Give it a first try to get data from European data Portal endpoint.

modules/dcat_demo/tests/src/Functional/DcatDemoTest.php

@@ -0,0 +1,63 @@
+<?php
+
+namespace Drupal\Tests\dcat_demo\Functional;
+
+use Drupal\Tests\BrowserTestBase;
+use Drupal\Tests\rdf_entity\Traits\RdfDatabaseConnectionTrait;
+
+/**
+ * Makes a demo as functional test.
+ */
+class DcatDemoTest extends BrowserTestBase {
+
+  use RdfDatabaseConnectionTrait {
+    getSparqlConnectionInfo as getSparqlConnectionInfoTrait;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  protected static $modules = [
+    'dcat_demo',
+  ];
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function setUp() {
+    $this->setUpSparql();
+    parent::setUp();
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function test() {
+    $query = <<<Query
+SELECT DISTINCT ?Concept
+WHERE {
+  [] a ?Concept
+}
+LIMIT 100
+Query;
+    $response = $this->sparql->query($query);
+    print $response->count();
+    foreach ($response as $row) {
+      print_r($row->Concept->getUri() . "\n");
+    }
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function getSparqlConnectionInfo(): array {
+    if (!isset($this->sparqlConnectionInfo)) {
+      $this->getSparqlConnectionInfoTrait();
+      $this->sparqlConnectionInfo['host'] = 'data.europa.eu';
+      $this->sparqlConnectionInfo['port'] = 80;
+      $this->sparqlConnectionInfo['database'] = 'euodp/sparqlep';
+    }
+    return $this->sparqlConnectionInfo;
+  }
+
+}