Improve multi-value and checkbox support for BPMN based modellers

Moving this to ECA as the config field preparation is being done in the base BPMN modeller that belongs to ECA.

@mxh the stacktrace looks like is not a version that I can reproduce this with. The given line numbers are within comments and that doesn't seem to be right. Maybe you could post the stacktrace without markup?

Also, could you provide more details about version of used components, please? Because I can't reproduce the problem. Checkboxes should be supported and I see plugins that use it, but I still don't get the error message.

Here is the stack trace from the logs:

Warning: Array to string conversion in Drupal\eca_modeller_bpmn\ModellerBpmnBase->prepareConfigFields() (line 766 of [...]/web/modules/contrib/eca/modules/modeller_bpmn/src/ModellerBpmnBase.php)
#0 [...]/web/core/includes/bootstrap.inc(158): _drupal_error_handler_real(2, 'Array to string...', '/Users/mxh/proj...', 766)
#1 [...]/web/modules/contrib/eca/modules/modeller_bpmn/src/ModellerBpmnBase.php(766): _drupal_error_handler(2, 'Array to string...', '/Users/mxh/proj...', 766)
#2 [...]/web/modules/contrib/eca/modules/modeller_bpmn/src/ModellerBpmnBase.php(591): Drupal\eca_modeller_bpmn\ModellerBpmnBase->prepareConfigFields(Array)
#3 [...]/web/modules/contrib/eca/modules/modeller_bpmn/src/ModellerBpmnBase.php(547): Drupal\eca_modeller_bpmn\ModellerBpmnBase->properties(Object(Drupal\oc_eca\Plugin\Action\TokenGetFieldNames), 'action', 'bpmn:Task', Array)
#4 [...]/web/modules/contrib/bpmn_io/src/Plugin/ECA/Modeller/BpmnIo.php(76): Drupal\eca_modeller_bpmn\ModellerBpmnBase->getTemplates()
#5 [...]/web/modules/contrib/bpmn_io/src/Controller/BpmnIo.php(61): Drupal\bpmn_io\Plugin\ECA\Modeller\BpmnIo->edit()
#6 [internal function]: Drupal\bpmn_io\Controller\BpmnIo->add()
#7 [...]/web/core/lib/Drupal/Core/EventSubscriber/EarlyRenderingControllerWrapperSubscriber.php(123): call_user_func_array(Array, Array)
#8 [...]/web/core/lib/Drupal/Core/Render/Renderer.php(580): Drupal\Core\EventSubscriber\EarlyRenderingControllerWrapperSubscriber->Drupal\Core\EventSubscriber\{closure}()
#9 [...]/web/core/lib/Drupal/Core/EventSubscriber/EarlyRenderingControllerWrapperSubscriber.php(124): Drupal\Core\Render\Renderer->executeInRenderContext(Object(Drupal\Core\Render\RenderContext), Object(Closure))
#10 [...]/web/core/lib/Drupal/Core/EventSubscriber/EarlyRenderingControllerWrapperSubscriber.php(97): Drupal\Core\EventSubscriber\EarlyRenderingControllerWrapperSubscriber->wrapControllerExecutionInRenderContext(Array, Array)
#11 [...]/vendor/symfony/http-kernel/HttpKernel.php(163): Drupal\Core\EventSubscriber\EarlyRenderingControllerWrapperSubscriber->Drupal\Core\EventSubscriber\{closure}()
#12 [...]/vendor/symfony/http-kernel/HttpKernel.php(74): Symfony\Component\HttpKernel\HttpKernel->handleRaw(Object(Symfony\Component\HttpFoundation\Request), 1)
#13 [...]/web/core/lib/Drupal/Core/StackMiddleware/Session.php(58): Symfony\Component\HttpKernel\HttpKernel->handle(Object(Symfony\Component\HttpFoundation\Request), 1, true)
#14 [...]/web/core/lib/Drupal/Core/StackMiddleware/KernelPreHandle.php(48): Drupal\Core\StackMiddleware\Session->handle(Object(Symfony\Component\HttpFoundation\Request), 1, true)
#15 [...]/web/core/modules/page_cache/src/StackMiddleware/PageCache.php(106): Drupal\Core\StackMiddleware\KernelPreHandle->handle(Object(Symfony\Component\HttpFoundation\Request), 1, true)
#16 [...]/web/core/modules/page_cache/src/StackMiddleware/PageCache.php(85): Drupal\page_cache\StackMiddleware\PageCache->pass(Object(Symfony\Component\HttpFoundation\Request), 1, true)
#17 [...]/web/core/lib/Drupal/Core/StackMiddleware/ReverseProxyMiddleware.php(48): Drupal\page_cache\StackMiddleware\PageCache->handle(Object(Symfony\Component\HttpFoundation\Request), 1, true)
#18 [...]/web/core/lib/Drupal/Core/StackMiddleware/NegotiationMiddleware.php(51): Drupal\Core\StackMiddleware\ReverseProxyMiddleware->handle(Object(Symfony\Component\HttpFoundation\Request), 1, true)
#19 [...]/web/core/lib/Drupal/Core/StackMiddleware/StackedHttpKernel.php(51): Drupal\Core\StackMiddleware\NegotiationMiddleware->handle(Object(Symfony\Component\HttpFoundation\Request), 1, true)
#20 [...]/web/core/lib/Drupal/Core/DrupalKernel.php(681): Drupal\Core\StackMiddleware\StackedHttpKernel->handle(Object(Symfony\Component\HttpFoundation\Request), 1, true)
#21 [...]/web/index.php(19): Drupal\Core\DrupalKernel->handle(Object(Symfony\Component\HttpFoundation\Request))
#22 {main}
.

I'm using ECA 1.1.1 and BPMN io 1.1.1. The affected action is a custom implementation, which is using a checkboxes field element. Without a checkboxes element the error is gone.

We do currently support checkboxes similarly to radios and select fields:

          case 'checkboxes':
          case 'radios':
          case 'select':
            $fields[] = $this->optionsField($key, $label, $weight, $description, $definition['#options'], (string) $value, $definition['#required'] ?? FALSE);
            continue 2;

The first 2 have not yet been implemented by ECA modules, only the select field type. But the way it's being implemented is that we expect a string value, which works just fine for select fields, as long as they don't allow multiple values to be selected. In that case, the value would be an array as it is with checkboxes. Radios though provide multiple options but only a single value, that should be fine.

So, where this falls short is for checkboxes and select fields with multiple set to true. For the bpmn modellers we know so far, we would have to convert each option into a drop down list in these 2 cases.

As per #5 this needs to be implemented for select field with multi-value support and for checkboxes, that always accept multiple value.

We need to investigate, if and how such widgets can be supported in bpmn_io and camunda modellers.

I'm going to look into this, since bpmn_io has added support for more field types. Maybe there is something for this use case, and there is certainly support for checkboxes now, so that we can probably get rid of the yes|no dropdown as well.

Bringing my secondary issue from eca commerce → over.

@jurgenhaas Could you provide me with a bit more information?

In my case, I'm using eca_commerce to trigger when an order is completed. My model then adds the user to the pre-configured paid member role and removes them from two lower level pre-configured roles. I'm assuming the roles options are the checkboxes causing the problem.

What's the best workaround for this use case?

You say "As a workaround, for now the eca commerce conditions should fall back to single value checkbox for now" (from my previous issue).

Does this mean it will work if I split the 3 changes into separate modules, or do you mean it will only work with fields that have a single boolean checkbox option?

There is nothing you can do about this as a user. That one condition mentioned in 🐛 Undefined array key "parent_entity_type" CommerceDeriver.php:61 Fixed needs to be fixed with the mentioned workaround in that other issue.