Filter list when site inaccessible is not kept

[ghost]

I noticed yesterday when updating my filter lists that one of the sites delivering one of my custom lists was inaccessible. Unfortunately the list itself as it was before update had been removed.
I understand that updating a list is a mirror update and therefor list is removed before being updated.

Would it be possible that the active list not be removed before access to the delivering site is validated?

The site's list is AntiPubWeb, unfortunately not https but excellent for it's filter list (originally for AdblockPlus/Edge) concerning many sites in France. Yesterday the site had problems and as mentioned above the ~8000 filters had all been removed. Fortunately I always backup my Firefox profile. But whatever source the problem could arise again.

uBlock 0.8.6.0 on Firefox 35.0.1

Thanks

[gorhill]

Would it be possible that the active list not be removed before access to the delivering site is validated?

That's how it works. If the locally cached copy was removed, it's because uBlock was told that the downloading of the remote resource worked all fine. So for this to happen is because the site did not return an error, and the resource returned was not an empty file -- the condition required for uBlock to not clobber the cached version.

There is not really anything uBlock can do if the remote server is not giving good information to uBlock.

[gorhill]

So the site must have sent an 200 OK status code, along with an empty file. I thought I had put some safeguard in there against empty files, but looking at the code I don't see this for when an OK code is sent back.

[ghost]

Well, that site did have big problems yesterday indeed, not sending an error included (or moreover a '200 OK' performed). I had called its filter list url from the browser and access was impossible indeed but from the browser hard to tell what's going on, especially for a non techie).
Thanks again gorhill for this detailed answer. I'm not a techie as you can guess so my comments have the evidence of being simple :)

You learn every day.

[gorhill]

Not so fast, I corrected myself above.

[ghost]

@gorhill commented on 6 févr. 2015 13:16 UTC+1:

Not so fast, I corrected myself above.

Yep, I saw it, thanks. I'll leave my post open, up to you to decide if it is to be closed.