Implemented Rare Cases of Generated Images with Zero Bytes length

Hi Ruud,

I use your pugin with Joomla 3.10 and my Website has a lot of Traffic and a huge amount of images in total (>10.000). 
When I enabled the Plugin for the first time (including webp conversion), some pages ran in timeouts and returned only a blank site. After limiting the cache Images creation to only one picture per request I did not experinced furthor timeouts.
But I found some pages where the image is missing. The img Tag is set including the srcset looks fine. One image  link (for the largest one) in the srcset is defect, the image is found but it is an empty ressource. In the imagecache folder, I found some images with an filesize of zero. After deleting these images, they where regenerated and show correctly in the page.

From time to time I found new images with an filesize of zero in the image cache folder. I am worry that some users might see these images as blank image too.

My guess is that in case of timeouts or other temporary exceptions there is a chance that the cached image is generated with zero bytes file size. It would be great, when those corrupt images are not delivered to clients over and over. I have two ideas to do so:
1) check not only the exist of the file but also if the filesize is greather zero
2) generate the image with temporary filename (eg. with postfix) and rename the file to the final file. The file would only be renamed if no exception occours.

Regards

Markus

DOWNLOADLINK to test version

Hi Markus, currently on holidays so short reply
Both your suggestions make sense! I will look into this and see what is best without generating extra overhead for each visitor

Hi Markus,

I have implemented the filesize check.
So now when one or more of the images in a fileset have filesize 0, they will be regerated on next visit of the page. When 0, the srcset will not be implemented, it wil then use the element unaltered (and thus always showing the image).

Test version (I have this version currently on this site), is available in the first post (yours) of this topic.

Let me know if this works for you.
thanks for your patience

regards,
Ruud.

Hi Ruud,

I had test your new version and it looks fine. I had created a second cache folder and intentionally use a slightly to hight image creation limit so the side has experinced sometimes a timeout. In the cachefolder a few images has a zero lenght but after a while they become a new size, so these . I also did not see any missing images on the site. Correct resized images won't be resized over and over.

Thanks for your fix!

Markus

Hi Markus,
thanks for testing. Change will be in in next release.
regards,
Ruud.

Just released version 1.16.0 with this change implemented