Work on #1521.

islandora.links.menu.yml

@@ -11,3 +11,10 @@ system.islandora_settings:
   parent: system.admin_config_islandora
   route_name: system.islandora_settings 
   description: 'Confgure core Islandora settings'
+
+# Field to RDF property mappings
+system.islandora_rdf_mappings:
+  title: 'RDF field mappings'
+  parent: system.admin_reports
+  description: 'List of configured Drupal field to RDF property mappings.'
+  route_name: system.islandora_rdf_mappings

islandora.routing.yml

@@ -16,6 +16,15 @@ system.islandora_settings:
   requirements:
     _permission: 'administer site configuration'
 
+# RDF mappings report
+system.islandora_rdf_mappings:
+  path: '/admin/reports/islandora/rdf_mappings'
+  defaults:
+    _controller: '\Drupal\islandora\Controller\RdfMappingsReportController::main'
+    _title: 'Drupal field to RDF property mappings'
+  requirements:
+    _permission: 'administer site configuration'
+
 islandora.add_member_to_node_page:
   path: '/node/{node}/members/add'
   defaults:

src/Controller/RdfMappingsReportController.php

@@ -0,0 +1,73 @@
+<?php
+
+namespace Drupal\islandora\Controller;
+
+use Drupal\Core\Controller\ControllerBase;
+
+/**
+ * RDF mappings report controller.
+ */
+class RdfMappingsReportController extends ControllerBase {
+
+  /**
+   * Output the RDF mappings report.
+   *
+   * @return string
+   *   Markup of the tables.
+   */
+  public function main() {
+
+    $markup = '';
+    $entity_types = ['node', 'media'];
+
+    foreach ($entity_types as $entity_type) {
+      $bundles = \Drupal::service('entity_type.bundle.info')->getBundleInfo($entity_type);
+      foreach ($bundles as $name => $attr) {
+        $markup .= '<h3>' . $attr['label'] . ' (' . $entity_type . ')' . '</h3>';
+        $rdf_mappings = rdf_get_mapping($entity_type, $name);
+        $fields = \Drupal::entityManager()->getFieldDefinitions($entity_type, $name);
+        $mappings_table_rows = [];
+        foreach ($fields as $field_name => $field_object) {
+          $field_mappings = $rdf_mappings->getPreparedFieldMapping($field_name);
+          if (array_key_exists('properties', $field_mappings)) {
+            $mappings_table_rows[] = [$field_object->getLabel() . ' (' . $field_name . ')', $field_mappings['properties'][0]];
+          }
+        }
+
+        $mappings_header = [t('Drupal field'), t('RDF property')];
+
+        if (count($mappings_table_rows) == 0) {
+          $mappings_header = [];
+          $mappings_table_rows[] = [t('No RDF mappings configured for @bundle.', ['@bundle' => $attr['label']])];
+        }
+
+        $mappings_table = [
+          '#theme' => 'table',
+          '#header' => $mappings_header,
+          '#rows' => $mappings_table_rows,
+        ];
+        $mappings_table_markup = \Drupal::service('renderer')->render($mappings_table);
+        $markup .= $mappings_table_markup;
+      }
+    }
+
+    $markup .= '<h3>RDF namespaces</h3>';
+    $namespaces = rdf_get_namespaces();
+    $namespaces_table_rows = [];
+    foreach ($namespaces as $alias => $namespace_uri) {
+      $namespaces_table_rows[] = [$alias, $namespace_uri];
+    }
+    $namespaces_table_header = [t('Namespace alias'), t('Namespace URI')];
+    $namespaces_table = [
+      '#theme' => 'table',
+      '#header' => $namespaces_table_header,
+      '#rows' => $namespaces_table_rows,
+    ];
+    $namespaces_table_markup = \Drupal::service('renderer')->render($namespaces_table);
+
+    $markup .= $namespaces_table_markup;
+
+    return ['#markup' => $markup];
+  }
+
+}