1<?php
2
3namespace Drupal\Core\Asset;
4
5use Drupal\Component\Utility\NestedArray;
6use Drupal\Core\Asset\Exception\InvalidLibrariesExtendSpecificationException;
7use Drupal\Core\Asset\Exception\InvalidLibrariesOverrideSpecificationException;
8use Drupal\Core\Cache\CacheCollector;
9use Drupal\Core\Cache\CacheBackendInterface;
10use Drupal\Core\Lock\LockBackendInterface;
11use Drupal\Core\Theme\ThemeManagerInterface;
12
13/**
14 * A CacheCollector implementation for building library extension info.
15 */
16class LibraryDiscoveryCollector extends CacheCollector {
17
18  /**
19   * The library discovery parser.
20   *
21   * @var \Drupal\Core\Asset\LibraryDiscoveryParser
22   */
23  protected $discoveryParser;
24
25  /**
26   * The theme manager.
27   *
28   * @var \Drupal\Core\Theme\ThemeManagerInterface
29   */
30  protected $themeManager;
31
32  /**
33   * Constructs a CacheCollector object.
34   *
35   * @param \Drupal\Core\Cache\CacheBackendInterface $cache
36   *   The cache backend.
37   * @param \Drupal\Core\Lock\LockBackendInterface $lock
38   *   The lock backend.
39   * @param \Drupal\Core\Asset\LibraryDiscoveryParser $discovery_parser
40   *   The library discovery parser.
41   * @param \Drupal\Core\Theme\ThemeManagerInterface $theme_manager
42   *   The theme manager.
43   */
44  public function __construct(CacheBackendInterface $cache, LockBackendInterface $lock, LibraryDiscoveryParser $discovery_parser, ThemeManagerInterface $theme_manager) {
45    $this->themeManager = $theme_manager;
46    parent::__construct(NULL, $cache, $lock, ['library_info']);
47
48    $this->discoveryParser = $discovery_parser;
49  }
50
51  /**
52   * {@inheritdoc}
53   */
54  protected function getCid() {
55    if (!isset($this->cid)) {
56      $this->cid = 'library_info:' . $this->themeManager->getActiveTheme()->getName();
57    }
58
59    return $this->cid;
60  }
61
62  /**
63   * {@inheritdoc}
64   */
65  protected function resolveCacheMiss($key) {
66    $this->storage[$key] = $this->getLibraryDefinitions($key);
67    $this->persist($key);
68
69    return $this->storage[$key];
70  }
71
72  /**
73   * Returns the library definitions for a given extension.
74   *
75   * This also implements libraries-overrides for entire libraries that have
76   * been specified by the LibraryDiscoveryParser.
77   *
78   * @param string $extension
79   *   The name of the extension for which library definitions will be returned.
80   *
81   * @return array
82   *   The library definitions for $extension with overrides applied.
83   *
84   * @throws \Drupal\Core\Asset\Exception\InvalidLibrariesOverrideSpecificationException
85   */
86  protected function getLibraryDefinitions($extension) {
87    $libraries = $this->discoveryParser->buildByExtension($extension);
88    foreach ($libraries as $name => $definition) {
89      // Handle libraries that are marked for override or removal.
90      // @see \Drupal\Core\Asset\LibraryDiscoveryParser::applyLibrariesOverride()
91      if (isset($definition['override'])) {
92        if ($definition['override'] === FALSE) {
93          // Remove the library definition if FALSE is given.
94          unset($libraries[$name]);
95        }
96        else {
97          // Otherwise replace with existing library definition if it exists.
98          // Throw an exception if it doesn't.
99          list($replacement_extension, $replacement_name) = explode('/', $definition['override']);
100          $replacement_definition = $this->get($replacement_extension);
101          if (isset($replacement_definition[$replacement_name])) {
102            $libraries[$name] = $replacement_definition[$replacement_name];
103          }
104          else {
105            throw new InvalidLibrariesOverrideSpecificationException(sprintf('The specified library %s does not exist.', $definition['override']));
106          }
107        }
108      }
109      else {
110        // If libraries are not overridden, then apply libraries-extend.
111        $libraries[$name] = $this->applyLibrariesExtend($extension, $name, $definition);
112      }
113    }
114    return $libraries;
115  }
116
117  /**
118   * Applies the libraries-extend specified by the active theme.
119   *
120   * This extends the library definitions with the those specified by the
121   * libraries-extend specifications for the active theme.
122   *
123   * @param string $extension
124   *   The name of the extension for which library definitions will be extended.
125   * @param string $library_name
126   *   The name of the library whose definitions is to be extended.
127   * @param $library_definition
128   *   The library definition to be extended.
129   *
130   * @return array
131   *   The library definition extended as specified by libraries-extend.
132   *
133   * @throws \Drupal\Core\Asset\Exception\InvalidLibrariesExtendSpecificationException
134   */
135  protected function applyLibrariesExtend($extension, $library_name, $library_definition) {
136    $libraries_extend = $this->themeManager->getActiveTheme()->getLibrariesExtend();
137    if (!empty($libraries_extend["$extension/$library_name"])) {
138      foreach ($libraries_extend["$extension/$library_name"] as $library_extend_name) {
139        if (isset($library_definition['deprecated'])) {
140          $extend_message = sprintf('Theme "%s" is extending a deprecated library.', $extension);
141          $library_deprecation = str_replace('%library_id%', "$extension/$library_name", $library_definition['deprecated']);
142          @trigger_error("$extend_message $library_deprecation", E_USER_DEPRECATED);
143        }
144        if (!is_string($library_extend_name)) {
145          // Only string library names are allowed.
146          throw new InvalidLibrariesExtendSpecificationException('The libraries-extend specification for each library must be a list of strings.');
147        }
148        list($new_extension, $new_library_name) = explode('/', $library_extend_name, 2);
149        $new_libraries = $this->get($new_extension);
150        if (isset($new_libraries[$new_library_name])) {
151          $library_definition = NestedArray::mergeDeep($library_definition, $new_libraries[$new_library_name]);
152        }
153        else {
154          throw new InvalidLibrariesExtendSpecificationException(sprintf('The specified library "%s" does not exist.', $library_extend_name));
155        }
156      }
157    }
158    return $library_definition;
159  }
160
161  /**
162   * {@inheritdoc}
163   */
164  public function reset() {
165    parent::reset();
166    $this->cid = NULL;
167  }
168
169}
170