拡張子.html等､バニラPHPで作られたサイトのURLを維持してLaravelでリニューアルする

Route::get('/company/', function () {
    return view('web.company.index');
})->name('company.index');


Route::get('/company/sub/', function () {
    return view('web.company.sub.index');
})->name('company.sub.index');

Route::get('/company/history.htm', function () {
    return view('web.company.history');
})->name('company.history');

Route::get('products/{hoge}/{id}', [ProductController::class, 'detail'])
    ->name('products.detail')->where([
        'hoge' => '[a-z]{3,9}',
        'id' => '[1-9][0-9]{0,3}',
    ])->name('products.detail);

  <ul>
    <li><a href="/company/">HTMLで指定</a></li>
    <li><a href="{{ route('company.index') }}">route()で指定</a></li>
    <li><a href="{{ url('/company/') }}">url()で指定</a></li>
  </ul>

<ul>
  <li><a href="/company/">HTMLで指定</a></li>
  <li><a href="http://example.jp/company">route()で指定</a></li>
  <li><a href="http://example.jp/company">url()で指定</a></li>
</ul>

<IfModule mod_rewrite.c>
    <IfModule mod_negotiation.c>
        Options -MultiViews -Indexes
    </IfModule>

    RewriteEngine On

    # Handle Authorization Header
    RewriteCond %{HTTP:Authorization} .
    RewriteRule .* - [E=HTTP_AUTHORIZATION:%{HTTP:Authorization}]

    # Redirect Trailing Slashes If Not A Folder...
    # RewriteCond %{REQUEST_FILENAME} !-d
    # RewriteCond %{REQUEST_URI} (.+)/$
    # RewriteRule ^ %1 [L,R=301]

    # Send Requests To Front Controller...
    RewriteCond %{REQUEST_FILENAME} !-d
    RewriteCond %{REQUEST_FILENAME} !-f
    RewriteRule ^ index.php [L]
</IfModule>

function route_with_slash($name, $parameters = [], $absolute = true)
{
    // Laravelのroute()関数でURLを生成
    $url = route($name, $parameters, $absolute);

    // 末尾にスラッシュがなければ追加
    if (substr($url, -1) !== '/') {
        return $url . '/';
    }
    return $url;
}

<a href="{{ route_with_slash('company.index') }}">route()で呼び出し</a>

<?php

namespace App\Routing;

use Illuminate\Routing\UrlGenerator as BaseUrlGenerator;

class UrlGenerator extends BaseUrlGenerator
{
    /**
     * Format the given URL segments into a single URL.
     *
     * @param  string  $root
     * @param  string  $path
     * @param  \Illuminate\Routing\Route|null  $route
     * @return string
     */
    public function format($root, $path, $route = null)
    {
        // 呼び出されたURLを標準の方法でフォーマット
        $url = parent::format($root, $path, $route);

        // 末尾が特定の拡張子（.htm, .html, .jpg, .png など）で終わる場合はスラッシュを追加しない
        if ($this->isFile($url)) {
            return $url;
        }

        // 末尾にスラッシュがなければ追加
        if (!empty($path) && substr($url, -1) !== '/') {
            return $url . '/';
        }

        return $url;
    }

    /**
     * Check if the URL appears to be a file (based on extension).
     *
     * @param  string  $url
     * @return bool
     */
    protected function isFile($url)
    {
        // 対象となるファイル拡張子のパターン
        $extensions = ['htm', 'html', 'jpg', 'jpeg', 'png', 'gif', 'pdf', 'css', 'js'];

        // URLが特定の拡張子で終わっているかどうかをチェック
        $pattern = '/\.(' . implode('|', $extensions) . ')$/i';

        return preg_match($pattern, $url);
    }
}

<?php

namespace App\Providers;

use Illuminate\Support\ServiceProvider;
use Illuminate\Support\Facades\Blade;
use Illuminate\Support\Facades\View;
use Illuminate\Support\Facades\Cache;
use Illuminate\Pagination\Paginator;

// 追加
use App\Routing\UrlGenerator;

class AppServiceProvider extends ServiceProvider
{
    /**
     * Register any application services.
     */
    public function register(): void
    {
        // ここでカスタムUrlGeneratorをバインド
        $this->app->singleton('url', function ($app) {
            $routes = $app['router']->getRoutes();
            $request = $app->rebinding('request', function ($app, $request) {
                $app['url']->setRequest($request);
            });

            return new UrlGenerator($routes, $request, $app['config']['app.asset_url']);
        });
    }

php artisan route:clear

RewriteRule ^company/history.htm$ /company/history [L,R=301]

 <link rel="canonical" href="http://example.jp/company/">