Add support for rendering flash messages in templates

[gabiudrescu]

I have added flash notification in templates. looks like this for me:

in code, I generate them like this:

class AdminController extends BaseAdminController
{
    public function extendAction()
    {
        $em = $this->getDoctrine()->getManager();
        $repository = $this->getDoctrine()->getRepository("GabiUJobeetBundle:Job");

        $id = $this->request->query->get('id');

        $entity = $repository->find($id);
        $entity->extend();

        $em->persist($entity);
        $em->flush();

        $this->addFlash("success", "Entity updated");

        return $this->redirectToRoute('admin', array(
            "view" => 'edit',
            "entity" => $this->request->query->get('entity')
        ));
    }
}

[javiereguiluz]

@gabiudrescu thanks for proposing this change. To be honest, I prefer to not add this feature. Why? Because I believe notifications should be made when things go wrong, not when things worked (which by the way, it's 99.99% of the times). If you take a look at well-designed desktop applications, they never notify you when things go right.

[Pierstoval]

I'm also 👎 for this feature, even if it's well implemented. But we should provide a small cookbook when customers want this kind of feature in backends "we" develop.

[javiereguiluz]

@Pierstoval yes, that's why I haven't closed this issue. I don't want it in the default bundle ... but I want to make it easy to use it for people who really want that feature.

[gabiudrescu]

hi Javier,

the PHP code above is my own code, in my own bundle. The pull request is about the ability of rendering any kind of notifications.

for example:

[Pierstoval]

@gabiudrescu I think we totally got it but actually these notifications depend on an app-specific issue.
I have more than 5 projects using EasyAdmin, and none of them need any notification like these. It's subjective, of course, but it's actually a 100% non-use for this behavior.

But as you did in this PR, implementing it is really really easy, so it's not a problem.

[gabiudrescu]

yeah, indeed, the code should have hinted me it's self explanatory. anyway, thanks for your feedback.

I'd be curious - how do you notify users in case something bad happens?

[Pierstoval]

If something bad happens, it should throw an exception (it's the best practice) so they're handled by EasyAdmin IIRC.

[javiereguiluz]

Yes. When some error happens, we throw an exception to display a proper error page. Of course we still need to add more error pages, but we've already covered some of the biggest problems: https://github.com/javiereguiluz/EasyAdminBundle/tree/master/Exception

[gabiudrescu]

thanks everyone for the feedback. I'd like to use my modifications in this pull request in an application I'm currently developing. any tips and tricks about how I can automatically do that and still follow the master branch development (when there's any new addition)?

[Pierstoval]

Just override the layouts with the EasyAdmin override system, extend the original layouts, and customize the part you need:

{% block content_header %}
    {{ include('easy_admin/custom_notification_template.html.twig') }}
    {{ parent() }}
{% endblock %}

[javiereguiluz]

@gabiudrescu I'm finishing this feature in #430. That's why I'm closing this pull request. Obviously I've reused your original commit, so you'll get full credit for your work. Thanks!

[gabiudrescu]

whohoo, that's good news 👍 though your modifications in feature #430 have a much cleaner implementaton, I'm glad my idea has been useful for such an awesome bundle.

keep up the good work!