FileContentResource.psm1

[DscResource()]
class FileContentResource {

    [DscProperty(Key)]
    [string] $filePath

    [DscProperty(Mandatory)]
    [string] $content

    [FileContentResource] Get()
    {
        $this.content = Get-Content -Path $this.filePath
        return $this
    }

    [void] Set()
    {
        Set-Content -Path $this.filePath -Value $this.Content
    }

    [bool] Test()
    {
        return (Get-Content -Path $this.filePath) -eq $this.content
    }
}