Flysystem: Streaming & Defensive Coding

Hey @Thanathan

Yes, you're right we didn't handle the cached image. As you already noticed there's a service to do that, you just need to send the same image path you send to the Filesystem service. But there's a gotcha, if you're using image filters, you need to specify them as well. Something like this

use Liip\ImagineBundle\Imagine\Cache\CacheManager;
use Liip\ImagineBundle\Imagine\Filter\FilterManager;

class ImagesRemover
{
    public function __construct(
        private CacheManager $cacheManager,
        private FilterManager $filterManager,
    ) {
    }
    
    public function clearCache(string $imagePath)
    {
        $this->cacheManager->remove(
            $imagePath, 
            array_keys($this->filterManager->getFilterConfiguration()->all())
        );
    }
}

That should do the trick. Cheers!

Hey @MolloKhan

Thanks for your prompt reply. 👍
I thought, I could omit the second parameter because of the documentations "Remove the cache for a specific image in all filter sets: $cacheManager->remove($path);"

But adding the second one doesn't hurt. 😉

My real problem is the value of $imagePath. How can i get the correct path of the image when we're using "flysystem"? That's the part I'm struggling with. I checked the methods our instantiated file system provides, but couldn't find a hint. Isn't there some kind of "returnPathForFile($filename)" magic?

I'm assuming you have a setup similar to what we have in this tutorial. You can see how Ryan deletes an image file here
https://symfonycasts.com/screencast/symfony-uploads/flysystem-defensive#codeblock-8abab61864

Basically, you grab the base path from somewhere, usually a constant or static method in a file, and append the name of the file that you stored in the Article object

I hope it helps. Cheers!

Hey Kirill,

I believe this is the video you're looking for https://symfonycasts.com/screencast/symfony4-fundamentals/logger-trait
By the way, at the top of the page, there's a search box where you can look for specific content just in this tutorial or through the whole site

Cheers!

Hey Kiuega !

Ah yes - a difference between Flysystem v1 and v2. I need to see if we need some notes to the video related to this!

I think what you're referring to, specifically, is this: https://flysystem.thephpleague.com/v2/docs/what-is-new/#no-more-success-result-booleans

So, in v2, life is actually simpler. You don't need to code as defensively because the operation will work or it will NOT work and you will get an exception (without us needing to if it worked).

The code you put above, I think, is close - but we can simplify a bit more :).

A) For the writeStream, there's no need to have a try/catch around this. Just call the method. Either it will work, or an exception will be thrown. So, it will have the same behavior that you see now (a different exception instance will be thrown, but that's fine).

B) For the delete, you technically don't need the try/catch here either, unless you wanted to avoid failing (500 error) if the file is not found. If that's what you want to accomplish, then your code is perfect: you're catching just that one type of error. I don't think you need the if ($existingFilename) part, but that's minor - and maybe there is more to your code that I'm not seeing.

Cheers!

Hey Kiuega

Looks like you did a good investigation! The code you did is a good alternative! Sorry that you got difficulties with this part of course.

Cheers!

Hey Cameron,

> Why are we closing something that already closes itself?

Actually, it's the reverse... Ryan says:

> The "if" is needed because some Flysystem adapters close the stream by themselves.

So we need that "if" to find *those* steams that were not closed by themselves... and if they were not - we close it ourselves in that if :)

Makes sense for you now?

Cheers!

Hey Krzysztof K.

That's a good question. I'm not sure if after throwing an error the resource will be closed automatically, or if it may introduce any bugs. So, if you want to play defensively you may want to close it first and then check for errors.

Cheers!