Add the ability to use State API instead of Configuration API to store checklist progress

I agree. We'll need an upgrade path, of course. I won't be able to get to this right away. Patches welcome.

I would take approach #2. The State API should serialize the array for you. The storage system should be essentially swappable in \Drupal\checklistapi\ChecklistapiChecklist::saveProgress(). Thanks!

chr.fritch very nice!

+1 to this patch.

The declaration of the PROGRESS_CONFIG_KEY constant is obsolete after this patch but it can't actually be removed because then the update would break— maybe it would make sense to hard-code the constant value in the update hook just so the constant could be cleaned up?

I would suggest that the $config variable be changed to $state or $progress for easy comprehension of the code but that's also minor / not really the role of this patch.

Hi Travis, have you had a chance to review this?

I came here to file the same issue, and am glad to see it filed, encouraged, and with a patch! As far as upgrade path i was wondering if it wouldn't be too much burden for Checklist API to support *both* config and states checklists (for instance SEO Checklist using config makes sense as its one set of tasks to do across dev and live— but this patch already has the upgrade path!

Thanks, all! @mlncn, I like the idea of supporting both config and state for progress storage. I'll make it a setting in hook_checklistapi_checklist_info() so module authors can choose which they want and developers can override it with hook_checklistapi_checklist_info_alter(). I'll make it optional for backward compatibility and default it to config. Let me see what I can whip up.

Let's see what the tests say about this.

Oops. Accidentally used a PHP 7.1 only feature.

All right, there you go! Module maintainers can now choose their storage backend by setting the "#storage" value in their checklist definition. Allowed values are "config" and "state". Default is "config". Developers can override a checklist's storage setting using hook_checklistapi_checklist_info_alter() as in the below example:

function example_checklistapi_checklist_info_alter(array &$definitions) {
  $definitions['seo_checklist']['#storage'] = 'state';
}

Checklist API Example module contains an example of moving saved progress from one backend to the other in an update hook:

function checklistapiexample_update_8101() {
  $checklist_id = 'example_checklist';

  // Get saved progress from old config storage.
  /** @var \Drupal\checklistapi\Storage\ConfigStorage $old_config_storage */
  $old_config_storage = \Drupal::service('checklistapi_storage.config');
  $saved_progress = $old_config_storage->setChecklistId($checklist_id)
    ->getSavedProgress();

  // Copy saved progress to new state storage.
  /** @var \Drupal\checklistapi\Storage\StateStorage $new_state_storage */
  $new_state_storage = \Drupal::service('checklistapi_storage.state');
  $new_state_storage->setChecklistId($checklist_id)
    ->setSavedProgress($saved_progress);

  // Delete old config storage.
  $old_config_storage->deleteSavedProgress();
}

I'll cut a release with the new feature soon. Feedback welcome. Thanks for the suggestion and the help!