Add wrapper to Views Rest JSON Output

Question

I am rebuilding an API in Drupal. The structure of the JSON must remain the same.

I am using Views and Draggable Views so the user can order items on an overview page. I Enabled the view for exporting REST JSON.

The response JSON must have a structure like this

{
  items: [{...},{...}]
}

But currently views output is like this

{[{...},{...}]}

I already managed to get my desired output without views and a special export controller but unfortunately, I need draggable views in additions to views. I also managed to create nested structures with Entity Normalizers inside an item but I want the whole output of the view is wrapped in "items". Any help would be appreciated.

Answer 1

You can write a views style plugin to get through this fast. Here is an example of that, which adds an outer wrapper of results plus a totalCount item:

<?php

namespace Drupal\mymodule\Plugin\views\style;

use Drupal\rest\Plugin\views\style\Serializer;

/**
 * The style plugin for serialized output formats.
 *
 * @ingroup views_style_plugins
 *
 * @ViewsStyle(
 *   id = "serializer_count",
 *   title = @Translation("Serializer with Count"),
 *   help = @Translation("Serializes views row data using the Serializer component and adds a count."),
 *   display_types = {"data"}
 * )
 */
class SerializerCount extends Serializer {

  /**
   * {@inheritdoc}
   */
  public function render() {
    $rows = [];

    if (isset($this->view->pager)) {
      $count = $this->view->pager->getTotalItems();
    }
    else {
      $count = 0;
    }

    // If the Data Entity row plugin is used, this will be an array of entities
    // which will pass through Serializer to one of the registered Normalizers,
    // which will transform it to arrays/scalars. If the Data field row plugin
    // is used, $rows will not contain objects and will pass directly to the
    // Encoder.
    foreach ($this->view->result as $row_index => $row) {
      $this->view->row_index = $row_index;
      $rows[$row_index] = $this->view->rowPlugin->render($row);
    }

    unset($this->view->row_index);

    // Get the content type configured in the display or fallback to the
    // default.
    if ((empty($this->view->live_preview))) {
      $content_type = $this->displayHandler->getContentType();
    }
    else {
      $content_type = !empty($this->options['formats']) ? reset($this->options['formats']) : 'json';
    }

    return $this->serializer->serialize(['results' => ['items' => $rows, 'totalCount' => (int) $count]], $content_type, ['views_style_plugin' => $this]);
  }

}

Then clear cache, and change the plugin for the View under "Style".

So in your case, the final line would look like:

return $this->serializer->serialize(['items' => $rows], $content_type, ['views_style_plugin' => $this]);

Answer 2

Drupal's Core Serializer does not provide options to customize the json, nor does it include the pagination data.

The Pager Serializer module does include the pagination information, and the property names are customizable, so your api can remain unchanged.

By default, it produces something like this.

{
  rows: [
    {...},
    {...}
  ],
  pager: {
    current_page: 0,
    total_items: 6,
    total_pages: 2,
    items_per_page: 5,
  }
}

Use the module's configuration form to customize the rows key, and disable the unneeded properties to meet your needs.

{
  items: [
    {...},
    {...}
  ]
}

or if you need the total count as provided in the answer by @kevin.

{
  items: [
    {...},
    {...}
  ],
  totalCount: 6
}

or

{
  items: [
    {...},
    {...}
  ],
  pager: {
    total_items: 6
  }
}