The plug-in auto loader mechanism allows for easier deployment of custom applications using a package format.
The package format is a common folder structure that has the extension .bundle in its name and has an XML file that defines the various components of the plug-in. By deploying custom applications as a BUNDLE, it makes it easier to target multiple operating systems and product releases since the parameters of your plug-in are defined in the XML file of the package. A BUNDLE can be used as a replacement to creating complex installer scripts when deploying a plug-in.
A plug-in can be deployed by placing it in one of the ApplicationPlugins or ApplicationAddins folders on a local drive.
When an AutoCAD-based product starts, the ApplicationPlugins or ApplicationAddins folders are checked for plug-ins. The plug-ins found are automatically registered and loaded based on the metadata in the XML file of each package.
Starting with AutoCAD 2016-based products on Windows, it is recommended to digitally sign your custom program files. By digitally signing a custom program file, you inform the user as to who published the custom program file and if any changes were made to the file after it was digitally signed. For information on digitally signing custom program files, see the "About Digitally Signing Custom Program Files" topic.
Each custom program file loaded is check for the existence of a digital signature. If a digital signature is found attached to a custom program file, the user is presented with information about the digital certificate and publisher that signed the file. The user can choose to continue to load the file, and optionally trust all files by the publisher of the file being loaded. If no or an invalid digital signature is found, the user is informed that the program file might not be safe to load and execute.
A package can be deployed using an installer, such as MSI, or manually copying the files and folder structure to the ApplicationPlugins or ApplicationAddins folder. For Autodesk App Store downloads, deployment of the package is done using an MSI installer on Windows.
By default, plug-ins are automatically registered with an AutoCAD-based product and when a new plug-in is installed during the current session. The load behavior for plug-ins is controlled with the APPAUTOLOAD system variable. When APPAUTOLOAD is set to 0, no plug-ins are loaded unless the APPAUTOLOADER command is used.
A package can be uninstalled by removing the appropriate folder with a .bundle extension from the ApplicationPlugins or ApplicationAddins folder. This can be accomplished by offering an uninstall option with the original installer or to manually delete the .bundle folder.