CSVValidator

1.0.0.0

Public/Test-CSVHeader.ps1

function Test-CSVHeader
{
    [CmdletBinding(SupportsShouldProcess = $false)]
    param
    (
        [Parameter(Mandatory = $true,
                   Position = 0)]
        [ValidatePattern('.csv')]
        [ValidateNotNullOrEmpty()]
        [ValidateScript({ test-path $_ })]
        [Alias('File', 'FilePath', 'csv', 'csvfile')]
        [string]$Path,
        [Parameter(Mandatory = $true,
                   Position = 1)]
        [ValidateNotNullOrEmpty()]
        [string[]]$Headers,
        [switch]$DisallowHeadersWithoutRules
    )
    
    #begin
    $rules = @{ }
    foreach ($item in $Headers)
    {
        $rules.add($item, $item)
    }
    $csvData = Import-Csv $Path
    try
    {
        $CSVHeader = $csvData[0] | Get-Member | where-object{ $_.MemberType -eq 'NoteProperty' }
    }
    catch
    {
        throw "There was no data in the CSV file $($Path). The script is unable to validate headers on this file."
    }
    $headersNotInRules = [System.Collections.ArrayList]@()
    $missingHeaders = [System.Collections.arraylist]@()
    $rulesResults = [pscustomobject]@{
        "HeadersInRules"  = $null
        "RulesAllPresent" = $null
        "CSVValid"          = $null
        "MissingHeaders"  = [System.Collections.arraylist]@()
    }
    #process
    foreach ($item in $CSVHeader.name)
    {
        if ($Rules.$($item))
        {
            #nothing right now
        }
        else
        {
            $headersNotInRules.add($item) | Out-Null
        }
    }
    
    foreach ($item in $Rules.keys)
    {
        if ($CSVHeader.name -contains $item)
        {
            #nothign right now
        }
        else
        {
            $missingHeaders.add($item) | Out-Null
            $rulesResults.missingHeaders.add($item) | Out-Null
        }
    }
    
    if ((($headersNotInRules | measure-object).count -gt 0) -and $DisallowHeadersWithoutRules)
    {
        Write-Warning "The CSV file $($Path) has headers which are not defined in the rules and the DisallowHeadersWithoutRules switch is present. This CSV file is not valid."
        $rulesResults.HeadersInRules = $false
    }
    elseif (($headersNotInRules | measure-object).count -gt 0)
    {
        Write-Verbose "The CSV file $($Path) has headers which are not defined in the rules. The switch DisallowHeadersWithoutRules is not given, therfore processing will continue as normal. Testing all of the rules now."
        $rulesResults.HeadersInRules = $true
    }
    else
    {
        Write-Verbose "All the headers in CSV file $($Path) are found in the rules. Testing all of the rules now."
        $rulesResults.headersInRules = $true
    }
    
    if (($missingHeaders | measure-object).count -gt 0)
    {
        Write-Warning "The CSV file $($Path) has defined headers in the ruleset which are not in the csv file"
        $rulesResults.rulesallpresent = $false
    }
    else
    {
        Write-Verbose "All of the headers defined in the rules are present in the CSV file"
        $rulesResults.rulesallpresent = $true
    }
    
    if ($rulesResults.rulesallpresent -eq $false -or $rulesResults.headersinrules -eq $false)
    {
        $rulesResults.csvValid = $false
    }
    else
    {
        $rulesResults.csvValid = $true
    }
    #end
    $rulesResults
}