Support Check Mode

[simensen]

The uri module does not support Check Mode. This means any playbook run in Check Mode will fail if Composer has not been installed previously.

The error looks like this:

The task includes an option with an undefined variable. The error was: 'dict object' has no attribute 'content'. 'dict object' has no attribute 'content'

The object in question is composer_installer_signature. It is empty/undefined since the "Get Composer installer signature." task isn't executed in Check Mode.

By adding check_mode: false to the uri call, this will signal that it should run in check mode to satisfy the composer_installer_signature dependency for the "Download Composer installer." task.

https://docs.ansible.com/ansible/latest/collections/ansible/builtin/uri_module.html#attribute-check_mode

[simensen]

Also, more information on this can be found here:

https://docs.ansible.com/ansible/latest/playbook_guide/playbooks_checkmode.html#enforcing-or-preventing-check-mode-on-tasks

[simensen]

My bad for the multiple comments. I think this will be the last for a while. :)

For some context, our team has a CI pipeline for its playbooks. One of the stages checks to ensure that the playbook can be run in Check Mode against a snapshot of a known current state. When we introduced this role, that CI process failed, even though we could run it normally just fine. It will continue to fail until the known current state snapshot already has Composer installed.