Token.php 12.4 KB
Newer Older
1 2 3 4 5 6 7 8 9
<?php

/**
 * @file
 * Definition of Drupal\Core\Utility\Token.
 */

namespace Drupal\Core\Utility;

10
use Drupal\Core\Cache\CacheBackendInterface;
11
use Drupal\Core\Extension\ModuleHandlerInterface;
12
use Drupal\Core\Language\LanguageInterface;
13
use Drupal\Core\Language\LanguageManagerInterface;
14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39

/**
 * Drupal placeholder/token replacement system.
 *
 * API functions for replacing placeholders in text with meaningful values.
 *
 * For example: When configuring automated emails, an administrator enters
 * standard text for the email. Variables like the title of a node and the date
 * the email was sent can be entered as placeholders like [node:title] and
 * [date:short]. When a Drupal module prepares to send the email, it can call
 * the Token::replace() function, passing in the text. The token system will
 * scan the text for placeholder tokens, give other modules an opportunity to
 * replace them with meaningful text, then return the final product to the
 * original module.
 *
 * Tokens follow the form: [$type:$name], where $type is a general class of
 * tokens like 'node', 'user', or 'comment' and $name is the name of a given
 * placeholder. For example, [node:title] or [node:created:since].
 *
 * In addition to raw text containing placeholders, modules may pass in an array
 * of objects to be used when performing the replacement. The objects should be
 * keyed by the token type they correspond to. For example:
 *
 * @code
 * // Load a node and a user, then replace tokens in the text.
 * $text = 'On [date:short], [user:name] read [node:title].';
40
 * $node = Node::load(1);
41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59
 * $user = user_load(1);
 *
 * // [date:...] tokens use the current date automatically.
 * $data = array('node' => $node, 'user' => $user);
 * return Token::replace($text, $data);
 * @endcode
 *
 * Some tokens may be chained in the form of [$type:$pointer:$name], where $type
 * is a normal token type, $pointer is a reference to another token type, and
 * $name is the name of a given placeholder. For example, [node:author:mail]. In
 * that example, 'author' is a pointer to the 'user' account that created the
 * node, and 'mail' is a placeholder available for any 'user'.
 *
 * @see Token::replace()
 * @see hook_tokens()
 * @see hook_token_info()
 */
class Token {

60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78
  /**
   * The tag to cache token info with.
   */
  const TOKEN_INFO_CACHE_TAG = 'token_info';

  /**
   * The token cache.
   *
   * @var \Drupal\Core\Cache\CacheBackendInterface
   */
  protected $cache;

  /**
   * The language manager.
   *
   * @var \Drupal\Core\Language\LanguageManagerInterface
   */
  protected $languageManager;

79 80 81
  /**
   * Token definitions.
   *
82
   * @var array[]|null
83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98
   *   An array of token definitions, or NULL when the definitions are not set.
   *
   * @see self::setInfo()
   * @see self::getInfo()
   * @see self::resetInfo()
   */
  protected $tokenInfo;

  /**
   * The module handler service.
   *
   * @var \Drupal\Core\Extension\ModuleHandlerInterface
   */
  protected $moduleHandler;

  /**
99
   * Constructs a new class instance.
100 101
   *
   * @param \Drupal\Core\Extension\ModuleHandlerInterface $module_handler
102 103 104 105 106
   *   The module handler.
   * @param \Drupal\Core\Cache\CacheBackendInterface $cache
   *   The token cache.
   * @param \Drupal\Core\Language\LanguageManagerInterface $language_manager
   *   The language manager.
107
   */
108 109 110
  public function __construct(ModuleHandlerInterface $module_handler, CacheBackendInterface $cache, LanguageManagerInterface $language_manager) {
    $this->cache = $cache;
    $this->languageManager = $language_manager;
111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138
    $this->moduleHandler = $module_handler;
  }

  /**
   * Replaces all tokens in a given string with appropriate values.
   *
   * @param string $text
   *   A string potentially containing replaceable tokens.
   * @param array $data
   *   (optional) An array of keyed objects. For simple replacement scenarios
   *   'node', 'user', and others are common keys, with an accompanying node or
   *   user object being the value. Some token types, like 'site', do not require
   *   any explicit information from $data and can be replaced even if it is
   *   empty.
   * @param array $options
   *   (optional) A keyed array of settings and flags to control the token
   *   replacement process. Supported options are:
   *   - langcode: A language code to be used when generating locale-sensitive
   *     tokens.
   *   - callback: A callback function that will be used to post-process the
   *     array of token replacements after they are generated. For example, a
   *     module using tokens in a text-only email might provide a callback to
   *     strip HTML entities from token values before they are inserted into the
   *     final text.
   *   - clear: A boolean flag indicating that tokens should be removed from the
   *     final text if no replacement value can be generated.
   *   - sanitize: A boolean flag indicating that tokens should be sanitized for
   *     display to a web browser. Defaults to TRUE. Developers who set this
139 140 141 142
   *     option to FALSE assume responsibility for running
   *     \Drupal\Component\Utility\Xss::filter(),
   *     \Drupal\Component\Utility\String::checkPlain() or other appropriate
   *     scrubbing functions before displaying data to users.
143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232
   *
   * @return string
   *   Text with tokens replaced.
   */
  public function replace($text, array $data = array(), array $options = array()) {
    $text_tokens = $this->scan($text);
    if (empty($text_tokens)) {
      return $text;
    }

    $replacements = array();
    foreach ($text_tokens as $type => $tokens) {
      $replacements += $this->generate($type, $tokens, $data, $options);
      if (!empty($options['clear'])) {
        $replacements += array_fill_keys($tokens, '');
      }
    }

    // Optionally alter the list of replacement values.
    if (!empty($options['callback'])) {
      $function = $options['callback'];
      $function($replacements, $data, $options);
    }

    $tokens = array_keys($replacements);
    $values = array_values($replacements);

    return str_replace($tokens, $values, $text);
  }

  /**
   * Builds a list of all token-like patterns that appear in the text.
   *
   * @param string $text
   *   The text to be scanned for possible tokens.
   *
   * @return array
   *   An associative array of discovered tokens, grouped by type.
   */
  public function scan($text) {
    // Matches tokens with the following pattern: [$type:$name]
    // $type and $name may not contain [ ] characters.
    // $type may not contain : or whitespace characters, but $name may.
    preg_match_all('/
      \[             # [ - pattern start
      ([^\s\[\]:]*)  # match $type not containing whitespace : [ or ]
      :              # : - separator
      ([^\[\]]*)     # match $name not containing [ or ]
      \]             # ] - pattern end
      /x', $text, $matches);

    $types = $matches[1];
    $tokens = $matches[2];

    // Iterate through the matches, building an associative array containing
    // $tokens grouped by $types, pointing to the version of the token found in
    // the source text. For example, $results['node']['title'] = '[node:title]';
    $results = array();
    for ($i = 0; $i < count($tokens); $i++) {
      $results[$types[$i]][$tokens[$i]] = $matches[0][$i];
    }

    return $results;
  }

  /**
   * Generates replacement values for a list of tokens.
   *
   * @param string $type
   *   The type of token being replaced. 'node', 'user', and 'date' are common.
   * @param array $tokens
   *   An array of tokens to be replaced, keyed by the literal text of the token
   *   as it appeared in the source text.
   * @param array $data
   *   (optional) An array of keyed objects. For simple replacement scenarios
   *   'node', 'user', and others are common keys, with an accompanying node or
   *   user object being the value. Some token types, like 'site', do not require
   *   any explicit information from $data and can be replaced even if it is
   *   empty.
   * @param array $options
   *   (optional) A keyed array of settings and flags to control the token
   *   replacement process. Supported options are:
   *   - langcode: A language code to be used when generating locale-sensitive
   *     tokens.
   *   - callback: A callback function that will be used to post-process the
   *     array of token replacements after they are generated. Can be used when
   *     modules require special formatting of token text, for example URL
   *     encoding or truncation to a specific length.
   *   - sanitize: A boolean flag indicating that tokens should be sanitized for
   *     display to a web browser. Developers who set this option to FALSE assume
233 234 235
   *     responsibility for running \Drupal\Component\Utility\Xss::filter(),
   *     \Drupal\Component\Utility\String::checkPlain() or other appropriate
   *     scrubbing functions before displaying data to users.
236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313
   *
   * @return array
   *   An associative array of replacement values, keyed by the original 'raw'
   *   tokens that were found in the source text. For example:
   *   $results['[node:title]'] = 'My new node';
   *
   * @see hook_tokens()
   * @see hook_tokens_alter()
   */
  public function generate($type, array $tokens, array $data = array(), array $options = array()) {
    $options += array('sanitize' => TRUE);
    $replacements = $this->moduleHandler->invokeAll('tokens', array($type, $tokens, $data, $options));

    // Allow other modules to alter the replacements.
    $context = array(
      'type' => $type,
      'tokens' => $tokens,
      'data' => $data,
      'options' => $options,
    );
    $this->moduleHandler->alter('tokens', $replacements, $context);

    return $replacements;
  }

  /**
   * Returns a list of tokens that begin with a specific prefix.
   *
   * Used to extract a group of 'chained' tokens (such as [node:author:name])
   * from the full list of tokens found in text. For example:
   * @code
   *   $data = array(
   *     'author:name' => '[node:author:name]',
   *     'title'       => '[node:title]',
   *     'created'     => '[node:created]',
   *   );
   *   $results = Token::findWithPrefix($data, 'author');
   *   $results == array('name' => '[node:author:name]');
   * @endcode
   *
   * @param array $tokens
   *   A keyed array of tokens, and their original raw form in the source text.
   * @param string $prefix
   *   A textual string to be matched at the beginning of the token.
   * @param string $delimiter
   *   (optional) A string containing the character that separates the prefix from
   *   the rest of the token. Defaults to ':'.
   *
   * @return array
   *   An associative array of discovered tokens, with the prefix and delimiter
   *   stripped from the key.
   */
  public function findWithPrefix(array $tokens, $prefix, $delimiter = ':') {
    $results = array();
    foreach ($tokens as $token => $raw) {
      $parts = explode($delimiter, $token, 2);
      if (count($parts) == 2 && $parts[0] == $prefix) {
        $results[$parts[1]] = $raw;
      }
    }
    return $results;
  }

  /**
   * Returns metadata describing supported tokens.
   *
   * The metadata array contains token type, name, and description data as well
   * as an optional pointer indicating that the token chains to another set of
   * tokens.
   *
   * @return array
   *   An associative array of token information, grouped by token type. The
   *   array structure is identical to that of hook_token_info().
   *
   * @see hook_token_info()
   */
  public function getInfo() {
    if (is_null($this->tokenInfo)) {
314
      $cache_id = 'token_info:' . $this->languageManager->getCurrentLanguage(LanguageInterface::TYPE_CONTENT)->getId();
315 316 317 318 319 320 321 322
      $cache = $this->cache->get($cache_id);
      if ($cache) {
        $this->tokenInfo = $cache->data;
      }
      else {
        $this->tokenInfo = $this->moduleHandler->invokeAll('token_info');
        $this->moduleHandler->alter('token_info', $this->tokenInfo);
        $this->cache->set($cache_id, $this->tokenInfo, CacheBackendInterface::CACHE_PERMANENT, array(
323
          static::TOKEN_INFO_CACHE_TAG,
324 325
        ));
      }
326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348
    }

    return $this->tokenInfo;
  }

  /**
   * Sets metadata describing supported tokens.
   *
   * @param array $tokens
   *   Token metadata that has an identical structure to the return value of
   *   hook_token_info().
   *
   * @see hook_token_info()
   */
  public function setInfo(array $tokens) {
    $this->tokenInfo = $tokens;
  }

  /**
   * Resets metadata describing supported tokens.
   */
  public function resetInfo() {
    $this->tokenInfo = NULL;
349 350 351
    $this->cache->deleteTags(array(
      static::TOKEN_INFO_CACHE_TAG => TRUE,
    ));
352 353
  }
}