matches($ConnectionString, $regexString).foreach{
      $Key = $PSItem.Groups.Where({ $PSItem.Name -eq 'Key' })[0].Value
      $Value = $PSItem.Groups.Where({ $PSItem.Name -eq 'Value' })[0].Value
      Write-Debug "Key: [$($Key)]"
      Write-Debug "Value: [$($Value)]"
      $keyIsSensitive = ($SensitiveValueKeys | ForEach-Object {
          $Key -like "*$PSItem*"
        }).Contains($true)
      Write-Debug "Key is sensitive: [$($keyIsSensitive)]"
      if ($HideSensitiveValues -and $keyIsSensitive) {
        $Value = '********'
      } elseif ($keyIsSensitive) {
        Write-Warning "The value of [$($Key)] is sensitive and will be included in the output!!!"
      }
      if ($AsObject) {
        $output | Add-Member -MemberType NoteProperty -Name $Key -Value $Value -Force
      } else {
        $output.$Key = $Value
      }
    }
  }
  end {
    $output
    Write-Debug "Exit [$($PSCmdlet.MyInvocation.MyCommand.Name)]..."
  }

}

Submitted by rbleattler - 2 months ago