Updating Varbase to work with Composer 2.0

Step #1: Update composer to latest composer 1.0 by

composer self-update --1

Step #2: Update Varbase projectcomposer.josn file

Change the following:

"composer/installers": "~1.0",

"oomphinc/composer-installers-extender": "~1.0",

"cweagans/composer-patches": "~1.0",

"drupal/drupal-library-installer-plugin": "^0.3",

To:

"composer/installers": "~2.0",

"oomphinc/composer-installers-extender": "~2.0",

"cweagans/composer-patches": "~1.0",

Remove drupal/drupal-library-installer-plugin

Step #3: Update Varbase to 8.8.8 or 9.0.0-rc1 with Composer 1.0

cd /PATH_TO_THE_PROJECT

composer update -vvv

Repeat this composer update 2 or 3 times to make sure that their are no updates

Step #4: Update composer to latest composer 2.0 by

composer self-update --2

Step #5: Rebuild the autoloader for map of classes and namespaces

cd /PATH_TO_THE_PROJECT

rm -rf composer.lock bin/ vendor/ docroot/modules/contrib/ docroot/themes/contrib/ docroot/profiles/varbase/ docroot/libraries/

composer install -vvv

cd docroot/

drush cr

At this point the autoload and real autoload files + mapping should be changed.

Custom Composer plugins must have "composer-plugin-api": "^1.1 || ^2"

Make sure that the root composer.json file do not have invalid PSR-0 / PSR-4 . And the class configurations will not autoload anymore in optimized-autoloader mode, as per the warnings introduced in 1.10