[5.3] Ajax component support of Stringable results

[Fedik]

Pull Request for #43471 .

Summary of Changes

Adding support of Stringable https://www.php.net/manual/en/class.stringable.php results to Ajax component.
Adding Joomla\CMS\String\StringableInterface results to Ajax component, this is transitioning interface to Stringable https://www.php.net/manual/en/class.stringable.php.
This allows to customise the response much better, than it is currently.

Testing Instructions

Add following code in to plugins/system/skipto/src/Extension/Skipto.php:

    public function onAjaxSkiptoTest1(\Joomla\CMS\Event\Plugin\AjaxEvent $event)
    {
        $event->updateEventResult(new class ('test 1') extends \Joomla\CMS\Response\JsonResponse implements \Joomla\CMS\String\StringableInterface {});
    }

    public function onAjaxSkiptoTest2(\Joomla\CMS\Event\Plugin\AjaxEvent $event)
    {
        $event->addResult(['foo', 'bar']);
    }

    public function onAjaxSkiptoTestError(\Joomla\CMS\Event\Plugin\AjaxEvent $event)
    {
        throw new \Exception('test error');
    }

Then open following links:

1. /administrator/index.php?option=com_ajax&plugin=skiptoTest1&group=system&format=raw
2. /administrator/index.php?option=com_ajax&plugin=skiptoTest1&group=system&format=json
3. /administrator/index.php?option=com_ajax&plugin=skiptoTest2&group=system&format=json
4. /administrator/index.php?option=com_ajax&plugin=skiptoTestError&group=system&format=raw
5. /administrator/index.php?option=com_ajax&plugin=skiptoTestError&group=system&format=json

Expected result AFTER applying this Pull Request

Check response for each:

1. {"success":true,"message":null,"messages":null,"data":"test 1"}
2. {"success":true,"message":null,"messages":null,"data":"test 1"}
3. {"success":true,"message":null,"messages":null,"data":[["foo","bar"]]}
4. Exception: test error
5. {"success":false,"message":"test error","messages":null,"data":null}

Link to documentations

Please select:

• Documentation link for docs.joomla.org:
• No documentation changes for docs.joomla.org needed
• Pull Request link for manual.joomla.org: com_ajax Stringable interface Manual#274
• No documentation changes for manual.joomla.org needed

[korenevskiy]

Thanks, I tested it. I spent many hours testing on my project.
It can be seen that you spent just as many hours writing, testing, finding bugs and writing documentation for PR.
I tested in JSON format, with error, without error, with data and with a JsonResponse object. I also set the parameters
$input->set('ignoreMessages',false, 'bool'), and also tested in RAW mode, also in different configurations.
I also made an error throw with a message.
Now Joomla has become better. Now we can send customized messages as system messages in case of an error, and special notifications. Respect.

there were no problems during testing.

[Fedik]

@korenevskiy Please visit https://issues.joomla.org/tracker/joomla-cms/43530 and push the button, thanks

[carlitorweb]

/administrator/index.php?option=com_ajax&plugin=skiptoTest2&group=system&format=raw

Warning: Array to string conversion in [ROOT]\components\com_ajax\ajax.php on line 238

[Fedik]

@carlitorweb that is correct, you cannot run skiptoTest2 with format=raw, only with format=json. As in my instruction.
Because format=raw cannot handle anything else than scalar or stringable objects, and skiptoTest2 produces an array.

[carlitorweb]

I have tested this item ✅ successfully on 66f35b7

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[korenevskiy]

I have tested this item ✅ successfully on 66f35b7

there were no problems during testing.

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[Quy]

RTC

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[rdeutz]

We discussed this last week and we think this is a b/c break. It would be better to add a new format instead of changing an existing one and do "kind of magic" on this.

[korenevskiy]

We discussed this last week and we think this is a b/c break. It would be better to add a new format instead of changing an existing one and do "kind of magic" on this.

By creating a new format, we force each developer to refer to the documentation each time in order to understand the subtleties of the differences between each format. But ultimately the formats are the same, it's just a matter of processing JSON.

[Fedik]

p

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[Fedik]

which means backward compatibility is quite simple

Nope, when existing extension provides result as JsonResponse, then it will be wrapped in to another JsonResponse. So in result we will have:
new JsonResponse($anotherJsonResponse) will produce : {"data":{"data":{ ... the object properties}}}.

Even if it does not make sense, it still changing the response that com_ajax will send. and that will break that extension.

[korenevskiy]

new JsonResponse($anotherJsonResponse) will produce : {"data":{"data":{ ... the object properties}}}.

if (!($results instanceof Throwable) && $results instanceof Stringable)

At the same time, it is necessary to add to the \JSONResponsee class
libraries/src/Response/JsonResponse.php

class JsonResponse implements  Stringable{
}

If you do as you say, parents should do this interface for \JSONResponse.

[korenevskiy]

I like your idea, but it seems to me that it is possible to achieve an elegant solution without adding a new interface.

[korenevskiy]

OR

if (!($results instanceof Throwable) && $results instanceof StringableResponseInterface)

At the same time, it is necessary to add to the \JSONResponsee class
libraries/src/Response/JsonResponse.php

class JsonResponse implements  StringableResponseInterface{
}

Where StringableResponseInterface it is joomla new interface

[Fedik]

No, JsonResponse already implements Stringable implicitly.

Unlike most interfaces, Stringable is implicitly present on any class that has the magic __toString() method defined

And currently we cannot add our StringableInterface to it, because it will change response format. In reasons I wrote earlier.

Currently developers who wants a custom response should implement StringableInterface on their own. And in future (~joomla 7), we change com_ajax to use PHP native Stringable, and all will continue to work without breaks.

[korenevskiy]

You right
Maybe?

if (!($results instanceof Throwable) 
&& ($results instanceof \Joomla\CMS\Response\JsonResponse || \StringableResponseInterface))

Where StringableResponseInterface it is joomla new interface

[korenevskiy]

Is it worth checking the object for JsonSerializable interface?

https://www.php.net/manual/en/jsonserializable.jsonserialize.php

[Fedik]

That a bit diferent approach, but could work in some cases also.

[korenevskiy]

Why is this method bad?
#43530 (comment)

[Fedik]

Because as for now it behaviors as "double wrapping", changing it will be b/c break.
#43530 (comment)

[korenevskiy]

if (!($results instanceof Throwable) 
&& ($results instanceof \Joomla\CMS\Response\JsonResponse || \StringableResponseInterface)){
	echo $results;
}else{
	echo new JsonResponse($results, null, false, $input->get('ignoreMessages', true, 'bool'));
}

Where StringableResponseInterface it is joomla new interface

But where is the double explosion here?, because if the object is JsonResponse, then there is no "double wrapping". In this case, the conversion to the string type occurs.

[Fedik]

because if the object is JsonResponse, then there is no "double wrapping"

"will be".
But current behavior (in j3, j4, j5) is diferent

[korenevskiy]

The previous behavior caused a nested object of class \JsonResponse to be created in a new amendment object of class \JsonResponse , now this object class \JsonResponse will be cast to string .
Do you think there are people who returned the \JsonResponse object from the extension, which was re-serialized in the \JsonResponse object? If there are any, it will cause an error.
Well, then there is no solution.
Because the right decision will cause an error or misunderstanding.
Then let's assign this amendment to Joomla 6. Where it will be explicitly stated that nested \JsonResponse should not be in each other.

[Fedik]

That what this PR is doing.
You already can use it with #43530 (comment) (when the PR will be merged). Then your code will continue to work in j7, without changes.

[korenevskiy]

I know for sure that the interface name should indicate that the new interface was created to respond to the request.
There will be confusion in assigning the interface name, people will mistakenly inherit from the wrong interface, or for backward compatibility, you will have to store this file for a long time.
StringableResponseInterface

[Fedik]

The full name Joomla\CMS\String\StringableInterface, so it is fine

[korenevskiy]

What value will this interface have other than the Ajax class of the component?

[exlemor]

I have tested this item ✅ successfully on 4ea1349

I have tested this successfully. ( Thanks to @LadySolveig for making sure I didn't kill another test server ;) lol )

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[HLeithner]

This pull request has been automatically rebased to 5.3-dev.

[fgsw]

I have tested this item ✅ successfully on 4ea1349

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[alikon]

rtc

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