Magento 2: Run a uninstall script when module is uninstalled via command line?

Question

I am creating a module and I am progressing it. I am new to Magento 2 so there are a lot of things that I am not yet familiar too. As a module creator, I am curious how to run an uninstall script when someone uninstalled your module via command line.

I know I can execute the module uninstall command like this:

php bin/magento module:uninstall -r Vendor_Module

Answer 1

Magento Setup Uninstall script

The below page in the Magento DevDocs explains the process of module uninstallation. It explains the steps that are taken and one of those steps is running Uninstall scripts of the modules:

http://devdocs.magento.com/guides/v2.2/install-gde/install/cli/install-cli-uninstall-mods.html#instgde-cli-uninst-mod-uninst

6. If --remove-data is specified, removes the database schema and data defined in the module's Uninstall classes.

   For each specified module to uninstall, invokes the uninstall method in its Uninstall class. This class must inherit from Magento\Framework\Setup\UninstallInterface.

So this indicates for a module to run a script at uninstall, the module should be uninstalled using the --remove-data option, or shorthand -r. So if the users of your module do not use that option, the script won't run.

For a "Company MyModule" module, the script should be located at app/code/Company/MyModule/Setup/Uninstall.php or vendor/company/mymodule/Setup/Uninstall.php and must implement the \Magento\Framework\Setup\UninstallInterface interface. It could look like this:

namespace Company\MyModule\Setup;

use Magento\Framework\Setup\ModuleContextInterface;
use Magento\Framework\Setup\SchemaSetupInterface;
use Magento\Framework\Setup\UninstallInterface;

class Uninstall implements UninstallInterface
{
    public function uninstall(
        SchemaSetupInterface $setup,
        ModuleContextInterface $context
    ) {
        $setup->startSetup();
        // Uninstall schema and/or data...
        $setup->endSetup();
    }
}

---

Composer Package Uninstall event script

If your module is a composer package (residing in vendor/), then the Magento module uninstaller will run composer remove to remove the package files that were installed into the vendor dir.

Now, composer has a mechanism to run scripts on certain events, including package removal/uninstall. Unfortunately for module vendors, only scripts configured in the root composer.json will be ran. So if you have scripts configured like below in your root composer.json (root of your Magento project), then these will be triggered whenever a module will be uninstalled through the Magento bin/magento module:uninstall command:

{
    "scripts": {
        "pre-package-uninstall": "Company\\MyModule\\Setup\\Uninstall::composerUninstall",
        "post-package-uninstall": [
            "php -r \"copy('some-dir/some-file.php.backup', 'some-dir/some-file.php');\""
        ]
    }
}

https://getcomposer.org/doc/articles/scripts.md

Answer 2

run : php bin/magento module:uninstall -r Vendor_Module