wire:stream

wire:stream marks an element as the destination for content sent while an action is still running. This can show progress during a long request.

<?php

namespace Vendor\Module\Magewire;

use Magewirephp\Magewire\Component;

class ImportPreview extends Component
{
    public function preview(): void
    {
        $this->stream('preview-status', (string) __('Reading the file…'), true);

        // Call your Magento import-preview service here.
        // Keep actual imports and irreversible work in a dedicated service.

        $this->stream('preview-status', (string) __('Preview ready.'), true);
    }
}

<div>
    <button type="button" wire:click="preview">
        <?= $escaper->escapeHtml(__('Preview import')) ?>
    </button>
    <p wire:stream="preview-status" role="status"></p>
</div>

The third stream() argument replaces earlier content instead of appending. Do not assume that streamed output has reached the browser until the transport and hosting stack have been tested.

Magento output buffering

Magewire disables output buffering on the update controller for streaming actions, but PHP, the web server, or a proxy may still buffer the response. If updates appear only after the action finishes, check:

1. PHP output_buffering in php.ini or the FPM pool;
2. ob_* calls from observers or plugins;
3. web-server proxy buffering;
4. Varnish or CDN buffering on the update route.

Streaming changes how progress is displayed; it does not replace authorization, validation, or a job queue for work that outlives the request.