mage2_fix_is12655

Standalone fix for ISSUE-12655: Checkout/Cart visit results in error (500) after update 2.2.1 -> 2.2.2

Install

$ cd ${DIR_MAGE_ROOT}
$ composer require flancer32/mage2_fix_is12655
$ bin/magento module:enable Flancer32_FixIs12655
$ bin/magento setup:upgrade
$ bin/magento setup:di:compile
$ bin/magento setup:static-content:deploy
$ bin/magento cache:clean
$ <set filesystem permissions to your files>

Uninstall

You need an authentication keys for https://repo.magento.com/ to uninstall any Magento 2 module. Go to your Magento account, section (My Profile / Marketplace / Access Keys) and generate pair of keys to connect to Magento 2 repository. Then place composer authentication file auth.json besides your composer.json as described here and put your authentication keys for https://repo.magento.com/ into the authentication file:

{
  "http-basic": {
    "repo.magento.com": {
      "username": "...",
      "password": "..."
    }
  }
}

Then run these commands to completely uninstall Flancer32_FixIs12655 module:

$ cd ${DIR_MAGE_ROOT}   
$ bin/magento module:uninstall Flancer32_FixIs12655
$ bin/magento setup:upgrade
$ bin/magento setup:di:compile
$ bin/magento setup:static-content:deploy
$ bin/magento cache:clean

Be patient, uninstall process (bin/magento module:uninstall ...) takes about 2-4 minutes. Remove auth.json file at the end:

$ rm ./auth.json