- Patch #113614 by eaton, fago, et al: add centralized token/placeholder subsituation to core.

2 files changed, 239 insertions, 0 deletions

diff --git a/includes/common.inc b/includes/common.inc
index f6e64cf47..4e701de9e 100644
--- a/includes/common.inc
+++ b/includes/common.inc
@@ -3549,6 +3549,7 @@ function _drupal_bootstrap_full() {
   require_once DRUPAL_ROOT . '/includes/mail.inc';
   require_once DRUPAL_ROOT . '/includes/actions.inc';
   require_once DRUPAL_ROOT . '/includes/ajax.inc';
+  require_once DRUPAL_ROOT . '/includes/token.inc';
   // Set the Drupal custom error handler.
   set_error_handler('_drupal_error_handler');
   set_exception_handler('_drupal_exception_handler');
diff --git a/includes/token.inc b/includes/token.inc
new file mode 100644
index 000000000..7f786121d
--- /dev/null
+++ b/includes/token.inc
@@ -0,0 +1,238 @@
+<?php
+// $Id$
+
+/**
+ * @file
+ * Drupal placeholder/token replacement system.
+ *
+ * Provides a set of extensible 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].
+ *
+ * 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].';
+ * $node = node_load(1);
+ * $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()
+ */
+
+/**
+ * Replace all tokens in a given string with appropriate values.
+ *
+ * @param $text
+ *   A string potentially containing replacable tokens.
+ * @param $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 $options
+ *   (optional) A keyed array of settings and flags to control the token
+ *   replacement process. Supported options are:
+ *   - language: A language object to be used when generating locale-sensitive
+ *     tokens.
+ *   - callback: A callback function that will be used to post-process the array
+ *     of token replacements after they are generated. For example, a module using
+ *     tokens in a text-only email might provide a callback to strip HTML
+ *     entities from token values before they are inserted into the final text.
+ *   - clear: A boolean flag indicating that tokens should be removed from the
+ *     final text if no replacement value can be generated.
+ *   - sanitize: A boolean flag indicating that tokens should be sanitized for
+ *     display to a web browser. Defaults to TRUE. Developers who set this option
+ *     to FALSE assume responsibility for running filter_xss(), check_plain() or
+ *     other appropriate scrubbing functions before displaying data to users.
+ * @return
+ *   Text with tokens replaced.
+ */
+function token_replace($text, array $data = array(), array $options = array()) {
+  $replacements = array();
+  foreach (token_scan($text) as $type => $tokens) {
+    $replacements += token_generate($type, $tokens, $data, $options);
+  }
+
+  // Optionally alter the list of replacement values.
+  if (!empty($options['callback']) && drupal_function_exists($options['callback'])) {
+    $function = $options['callback'];
+    $function($replacements, $data, $options);
+  }
+
+  $tokens = array_keys($replacements);
+  $values = array_values($replacements);
+  
+  return str_replace($tokens, $values, $text);
+}
+
+/**
+ * Build a list of all token-like patterns that appear in the text.
+ *
+ * @param $text
+ *   The text to be scanned for possible tokens.
+ * @return
+ *   An associative array of discovered tokens, grouped by type.
+ */
+function token_scan($text) {
+  // Matches tokens with the following pattern: [$type:$token]
+  // $type and $token may not contain white spaces.
+  preg_match_all('/\[([^\s\]:]*):([^\s\]]*)\]/', $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;
+}
+
+/**
+ * Generate replacement values for a list of tokens.
+ *
+ * @param $type
+ *   The type of token being replaced. 'node', 'user', and 'date' are common.
+ * @param $tokens
+ *   An array of tokens to be replaced, keyed by the literal text of the token
+ *   as it appeared in the source text.
+ * @param $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 $options
+ *   (optional) A keyed array of settings and flags to control the token
+ *   replacement process. Supported options are:
+ *   - 'language' A language object 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
+ *     responsibility for running filter_xss(), check_plain() or other
+ *     appropriate scrubbing functions before displaying data to users.
+ * @return
+ *   An associative array of replacement values, keyed by the original 'raw'
+ *   tokens that were found in the source text. For example:
+ *   $results['[node:title]'] = 'My new node';
+ */
+function token_generate($type, array $tokens, array $data = array(), array $options = array()) {
+  $results = array();
+  $options += array('sanitize' => TRUE);
+
+  foreach (module_implements('tokens') as $module) {
+    $function = $module . '_tokens';
+    if (drupal_function_exists($function)) {
+      $result = $function($type, $tokens, $data, $options);
+      foreach ($result as $original => $replacement) {
+        $results[$original] = $replacement;
+      }
+    }
+  }
+
+  return $results;
+}
+
+/**
+ * Given a list of tokens, return those 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:author:name]',
+ *   );
+ *   $results = token_find_with_prefix($data, 'author');
+ *   $results == array('name' => '[node:author:name]');
+ * @endcode
+ *
+ * @param $tokens
+ *   A keyed array of tokens, and their original raw form in the source text.
+ * @param $prefix
+ *   A textual string to be matched at the beginning of the token.
+ * @param $delimiter
+ *   An optional string containing the character that separates the prefix from
+ *   the rest of the token. Defaults to ':'.
+ * @return
+ *   An associative array of discovered tokens, with the prefix and delimiter
+ *   stripped from the key.
+ */
+function token_find_with_prefix(array $tokens, $prefix, $delimiter = ':') {
+  $results = array();
+  foreach ($tokens as $token => $raw) {
+    $parts = split($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.
+ * For example:
+ * @code
+ *   $data['types']['node'] = array(
+ *     'name' => t('Nodes'),
+ *     'description' => t('Tokens related to node objects.'),
+ *   );
+ *   $data['tokens']['node']['title'] = array(
+ *     'name' => t('Title'),
+ *     'description' => t('The title of the current node.'),
+ *   );
+ *   $data['tokens']['node']['author'] = array(
+ *     'name' => t('Author'),
+ *     'description' => t('The author of the current node.'),
+ *     'type' => 'user',
+ *   );
+ * @endcode
+ * @return
+ *   An associative array of token information, grouped by token type.
+ */
+function token_info() {
+  $data = &drupal_static(__FUNCTION__);
+  if (!isset($data)) {
+    $data = module_invoke_all('token_info');
+    drupal_alter('token_info', $data);
+  }
+  return $data;
+}