Creating a render preprocessor

Render preprocessors are defined as Drupal RjsfRenderPreprocess plugins in modules. To create your own preprocessor plugin:

1. Navigate to the custom module that will contain your plugin
2. Open or create custom_module/src/Plugin/Rjsf/RenderPreprocess
3. Create a new class ExamplePlugin.php
4. Extend RenderPreprocessPluginBase
5. Populate the annotation and preprocess() method

Example

Additional examples can be found in the RJSF module.

<?php

namespace Drupal\custom_module\Plugin\Rjsf\RenderPreprocess;

/**
 * @RjsfRenderPreprocess(
 *  id = "example_preprocess",
 *  label = @Translation("Example preprocess"),
 * )
 */
class ExamplePlugin extends RenderPreprocessPluginBase {

  public function preprocess($value, array $vars = [], array $schema = [], array $uiSchema = []) {
   // Do preprocessing logic here
   $processed = '';

    return $processed;
  }

}

Arguments

value

This will contain the value of the property targeted in the renderPreprocess part of a schema. Currently preprocessors do not have access to the complete form data but that may change in the future.

vars

Any vars defined with the plugin definition in a renderPreprocess.

schema

The full schema definition.

uiSchema

The full uiSchema defintion.