Sometimes they will still get discovered by python even though their packages have since been uninstalled.
This will also lead to them being reloaded after an uninstall and a subsequent plugin reload.
Marking them as uninstalled and not handing out uninstalled plugins when collecting them solves this.
Added phase specific hooks for queuing, queued, sending and sent phases of a command ("octoprint.comm.protocol.gcode.<phase>"). Removed old queuing phase hook and declared as obsolete hook in plugin manager to prevent plugins that depend on it from being enabled.
Adding those new hooks also necessitated refactoring the whole command processing, made it more modular and added phase specific handler functions that allow handling all blocking commands centrally for example.
Since it cannot be reliably determined by the system if a hook is essential for a plugin's functionality or not, it makes more sense to just disable plugins that utilize obsolete hooks then risk running half working plugins.
The new hook allows extending the list of rules for maximum body sizes differing from the default of 100KB and can be used by plugins to allow uploads to them that exceed that file size.
Also extended the plugin manager to detect plugins that implement restart needing hooks (such as the above one) and handling those plugins the same as plugins containing implementations that inherit from octoprint.plugin.core.RestartNeedingPlugin
Plugins may be enabled and disabled during runtime. If they are of types which allow hot loading, this will be done. Otherwise they will be marked as pending and updated after a restart. Same for installation and uninstallation.
Plugins may be loaded, unloaded, activated and deactivated. Errors while trying to load a plugin or initializing an implementation will only result in it staying deactive but registered in the system, allowing it to be further processed e.g. by a plugin manager
Multiple mixins are allowed of course. Allowing multiple implementations lead to too many problems due to plugin names for referring to the APIs of SimpleApiPlugins or the assets of AssetPlugins.
Hence __plugin_implementations__ has been deprecated in favor of __plugin_implementation__. The plugin subsystem will automatically copy the first implementation from __plugin_implementations__ to __plugin_implementation__ and log a deprecation warning.
Adjusted documentation accordingly. Also added docs for helpers.
Detected plugins are now logged in a better readable way and with additional information.
Also marked folder for bundled plugins as bundled - forgot to do that earlier.
Preprocessing for better performancy, unit tests for preprocessing, controls don't need a type anymore (makes things way less complicated and repetitive)
Added wrappers to ensure existing plugins being able to work, although them using the old camel case method names now causes a deprecation warning being logged
Should catch any exceptions thrown by the plugin, log them and only hand them off if the caller requested to be informed about such things. This way if something goes wrong with a StartupPlugin there should be no problem anymore to still get the server up and running.
This data can still be overwritten from within the Plugin itself by setting the correponding __plugin_xyz__ variables, however it allows getting rid of some repetition if that data has already been specified in setup.py
