Why does XF keep image data for a few hours, even after the user deletes it? This was brought to my attention when Felicia mentioned that it is preferable to reference an image url versus uploading the image to the forum's server. (link) She gave two good reasons for this, which were: Images take up space on the server. Once you've uploaded the image to the server you, as a user, cannot delete it yourself. I was skeptical about whether the image would remain on the server even after deletion by the user so I tested it out. Sure enough, the jpg file was still in the directory even after I deleted it. Perturbed by this, as I thought a user should have control over their own images, even on someone else's server, I began to write this post for 21C, with the intention of taking it to the XF community once I'd laid out my question more clearly. Luckily, though, before I got myself all tied up in knots about this, I was pulled away from my computer for a bit, and when I came back, the file was gone! It seemed there was an interval between the time data was entered into the forums and when it was deleted from the server. Here is how that went down in screenshots: The reverse, writing an image to the server, however, takes place immediately, which I was also able to confirm. Here you can see the newly written file alongside the deleted file: My theory is that the deleted file will not be present when I check back later. Either way, this has been interesting to see how XF handles uploaded images. My concern is not only that the user should have control of their images on the forum's server, but that encouraging the outgoing urls will appear to compromise the security of the forums.
Aha! It happened again. It took a bit of time for the file to be deleted from the server, but it did disappear eventually. Conclusion: Users can delete their own images from the server--as long as they're patient.