[GUI Plugin] Action Chains

[jbacelar]

Edit: Although I have taken a look at the Import List plugin, and unfortunately it does not work for me, since I have several csv files that do not use title, and some neither title nor author, (they are based on custom columns).

[ownedbycats]

I'm not sure if it's worth fixing, but the "spinning cursor in dialog" appears for some of the Kobo Utilities dialogs (Store/Restore Bookmarks, Upload Cover, and Set Reader Font). I've otherwise run into no problems using those actions in a chain.

[capink]

Originally Posted by ownedbycats

I'm not sure if it's worth fixing, but the "spinning cursor in dialog" appears for some of the Kobo Utilities dialogs (Store/Restore Bookmarks, Upload Cover, and Set Reader Font). I've otherwise run into no problems using those actions in a chain.

As I already mentioned before, not really possible unless someone knows a way to programmatically detect whether a calibre action pops up dialog. The other solution is to disable the busy cursor for all calibre actions which I don't want to do.

Originally Posted by capink

The plugin starts a busy cursor that remains active from the start of the chain until it ends. I will modify it to temporarily turn it off during the popups of single field dialogs. The same cannot be done however for dialogs from Calibre Actions (e.g. Edit metadata dialog) because I have to track every possible action and see whether it pops up a dialog or not.

Edit: I might add a checkbox in the calibre action settings dialog to enable/disable it.

[ownedbycats]

Ah, either I missed or forgot about that post. Sorry.

[capink]

As I said in the edit of the previous post, a possible solution is to present the user with a checkbox to turn it off/on as he sees fit for the particular action.

[ownedbycats]

Also, I wonder if it would be possible to make an option to grey out certain chains if the device isn't plugged in. It's a bit of a niche thing though, and there's no harm if I try to run the chain with no device (it just fails).

[capink]

Originally Posted by ownedbycats

Also, I wonder if it would be possible to make an option to grey out certain chains if the device isn't plugged in. It's a bit of a niche thing though, and there's no harm if I try to run the chain with no device (it just fails).

The plugin cannot know in advance whether a chain depends on a device being plugged. The only way to do this is by adding checkbox in the chain dialog that would disable the chain when no devices are plugged. I really don't want to clutter the chain dialog with extra options unless absolutely necessary, so will leave it for now.

[ownedbycats]

Also, this plugin puts this xkcd comic into mind:

[Terisa de morgan]

Originally Posted by ownedbycats

Also, this plugin puts this xkcd comic into mind:

[compurandom]

I would like to calculate a value and then use it in a action chain.

Specifically, I want to check which of two devices is connected (I know how to do that), and then either search for books with a (device specific) tag along with other search parameters, or pick a specific premade search (depending on which device), and remove the tag, along with other device non-specific actions on the same set of books.

If I could branch within the chain, that would make this easy, but it would be easier if I could pick a search or use a calculated constant...

Is there a way to do this currently? (or could it be added?)

Edit: I think I figured out how to do it (untested yet) by just prefixing the chain with a search that will come up empty on the wrong device and then duplicating the chain for each device. But it would be more elegant if I could use a calculated value.

[chaley]

Originally Posted by compurandom

I would like to calculate a value and then use it in a action chain.

Specifically, I want to check which of two devices is connected (I know how to do that), and then either search for books with a (device specific) tag along with other search parameters, or pick a specific premade search (depending on which device), and remove the tag, along with other device non-specific actions on the same set of books.

If I could branch within the chain, that would make this easy, but it would be easier if I could pick a search or use a calculated constant...

Is there a way to do this currently? (or could it be added?)

Edit: I think I figured out how to do it (untested yet) by just prefixing the chain with a search that will come up empty on the wrong device and then duplicating the chain for each device. But it would be more elegant if I could use a calculated value.

I confess I don't fully understand what you want to do, but it seems that using a template search might do the trick. See the description of template searches in https://manual.calibre-ebook.com/gui...arch-interface.

[capink]

I don't understand what exactly you are trying to achieve, but I will address the question of branching in general. There are two ways to do it:

Edit: Starting with version 0.4.0, action chains introduced a conditions feature that allows the user to run actions based on conditions at runtime. This also allows branching.

• For people who don't write code the only way to do it, is exactly as you discovered yourself (and as I pointed here before) by making search that return empty results (if condition is not met) in which case actions running will not have real effect, after that another search might return results that actions will act on and so so on.
  
• The other alternative involves writing a custom action that does the branching for you, and creating a master chain that contains that action. You also have to create separate chains containing the different branches (they can be all grouped in one submenu). In your master chain's custom action, you test the conditions and call the appropriate chain like illustrated below.
  
  

  from calibre_plugins.action_chains.chains import Chain
  from calibre_plugins.action_chains.actions.base import ChainAction
  import calibre_plugins.action_chains.config as cfg
  
  class RunChain(ChainAction):
  
      name = 'Run Chain'
  
      def run(self, gui, settings, chain):
          chain_name = 'Your Chain Name'
          chain_config = cfg.get_chain_config(chain_name)
          my_new_chain = Chain(chain.plugin_action, chain_config)
          my_new_chain.run()

On a side note, I thought about giving the users the ability to call other chains through Calibre Actions or through a separate action, and maybe supplementing that with a another flow control action. I dismissed the idea because it can cause problems like circular dependency. You can prevent a chain from directly calling itself, but it can do so indirectly through another chain that might reference it, and this would require a complicated dependency checking before running chains. You can write these action(s) for yourself as custom actions if you want this be a generalized solution, but I think it is opening a can of worms.

[ownedbycats]

Originally Posted by capink

I dismissed the idea because it can cause problems like circular dependency. You can prevent a chain from directly calling itself, but it can do so indirectly through another chain that might reference it, and this would require a complicated dependency checking before running chains. You can write these action(s) for yourself as custom actions if you want this be a generalized solution, but I think it is opening a can of worms.

- Start ActionChain#1
- It calls ActionChain#2
- But then that calls ActionChain#1
- Which again calls ActionChain#2
- And once again, it calls ActionChain#1...

I don't think there's any good way to halt a chain in progress, is there?

[capink]

Originally Posted by ownedbycats

I don't think there's any good way to halt a chain in progress, is there?

You can cache the names of the chains as they run, and once you detect a chain running for the second time, halt the whole process with an exception. It is just not a good idea to halt a chain midway. The difficult part is checking before the chain runs.

[ownedbycats]

I've accidentally fork bombed my computer while trying to put together a batch file. That was fun.