Zero-dependency Powershell WebServer in a one file.

serve.ps1

# A zero-dependency tiny, copy-pasteable powershell web server for quick hacks
# Credit to https://woshub.com/simple-http-webserver-powershell/ for inspiration
# NOTE: If you download this script direclty, you will need to unblock it before running
#   Unblock-File .\serve.ps1
param (
  $webRoot = (Get-Location), # The folder from which to serve all files RECURSIVELY
  $listenHostname = "localhost", # Hostname to listen on. Change at your own risk.
  $listenPort = "9090" # The port to listen on.
)
# Needed for Content-Type header
Add-Type -AssemblyName "System.Web"
function Serve () {
  param (
    $webRoot = (Get-Location),
    $listenHostname = "localhost",
    $listenPort = "9090"
  )
  $listener = New-Object System.Net.HttpListener
  $listener.Prefixes.Add("http://${listenHostname}:${listenPort}/")
  $listener.Start()
  try {
    while (1 -eq 1) {
      try {
        $contextTask = $listener.GetContextAsync()
        while (-not $contextTask.AsyncWaitHandle.WaitOne(1000)) {}
        $context = $contextTask.GetAwaiter().GetResult()
        ServeFile $webRoot $context
      } catch {
        $context.Response.StatusCode = 500
        Log "$_`n$($_.ScriptStackTrace)"
      } finally {
        $context.Response.Close()
        Log "$($context.Request.HttpMethod) $($context.Request.RawUrl) => $($context.Response.StatusCode)"
      }
    }
  } catch {
    Log "$_`n$($_.ScriptStackTrace)"
  } finally {
    $listener.Close()
  }
}

function ServeFile() {
  param (
    [string] $webRoot,
    [System.Net.HttpListenerContext] $context
  )

  $contentPath = WebPathToFilePath $webRoot $context.Request.RawUrl
  if (Test-Path $contentPath -PathType Leaf) {
    $fileStream = New-Object System.IO.FileStream -ArgumentList $contentPath,3
    try {
      $fileStream.CopyTo($context.Response.OutputStream)
      $context.Response.StatusCode = 200
      $context.Response.ContentType = [System.Web.MimeMapping]::GetMimeMapping($contentPath)
    } finally {
      $fileStream.Close();
    }
  } else {
    $context.Response.StatusCode = 404
  }
}

function Log() {
  param (
    [string] $msg
  )
  $time = Get-Date -Format "yyyy-MM-dd HH:mm:ss.fffzzz"
  Write-Host "${time} | ${msg}"
}

function WebPathToFilePath() {
  param (
    [string] $webRoot,
    [string] $webPath
  )
  $webPath = $webPath.Replace("/", "\")
  return (Join-Path $webRoot $webPath)
}

Serve $webRoot $listenHostname $listenPort