Fixed: Livewire File Upload "The file field is required" Error

The problem: Submitting a Livewire form with a file input throws a validation error saying the file field is required, even though a file was clearly selected in the browser.

Environment: Laravel 11, Livewire 3.x, PHP 8.3, WithFileUploads trait

The Error

● ● ●  validation response

Illuminate\Validation\ValidationException: The photo field is required.

Validator: photo => ["required"]
Request payload: photo = null

Why It Happens

Livewire handles file uploads differently from a normal HTML form — selecting a file doesn't submit it directly in the request payload like a traditional multipart form. Instead, Alpine's upload JS uploads the file to a temporary signed URL immediately on selection, and only then binds a reference to that temp file back to the Livewire property. If that upload step fails silently, or never fires, the property stays null and validation correctly (if confusingly) reports it as missing.

Three common causes:

1. Missing the WithFileUploads trait on the component class — without it, Livewire's JS still renders the file input, but the backend has no upload-handling machinery wired up to receive the temp file at all.

2. The temporary upload disk isn't configured or writable. Livewire stores temp uploads on the local disk under livewire-tmp/ by default — if this directory doesn't exist or isn't writable (common in fresh Docker/Sail containers), the temp upload silently fails.

3. Missing enctype isn't the issue (Livewire doesn't need it since it's not a real form submission), but a missing wire:model on the file input, or a typo mismatching the property name, means Livewire's JS has nothing to bind the uploaded temp file to.

The Fix

First, confirm the component uses the WithFileUploads trait:

app/Livewire/ProfileForm.php

use Livewire\Component;
use Livewire\WithFileUploads;

class ProfileForm extends Component
{
    use WithFileUploads;

    public $photo;

    public function save()
    {
        $this->validate([
            'photo' => 'required|image|max:2048',
        ]);

        $path = $this->photo->store('photos', 'public');
    }
}

Then confirm wire:model matches the property name exactly on the input:

<input type="file" wire:model="photo">

If the trait and binding are both correct, check that Livewire's temp upload directory exists and is writable:

mkdir -p storage/app/livewire-tmp
chmod -R 775 storage/app/livewire-tmp
php artisan storage:link

Also open the Network tab and look for a POST to /livewire/upload-file right after selecting the file — if that request never fires or returns an error, the issue is upload-side, not validation-side.

Step-by-Step

1. Add use WithFileUploads; to the Livewire component class if it's missing.
2. Confirm the wire:model attribute on the file input exactly matches the public property name.
3. Create and permission the temp upload folder: mkdir -p storage/app/livewire-tmp && chmod -R 775 storage/app/livewire-tmp.
4. Open DevTools Network tab, select a file, and confirm a POST /livewire/upload-file request fires and returns 200.
5. If that request fails, check storage/logs/laravel.log for the actual disk/permission error behind the scenes.
6. Resubmit the form and confirm the property is now populated and validation passes.

Edge case: If this only fails in production but works locally, check your filesystems.php config — if the local disk root points somewhere different in production (e.g. a mounted volume with different permissions on Forge/Vapor), the temp upload can fail silently there specifically, while your local Sail/Docker environment has no such restriction.

Still getting "field is required" after checking all this? Reach out on the Contact page and I'll help debug your upload setup.