The basic file structure for your module will be divided into two sections, the admin and the catalog folders. The contents of each folder will follow the MVC-L framework respectively, with the difference that the admin will deal solely with backend functionality, and the catalog with frontend functionality. Users of your module will interact and configure its settings in the administration side of the store. Therefore, the files in the admin folder will handle any changes to its settings, the way the module is displayed in the administration, install/uninstalling the module, etc. Likewise, the way the module is displayed and how it works in the front end of the store will be handled by the files in the catalog folder.
The image above displays a skeleton of the directory structure that your module should follow. A good way to get started with your module is to duplicate the folder structure and create the files above. What will go in those files is determined by what your module is trying to accomplish, but the basic functionality is detailed in the sections below.
Admin module functionality
When a store owner uses your module, they will want to edit the module's configuration options in the admin in order to decide which layouts to display the module on, whether it is enabled or disabled, and any module specific options. As the module developer, you will need to create the admin page where the module may be edited and the configuration options added or adjusted.
All admin files are located in the admin/ folder. You will find four folders within the admin/ folder:
stephan
20-Oct-2017 EST
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