use of soft links for collections

[Remco Viëtor]

On mercredi 15 novembre 2017 17:55:47 CET Elle Stone wrote:
> On 11/15/2017 10:55 AM, jdd at dodin.org wrote:
> > Hello,
> > 
> > I have my collections spread on an usb disk by date, one by year
> > 
> > This begin to make many collections :-)
> > 
> > I try to make only one collection with inside links to real collections
> > 
> > collection
> > collection/linkto2017
> > collection/linkto2016
> > ...
> > 
> > this don't works, when it works perfectly on the system, for example
> > with dolphin
> 
> I'm not sure exactly what you are asking. But currently I have my actual
> image files in a partition on a large drive, and my Linux root and $HOME
> folders on a second, smaller drive. The digiKam database is in
> $HOME/digiKam.
> 
> My "Collections" folders are soft links in the $HOME/digiKam folder to
> the actual folders on the partition on the large drive, which is mounted
> at "/store".
> 
> So these are the folder paths where the images are actually located:
> 
> /store/camera_files
> /store/paintings_and_edited_images
> /store/to_be_deleted
> 
> And these are the corresponding soft links that digiKam sees as the
> Collections folders:
> 
> $HOME/digiKam/camera_files
> $HOME/digiKam/paintings_and_edited_images
> $HOME/digiKam/to_be_deleted
> 
> So far this seems to be working, but I only set it up a couple weeks
> ago. I've been using digiKam to do a lot of dragging and dropping of
> files between various subfolders and also into the "to_be_deleted"
> folder, which I've been periodically reviewing and emptying using Dolphin.
> 
> So far nothing seems to have gone wrong. But I'm still a bit leery of
> unknown traps and issues that might surface . . . Anyone with more
> long-term experience with using soft-links as Collections folders?
> 
> Best,
> Elle
How does Digikam react to missing directories/collections?

It looks like jdd never has more than a few of the collections mounted, while 
Elle has all the configured directories available at all times. As Digikam now 
optionally verifies directory changes and cleans up the database, unmounted 
directories might cause trouble.
Trouble as in "images in unmounted directories/collections are purged from the 
database", this won't remove any actual files, but could lead to loss of tags, 
captions and titles, if those aren't written to sidecars.

Don't forget that links to mount points point to (subdirectories of) actual 
directories, so Digikam will see a directory (which is probably empty if the 
drive isn't mounted, but that's not necessary; using a non-empty directory as 
a mount point just hides any files there for the duration), but without the 
expected image files...

Disabling the two mentioned startup checks through the Digikam configuration 
dialog might prevent this.

Oh, and @jdd: "this doesn't work" isn't very descriptive, so I had to take a 
guess at what "didn't work".

Remco