Consider the form operation when locking

Thank you, @kfritsche!

One not really important nit:

+++ b/config/schema/content_lock.schema.yml
@@ -13,3 +13,24 @@ content_lock.settings:
\ No newline at end of file

We need to add a new line at the end of the file.

After thinking about this feature over again, I think that on the settings form we should disable the opposite list when checking form operations on one of the lists. I mean if a user selects a checkbox on the black list, then the options on the white list should be disabled and on form submit the white list should be saved empty. What do you think about this?

I agree to you proposal and would suggest to re-do it with 3 radio buttons (off / white list / black list) and only one time with the form ops checkboxes.

@kfritsche++ I like your idea better than mine :)

+++ b/config/schema/content_lock.schema.yml
@@ -13,3 +13,15 @@ content_lock.settings:
+    form_op_lock:
+    type: mapping
+    mapping:
+      mode:
...
+      values:

Unfortunately the schema is not entirely correct. We need one parent level for the entity type :).

We also have to consider #2911532-26: Lock on entity translation level instead on entity level - we have to add an update hook and create the column for the langcode, which we've missed in the other issue, and also add the column for the form operation.

Look great now. Thank you!

Lets assume your custom module's name is "custom_module".

1. Navigate to http://d8/admin/structure/display-modes/form and create a new form mode named "settings", which makes sense if it has different fields defined than the default or the edit form display mode - for this save the new form mode with different fields under http://d8/admin/structure/types/manage/article/form-display.

2. Then in custom_module.module you have to define the new form operation on the entity type:

function custom_module_entity_type_alter(&$entity_types) {
  $entity_types['node']
    ->setLinkTemplate('settings, '/node/{node}/settings')
    ->setFormClass('settings', 'Drupal\node\NodeForm');
}

3. In custom_module.links.task.yml create the link:

entity.node.settings:
  route_name: entity.node.settings
  base_route: entity.node.canonical
  title: 'Settings'

4. In custom_module.routing.yml add the route:

entity.node.settings:
  path: '/node/{node}/settings'
  defaults:
    _entity_form: 'node.settings'
    _title: 'Settings'
  options:
    _node_operation_route: TRUE

5. drush cr :)

What we've achieved now is that we have a new form display using its own form operation and it has edit access to different fields than the edit/default form mode. Now if we have two completely different form displays with no common fields the conflict module will be able to automatically merge the fields if two users concurrently saved both forms - the edit one and the settings one and therefore removes the need for locking the whole entity.

P.S. I hope that I've provided all the steps needed to create a new form operation and form using it, please don't blame me if I am missing something :).

I think you have to add a requirement to the route definition e.g.

requirements:
    _entity_access: 'node.update'

So that the route definition looks like this :

entity.node.settings:
  path: '/node/{node}/settings'
  defaults:
    _entity_form: 'node.settings'
    _title: 'Settings'
  options:
    _node_operation_route: TRUE
  requirements:
    _entity_access: 'node.update'