Issue
When pulling the site into Cloud IDE with `acli pull`, you get the following error - `Unable to install Drupal dependencies via Composer. The "composer/installers" plugin was skipped because it requires a Plugin API version ("^1.0") that does not match your Composer installation ("2.0.0"). You may need to run composer update with the "--no-plugins"
option.`
Or similar error for any other plugins.
Resolution
This issue is occurring due to the fact that Cloud IDE now defaults to Composer 2 (since the 17th of January as you can read in https://docs.acquia.com/ide/release-notes/#cloud-ide-january-17-2021).
There are several options to fix this :
- Update your apps and Composer dependencies so they are all compatible with Composer 2 (we recommend you to investigate this option in order to be ready when Composer 1 will not be supported anymore, even if we do not have an ETA on this yet)
- Specifically invoke Composer 1 for Composer operations.
If you do want to specifically invoke Composer 1, it will then mean to first use the following command to avoid using Composer 2 when running acli pull, switch to running an `acli pull --no-scripts` and then to manually refresh the source environment into the IDE running `composer1 install` to pull vendor dependencies.