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There are six main aspects of PrestaShop's Module API which received a significant overhaul for version 1.5: dynamic hooks, evolution of the override system, new file-tree and operations, multishop multistore feature, Addons webservice, and the update system. We will explore these one by one.
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/config.xml: Automatically created by PrestaShop when the module is loaded./mymodule.php/mymodule.jpg: Logo file, 16*16 pixels. For versions of PrestaShop up to v1.4./mymodule.png: Logo file, 32*32 pixels. For PrestaShop 1.5 and later./controllers//controllers/front/myfile.php: As explained above./upgrade/: Upgrade files. See Update System./translations//translations/fr.php: French language file, created automatically when you start translating the module in your back-office./translations/de.php: German (deutsch) language file, created automatically when you start translating the module in your back-office./translations/...: ...and so on.../views//views/css/: For CSS files./views/js/: For JavaScript files./views/templates/admin/views/templates/admin/folder_name: For template files used by the module's admin controllers. (e.g. "sample_data" for the "SampleData" admin controller)/views/templates/front/: For template files used by the module's controllers./views/templates/hooks/: For template files directly used by the module. For backward compatibility purposes, this type of files can also be placed in the root folder of the module.
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Multistore Feature
One of the major features of version 1.5 is the multishop multistore feature, which enable shop owners to manage more than one shop with a single installation of PrestaShop. However, this has deep implications in the code of PrestaShop, and while all modules written for v1.4 should work as-is with v1.5, most will not work as expected in the multishop multistore context.
If your 1.4 module only stores its data using Configuration::get and Configuration::updateValue, it should have no problem working with multiple shops.
On the other hands, if the module stores its data within its own database tables, you will have to update these tables: add a id_shop row in the table where you will store the shop's ID when saving data.
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install-1.8.0.phpinstall-1.8.1.phpinstall-1.8.2.phpinstall-1.8.3.php
If you are updating from v1version 1.8.1 to v1version 1.8.3 of the module, PrestaShop will only load the two last files, install-1.8.2.php and install-1.8.3.php.
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