Laravel Helper Function to create a Unique slug based on Provided Model Instance. Save 'slugify_model.php' in your 'app/Helpers/' directory and update your composer.json to reference and autoload the helper function.

composer.json

{
    ...
    "autoload": {
        "psr-4": {
            "App\\": "app/",
            "Database\\Factories\\": "database/factories/",
            "Database\\Seeders\\": "database/seeders/"
        },
        "files": [
            ...
            "app/Helpers/slugify_model.php",
            ...
        ]
    },
    ...
}

examples.php

<?php

/* Usage Example: Post */

$validated = $request->validated();

// Creating a New Model
$validated['slug'] = slugify_model(Post::class, $validated['title']);
// return: this-is-an-example-of-slugify
// if slug already exists: this-is-an-example-of-slugify-9rkt6

Post::create($validated);


// Updating a Model
$validated['slug'] = slugify_model(
                        model: Post::class,
                        columnOrTitle: $validated['title'],
                        ignore: $post->slug
                    );
// return: this-is-an-updated-example-of-slugify
// if slug already exists: this-is-an-updated-example-of-slugify-jToVK
$post->update($validated);



// On-the-fly Slugify :P

// 1. Here, 'title' Column in 'posts' table will be slugified
// and 'slug' column will be used to verify if it exists.
$slug = slugify_model($post, 'title');
// return: on-the-fly-slugify

// 2. Here, custom slug column is used to verify if it exists.
$slug = slugify_model($post, 'title', slugColumn: 'shortname');
// return: on-the-fly-slugify

// 3. Ignoring a Slug when ClassName::class is provided as first param
$slug = slugify_model(Post::class, $validated['title'], $post->slug);

slugify_model.php

<?php

use Illuminate\Database\Eloquent\Model;

if (! function_exists('slugify_model')) {

    /**
     * Creates a URL Friendly Unique Slug (also ignore if necessary) 
     * It will also verify if it already exists, & if it does, append Str::random()
     * Example: this-is-a-friendly-slug
     * OR Example: this-is-a-friendly-slug-9rkt6
     * 
     * @param \Illuminate\Database\Eloquent\Model|string $model
     * @param string|null $columnOrTitle Database Column for "title" or Title to Slugify
     * @param string|null $ignore Ignore a slug for Regeneration if slug is similar
     * @param string $slugColumn column used to check for duplicates
     * @param bool $regenrate Specifies if regeneration is done
     * @return string
     */
    
    function slugify_model(
        Model|string $model,
        string $columnOrTitle,
        ?string $ignore = null,
        string $slugColumn = 'slug',
        bool $regenerate = false
    ): string
    {
        $data = ($model instanceof Model) ?
                $model->$columnOrTitle :
                $columnOrTitle;

        (!$model instanceof Model && ($columnOrTitle == null OR $columnOrTitle == '')) ?
            throw(new Exception('No Title Provided to Slugify')) : null;

        $slug = Str::slug($data);
        $ignore = ($model instanceof Model && $ignore === null) ?
                    $model->$slugColumn : $ignore;

        $slug = ($regenerate && $slug !== $ignore) ?
                $slug . '-' . Str::random(5) :
                $slug;

        $instance = ($model instanceof Model) ?
                    get_class($model) :
                    $model;

        $lookup = ($slug !== $ignore) ?
                    $instance::where($slugColumn, $slug)->first() :
                    false;

        return ($lookup) ?
                slugify_model(
                    $model,
                    $columnOrTitle,
                    $ignore,
                    $slugColumn,
                    regenerate: true
                ) : $slug;
    }
}

cool!