[Digikam-users] Multiuser/nfs

[Simon Cropper]

On 24/02/13 06:17, Frank wrote:
> I know this was discussed/mentioned/requested before, but I didn't found
> newer post to that.
> Here is my network setup: debian server (nfs/IMAP/homes), 4 users (me,
> wife, 2 children), several clients, usable by all users.
> I have some groups set up (e.g "users" for me and my wife). All relevant
> data is stored on a nfs share at the server (to make backups easy).
>
> I understand, that it is now possible to use MySQL instead of SQLite as
> database, which overcomes the nfs-share issues.
> But I didn't understand, if that means I have multiuser support in
> digikam also.
> I don't really need full multiuser support on the database side. It
> would be sufficient to prevent digikam to start, when another user is
> accessing the database (e.g. via a starting script, which tells which
> user is accessing the database intead of starting digikam).
>
> But I need some help to sort this out, because of rather low level
> skills on the database site.
>
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>

Frank,

My understanding is that *digiKam is not multiuser*. Only one person can 
use you package at a time.

If say you were all in one room and could see that no one was running 
digiKam you could access the database and images on each of the machines.

The prerequisite is that the underlying directory structure remains the 
same. For example, ensure all machines have a IMAGES directory with the 
albums underneath in your mnt or media directory. Then the image 
locations will not differ between the machines.

The problem then is how to prevent others from accessing the package and 
potentially causing corruption of a file or database by reading/writing 
at the same time you attempt to read/write. The scenario when you are 
not all in the same room!

Personally I would write a simple bash script to replace my launchers.
Remove or hide all launchers on each machine and replace them with the 
bash script.

In simple pseudo-code the script would read...

- Check for lock file (simple text file in IMAGE directory)

- IF PRESENT,
   - throw a message to user (if you want to say who has it
     open save the user name in the text file and display that in
     message)

- IF ABSENT
   - create a lock file in the IMAGES directory (optionally containing
     the user name)
   - open digiKam
   - delete the lock file

If you need so help getting started with a bash script, email me off 
list and I can give you a skeleton program to get you started.

-- 
Cheers Simon

    Simon Cropper - Open Content Creator

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