php - Laravel 5 how to set Cache-Control HTTP header globally?

Question

My Laravel application is returning Cache-Control: no-cache, private HTTP header by default for each site. How can I change this behaviour?

P.S.: It is not a PHP.ini problem, because changing session.cache_limiter to empty/public does not change anything.

Answer 1

Laravel 5.6+

There's no longer any need to add your own custom middleware.

The SetCacheHeaders middleware comes out of the box with Laravel, aliased as cache.headers

The nice thing about this Middleware is that it only applies to GET and HEAD requests - it will not cache POST or PUT requests since you almost never want to do that.

You can apply this globally easily by updating your RouteServiceProvider:

protected function mapWebRoutes()
{
    Route::middleware('web')
        ->middleware('cache.headers:private;max_age=3600') // added this line
        ->namespace($this->namespace)
        ->group(base_path('routes/web.php'));
}

protected function mapApiRoutes()
{
    Route::prefix('api')
        ->middleware('api')
        ->middleware('cache.headers:private;max_age=3600') // added this line
        ->namespace($this->namespace)
        ->group(base_path('routes/api.php'));
}

I don't recommend that though. Instead, as with any middleware, you can easily apply to specific endpoints, groups, or within the controller itself, e.g.:

Route::middleware('cache.headers:private;max_age=3600')->group(function() {
    Route::get('cache-for-an-hour', 'MyController@cachedMethod');
    Route::get('another-route', 'MyController@alsoCached');
    Route::get('third-route', 'MyController@alsoAlsoCached');
});

Note that the options are separated by semicolon not comma, and hyphens are replaced by underscores. Also, Symfony only supports a limited number of options:

'etag', 'last_modified', 'max_age', 's_maxage', 'private', 'public', 'immutable'

In other words you can't simply copy and paste a standard Cache-Control header value, you will need to update the formatting:

CacheControl format:       private, no-cache, max-age=3600
  ->
Laravel/Symfony format:    private;max_age=3600