Trimming Filament Strings Globally

When I first started using Laravel, I really didn’t like the global middleware that trimmed strings. But after a while, it became an irreplaceable part of my tool belt, and I am a convert.

I became so used to this that the first time a user used my Filament input and I saw a space after some text, I was really confused. Why did this happen?

Let me tell you how to fix this on the form itself, how to do it globally, and what that might cause a problem with.

First, let’s take a look at the middleware stack inside of Laravel 13. I just want to review one piece. It’s configured in Middleware::getGlobalMiddleware() in the Laravel project itself.

public function getGlobalMiddleware()
{
  $middleware = $this->global ?: array_values(array_filter([
    \Illuminate\Http\Middleware\ValidatePathEncoding::class,
    \Illuminate\Foundation\Http\Middleware\InvokeDeferredCallbacks::class,
    $this->trustHosts ? \Illuminate\Http\Middleware\TrustHosts::class : null,
    \Illuminate\Http\Middleware\TrustProxies::class,
    \Illuminate\Http\Middleware\HandleCors::class,
    \Illuminate\Foundation\Http\Middleware\PreventRequestsDuringMaintenance::class,
    \Illuminate\Http\Middleware\ValidatePostSize::class,
    \Illuminate\Foundation\Http\Middleware\TrimStrings::class,
    \Illuminate\Foundation\Http\Middleware\ConvertEmptyStringsToNull::class,
  ]));
}

php

TrimStrings is being registered for everything. (As a reminder, you can customize - or remove - your TrimStrings in the bootstrap/app.php file.)

This is disabled in Filament (because of Livewire) - it turns off that middleware for its requests. There are obvious reasons for this - but that’s beyond the scope of this entry.

The point is, you have to write it on individual fields yourself.

Let’s see what a name field might look like before.

return $schema
  ->components([
    TextInput::make('name')
      ->required()
      ->maxLength(255),
  ]);

php

Very simply, this just takes the name, validates the length, and saves it to the record.

Sending in aaron results in aaron as the saved data. Send in aaron and now the saved data is aaron .

Solving String Trimming on a Single Filament Field

We can solve this on the field itself by just adding the trim() method.

return $schema
  ->components([
    TextInput::make('name')
      ->required()
      ->trim()
      ->maxLength(255),
  ]);

php

Now, the data is trimmed before it is sent/saved.

This is awesome… but now I have to rely on adding this for every field.

Why would I even want to do that, though? Don’t I want this to happen to every field?

Solving String Trimming Globally for Filament

Well, there is a way to do this. We can add a global configuration in the boot method of a service provider. Like this:

use Filament\Forms\Components\TextInput;

TextInput::configureUsing(function (TextInput $textInput): void {
  $textInput
    ->dehydrateStateUsing(function (?string $state): ?string {
      return is_string($state) ? trim($state) : $state;
    });
});

php

Simply, this adds a dehydrateStateUsing callback to all TextInput fields. If it’s a string, it trims it and returns - otherwise just sends it back.

Perfect, tested and it trims them all.

One Caveat for This Solution

There is one thing I have to remind you of, though. Since you register this here, it’s the dehydrateStateUsing callback for all TextInput fields. If you need to customize your own, you will define that on the field itself. Don’t forget to call ->trim() yourself then - as there is only one callback, not a stack.