Can a library folder be operated on by two sessions of calibre?

[gkbeer]

Specifically, I have a Ubuntu box that operates a Calibre content server.
It also shares the folder containing the library out to the home network.

For the purpose of updating the library:
I want to run Calibre interactively from a laptop, with Calibre referencing the library folder, shared from the content server.

Do I need to stop the content server for the time that I am running Calibre interactively on the laptop?

No doubt both the content server and the laptop need to be running the same version of Calibre.

[EricLandes]

Originally Posted by gkbeer

Specifically, I have a Ubuntu box that operates a Calibre content server.
It also shares the folder containing the library out to the home network.

For the purpose of updating the library:
I want to run Calibre interactively from a laptop, with Calibre referencing the library folder, shared from the content server.

Do I need to stop the content server for the time that I am running Calibre interactively on the laptop?

No doubt both the content server and the laptop need to be running the same version of Calibre.

Only one installation should operate on a given library at any one point in time.

The key to the problem is metadata.db. If that file is open from one computer, changes made with the 2nd computer won't be recognized. You'll be able to successfully add files into the Calibre file system, but the original machine won't know they're in the database.

So, not a recommended practice.

What I do is run a small, secondary installation on my laptop. I add the new content there and get all the metadata the way I like. Then, I save to disk onto my server.

Then, I use the Calibre installation on the server and add the files there. It's the safest way if you want to run a content server.

[chaley]

You can run a content server against a database that is open read/write by calibre. The content server checks if the DB has changed and does its work again when the DB changes.

Two instances of calibre cannot access the database in read/write mode and expect good things to happen.

Although running the same version isn't always necessary, I, as a developer, am incapable of giving you the rules. That tells me that running the same version is a good idea.

Today has been a bad day for me and clarity. Do I make sense?

[EricLandes]

Originally Posted by chaley

You can run a content server against a database that is open read/write by calibre. The content server checks if the DB has changed and does its work again when the DB changes.

Two instances of calibre cannot access the database in read/write mode and expect good things to happen.

Although running the same version isn't always necessary, I, as a developer, am incapable of giving you the rules. That tells me that running the same version is a good idea.

Today has been a bad day for me and clarity. Do I make sense?

How do I run Calibre without opening the DB in read/write mode? Does just running the content server do this?

[kovidgoyal]

yes run the content server from the command line

calibre-server

[EricLandes]

Originally Posted by kovidgoyal

yes run the content server from the command line

calibre-server

Cool, thank you.

I need to explore the command-line portions more. I do everything exclusively from the GUI. Which is odd, because I'm a command-line kind of guy.

[Trickery]

Originally Posted by EricLandes

What I do is run a small, secondary installation on my laptop. I add the new content there and get all the metadata the way I like. Then, I save to disk onto my server.

Then, I use the Calibre installation on the server and add the files there. It's the safest way if you want to run a content server.

Ha, that would have been great to know awhile back. All I did was share the Calibre AppData folder and the folder containing all my eBooks over the network. Just run SyncToy, rsync, Allway Sync, whichever sync product you like.. and my server, laptops, and other desktop computers all have identical application settings and libraries at all times.

That way if I change some of the display settings/convert settings on one Calibre instance, they get transferred to the others.

[gkbeer]

Originally Posted by kovidgoyal

yes run the content server from the command line

calibre-server

With all the other responses I'm not sure if this reply was to my initial query. gkbeer

To clarify:

If I run Calibre-server from the command line on my home server (actually as a daemon), and share the library folder from that server as well. I may, from any other machine on my home net, run Calibre, interactively, and edit the library, of the server, without shutting down Calibre-server.

Usual caveats of keeping all systems on the same version of calibre apply.

Edit: New question, Can a single Calibre database be edited by multiple interactive sessions of Calibre?

[Trickery]

I believe both of your questions have been addressed.

Question:

Originally Posted by gkbeer

If I run Calibre-server from the command line on my home server (actually as a daemon), and share the library folder from that server as well. I may, from any other machine on my home net, run Calibre, interactively, and edit the library, of the server, without shutting down Calibre-server.

Answer:

You can run a content server against a database that is open read/write by calibre. The content server checks if the DB has changed and does its work again when the DB changes.

Question:

Originally Posted by gkbeer

Edit: New question, Can a single Calibre database be edited by multiple interactive sessions of Calibre?

Answer:

Originally Posted by EricLandes

Only one installation should operate on a given library at any one point in time.

The key to the problem is metadata.db. If that file is open from one computer, changes made with the 2nd computer won't be recognized. You'll be able to successfully add files into the Calibre file system, but the original machine won't know they're in the database.

So, not a recommended practice.

So yes, if you run the content server as a daemon you have no problem making changes to the library. The content server daemon will use the updated library. Also to answer your second question, you can have multiple computers with calibre pointing to a network folder making changes to a library. Just don't have calibre running on multiple computers or make changes at the same time or it could cause problems.

[DoctorOhh]

Originally Posted by gkbeer

If I run Calibre-server from the command line on my home server (actually as a daemon), and share the library folder from that server as well. I may, from any other machine on my home net, run Calibre, interactively, and edit the library, of the server, without shutting down Calibre-server.

Yes .

Originally Posted by gkbeer

New question, Can a single Calibre database be edited by multiple interactive sessions of Calibre?

Not at the same time. Only one session of calibre should interact with the calibre database at any given time. Bad things may happen if multiple users access/modify the database from multiple locations at the same time.