Symfony: internal forwarding vs render controller - symfony

I have simple action in simple controller:
public function _targetAction(RequestStack $requestStack)
{
$request = $requestStack->getMasterRequest();
// ...
}
And two ways to call it. First:
// The same or other controller
public function topAction(Request $request)
{
// forward to SimpleController:_target
return $this->forward('AppBundle:Simple:_target');
}
Second from twig (subrequest):
// SimpleController
public function topAction(Request $request)
{
// render
return $this->render('AppBundle:Simple:top.html.twig');
}
// top.html.twig
{{ render(controller('AppBundle:Simple:_target')) }}
How can i idenitfy which way i get to the SimpleController::_targetAction in this method:
public function _targetAction(RequestStack $requestStack)
{
// what can i do here to uniquely identify current way
// Note: $requestStack->getParentRequest() is not null in both cases
}

In my opinion, if you need to execute different code depending on the call type, you should considere create separate routes for each action.
In case you really want to use the same, my best shot is to add a parameter on the route to identify the request.
/**
*
* #Route("/target/{from}", name="_target")
*/
public function _targetAction($from)
{
if($from == 'view'){
// execute code for view call
} else {
// execute code for controller call
}
}
And then, when you call it, pass a different parameter depending on caller type:
TWIG
{{ render(controller('AppBundle:Simple:_target', { 'from': 'view' })) }}
CONTROLLER
return $this->forward('_target', array('from' => 'controller'));

Related

Prevent the doctrine postLoad event for some cases

I have an entity BlogPost with a status property. This status property depends on an external API call which is handled via the doctrine postLoad event. All other properties are stored in the local database.
public function postLoad(BlogPost $post)
{
$this->postHandler->calculateStatus($post);
}
The problem is, in some cases i don't want to calculate the status at all. For example if i want to get only the description of all blogposts.
With the code above, all blog entities being loaded will trigger the postLoad event even if i just want to have values from a local database. That is very expensive and not acceptable.
So for example in my repository class i want to get all BlogPosts having a website without invoking the postLoad event.
public function findBlogPosts()
{
$qb = $this->getEntityManager()->createQueryBuilder();
$qb->select('bp')
->from('AppBundle:BlogPosts', 'bp')
->innerJoin('bp.website', 'w');
return $qb->getQuery()->getResult();
}
Is there a way to say "Yes, load the BlogPost collection, but do not fire event!" ???
Any other approaches? Custom event?
Thanks
Why don't just move this logic outside the post entity and event listener? If you know when you need to calculate the status you can do it explicitly.
For example
$post = $this->entityManager->find(BlogPost::class, $postId);
$status = $this->postHandler->calculateStatus($post);
The other approach I could suggest is not good but works. You could use lazy calculation and instead of calling $this->postHandler->calculateStatus($this) in postLoad event listener you could inject postHandler service into entity and perform the calculation in the moment you actually need it.
For example if you need calculation when calling $blogPost->getStatus() method, you could do it this way:
interface PostHandlerAwareInterface
{
public function setPostHandler(PostHandlerInterface $postHandler): void;
}
class EntityServiceInjectorEventSubscriber implements EventSubscriber
{
/** #var PostHandlerInterface */
private $postHandler;
public function postLoad($entity): void
{
$this->injectServices($entity);
}
public function postPersist($entity): void
{
$this->injectServices($entity);
}
private function injectServices($entity): void
{
if ($entity instanceof PostHandlerAwareInterface) {
$entity->setPostHandler($this->postHandler);
}
}
}
class BlogPost extends PostHandlerAwareInterface
{
/** #var PostHandlerInterface */
private $postHandler;
private $status;
public function setPostHandler(PostHandlerInterface $postHandler): void
{
$this->postHandler = $postHandler;
}
public function getStatus()
{
if (null === $this->status) {
$this->postHandler->calculateStatus($this);
}
return $this->status;
}
}
If you don't like this idea you still could manage it via (BUT I STRONGLY DO NOT RECOMMEND DO THIS DIRTY HACK) setting the flag to your entity event listener.
You could inject your entity event listener to the code and set flag before fetching data:
class BlogPostCalculateStatusListener
{
/** #var bool */
private $calculationEnabled = true;
public function suspendCalculation(): void
{
$this->calculationEnabled = false;
}
public function resumeCalculation(): void
{
$this->calculationEnabled = true;
}
public function postLoad(BlogPost $post): void
{
if ($this->calculationEnabled) {
$this->postHandler->calculateStatus($post);
}
}
}
$this->calculateStatusListener->suspendCalculation();
$blogPosts = $blogPostRepository->findBlogPosts();
$this->calculateStatusListener->resumeCalculation();
Hope this helps.
PS. If you want to get only the descriptions of all blog posts you can do this way:
class BlogPostRepository
{
public function findBlogPosts()
{
$qb = $this->getEntityManager()->createQueryBuilder();
$qb->select('bp.description')
->from('AppBundle:BlogPosts', 'bp')
->innerJoin('bp.website', 'w');
return $qb->getQuery()->getArrayResult();
}
}
getArrayResult does not invoke lifecycle callbacks.
Since i haven't found a real similar use case on the internet, i'll go for the following solution which seems the easiest and most acceptable cleanest to me. Maybe someone else could find this useful.
Implement a TransientLoadable Interface
interface TransientLoadable
{
public function isLoaded() : bool;
public function setLoaded(bool $loaded) : TransientLoadable;
public function setTransientLoadingFunction(\Closure $loadingFunction) :
TransientLoadable;
}
Implement the entity
class BlogPost implements TransientLoadable
{
...
}
Setup Loading function on postLoad Event
public function postLoad(BlogPost $post)
{
$func = function() use ($postHandler, $post)
{
//Since there may be another fields being loaded from the same API, catch them also since data is anyway in the same request
$postHandler->setAllDataFromAPI($post)
//Set the loading state to true to prevent calling the API again for the next property which may also be transient
$post->setLoaded(true);
}
$post->setTransientLoadingFunction($func)
}
Use the built-in lazy loading mechanism to get the property from the API only when it's needed
class BlogPost implements TransientLoadable
{
private function getStatus() : int
{
if (!$this->isLoaded) {
call_user_function($this->loadingFunction)
}
return $this->status;
}
private function getVisitorCount() : int
{
if (!$this->isLoaded) {
call_user_function($this->loadingFunction)
}
return $this->visitorCount;
}
}
So what's happening? Let's imagine we want to get the status and the visitor count, both are loaded via a single external API call.
If some api-dependent property of the entity is needed, all other properties gets loaded too (since we don't want to have for each property another call). This in ensured through the loaded function of the TransientLoadable interface. All data gets loaded by the setAllDataFromAPI function which is injected as a closure function.
I think that is not the cleanest solution. The loading stuf should be done by an extra layer on top of the entity class. Since sonata admin does not deal with such an layer, i think that this solution is cleaner than writing the loading mechanism directly to the entity class.
I am open to another suggestions or feedback
Thanks

Use several times global parameter in controller symfony

I need your help in Symfony controller, there is a way to use a global parameter and get the different value in different method.
Actually I have this.
class ArticleController extends Controller
{
//Injection of white october bundle
/** #DI\Inject("white_october_breadcrumbs") */
private $wob;
public function indexAction(Request $request)
{
$this->wob->addRouteItem("Article", "article_index");
//Some stuff
}
public function addAction(Request $request, $id=0)
{
if($request->get('_route') === "article_add"){
$this->wob->addRouteItem("Add article", "article_add");
} else {
$this->wob->addRouteItem("Edit article", "article_edit");
}
//Some stuff
}
//Other functions..
}
As you can see, actually my breadcrumb only keep the last value of the global parameter $wob
Example :
Home > Article
Home > Edit article
But i want :
Home > Article > Edit article
Don't know if it's possible
Thank you in advance !
Your addAction is completely separated from indexAction and these are different requests, so you cannot expect to keep value of $wob property between requests.
In yours example you can make parent only inside the same action:
public function addAction(Request $request, $id=0)
{
$this->wob->addRouteItem("Article", "article_index");
if($request->get('_route') === "article_add"){
$this->wob->addRouteItem("Add article", "article_add");
} else {
$this->wob->addRouteItem("Edit article", "article_edit");
}
//Some stuff
}

How return an array from a symfony2 controller action?

in my symfony2 project i need call the same action in many controllers and this action should return a very simple php array that then will be passed to a twig template by these controllers. How can i do it?
A pratical example can explain my situation better.
1.shared controller
// Acme/DemoBundle/Controller/MetasController
class MetasController extends Controller {
public function metasAction() {
$myArray= array();
return $myAarray;
}
}
page render controller
// Acme/DemoBundle/Controller/PageController
class PageController extends Controller {
protected $property = "test";
public function indexAction() {
$metas= $this->forward('AcmeDemoBundle:Metas:metas');
return $this->render('AcmeDemoBundle:Page:index.html.twig', array('property'=>property, 'metas'=>$metas));
}
}
when i do this i get an error: the controller must be a response array given.
You should create a service
// Acme/DemoBundle/Controller/MetasController
class MetasController {
public function metasAction() {
$myArray= array();
return $myAarray;
}
}
declare as service in Acme\DemoBundle\Resources\config\services.yml
services:
demo.metas:
class: "Acme\DemoBundle\Controller\MetasController"
Then you can use it in any other controller
// Acme/DemoBundle/Controller/PageController
class PageController extends Controller {
protected $property = "test";
public function indexAction() {
$metas= $this->get('demo.metas')->metas();
return $this->render('AcmeDemoBundle:Page:index.html.twig', array('property'=>property, 'metas'=>$metas));
}
}
In your action controller :
<?php
...
$arrayExample = array();
return $this->render('ExampleBundle:ExampleFolder:exampleTemplate', array('myArray' => $arrayExample));
And in your twig template now you have access to your array using myArray
Example :
{% for data in myArray %}
...
{% endfor %}
Try this :
use Symfony\Component\HttpFoundation\Response;
public function indexAction()
{
...
$content = $this->renderView(
'AcmeDemoBundle:Page:index.html.twig',
array('property'=> $property,
'metas' => $metas
));
return new Response($content);
}
Yes, you can register your controller as a service as it said above but I would recommend to isolate this logic in a different place. It might be a service but not controller.
As I understand you need the same array in several places. So, it might be some class registered as service or some simple class with static method providing this array. In this case your code will be much cleaner.
If you need this array only in view you can define custom twig method which will return array you need. If this array might be different time to time (if it might depend on some data) you can pass entity manager to the service providing this array or to the twig extension.
(The best use of controllers is to be just a proxy between view and data layer. It's not a good idea to use it for such purposes as you described (in my opinion of course).)

filter boolean variable in a twig template

I have a boolean variable(0, 1) in my database and I want to filter it to a word 0 for 'NO', and 1 for 'Yes'. how can I do that in a twig template
I want something like {{ bool_var | '??' }} where the '??' is the filter
Quick way to achieve that is to use the ternary operator:
{{ bool_var ? 'Yes':'No' }}
http://twig.sensiolabs.org/doc/templates.html#other-operators
You could also create a custom filter that would do this. Read about custom TWIG extensions - http://symfony.com/doc/current/cookbook/templating/twig_extension.html
To build on what #dmnptr said in his last paragraph, in your app bundle, create a /Twig folder and create an AppExtension class inside.
class AppExtension extends \Twig_Extension
{
public function getFilters()
{
return array(
new \Twig_SimpleFilter('boolean', array($this, 'booleanFilter')),
);
}
public function booleanFilter($value)
{
if ($value) {
return "Yes";
} else {
return "No";
}
}
public function getName()
{
return 'app_extension';
}
}
Then, in your bundle's Resources/config/ folder, add the following to your services.yml where class is the class of the new class:
app.twig_extension:
class: [YourAppBundleNamespace]\Twig\AppExtension
public: false
tags:
- { name: twig.extension }
The filter will be available in Twig by simply appending a |boolean to any variable.
Or even better you could make a boolean to string transformer and add it to your form.
It might be 'more' code but the upside is reusability. You wouldn't have to make your templates dirty with logic and you could reuse it to all the forms you want :)
Pros:
Not tied to the form component so you can still use it.
Use it anywhere, more functionality than a twig extension.
No need to mess with twig or symfony configuration.
Can use it in forms themselves.
Documentation:
http://symfony.com/doc/current/cookbook/form/data_transformers.html
Example from:
Symfony2 Forms BooleanToStringTransformer Issue
<?php
use Symfony\Component\Form\DataTransformerInterface;
use Symfony\Component\Form\Exception\TransformationFailedException;
class BooleanToStringTransformer implements DataTransformerInterface
{
private $trueValue;
private $falseValue;
public function __construct($trueValue, $falseValue)
{
$this->trueValue = $trueValue;
$this->falseValue = $falseValue;
}
public function transform($value)
{
if (null === $value) {
return null;
}
if (!is_bool($value)) {
throw new TransformationFailedException('Expected a Boolean.');
}
return true === $value ? $this->trueValue : $this->falseValue;
}
public function reverseTransform($value)
{
if (null === $value) {
return null;
}
if (!is_string($value)) {
throw new TransformationFailedException('Expected a string.');
}
return $this->trueValue === $value;
}
}

Nearly completed - just need to finish Twig extension to render ESI - Symfony2

I want to create a Twig extension and use this:
{{ new_func(route-name) }}
To do the same thing as:
{{ render_esi(url(route-name)) }}
...but with some adjustments
It's nearly done but it's this line that needs to be changed, but I can't see how I can call an ESI from this code (outside of Twig):
return $environment->render($route); /// needs to receive route and render an ESI
-
namespace Acme\Bundle\MyBundle\Twig;
class NewTwigFunction extends \Twig_Extension
{
private $request;
public function __construct($container)
{
$this->request = $container->get('request');
}
public function getFunctions() {
return array(
'new_func' => new \Twig_Function_Method($this, 'newFunction', array('needs_environment' => true) )
);
}
public function newFunction(\Twig_Environment $environment, $route) {
$r = $this->request;
return $environment->render($route);
}
public function getName() {
return "new_func";
}
}
I'm not sure I follow why would you need this, but I think it's great as an example of an abstract question:
How do I track down & extend core functionality of Symfony2?
Finding the functionality
Seems that you're having trouble finding where is this render_esi executed, so let's tackle that!
This doesn't seem like a standard Twig feature, so it must be an extension, just like the one you're creating.
It should be located somewhere in Symfony2 core files, so we start looking into vendor/symfony/src folder. Since we already know that we're dealing with an extension of Twig, Component folder is out of the question (because Twig is a separate library from Symfony2 core components).
So we've narrowed it down to Bridge and Bundle. If we look inside them then we see Bundle/TwigBundle or Bridge/Twig. We also know that Symfony2 developers follow a strict code/architecture style, so we know exactly which folder to look for - Extension. Now it's just a matter of checking them both.
Long story short we find what we're looking for in vendor/symfony/src/Symfony/Bridge/Twig/Extension/HttpKernelExtension, where we see a render_* function. Jackpot!
Extending the functionality
Before changing anything, we need to first emulate what's already there, so we create something like this:
use Symfony\Component\HttpKernel\Fragment\FragmentHandler;
class NewTwigFunction extends \Twig_Extension
{
private $handler;
public function __construct(FragmentHandler $handler)
{
$this->handler = $handler;
}
public function getFunctions()
{
return array(
'new_func' => new \Twig_Function_Method($this, 'newFunction', array('is_safe' => array('html')) )
);
}
public function newFunction($uri, $options = array())
{
return $this->handler->render($uri, 'esi', $options);
}
public function getName()
{
return "new_func";
}
}
Now when you call
{{ new_func(url(route-name)) }}
you should see same results as
{{ render_esi(url(route-name)) }}
But we still need to get rid of the url part.
Easy as pie, we just add the router service to our extension! Now our extension could look like this:
use Symfony\Component\Routing\Router;
use Symfony\Component\HttpKernel\Fragment\FragmentHandler;
class NewTwigFunction extends \Twig_Extension
{
private $handler;
private $router;
public function __construct(FragmentHandler $handler, Router $router)
{
$this->handler = $handler;
$this->router = $router;
}
public function getFunctions()
{
return array(
'new_func' => new \Twig_Function_Method($this, 'newFunction', array('is_safe' => array('html')) )
);
}
public function newFunction($routeName, $options = array())
{
$uri = $this->router->generate($routeName);
return $this->handler->render($uri, 'esi', $options);
}
public function getName()
{
return "new_func";
}
}
and {{ new_func(route-name) }} should work as expected.
Hooking in-between
The way I understood it, you want almost the same functionality as render_esi, but with slight changes to output.
So that means that we need to hook somewhere in-between return and $this->handler->render($uri, $strategy, $options);.
How deep down the rabbit hole we need to go depends on the change.
For example, if you want to alter Response object before it's turned into actual html string, you need to find the spot where it's turned in the first place. A good bet would be to look into FragmentHandler:
protected function deliver(Response $response)
{
if (!$response->isSuccessful()) {
throw new \RuntimeException(sprintf('Error when rendering "%s" (Status code is %s).', $this->request->getUri(), $response->getStatusCode()));
}
if (!$response instanceof StreamedResponse) {
return $response->getContent();
}
$response->sendContent();
}
Got it! Now you just need to extend FragmentHandler::deliver() and pass your implementation of it into your twig extenion.
Tracking down configuration
You have to understand that Symfony2 core code is not that different from what you write in your everyday life, it still abides by its own rules.
For example, when normally creating a Twig extension in Symfony2 you need to configure it as a service, right? Well, Symfony2 core extensions are configured in the same way. You just need to find where the configuration files are located.
Following the logic from Extending the functionality we know for sure that they're not located in Component. Bridge is actually a name for a design pattern - not a place where you'd place your service configuration :)
So we're left with Bundle - and obviously that's where we find all the information we need: vendor/symfony/src/Bundle/TwigBundle/Resources/config/twig.xml
Now we simply look up how original HttpKernelExtension is configured and follow its lead:
<service id="twig.extension.httpkernel" class="%twig.extension.httpkernel.class%" public="false">
<argument type="service" id="fragment.handler" />
</service>
Transforming it into a more commonly used .yml format, our extension config could look like this:
new_func:
class: Acme\Bundle\MyBundle\Twig\NewTwigFunction
arguments:
- "#fragment.handler"
# Uncomment when implementing code from 2nd example
# - "#router"
tags:
- { name: twig.extension }
public: false

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