4.2.5 overwrites files if file names are the same

[ned-martin]

qBittorrent version and Operating System

4.2.5x64 / Windows 10 (10.0.1xxxx)

What is the problem

When "Create subfolder for torrents with multiple files" is enabled, and more than one torrent of the same name, and/or containing one or more files of the same name, begins to download, it overwrites the other one, resulted in lost data, and the torrent re-downloading again (which then repeats the process, the torrents would likely never complete)

What is the expected behavior

The automatically-created subfolder should use common collision avoidance naming rules, for example, Folder, Folder (1), Folder (2)

Alternatively, if that's somehow impossible, a much worse solution would be that any new torrent could go into an error-state when it tries to start by detecting a name collision with an existing file and allow the user to choose to rectify the problem in some manner, by renaming the torrent or file/s for example.

Steps to reproduce

(I don't know if all of these options are required, but this is what I have set)
Enable "create subfolder for torrents with multiple/ files"
Enable "Append .!qB extension to incomplete files"
Default torrent management mode: Automatic
Default save path:
Keep incomplete torrents in:

I'm aware this issue has been reported before and is not specific to 4.2.5, but it seems to still persist and is a fundamental issue preventing the normal use of the program, that I can only assume would be trivial to fix.

[glassez]

"Create subfolder" does not create anything other than what is contained in the torrent.
Isn't the user telling qBittorrent to save torrent to a specific location? Why should someone else be responsible for this action?

[glassez]

I wonder what the probability is that different torrents have content with the same names...

[ned-martin]

"Create subfolder" does not create anything other than what is contained in the torrent.
Isn't the user telling qBittorrent to save torrent to a specific location? Why should someone else be responsible for this action?

I don't understand what the confusion is here. No, the user is not telling qBittorrent to save to a specific location, as you said yourself, the location is stored in the torrent (or is the name of the torrent). In fact, in my experience, until the torrent starts downloading, the user can't even rename the location - because until the torrent gets the data of the files in it, there's no way to know.

No program should overwrite user data. Surely that's just a given? Would you be ok with any other program doing this? Let's say you're using your internet browser, and you decide to download a picture. It doesn't prompt you for any file collision, and instead just overwrites some other important photo you already had saved. Would you be ok with that? No, of course not. You'd be very angry. Well, I'm not ok with qBittorrent doing it either.

I wonder what the probability is that different torrents have content with the same names...

Very high. It happens all the time. Personally, I had it happen to three different torrents yesterday, losing several GB of data which had taken many hours to download, which is why I posted this.

Here's an example that demonstrates how this happens, and why this is a common problem:

• Decide to download a file, let's call it "Centos 8"
• Go searching for torrents called "Centos 8"
• Find 18 torrents called "Centos 8"
• Add all 18 torrents because they all look like they'll struggle to download and no one is seeding
• (Note that several of these torrents are magnet-only links, so it's not possible for the user at this stage to actually see what's inside them, and also not possible to rename what's inside them, so it's impossible to find out if they'll conflict with an existing file that's being downloaded or not - and if they start in the middle of the night when the user isn't there to watch them, then they'll overwrite data automatically)
• One of the torrents starts downloading, creating a sub-folder called "Centos 8" with a file in it called "Centos8.iso"
• Many, many hours later this torrent is completed! Joy!
• A second torrent starts to download, creating a folder called "Centos 8", with a file in it called "Centos8.iso"...
• Downloaded data is now permanently gone.

There appears to be two ways this goes wrong:

1. One torrent completes, then a second one starts, and when it completes, it overwrites the first one
2. Two or more torrents download at the same time, overwriting each other as they go along

Note: all the torrents I had problems with yesterday seemed to contain folders themselves, so the sub-folder that was created was contained within the torrent - it was not auto-created from the torrent name. I am unsure if this is a relevant factor. The problem is the same though - qBittorrent should not overwrite files or folders - it should auto-rename them, or a worse solution, put that torrent into an error state and pause it until the user can come fix the problem.

[FranciscoPombal]

Well, I guess qBittorrent should not silently overwrite data like this without at least some kind of warning just because the user changed an option that does not really imply that such a destructive action could happen.

[glassez]

just because the user changed an option that does not really imply that such a destructive action could happen.

What "option" do you talk about?
The problem is the user add multiple torrents with same-name files/folders to be stored in the same location.

Let's say you're using your internet browser, and you decide to download a picture. It doesn't prompt you for any file collision, and instead just overwrites some other important photo you already had saved. Would you be ok with that?

No, I'm not OK with it. But it's incorrect example.
Pointing torrent to the location with existing files is regular case. There can be files previously downloaded (fully or partially) by the same or other torrent or even obtained from other sources but matching (fully or partially) the files in the torrent so that the user may want to use them...

[FranciscoPombal]

@glassez

Pointing torrent to the location with existing files is regular case. There can be files previously downloaded (fully or partially) by the same or other torrent or even obtained from other sources but matching (fully or partially) the files in the torrent so that the user may want to use them...

Yes, allowing existing files to be is used supports use cases such as "cross-seeding" for example. But why not ask the user first? That way its still possible to use existing files for "cross-seeding" and also prevent overwriting when that is not desirable.

[ned-martin]

@glassez

Pointing torrent to the location with existing files is regular case. There can be files previously downloaded (fully or partially) by the same or other torrent or even obtained from other sources but matching (fully or partially) the files in the torrent so that the user may want to use them...

Yes, allowing existing files to be is used supports use cases such as "cross-seeding" for example. But why not ask the user first? That way its still possible to use existing files for "cross-seeding" and also prevent overwriting when that is not desirable.

If you want to allow existing files to be "used" by a torrent, then you should add some mechanism to do so - I'd suggest a menu to "import data to existing torrent" or similar.

Either way, this is not really the same situation.

In my situation, all torrents download to one location. All completed torrents are then moved to another location. That's pretty much the only options the UI gives as far as I can tell, but it seems to also be the only logical way to do things.

Here is a simple scenario to indicate why this is a big problem, which I believe is quite common:

1. User queues up 2 torrents to download and goes to bed. User knows both torrents are the same or similar data, though user doesn't know if they have the same filenames or not, but the user thinks that the chances of either download actually working is low because this seems to be a rare and hard to find torrent, so the user has to queue up both of them to increase the chances of either one actually downloading.
2. Note that it is not necessarily possible for the user (or the system) to know the exact file names of these torrents at this stage, because the torrents may be magnet links with no associated names or metadata, or the user might be using a third-party search scraper like Jackett or the python ones that are included with qBittorrent which only gives an overall name, not the exact torrent names. Either way, the user doesn't want to spend ages trying to research if the torrents have the same name as each other, because that's absurd - no other software the user has ever used would overwrite stuff like this, so the user assumes that qBittorrent will be able to correctly download torrents - that is, after all, its sole purpose.
3. In the middle of the night the two torrents find some peers, download their metadata, and suddenly they have the same name and/or contain the same files! The user is asleep and does not know this.
4. The torrents start to download. The user is still asleep, dreaming of how good it will be in the morning when the data is downloaded.
5. The torrents will overwrite each other!
6. The user wakes up to find out that one of the torrents completed in the middle of the night. It even sent the user an email to tell them it was completed! Yay!
7. Unfortunately, early in the morning before the user woke up, the other torrent then started downloading as well and overwrote the first torrent, and now both of them are at 3% downloaded, or one of them has gone into an error state of "missing files". The user has no data! This sucks!
8. The user is angry at qBittorrent because it's got such a crap bug that means it can't properly download torrents - pretty much the one job it's supposed to be able to do. The user could just give up and go use one of the many other torrent programs that don't have this ridiculous bug, but the user would like to try to improve the program so logs this bug (again - it's been logged many times before)
9. The user is really surprised that other people seem to find it hard to understand how this is a serious problem, but in the interests of fairness, the user would like to hear from other people how they use qBittorrent without this issue, and why they don't see how this is a serious issue? Is the user doing something wrong? Is there some way to use qBittorrent the user doesn't realise, where it can reliably download things without overwriting other things?

[nokti]

This is a situation that has happened to me several times, so it's not an uncommon occurence. If my memory si correct µTorrent 2.2.1 solves that problem by automatically adding a numerical to identical folders, like Folder (1) (or was it Folder.1). It would be very useful if qBit could do the same.

[conkerts]

Actually weird, that I searched for same filenames, but haven't found this bug report in the search.

I wonder what the probability is that different torrents have content with the same names...

I'm actually surprised that there are several resports of that especially in the last few months.

This is a situation that has happened to me several times, so it's not an uncommon occurence. If my memory si correct µTorrent 2.2.1 solves that problem by automatically adding a numerical to identical folders, like Folder (1) (or was it Folder.1). It would be very useful if qBit could do the same.

Yes, looks like it is indeed more common than I expected.
At least some warning for the user would be nice and useful
I mean there is no real problem if the files are supposed to be the same. But then only let one copy be actively downloaded.

In case with same file name and different checksum, just refuse to proceed or do it the utorrent way, yes, that sounds like an easy solution, too

[ned-martin]

I mean there is no real problem if the files are supposed to be the same. But then only let one copy be actively downloaded.

No, this would not be good. I often want to download the same file multiple times simultaneously. Just act like every other software on earth, and let the user choose what they want to download, without automatically overwriting anything else!

Two examples:

1: Downloading 2 same files on purpose:

• I want to download a file, but sadly I can only find partially-seeded unreliable torrents for it. So I queue up more than one in the hope that later on more peers will come online. So I am now downloading 2 or more of the same file (but different torrents). I want all of these to keep trying to download because the chances of completion for a poorly-seeded torrent are quite low and it might take days or weeks.

2: Downloading 2 same files by accident

• I want to download a file, but I only have magnet links. I don't know what the filename is inside the torrent as I don't have that info in the magnet link, so I queue up more than one magnet link in the hope that at least one will download. Then later when I'm asleep, the magnet links find some peers and it turns out they contain the same files - I had no way of knowing that when I queued it up and I can't deal with it as I'm asleep. The system needs to deal with it by renaming one.