sort by datetime fields about data

[vjik]

Seems, problem here:

data/src/Paginator/KeysetPaginator.php

Line 309 in 55fd808

$methodName = 'get' . ucfirst($field);

For post_id method name is getPost_id.

May be we can remove magic here?

[samdark]

Removing magic is good. How would you do it?

[albertborsos]

Ok, that is an issue too, but after I update it to $methodName = 'get' . (new Inflector())->toPascalCase($field); then I will get this error:

Error: Object of class DateTimeImmutable could not be converted to string in /app/vendor/yiisoft/data/src/Paginator/KeysetPaginator.php:264
Stack trace:
#0 /app/vendor/yiisoft/data/src/Paginator/KeysetPaginator.php(176): Yiisoft\Data\Paginator\KeysetPaginator->readData(Object(Yiisoft\Yii\Cycle\Data\Reader\EntityReader), Object(Yiisoft\Data\Reader\Sort))
#1 /app/views/blog/comments/_comments.php(19): Yiisoft\Data\Paginator\KeysetPaginator->read()
#2 /app/vendor/yiisoft/view/src/PhpTemplateRenderer.php(28): require('/app/views/blog...')
#3 /app/vendor/yiisoft/view/src/PhpTemplateRenderer.php(37): Yiisoft\View\PhpTemplateRenderer->Yiisoft\View\{closure}('/app/views/blog...', Array)
#4 /app/vendor/yiisoft/view/src/ViewTrait.php(449): Yiisoft\View\PhpTemplateRenderer->render(Object(Yiisoft\View\WebView), '/app/views/blog...', Array)
#5 /app/vendor/yiisoft/view/src/ViewTrait.php(402): Yiisoft\View\WebView->renderFile('/app/views/blog...', Array)
#6 /app/views/blog/comments/index.php(25): Yiisoft\View\WebView->render('_comments', Array)
#7 /app/vendor/yiisoft/view/src/PhpTemplateRenderer.php(28): require('/app/views/blog...')
#8 /app/vendor/yiisoft/view/src/PhpTemplateRenderer.php(37): Yiisoft\View\PhpTemplateRenderer->Yiisoft\View\{closure}('/app/views/blog...', Array)
#9 /app/vendor/yiisoft/view/src/ViewTrait.php(449): Yiisoft\View\PhpTemplateRenderer->render(Object(Yiisoft\View\WebView), '/app/views/blog...', Array)
#10 /app/vendor/yiisoft/view/src/ViewTrait.php(402): Yiisoft\View\WebView->renderFile('/app/views/blog...', Array)
#11 /app/vendor/yiisoft/yii-view/src/ViewRenderer.php(322): Yiisoft\View\WebView->render('index', Array)
#12 /app/vendor/yiisoft/yii-view/src/ViewRenderer.php(119): Yiisoft\Yii\View\ViewRenderer->renderProxy('index', Array, Array, Array, Array, Array)
#13 /app/vendor/yiisoft/data-response/src/DataResponse.php(324): Yiisoft\Yii\View\ViewRenderer->Yiisoft\Yii\View\{closure}()
#14 /app/vendor/yiisoft/data-response/src/Formatter/HtmlDataResponseFormatter.php(43): Yiisoft\DataResponse\DataResponse->getData()
#15 /app/vendor/yiisoft/data-response/src/DataResponse.php(353): Yiisoft\DataResponse\Formatter\HtmlDataResponseFormatter->format(Object(Yiisoft\DataResponse\DataResponse))
#16 /app/vendor/yiisoft/data-response/src/DataResponse.php(106): Yiisoft\DataResponse\DataResponse->formatResponse()
#17 /app/vendor/yiisoft/cookies/src/CookieMiddleware.php(148): Yiisoft\DataResponse\DataResponse->getHeader('Set-Cookie')
#18 /app/vendor/yiisoft/cookies/src/CookieMiddleware.php(85): Yiisoft\Cookies\CookieMiddleware->encodeResponseSetCookieHeaders(Object(Yiisoft\DataResponse\DataResponse))
#19 /app/vendor/yiisoft/middleware-dispatcher/src/MiddlewareStack.php(104): Yiisoft\Cookies\CookieMiddleware->process(Object(HttpSoft\Message\ServerRequest), Object(Psr\Http\Server\RequestHandlerInterface@anonymous))
#20 /app/vendor/yiisoft/session/src/SessionMiddleware.php(36): Psr\Http\Server\RequestHandlerInterface@anonymous->handle(Object(HttpSoft\Message\ServerRequest))
#21 /app/vendor/yiisoft/middleware-dispatcher/src/MiddlewareStack.php(104): Yiisoft\Session\SessionMiddleware->process(Object(HttpSoft\Message\ServerRequest), Object(Psr\Http\Server\RequestHandlerInterface@anonymous))
#22 /app/vendor/yiisoft/error-handler/src/Middleware/ErrorCatcher.php(135): Psr\Http\Server\RequestHandlerInterface@anonymous->handle(Object(HttpSoft\Message\ServerRequest))
#23 /app/vendor/yiisoft/middleware-dispatcher/src/MiddlewareStack.php(104): Yiisoft\ErrorHandler\Middleware\ErrorCatcher->process(Object(HttpSoft\Message\ServerRequest), Object(Psr\Http\Server\RequestHandlerInterface@anonymous))
#24 /app/vendor/yiisoft/middleware-dispatcher/src/MiddlewareStack.php(53): Psr\Http\Server\RequestHandlerInterface@anonymous->handle(Object(HttpSoft\Message\ServerRequest))
#25 /app/vendor/yiisoft/middleware-dispatcher/src/MiddlewareDispatcher.php(50): Yiisoft\Middleware\Dispatcher\MiddlewareStack->handle(Object(HttpSoft\Message\ServerRequest))
#26 /app/vendor/yiisoft/yii-http/src/Application.php(87): Yiisoft\Middleware\Dispatcher\MiddlewareDispatcher->dispatch(Object(HttpSoft\Message\ServerRequest), Object(App\Handler\NotFoundHandler))
#27 /app/vendor/yiisoft/yii-runner-http/src/HttpApplicationRunner.php(103): Yiisoft\Yii\Http\Application->handle(Object(HttpSoft\Message\ServerRequest))
#28 /app/public/index.php(36): Yiisoft\Yii\Runner\Http\HttpApplicationRunner->run()
#29 {main}

[albertborsos]

I had some time to dig deeper into it.

As @vjik said it is a problem, because it will try to call getCreated_at method.
If I replace it with

$methodName = 'get' . (new Inflector())->toPascalCase($field);

, then it will be OK, but it is still magic.

The next issue is with the following line:

data/src/Paginator/KeysetPaginator.php

Line 262 in 55fd808

$this->currentFirstValue = (string) $this->getValueFromItem($item, $field);

If the getValueFromItem returns a \DateTimeInterface then it is not possible to cast it to string.

data/src/Paginator/KeysetPaginator.php

Line 309 in 55fd808

$methodName = 'get' . ucfirst($field);

I made a new method:

    /**
     * @param mixed $item
     *
     * @return mixed
     */
    private function getStringValueFromItem($item, string $field): string
    {
        $value = $this->getValueFromItem($item, $field);
        if ($value instanceof \DateTimeImmutable) {
            return (string) $value->getTimestamp();
        }

        return (string) $value;
    }

And I replaced these two lines:

data/src/Paginator/KeysetPaginator.php

Line 262 in 55fd808

$this->currentFirstValue = (string) $this->getValueFromItem($item, $field);

data/src/Paginator/KeysetPaginator.php

Line 268 in 55fd808

$this->currentLastValue = (string) $this->getValueFromItem($item, $field);

to:

$this->currentFirstValue = $this->getStringValueFromItem($item, $field);

and

$this->currentLastValue = $this->getStringValueFromItem($item, $field);

After these modifications it sorts well for datetime fields too.
Of course there may be more values that cannot be casted to string.

[albertborsos]

Is there any reason the KeysetPaginator class is final?
I like in Yii 2.0 that I can easily extend the classes of the framework and I can use it if I configure it in the config files.

Now I would like to extend the KeysetPaginator class and fix it with my own methods while it is not fixed in this repository.
But it is not possible since this class is final.

[albertborsos]

I realised that KeysetPaginator is not good for my scenario (I just picked it from the demo app).

Because if I want to order by date, there could be multiple records with the same date, and KeysetPaginator will not know by the token which was the last record with the same date.

So I found OffsetPaginator which works great for my scenario.

[samdark]

@albertborsos would you please submit pull requests with your changes? Preferably separate ones but one PR would do as well.

Classes are final by default in Yii3. There are many advantages and disadvantages in this decision but that's how it is.

[albertborsos]

I close this issue, since I made a PR to access the field with the getter method.
The other issue I think is not a bug, I just used the wrong pagiantor.