$port = Get-Random -Min 4200 -Max 42000
$JobName = "http://localhost:$($port)/"

$activitySource = New-ActivitySource -Name "littleweb"

New-TracerProviderBuilder |
Add-TracerSource -ActivitySource $activitySource |
Add-ResourceConfiguration -ServiceName $ExecutionContext.Host.Name -Attribute @{"host.name" = $(hostname); "host.port" = $port } |
Add-ExporterOtlpTrace -Endpoint http://localhost:4317 |
Add-ExporterConsole |
Start-Tracer

$httpListener = [Net.HttpListener]::new()
$httpListener.Prefixes.Add($JobName)
$httpListener.Start()

Start-ThreadJob -ScriptBlock {
    param($MainRunspace, $httpListener, $SourceIdentifier = 'http', $activitySource)
    while ($httpListener.IsListening) {
        $activity = $activitySource | Start-Activity -Name "Get Context" -Kind Server

        $contextAsync = $httpListener.GetContextAsync()
        while (-not ($contextAsync.IsCompleted -or $contextAsync.IsFaulted -or $contextAsync.IsCanceled)) {}
        if ($contextAsync.IsFaulted) {
            Write-Error -Exception $contextAsync.Exception -Category ProtocolError
            continue
        }

        $context = $(try { $contextAsync.Result } catch { $_ })

        $url = $context.Request.Url
        if ($url -match '/favicon.ico$') {
            $context.Response.StatusCode = 404
            $context.Response.Close()
            continue
        }

        $activity | Add-ActivityEvent -Message ("Generate Event. Url = {0}" -f $context.Request.Url)
        $MainRunspace.Events.GenerateEvent(
            $SourceIdentifier, $httpListener, @($context, $context.Request, $context.Response),
            [Ordered]@{Url = $context.Request.Url; Context = $context; Request = $context.Request; Response = $context.Response }
        )
        $activity.Stop()
    }
} -Name $JobName -ArgumentList ([Runspace]::DefaultRunspace, $httpListener, 'http', $activitySource) -ThrottleLimit 50 -InitializationScript { Import-Module potel } |
Add-Member -NotePropertyMembers ([Ordered]@{HttpListener = $httpListener }) -PassThru

Write-Host "Now Serving $jobName" -ForegroundColor Green

$rng = [Random]::new()
while ($httpListener.IsListening) {
    foreach ($event in @(Get-Event HTTP*)) {
        $activity = $activitySource | Start-Activity -Name "Process Event" -Kind Server
        $context, $request, $response = $event.SourceArgs
        if (-not $response.OutputStream) { continue }

        $response.Close($outputEncoding.GetBytes("$($rng.Next())"), $false)
        $activity | Add-ActivityEvent -Message "Responded to $($request.Url) in $([DateTime]::Now - $event.TimeGenerated)"
        $event | Remove-Event

        $activity.Stop()
    }
}

Stop-Tracer