Installing and uninstalling plugins

[mkanet]

With almost a quarter of a century dealing with the world of Microsoft windows, I have come to realize that even some of the best installers/uninstallers, after uninstalling an app, it's a sure bet there's going to be some sort of remnant left behind. Most software engineers could care less if there's a file somwhere on the file system or registry key still left behind.

I want to know if I install a plugin on sageTV, then uninstall it. What get's left behind? Something tells me that its not going to be 100% exactly like before the plugin was installed.

Is there a way for me to know exactly what gets installed and what is left behind after an uninstall (not disabling a plugin).

Im starting notice these files with .5 and similar at the end of each file. I'm guessing its some kind of version tracking system. Is there a way to clean up any traces at all of things that may have gotten left behind after a plugin uninstall?

I doubt too many people would understand the logic behind it; especially if it wont affect functionality. I guess, Im just a stickler for having a super clean system.

For example, I really want to install that recipe program. But not sure if I'll like it. How do I know somthing minor gets left behind in studio (similar concept to Windows registry).

-Michael

[GKusnick]

Originally Posted by mkanet

How do I know somthing minor gets left behind in studio (similar concept to Windows registry).

Plugin installers don't insert anything into the stock STV as it exists on disk. Rather, UI Mod plugins are loaded dynamically when SageTV starts. If you uninstall (or simply disable) a UI Mod plugin, it will no longer be loaded at runtime. The UI changes made by these plugins apply only during the sessions in which the plugin is loaded and are not written back to disk, so there's nothing to undo when the plugin is uninstalled.

The same goes for General plugins written in Java. If the plugin is disabled or uninstalled, it won't be loaded and its code won't execute.

The only real cause for concern might be Library plugins that are installed as dependencies of other plugins. In this case, uninstalling the dependent plugin won't automatically uninstall the library, so the library code will remain in the classpath where it could conceivably still be invoked by some other active plugin.

If you're paranoid, your best bet is to image your system before installing any plugin, and restore the image if you want to remove the plugin completely. (You should obviously back up your Wiz.bin separately to keep it from being lost during the image restore.)

[mkanet]

Greg, this is exactly what I thought. That's also why I do make a image backup after installing programs and configurations I know I will keep. It might be a little bit of overkill to make a backup image of my whole boot partition just to see if I like the tiny recipe plugin.

Originally Posted by GKusnick

Plugin installers don't insert anything into the stock STV as it exists on disk. Rather, UI Mod plugins are loaded dynamically when SageTV starts. If you uninstall (or simply disable) a UI Mod plugin, it will no longer be loaded at runtime. The UI changes made by these plugins apply only during the sessions in which the plugin is loaded and are not written back to disk, so there's nothing to undo when the plugin is uninstalled.

The same goes for General plugins written in Java. If the plugin is disabled or uninstalled, it won't be loaded and its code won't execute.

The only real cause for concern might be Library plugins that are installed as dependencies of other plugins. In this case, uninstalling the dependent plugin won't automatically uninstall the library, so the library code will remain in the classpath where it could conceivably still be invoked by some other active plugin.

If you're paranoid, your best bet is to image your system before installing any plugin, and restore the image if you want to remove the plugin completely. (You should obviously back up your Wiz.bin separately to keep it from being lost during the image restore.)

[Narflex]

You can trust that the install/uninstall of a plugin will leave your system in the same functional state. I actually don't have any problems doing this on my main development system where it's important to be sure I have a consistent system. I designed the plugin installation system, so I know exactly what it creates and what it will remove; so I wouldn't have any concerns about it if I were you. Just don't go deleting those .5 (or whatever #) files or messing with filetracker.properties and everything will be fine.

[stuckless]

Michael, I would think with 25 years on windows, you'd be totally desensitized to the who application litter syndrome that accompanies a Windows application

I think that the plugin system does a fairly good job of cleaning up, but there are 3 other areas that do not get cleaned up after an uninstall;

1. Properties in the Sage.properties (ie, phoenux/* properties)
2. Files added to the filesystem that were not in the package (ie, fanart, caches, etc)
3. Information in the Wiz.bin (ie, metadata, etc)

I don't think a plugin gets notified about when it's being removed. If it did, then it could perhaps clean up that residual information as well. Altough I'm not sure how happy people would be if when they uninstalled bmt, that I removed their fanart, phoenix properties, and cleaned their Wiz.bin of any custom metadata fields. I'm just using my plugin as an example here, because it's probably one of the plugins that does create a large amount of litter.

Maybe I can create a "BMT Uninstall" plugin that simply cleans all that residual information

[mkanet]

All I have to say is, you wont need to make a BMT Uninstall. I couldnt imagine someone wanting to uninstall BMT/phoenix. Not sure what will happen when ortus comes around.

Yeah, I can't stand having residuals of items I have uninstalled. Which is why I go through my client properties files with a fine toothed comb to make sure there are no entries from something I'm not using anymore. Unless I'm 100% sure a jar is no longer needed (like the old Netflix jar) and respective entries, files I wont touch them.

Originally Posted by stuckless

Michael, I would think with 25 years on windows, you'd be totally desensitized to the who application litter syndrome that accompanies a Windows application

I think that the plugin system does a fairly good job of cleaning up, but there are 3 other areas that do not get cleaned up after an uninstall;

1. Properties in the Sage.properties (ie, phoenux/* properties)
2. Files added to the filesystem that were not in the package (ie, fanart, caches, etc)
3. Information in the Wiz.bin (ie, metadata, etc)

I don't think a plugin gets notified about when it's being removed. If it did, then it could perhaps clean up that residual information as well. Altough I'm not sure how happy people would be if when they uninstalled bmt, that I removed their fanart, phoenix properties, and cleaned their Wiz.bin of any custom metadata fields. I'm just using my plugin as an example here, because it's probably one of the plugins that does create a large amount of litter.

Maybe I can create a "BMT Uninstall" plugin that simply cleans all that residual information

[Narflex]

Actually, I was reminded today about something a plugin did which the uninstaller didn't fix. When plugins change settings in the Sage.properties file while they are executing, the core can't be aware of that and won't undo them. The only nasty thing I've found so far with this is one plugin that changes the epg import plugin and then can cause you to not be able to properly get a list of EPG providers if you then uninstall that plugin (I'm pretty sure it's the Web Radio Guide). But I just had that fixed for the next build so it won't cause people problems anymore. (if it detects the EPG Import Plugin can't load, then it will just disable it)