StyleSerializerTest.php

<?php

namespace Drupal\Tests\rest\Functional\Views;

use Drupal\Component\Serialization\Json;
use Drupal\Core\Cache\Cache;
use Drupal\Core\EventSubscriber\MainContentViewSubscriber;
use Drupal\Core\Field\FieldStorageDefinitionInterface;
use Drupal\entity_test\Entity\EntityTest;
use Drupal\field\Entity\FieldConfig;
use Drupal\field\Entity\FieldStorageConfig;
use Drupal\language\Entity\ConfigurableLanguage;
use Drupal\Tests\system\Functional\Cache\AssertPageCacheContextsAndTagsTrait;
use Drupal\Tests\views\Functional\ViewTestBase;
use Drupal\views\Entity\View;
use Drupal\views\Plugin\views\display\DisplayPluginBase;
use Drupal\views\Views;
use Symfony\Component\HttpFoundation\Request;

/**
 * Tests the serializer style plugin.
 *
 * @group rest
 * @see \Drupal\rest\Plugin\views\display\RestExport
 * @see \Drupal\rest\Plugin\views\style\Serializer
 * @see \Drupal\rest\Plugin\views\row\DataEntityRow
 * @see \Drupal\rest\Plugin\views\row\DataFieldRow
 */
class StyleSerializerTest extends ViewTestBase {
    use AssertPageCacheContextsAndTagsTrait;
    
    /**
     * Modules to install.
     *
     * @var array
     */
    protected static $modules = [
        'views_ui',
        'entity_test',
        'rest_test_views',
        'node',
        'text',
        'field',
        'language',
        'basic_auth',
    ];
    
    /**
     * {@inheritdoc}
     */
    protected $defaultTheme = 'stark';
    
    /**
     * Views used by this test.
     *
     * @var array
     */
    public static $testViews = [
        'test_serializer_display_field',
        'test_serializer_display_entity',
        'test_serializer_display_entity_translated',
        'test_serializer_node_display_field',
        'test_serializer_node_exposed_filter',
        'test_serializer_shared_path',
    ];
    
    /**
     * A user with administrative privileges to look at test entity and configure views.
     */
    protected $adminUser;
    
    /**
     * The renderer.
     *
     * @var \Drupal\Core\Render\RendererInterface
     */
    protected $renderer;
    
    /**
     * {@inheritdoc}
     */
    protected function setUp($import_test_views = TRUE, $modules = [
        'rest_test_views',
    ]) : void {
        parent::setUp($import_test_views, $modules);
        $this->adminUser = $this->drupalCreateUser([
            'administer views',
            'administer entity_test content',
            'access user profiles',
            'view test entity',
        ]);
        // Save some entity_test entities.
        for ($i = 1; $i <= 10; $i++) {
            EntityTest::create([
                'name' => 'test_' . $i,
                'user_id' => $this->adminUser
                    ->id(),
            ])
                ->save();
        }
        $this->enableViewsTestModule();
        $this->renderer = \Drupal::service('renderer');
    }
    
    /**
     * Checks that the auth options restricts access to a REST views display.
     */
    public function testRestViewsAuthentication() {
        // Assume the view is hidden behind a permission.
        $this->drupalGet('test/serialize/auth_with_perm', [
            'query' => [
                '_format' => 'json',
            ],
        ]);
        $this->assertSession()
            ->statusCodeEquals(401);
        // Not even logging in would make it possible to see the view, because then
        // we are denied based on authentication method (cookie).
        $this->drupalLogin($this->adminUser);
        $this->drupalGet('test/serialize/auth_with_perm', [
            'query' => [
                '_format' => 'json',
            ],
        ]);
        $this->assertSession()
            ->statusCodeEquals(403);
        $this->drupalLogout();
        // But if we use the basic auth authentication strategy, we should be able
        // to see the page.
        $url = $this->buildUrl('test/serialize/auth_with_perm');
        $response = \Drupal::httpClient()->get($url, [
            'auth' => [
                $this->adminUser
                    ->getAccountName(),
                $this->adminUser->pass_raw,
            ],
            'query' => [
                '_format' => 'json',
            ],
        ]);
        // Ensure that any changes to variables in the other thread are picked up.
        $this->refreshVariables();
        $this->assertSession()
            ->statusCodeEquals(200);
    }
    
    /**
     * Checks the behavior of the Serializer callback paths and row plugins.
     */
    public function testSerializerResponses() {
        // Test the serialize callback.
        $view = Views::getView('test_serializer_display_field');
        $view->initDisplay();
        $this->executeView($view);
        $actual_json = $this->drupalGet('test/serialize/field', [
            'query' => [
                '_format' => 'json',
            ],
        ]);
        $this->assertSession()
            ->statusCodeEquals(200);
        $this->assertCacheTags($view->getCacheTags());
        $this->assertCacheContexts([
            'languages:language_interface',
            'theme',
            'request_format',
        ]);
        // @todo Due to https://www.drupal.org/node/2352009 we can't yet test the
        // propagation of cache max-age.
        // Test the http Content-type.
        $headers = $this->getSession()
            ->getResponseHeaders();
        $this->assertSame([
            'application/json',
        ], $headers['Content-Type']);
        $expected = [];
        foreach ($view->result as $row) {
            $expected_row = [];
            foreach ($view->field as $id => $field) {
                $expected_row[$id] = $field->render($row);
            }
            $expected[] = $expected_row;
        }
        $this->assertSame(json_encode($expected), $actual_json, 'The expected JSON output was found.');
        // Test that the rendered output and the preview output are the same.
        $view->destroy();
        $view->setDisplay('rest_export_1');
        // Mock the request content type by setting it on the display handler.
        $view->display_handler
            ->setContentType('json');
        $output = $view->preview();
        $this->assertSame((string) $this->renderer
            ->renderRoot($output), $actual_json, 'The expected JSON preview output was found.');
        // Test a 403 callback.
        $this->drupalGet('test/serialize/denied', [
            'query' => [
                '_format' => 'json',
            ],
        ]);
        $this->assertSession()
            ->statusCodeEquals(403);
        // Test the entity rows.
        $view = Views::getView('test_serializer_display_entity');
        $view->initDisplay();
        $this->executeView($view);
        // Get the serializer service.
        $serializer = $this->container
            ->get('serializer');
        $entities = [];
        foreach ($view->result as $row) {
            $entities[] = $row->_entity;
        }
        $expected = $serializer->serialize($entities, 'json');
        $actual_json = $this->drupalGet('test/serialize/entity', [
            'query' => [
                '_format' => 'json',
            ],
        ]);
        $this->assertSession()
            ->statusCodeEquals(200);
        $this->assertSame($expected, $actual_json, 'The expected JSON output was found.');
        $expected_cache_tags = $view->getCacheTags();
        $expected_cache_tags[] = 'entity_test_list';
        
        /** @var \Drupal\Core\Entity\EntityInterface $entity */
        foreach ($entities as $entity) {
            $expected_cache_tags = Cache::mergeTags($expected_cache_tags, $entity->getCacheTags());
        }
        $this->assertCacheTags($expected_cache_tags);
        $this->assertCacheContexts([
            'languages:language_interface',
            'theme',
            'entity_test_view_grants',
            'request_format',
        ]);
        // Change the format to xml.
        $view->setDisplay('rest_export_1');
        $view->getDisplay()
            ->setOption('style', [
            'type' => 'serializer',
            'options' => [
                'uses_fields' => FALSE,
                'formats' => [
                    'xml' => 'xml',
                ],
            ],
        ]);
        $view->save();
        $expected = $serializer->serialize($entities, 'xml');
        $actual_xml = $this->drupalGet('test/serialize/entity', [
            'query' => [
                '_format' => 'xml',
            ],
        ]);
        $this->assertSame(trim($expected), $actual_xml);
        $this->assertCacheContexts([
            'languages:language_interface',
            'theme',
            'entity_test_view_grants',
            'request_format',
        ]);
        // Allow multiple formats.
        $view->setDisplay('rest_export_1');
        $view->getDisplay()
            ->setOption('style', [
            'type' => 'serializer',
            'options' => [
                'uses_fields' => FALSE,
                'formats' => [
                    'xml' => 'xml',
                    'json' => 'json',
                ],
            ],
        ]);
        $view->save();
        $expected = $serializer->serialize($entities, 'json');
        $actual_json = $this->drupalGet('test/serialize/entity', [
            'query' => [
                '_format' => 'json',
            ],
        ]);
        $this->assertSame($expected, $actual_json, 'The expected JSON output was found.');
        $expected = $serializer->serialize($entities, 'xml');
        $actual_xml = $this->drupalGet('test/serialize/entity', [
            'query' => [
                '_format' => 'xml',
            ],
        ]);
        $this->assertSame(trim($expected), $actual_xml);
    }
    
    /**
     * Verifies REST export views work on the same path as a page display.
     */
    public function testSharedPagePath() {
        // Test with no format as well as html explicitly.
        $this->drupalGet('test/serialize/shared');
        $this->assertSession()
            ->statusCodeEquals(200);
        $this->assertSession()
            ->responseHeaderEquals('content-type', 'text/html; charset=UTF-8');
        $this->drupalGet('test/serialize/shared', [
            'query' => [
                '_format' => 'html',
            ],
        ]);
        $this->assertSession()
            ->statusCodeEquals(200);
        $this->assertSession()
            ->responseHeaderEquals('content-type', 'text/html; charset=UTF-8');
        $this->drupalGet('test/serialize/shared', [
            'query' => [
                '_format' => 'json',
            ],
        ]);
        $this->assertSession()
            ->statusCodeEquals(200);
        $this->assertSession()
            ->responseHeaderEquals('content-type', 'application/json');
        $this->drupalGet('test/serialize/shared', [
            'query' => [
                '_format' => 'xml',
            ],
        ]);
        $this->assertSession()
            ->statusCodeEquals(200);
        $this->assertSession()
            ->responseHeaderEquals('content-type', 'text/xml; charset=UTF-8');
    }
    
    /**
     * Verifies site maintenance mode functionality.
     */
    public function testSiteMaintenance() {
        $view = Views::getView('test_serializer_display_field');
        $view->initDisplay();
        $this->executeView($view);
        // Set the site to maintenance mode.
        $this->container
            ->get('state')
            ->set('system.maintenance_mode', TRUE);
        $this->drupalGet('test/serialize/entity', [
            'query' => [
                '_format' => 'json',
            ],
        ]);
        // Verify that the endpoint is unavailable for anonymous users.
        $this->assertSession()
            ->statusCodeEquals(503);
    }
    
    /**
     * Sets up a request on the request stack with a specified format.
     *
     * @param string $format
     *   The new request format.
     */
    protected function addRequestWithFormat($format) {
        $request = \Drupal::request();
        $request = clone $request;
        $request->setRequestFormat($format);
        \Drupal::requestStack()->push($request);
    }
    
    /**
     * Tests REST export with views render caching enabled.
     */
    public function testRestRenderCaching() {
        $this->drupalLogin($this->adminUser);
        
        /** @var \Drupal\Core\Render\RenderCacheInterface $render_cache */
        $render_cache = \Drupal::service('render_cache');
        // Enable render caching for the views.
        
        /** @var \Drupal\views\ViewEntityInterface $storage */
        $storage = View::load('test_serializer_display_entity');
        $options =& $storage->getDisplay('default');
        $options['display_options']['cache'] = [
            'type' => 'tag',
        ];
        $storage->save();
        $original = DisplayPluginBase::buildBasicRenderable('test_serializer_display_entity', 'rest_export_1');
        // Ensure that there is no corresponding render cache item yet.
        $original['#cache'] += [
            'contexts' => [],
        ];
        $original['#cache']['contexts'] = Cache::mergeContexts($original['#cache']['contexts'], $this->container
            ->getParameter('renderer.config')['required_cache_contexts']);
        $cache_tags = [
            'config:views.view.test_serializer_display_entity',
            'entity_test:1',
            'entity_test:10',
            'entity_test:2',
            'entity_test:3',
            'entity_test:4',
            'entity_test:5',
            'entity_test:6',
            'entity_test:7',
            'entity_test:8',
            'entity_test:9',
            'entity_test_list',
        ];
        $cache_contexts = [
            'entity_test_view_grants',
            'languages:language_interface',
            'theme',
            'request_format',
        ];
        $this->assertFalse($render_cache->get($original));
        // Request the page, once in XML and once in JSON to ensure that the caching
        // varies by it.
        $result1 = Json::decode($this->drupalGet('test/serialize/entity', [
            'query' => [
                '_format' => 'json',
            ],
        ]));
        $this->addRequestWithFormat('json');
        $this->assertSession()
            ->responseHeaderEquals('content-type', 'application/json');
        $this->assertCacheContexts($cache_contexts);
        $this->assertCacheTags($cache_tags);
        $this->assertNotEmpty($render_cache->get($original));
        $result_xml = $this->drupalGet('test/serialize/entity', [
            'query' => [
                '_format' => 'xml',
            ],
        ]);
        $this->addRequestWithFormat('xml');
        $this->assertSession()
            ->responseHeaderEquals('content-type', 'text/xml; charset=UTF-8');
        $this->assertCacheContexts($cache_contexts);
        $this->assertCacheTags($cache_tags);
        $this->assertNotEmpty($render_cache->get($original));
        // Ensure that the XML output is different from the JSON one.
        $this->assertNotEquals($result1, $result_xml);
        // Ensure that the cached page works.
        $result2 = Json::decode($this->drupalGet('test/serialize/entity', [
            'query' => [
                '_format' => 'json',
            ],
        ]));
        $this->addRequestWithFormat('json');
        $this->assertSession()
            ->responseHeaderEquals('content-type', 'application/json');
        $this->assertEquals($result1, $result2);
        $this->assertCacheContexts($cache_contexts);
        $this->assertCacheTags($cache_tags);
        $this->assertNotEmpty($render_cache->get($original));
        // Create a new entity and ensure that the cache tags are taken over.
        EntityTest::create([
            'name' => 'test_11',
            'user_id' => $this->adminUser
                ->id(),
        ])
            ->save();
        $result3 = Json::decode($this->drupalGet('test/serialize/entity', [
            'query' => [
                '_format' => 'json',
            ],
        ]));
        $this->addRequestWithFormat('json');
        $this->assertSession()
            ->responseHeaderEquals('content-type', 'application/json');
        $this->assertNotEquals($result2, $result3);
        // Add the new entity cache tag and remove the first one, because we just
        // show 10 items in total.
        $cache_tags[] = 'entity_test:11';
        unset($cache_tags[array_search('entity_test:1', $cache_tags)]);
        $this->assertCacheContexts($cache_contexts);
        $this->assertCacheTags($cache_tags);
        $this->assertNotEmpty($render_cache->get($original));
    }
    
    /**
     * Tests the response format configuration.
     */
    public function testResponseFormatConfiguration() {
        $this->drupalLogin($this->adminUser);
        $style_options = 'admin/structure/views/nojs/display/test_serializer_display_field/rest_export_1/style_options';
        // Ensure a request with no format returns 406 Not Acceptable.
        $this->drupalGet('test/serialize/field');
        $this->assertSession()
            ->responseHeaderEquals('content-type', 'text/html; charset=UTF-8');
        $this->assertSession()
            ->statusCodeEquals(406);
        // Select only 'xml' as an accepted format.
        $this->drupalGet($style_options);
        $this->submitForm([
            'style_options[formats][xml]' => 'xml',
        ], 'Apply');
        $this->submitForm([], 'Save');
        // Ensure a request for JSON returns 406 Not Acceptable.
        $this->drupalGet('test/serialize/field', [
            'query' => [
                '_format' => 'json',
            ],
        ]);
        $this->assertSession()
            ->responseHeaderEquals('content-type', 'application/json');
        $this->assertSession()
            ->statusCodeEquals(406);
        // Ensure a request for XML returns 200 OK.
        $this->drupalGet('test/serialize/field', [
            'query' => [
                '_format' => 'xml',
            ],
        ]);
        $this->assertSession()
            ->responseHeaderEquals('content-type', 'text/xml; charset=UTF-8');
        $this->assertSession()
            ->statusCodeEquals(200);
        // Add 'json' as an accepted format, so we have multiple.
        $this->drupalGet($style_options);
        $this->submitForm([
            'style_options[formats][json]' => 'json',
        ], 'Apply');
        $this->submitForm([], 'Save');
        // Should return a 406. Emulates a sample Firefox header.
        $this->drupalGet('test/serialize/field', [], [
            'Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8',
        ]);
        $this->assertSession()
            ->responseHeaderEquals('content-type', 'text/html; charset=UTF-8');
        $this->assertSession()
            ->statusCodeEquals(406);
        // Ensure a request for HTML returns 406 Not Acceptable.
        $this->drupalGet('test/serialize/field', [
            'query' => [
                '_format' => 'html',
            ],
        ]);
        $this->assertSession()
            ->responseHeaderEquals('content-type', 'text/html; charset=UTF-8');
        $this->assertSession()
            ->statusCodeEquals(406);
        // Ensure a request for JSON returns 200 OK.
        $this->drupalGet('test/serialize/field', [
            'query' => [
                '_format' => 'json',
            ],
        ]);
        $this->assertSession()
            ->responseHeaderEquals('content-type', 'application/json');
        $this->assertSession()
            ->statusCodeEquals(200);
        // Ensure a request XML returns 200 OK.
        $this->drupalGet('test/serialize/field', [
            'query' => [
                '_format' => 'xml',
            ],
        ]);
        $this->assertSession()
            ->responseHeaderEquals('content-type', 'text/xml; charset=UTF-8');
        $this->assertSession()
            ->statusCodeEquals(200);
        // Now configure no format, so both serialization formats should be allowed.
        $this->drupalGet($style_options);
        $this->submitForm([
            'style_options[formats][json]' => '0',
            'style_options[formats][xml]' => '0',
        ], 'Apply');
        // Ensure a request for JSON returns 200 OK.
        $this->drupalGet('test/serialize/field', [
            'query' => [
                '_format' => 'json',
            ],
        ]);
        $this->assertSession()
            ->responseHeaderEquals('content-type', 'application/json');
        $this->assertSession()
            ->statusCodeEquals(200);
        // Ensure a request for XML returns 200 OK.
        $this->drupalGet('test/serialize/field', [
            'query' => [
                '_format' => 'xml',
            ],
        ]);
        $this->assertSession()
            ->responseHeaderEquals('content-type', 'text/xml; charset=UTF-8');
        $this->assertSession()
            ->statusCodeEquals(200);
        // Should return a 406 for HTML still.
        $this->drupalGet('test/serialize/field', [
            'query' => [
                '_format' => 'html',
            ],
        ]);
        $this->assertSession()
            ->responseHeaderEquals('content-type', 'text/html; charset=UTF-8');
        $this->assertSession()
            ->statusCodeEquals(406);
    }
    
    /**
     * Tests the field ID alias functionality of the DataFieldRow plugin.
     */
    public function testUIFieldAlias() {
        $this->drupalLogin($this->adminUser);
        // Test the UI settings for adding field ID aliases.
        $this->drupalGet('admin/structure/views/view/test_serializer_display_field/edit/rest_export_1');
        $row_options = 'admin/structure/views/nojs/display/test_serializer_display_field/rest_export_1/row_options';
        $this->assertSession()
            ->linkByHrefExists($row_options);
        // Test an empty string for an alias, this should not be used. This also
        // tests that the form can be submitted with no aliases.
        $this->drupalGet($row_options);
        $this->submitForm([
            'row_options[field_options][name][alias]' => '',
        ], 'Apply');
        $this->submitForm([], 'Save');
        $view = Views::getView('test_serializer_display_field');
        $view->setDisplay('rest_export_1');
        $this->executeView($view);
        $expected = [];
        foreach ($view->result as $row) {
            $expected_row = [];
            foreach ($view->field as $id => $field) {
                $expected_row[$id] = $field->render($row);
            }
            $expected[] = $expected_row;
        }
        $this->assertEquals($expected, Json::decode($this->drupalGet('test/serialize/field', [
            'query' => [
                '_format' => 'json',
            ],
        ])));
        // Test a random aliases for fields, they should be replaced.
        $alias_map = [
            'name' => $this->randomMachineName(),
            // Use # to produce an invalid character for the validation.
'nothing' => '#' . $this->randomMachineName(),
            'created' => 'created',
        ];
        $edit = [
            'row_options[field_options][name][alias]' => $alias_map['name'],
            'row_options[field_options][nothing][alias]' => $alias_map['nothing'],
        ];
        $this->drupalGet($row_options);
        $this->submitForm($edit, 'Apply');
        $this->assertSession()
            ->pageTextContains('The machine-readable name must contain only letters, numbers, dashes and underscores.');
        // Change the map alias value to a valid one.
        $alias_map['nothing'] = $this->randomMachineName();
        $edit = [
            'row_options[field_options][name][alias]' => $alias_map['name'],
            'row_options[field_options][nothing][alias]' => $alias_map['nothing'],
        ];
        $this->drupalGet($row_options);
        $this->submitForm($edit, 'Apply');
        $this->submitForm([], 'Save');
        $view = Views::getView('test_serializer_display_field');
        $view->setDisplay('rest_export_1');
        $this->executeView($view);
        $expected = [];
        foreach ($view->result as $row) {
            $expected_row = [];
            foreach ($view->field as $id => $field) {
                $expected_row[$alias_map[$id]] = $field->render($row);
            }
            $expected[] = $expected_row;
        }
        $this->assertEquals($expected, Json::decode($this->drupalGet('test/serialize/field', [
            'query' => [
                '_format' => 'json',
            ],
        ])));
    }
    
    /**
     * Tests the raw output options for row field rendering.
     */
    public function testFieldRawOutput() {
        $this->drupalLogin($this->adminUser);
        // Test the UI settings for adding field ID aliases.
        $this->drupalGet('admin/structure/views/view/test_serializer_display_field/edit/rest_export_1');
        $row_options = 'admin/structure/views/nojs/display/test_serializer_display_field/rest_export_1/row_options';
        $this->assertSession()
            ->linkByHrefExists($row_options);
        // Test an empty string for an alias, this should not be used. This also
        // tests that the form can be submitted with no aliases.
        $values = [
            'row_options[field_options][created][raw_output]' => '1',
            'row_options[field_options][name][raw_output]' => '1',
        ];
        $this->drupalGet($row_options);
        $this->submitForm($values, 'Apply');
        $this->submitForm([], 'Save');
        $view = Views::getView('test_serializer_display_field');
        $view->setDisplay('rest_export_1');
        $this->executeView($view);
        $storage = $this->container
            ->get('entity_type.manager')
            ->getStorage('entity_test');
        // Update the name for each to include a script tag.
        foreach ($storage->loadMultiple() as $entity_test) {
            $name = $entity_test->name->value;
            $entity_test->set('name', "<script>{$name}</script>");
            $entity_test->save();
        }
        // Just test the raw 'created' value against each row.
        foreach (Json::decode($this->drupalGet('test/serialize/field', [
            'query' => [
                '_format' => 'json',
            ],
        ])) as $index => $values) {
            $this->assertSame($view->result[$index]->views_test_data_created, $values['created'], 'Expected raw created value found.');
            $this->assertSame($view->result[$index]->views_test_data_name, $values['name'], 'Expected raw name value found.');
        }
        // Test result with an excluded field.
        $view->setDisplay('rest_export_1');
        $view->displayHandlers
            ->get('rest_export_1')
            ->overrideOption('fields', [
            'name' => [
                'id' => 'name',
                'table' => 'views_test_data',
                'field' => 'name',
                'relationship' => 'none',
            ],
            'created' => [
                'id' => 'created',
                'exclude' => TRUE,
                'table' => 'views_test_data',
                'field' => 'created',
                'relationship' => 'none',
            ],
        ]);
        $view->save();
        $this->executeView($view);
        foreach (Json::decode($this->drupalGet('test/serialize/field', [
            'query' => [
                '_format' => 'json',
            ],
        ])) as $index => $values) {
            $this->assertTrue(!isset($values['created']), 'Excluded value not found.');
        }
        // Test that the excluded field is not shown in the row options.
        $this->drupalGet('admin/structure/views/nojs/display/test_serializer_display_field/rest_export_1/row_options');
        $this->assertSession()
            ->pageTextNotContains('created');
    }
    
    /**
     * Tests the live preview output for json output.
     */
    public function testLivePreview() {
        // We set up a request so it looks like a request in the live preview.
        $request = new Request();
        $request->query
            ->add([
            MainContentViewSubscriber::WRAPPER_FORMAT => 'drupal_ajax',
        ]);
        
        /** @var \Symfony\Component\HttpFoundation\RequestStack $request_stack */
        $request_stack = \Drupal::service('request_stack');
        $request_stack->push($request);
        $view = Views::getView('test_serializer_display_entity');
        $view->setDisplay('rest_export_1');
        $this->executeView($view);
        // Get the serializer service.
        $serializer = $this->container
            ->get('serializer');
        $entities = [];
        foreach ($view->result as $row) {
            $entities[] = $row->_entity;
        }
        $expected = $serializer->serialize($entities, 'json');
        $view->live_preview = TRUE;
        $build = $view->preview();
        $rendered_json = $build['#plain_text'];
        $this->assertArrayNotHasKey('#markup', $build);
        $this->assertSame($expected, $rendered_json, 'Ensure the previewed json is escaped.');
        $view->destroy();
        $expected = $serializer->serialize($entities, 'xml');
        // Change the request format to xml.
        $view->setDisplay('rest_export_1');
        $view->getDisplay()
            ->setOption('style', [
            'type' => 'serializer',
            'options' => [
                'uses_fields' => FALSE,
                'formats' => [
                    'xml' => 'xml',
                ],
            ],
        ]);
        $this->executeView($view);
        $build = $view->preview();
        $rendered_xml = $build['#plain_text'];
        $this->assertEquals($expected, $rendered_xml, 'Ensure we preview xml when we change the request format.');
    }
    
    /**
     * Tests the views interface for REST export displays.
     */
    public function testSerializerViewsUI() {
        $this->drupalLogin($this->adminUser);
        // Click the "Update preview button".
        $this->drupalGet('admin/structure/views/view/test_serializer_display_field/edit/rest_export_1');
        $this->submitForm($edit = [], 'Update preview');
        $this->assertSession()
            ->statusCodeEquals(200);
        // Check if we receive the expected result.
        $result = $this->assertSession()
            ->elementExists('xpath', '//div[@id="views-live-preview"]/pre');
        $json_preview = $result->getText();
        $this->assertSame($json_preview, $this->drupalGet('test/serialize/field', [
            'query' => [
                '_format' => 'json',
            ],
        ]), 'The expected JSON preview output was found.');
    }
    
    /**
     * Tests the field row style using fieldapi fields.
     */
    public function testFieldapiField() {
        $this->drupalCreateContentType([
            'type' => 'page',
        ]);
        $node = $this->drupalCreateNode();
        $result = Json::decode($this->drupalGet('test/serialize/node-field', [
            'query' => [
                '_format' => 'json',
            ],
        ]));
        $this->assertEquals($node->id(), $result[0]['nid']);
        $this->assertEquals($node->body->processed, $result[0]['body']);
        // Make sure that serialized fields are not exposed to XSS.
        $node = $this->drupalCreateNode();
        $node->body = [
            'value' => '<script type="text/javascript">alert("node-body");</script>' . $this->randomMachineName(32),
            'format' => filter_default_format(),
        ];
        $node->save();
        $result = Json::decode($this->drupalGet('test/serialize/node-field', [
            'query' => [
                '_format' => 'json',
            ],
        ]));
        $this->assertEquals($node->id(), $result[1]['nid']);
        $this->assertStringNotContainsString("<script", $this->getSession()
            ->getPage()
            ->getContent(), "No script tag is present in the raw page contents.");
        $this->drupalLogin($this->adminUser);
        // Add an alias and make the output raw.
        $row_options = 'admin/structure/views/nojs/display/test_serializer_node_display_field/rest_export_1/row_options';
        // Test an empty string for an alias, this should not be used. This also
        // tests that the form can be submitted with no aliases.
        $this->drupalGet($row_options);
        $this->submitForm([
            'row_options[field_options][title][raw_output]' => '1',
        ], 'Apply');
        $this->submitForm([], 'Save');
        $view = Views::getView('test_serializer_node_display_field');
        $view->setDisplay('rest_export_1');
        $this->executeView($view);
        // Test the raw 'created' value against each row.
        foreach (Json::decode($this->drupalGet('test/serialize/node-field', [
            'query' => [
                '_format' => 'json',
            ],
        ])) as $index => $values) {
            $this->assertSame($view->result[$index]->_entity->title->value, $values['title'], 'Expected raw title value found.');
        }
        // Test that multiple raw body fields are shown.
        // Set the body field to unlimited cardinality.
        $storage_definition = $node->getFieldDefinition('body')
            ->getFieldStorageDefinition();
        $storage_definition->setCardinality(FieldStorageDefinitionInterface::CARDINALITY_UNLIMITED);
        $storage_definition->save();
        $this->drupalGet($row_options);
        $this->submitForm([
            'row_options[field_options][body][raw_output]' => '1',
        ], 'Apply');
        $this->submitForm([], 'Save');
        $node = $this->drupalCreateNode();
        $body = [
            'value' => '<script type="text/javascript">alert("node-body");</script>' . $this->randomMachineName(32),
            'format' => filter_default_format(),
        ];
        // Add two body items.
        $node->body = [
            $body,
            $body,
        ];
        $node->save();
        $view = Views::getView('test_serializer_node_display_field');
        $view->setDisplay('rest_export_1');
        $this->executeView($view);
        $result = Json::decode($this->drupalGet('test/serialize/node-field', [
            'query' => [
                '_format' => 'json',
            ],
        ]));
        $this->assertSame($node->body
            ->count(), count($result[2]['body']), 'Expected count of values');
        $this->assertEquals($result[2]['body'], array_map(function ($item) {
            return $item['value'];
        }, $node->body
            ->getValue()), 'Expected raw body values found.');
    }
    
    /**
     * Tests the "Grouped rows" functionality.
     */
    public function testGroupRows() {
        $this->drupalCreateContentType([
            'type' => 'page',
        ]);
        // Create a text field with cardinality set to unlimited.
        $field_name = 'field_group_rows';
        $field_storage = FieldStorageConfig::create([
            'field_name' => $field_name,
            'entity_type' => 'node',
            'type' => 'string',
            'cardinality' => FieldStorageDefinitionInterface::CARDINALITY_UNLIMITED,
        ]);
        $field_storage->save();
        // Create an instance of the text field on the content type.
        $field = FieldConfig::create([
            'field_storage' => $field_storage,
            'bundle' => 'page',
        ]);
        $field->save();
        $grouped_field_values = [
            'a',
            'b',
            'c',
        ];
        $edit = [
            'title' => $this->randomMachineName(),
            $field_name => $grouped_field_values,
        ];
        $this->drupalCreateNode($edit);
        $view = Views::getView('test_serializer_node_display_field');
        $view->setDisplay('rest_export_1');
        // Override the view's fields to include the field_group_rows field, set the
        // group_rows setting to true.
        $fields = [
            $field_name => [
                'id' => $field_name,
                'table' => 'node__' . $field_name,
                'field' => $field_name,
                'type' => 'string',
                'group_rows' => TRUE,
            ],
        ];
        $view->displayHandlers
            ->get('default')
            ->overrideOption('fields', $fields);
        $build = $view->preview();
        // Get the serializer service.
        $serializer = $this->container
            ->get('serializer');
        // Check if the field_group_rows field is grouped.
        $expected = [];
        $expected[] = [
            $field_name => implode(', ', $grouped_field_values),
        ];
        $this->assertEquals($serializer->serialize($expected, 'json'), (string) $this->renderer
            ->renderRoot($build));
        // Set the group rows setting to false.
        $view = Views::getView('test_serializer_node_display_field');
        $view->setDisplay('rest_export_1');
        $fields[$field_name]['group_rows'] = FALSE;
        $view->displayHandlers
            ->get('default')
            ->overrideOption('fields', $fields);
        $build = $view->preview();
        // Check if the field_group_rows field is ungrouped and displayed per row.
        $expected = [];
        foreach ($grouped_field_values as $grouped_field_value) {
            $expected[] = [
                $field_name => $grouped_field_value,
            ];
        }
        $this->assertEquals($serializer->serialize($expected, 'json'), (string) $this->renderer
            ->renderRoot($build));
    }
    
    /**
     * Tests the exposed filter works.
     *
     * There is an exposed filter on the title field which takes a title query
     * parameter. This is set to filter nodes by those whose title starts with
     * the value provided.
     */
    public function testRestViewExposedFilter() {
        $this->drupalCreateContentType([
            'type' => 'page',
        ]);
        $node0 = $this->drupalCreateNode([
            'title' => 'Node 1',
        ]);
        $node1 = $this->drupalCreateNode([
            'title' => 'Node 11',
        ]);
        $node2 = $this->drupalCreateNode([
            'title' => 'Node 111',
        ]);
        // Test that no filter brings back all three nodes.
        $result = Json::decode($this->drupalGet('test/serialize/node-exposed-filter', [
            'query' => [
                '_format' => 'json',
            ],
        ]));
        $expected = [
            0 => [
                'nid' => $node0->id(),
                'body' => $node0->body->processed,
            ],
            1 => [
                'nid' => $node1->id(),
                'body' => $node1->body->processed,
            ],
            2 => [
                'nid' => $node2->id(),
                'body' => $node2->body->processed,
            ],
        ];
        $this->assertEquals($expected, $result, 'Querying a view with no exposed filter returns all nodes.');
        // Test that title starts with 'Node 11' query finds 2 of the 3 nodes.
        $result = Json::decode($this->drupalGet('test/serialize/node-exposed-filter', [
            'query' => [
                '_format' => 'json',
                'title' => 'Node 11',
            ],
        ]));
        $expected = [
            0 => [
                'nid' => $node1->id(),
                'body' => $node1->body->processed,
            ],
            1 => [
                'nid' => $node2->id(),
                'body' => $node2->body->processed,
            ],
        ];
        $cache_contexts = [
            'languages:language_content',
            'languages:language_interface',
            'theme',
            'request_format',
            'user.node_grants:view',
            'url',
        ];
        $this->assertEquals($expected, $result, 'Querying a view with a starts with exposed filter on the title returns nodes whose title starts with value provided.');
        $this->assertCacheContexts($cache_contexts);
    }
    
    /**
     * Tests multilingual entity rows.
     */
    public function testMulEntityRows() {
        // Create some languages.
        ConfigurableLanguage::createFromLangcode('l1')->save();
        ConfigurableLanguage::createFromLangcode('l2')->save();
        // Create an entity with no translations.
        $storage = \Drupal::entityTypeManager()->getStorage('entity_test_mul');
        $storage->create([
            'langcode' => 'l1',
            'name' => 'mul-none',
        ])
            ->save();
        // Create some entities with translations.
        $entity = $storage->create([
            'langcode' => 'l1',
            'name' => 'mul-l1-orig',
        ]);
        $entity->save();
        $entity->addTranslation('l2', [
            'name' => 'mul-l1-l2',
        ])
            ->save();
        $entity = $storage->create([
            'langcode' => 'l2',
            'name' => 'mul-l2-orig',
        ]);
        $entity->save();
        $entity->addTranslation('l1', [
            'name' => 'mul-l2-l1',
        ])
            ->save();
        // Get the names of the output.
        $json = $this->drupalGet('test/serialize/translated_entity', [
            'query' => [
                '_format' => 'json',
            ],
        ]);
        $decoded = $this->container
            ->get('serializer')
            ->decode($json, 'json');
        $names = [];
        foreach ($decoded as $item) {
            $names[] = $item['name'][0]['value'];
        }
        sort($names);
        // Check that the names are correct.
        $expected = [
            'mul-l1-l2',
            'mul-l1-orig',
            'mul-l2-l1',
            'mul-l2-orig',
            'mul-none',
        ];
        $this->assertSame($expected, $names, 'The translated content was found in the JSON.');
    }

}