This is something that sites like Furaffinity can do and even other Boorus like rule34 paheal and rule34 xxx seem to do this. Why can't we? We're the most 'art theft woke' of any booru with our huge DNP lists, I find it odd that the code can't just include the artist credit in the saved filename by default. It would discourage art theft.

it might be a limitation of the file server — being able to strip off the prefix present in the url to obtain the real filename like danbooru's does

it would also be cache-unfriendly (i.e. cloudflare & browser) if tags are getting changed; in the case of huge files (like 100MB videos) the difference may not be entirely negligible

i'm only speculating though

People could just rename the files after downloading them.
The reason files are named like they are, is because they are the md5 checksum of the file it's self, which has various benefits:
1. Users can ensure they don't download duplicates
2. File server path is easier to resolve
3. Changing artist name would mean the file server has to be updated, which could result in race conditions(tags updated, file name isn't, user is presented with a file that doesn't exist because it hasn't been renamed), or dead links from people hotlinking
While it would be possible to use download="some name.png", the human issue of renaming files manually is still there.

sexyjackruby said:
This is something that sites like Furaffinity can do and even other Boorus like rule34 paheal and rule34 xxx seem to do this. Why can't we? We're the most 'art theft woke' of any booru with our huge DNP lists, I find it odd that the code can't just include the artist credit in the saved filename by default. It would discourage art theft.

"Furaffinity can do" completely bypasses why that is.
FA stores the files according to the account that uploaded it, so the name of account which uploaded the file is present in the filename, not the artist. Meanwhile here we have all the files in big pool, uploader is less critical information and tags can be changed constantly and we have even had situations of people misstagging artists.

Also last time I checked, xxx also uses MD5. Paheal actually uses format <ID> - <Tags>.<filetype> under MD5 folder, which is feasable as they only allow couple tags to begin with, artist tag in there is most likely just byproduct of this scheme and having paheal specific ID makes you go to their site when you need to reverse search it.

Additionally MD5 is useful as you can search MD5:<MD5 hash> status:any or https://e621.net/posts?md5=<MD5 hash> to find the image.

Like chaser said, it would be possible to make the download button to change the filename according to current data on the post page and make it download the file, but if I remember correctly, people were annoyed that download button actually downloaded the file, rather than just opening the file URL.

There's definitely nice intentions behind the idea, but practically not too useful.

I know this is a slightly different topic, but...

Sometimes, it would be helpful if the file name were stored somewhere in the post.
Maybe in a new field created exactly for this purpose.

There's always a file name, whether you upload the file from the web or from your computer.
Yes, if you upload a file from your computer, the full path shouldn't be stored on e621.
Only the part after the last path separator, to protect the uploader's privacy.
Example:
full path = /home/munkelzahn/Images/perverted_pony_porn.png
file name = perverted_pony_porn.png

This already happens for files uploaded from the web.
The direct image link is automatically put in the Source field.
Maybe this could be done for files uploaded from your computer, too?

I realize that many file names are useless, e.g. Tumblr ones.
But sometimes, they contain information that would help people find the source and/or artist on posts that lack this information.

In the case of FurAffinity, the file name contains the name of the FA account.
So OP's suggestion could be implemented like this.

mairo said:
Like chaser said, it would be possible to make the download button to change the filename according to current data on the post page and make it download the file, but if I remember correctly, people were annoyed that download button actually downloaded the file, rather than just opening the file URL.

Could always have two buttons - the "download" button downloads the image with a human-readable name via the download attribute, "fullscreen" opens it in browser.

It's much less of a problem than people make it out to be.

I just wish we had the option to download files with the post number the way Derpibooru does.

I'm pretty sure there's a simple way of setting the name of the file upon download, which would make it a rather easy toggleable feature rather than something that requires an entire restructuring of e621's file storage and doesn't cause any issues with caching since the image is always going to be at the same URL.

If that is the case, somebody could probably make a userscript easy enough too.

EDIT: It's actually easier - the <a> tag has a download attribute, so it'd be as simple as:

<a href="https://static1.e621.net/data/1c/15/1c159b981ca68b62cecf10f9a8ca3eeb.jpg" download="post-2185323.jpg">Download</a>

faucet said:
If that is the case, somebody could probably make a userscript easy enough too.

RE621 does that already, among many other things.
I made it user-customizable too. You can use a bunch of variables in whatever order you wish to match whatever file naming scheme you want.