I have an 8.9.19 installation that I would like to move over to use composer.
What's the best way to migrate the installation to use composer upgrades? Manual installations are becoming a real pain.
Drupal Answers is a question and answer site for Drupal developers and administrators. It only takes a minute to sign up.Sign up to join this community
The most common way to 'flip' a project from not having Composer managed dependencies to being managed by Composer is to use the Composerize project: https://github.com/grasmash/composerize-drupal
I wouldn't say there is a most common way. Drupal is by default now composer ready since it introduced two project templates of its own. The answer depends on the specific requirements. If you want to switch between different composer templates it's also no problem to start a new composer project, require the packages of the installed modules and then move database and files directory from the old to the new installation.