Allow user info to be retrieved without groups

Some parts of dokuwiki (e.g. recent changes, old revisions) can
requests lots of user info (to provide editor names) without
requiring any group information.

This change also implements caching of user info by authmysql &
authpgsql plugins to avoid repeated querying of the DB to retrieve
the same user information.

1 files changed, 126 insertions, 21 deletions

diff --git a/lib/plugins/authmysql/auth.php b/lib/plugins/authmysql/auth.php
index 1e6e6a4a9..774fce01f 100644
--- a/lib/plugins/authmysql/auth.php
+++ b/lib/plugins/authmysql/auth.php
@@ -21,6 +21,9 @@ class auth_plugin_authmysql extends DokuWiki_Auth_Plugin {
     /** @var int database subrevision */
     protected $dbsub = 0;
 
+    /** @var array cache to avoid re-reading user info data */
+    protected $cacheUserInfo = array();
+
     /**
      * Constructor
      *
@@ -174,12 +177,18 @@ class auth_plugin_authmysql extends DokuWiki_Auth_Plugin {
      * @author  Matthias Grimm <matthiasgrimm@users.sourceforge.net>
      *
      * @param string $user user login to get data for
+     * @param bool $requireGroups  when true, group membership information should be included in the returned array;
+     *                             when false, it maybe included, but is not required by the caller
      * @return array|bool
      */
-    public function getUserData($user) {
+    public function getUserData($user, $requireGroups=true) {
+        if($this->_cacheExists($user, $requireGroups)) {
+            return $this->cacheUserInfo[$user];
+        }
+
         if($this->_openDB()) {
             $this->_lockTables("READ");
-            $info = $this->_getUserInfo($user);
+            $info = $this->_getUserInfo($user, $requireGroups);
             $this->_unlockTables();
             $this->_closeDB();
         } else
@@ -262,21 +271,23 @@ class auth_plugin_authmysql extends DokuWiki_Auth_Plugin {
         if($this->_openDB()) {
             $this->_lockTables("WRITE");
 
-            if(($uid = $this->_getUserID($user))) {
-                $rc = $this->_updateUserInfo($changes, $uid);
+            $rc = $this->_updateUserInfo($user, $changes);
 
-                if($rc && isset($changes['grps']) && $this->cando['modGroups']) {
-                    $groups = $this->_getGroups($user);
-                    $grpadd = array_diff($changes['grps'], $groups);
-                    $grpdel = array_diff($groups, $changes['grps']);
+            if($rc && isset($changes['grps']) && $this->cando['modGroups']) {
+                $groups = $this->_getGroups($user);
+                $grpadd = array_diff($changes['grps'], $groups);
+                $grpdel = array_diff($groups, $changes['grps']);
 
-                    foreach($grpadd as $group)
-                        if(($this->_addUserToGroup($user, $group, 1)) == false)
-                            $rc = false;
+                foreach($grpadd as $group) {
+                    if(($this->_addUserToGroup($user, $group, 1)) == false) {
+                        $rc = false;
+                    }
+                }
 
-                    foreach($grpdel as $group)
-                        if(($this->_delUserFromGroup($user, $group)) == false)
-                            $rc = false;
+                foreach($grpdel as $group) {
+                    if(($this->_delUserFromGroup($user, $group)) == false) {
+                        $rc = false;
+                    }
                 }
             }
 
@@ -466,7 +477,10 @@ class auth_plugin_authmysql extends DokuWiki_Auth_Plugin {
             $sql = str_replace('%{user}', $this->_escape($user), $sql);
             $sql = str_replace('%{gid}', $this->_escape($gid), $sql);
             $sql = str_replace('%{group}', $this->_escape($group), $sql);
-            if($this->_modifyDB($sql) !== false) return true;
+            if($this->_modifyDB($sql) !== false) {
+                $this->_flushUserInfoCache($user);
+                return true;
+            }
 
             if($newgroup) { // remove previously created group on error
                 $sql = str_replace('%{gid}', $this->_escape($gid), $this->getConf('delGroup'));
@@ -501,6 +515,10 @@ class auth_plugin_authmysql extends DokuWiki_Auth_Plugin {
                 $sql = str_replace('%{gid}', $this->_escape($gid), $sql);
                 $sql = str_replace('%{group}', $this->_escape($group), $sql);
                 $rc  = $this->_modifyDB($sql) == 0 ? true : false;
+
+                if ($rc) {
+                    $this->_flushUserInfoCache($user);
+                }
             }
         }
         return $rc;
@@ -590,6 +608,7 @@ class auth_plugin_authmysql extends DokuWiki_Auth_Plugin {
                 }
 
                 if($gid !== false){
+                    $this->_flushUserInfoCache($user);
                     return true;
                 } else {
                     /* remove the new user and all group relations if a group can't
@@ -626,16 +645,96 @@ class auth_plugin_authmysql extends DokuWiki_Auth_Plugin {
                 $sql = str_replace('%{uid}', $this->_escape($uid), $this->getConf('delUser'));
                 $sql = str_replace('%{user}', $this->_escape($user), $sql);
                 $this->_modifyDB($sql);
+                $this->_flushUserInfoCache($user);
+                return true;
+            }
+        }
+        return false;
+    }
+
+    /**
+     * Flush cached user information
+     *
+     * @author Christopher Smith <chris@jalakai.co.uk>
+     *
+     * @param  string  $user username of the user whose data is to be removed from the cache
+     *                       if null, empty the whole cache
+     * @return none
+     */
+    protected function _flushUserInfoCache($user=null) {
+        if (is_null($user)) {
+            $this->cacheUserInfo = array();
+        } else {
+            unset($this->cacheUserInfo[$user]);
+        }
+    }
+
+    /**
+     * Quick lookup to see if a user's information has been cached
+     *
+     * This test does not need a database connection or read lock
+     *
+     * @author Christopher Smith <chris@jalakai.co.uk>
+     *
+     * @param  string  $user  username to be looked up in the cache
+     * @param  bool    $requireGroups  true, if cached info should include group memberships
+     *
+     * @return bool    existence of required user information in the cache
+     */
+    protected function _cacheExists($user, $requireGroups=true) {
+        if (isset($this->cacheUserInfo[$user])) {
+            if (!is_array($this->cacheUserInfo[$user])) {
+                return true;          // user doesn't exist
+            }
+
+            if (!$requireGroups || isset($this->cacheUserInfo[$user]['grps'])) {
                 return true;
             }
         }
+
         return false;
     }
 
     /**
-     * getUserInfo
+     * Get a user's information
+     *
+     * The database connection must already be established for this function to work.
+     *
+     * @author Christopher Smith <chris@jalakai.co.uk>
+     *
+     * @param  string  $user  username of the user whose information is being reterieved
+     * @param  bool    $requireGroups  true if group memberships should be included
+     * @param  bool    $useCache       true if ok to return cached data & to cache returned data
+     *
+     * @return mixed   false|array     false if the user doesn't exist
+     *                                 array containing user information if user does exist
+     */
+    protected function _getUserInfo($user, $requireGroups=true, $useCache=true) {
+        $info = null;
+
+        if ($useCache && isset($this->cacheUserInfo[$user])) {
+            $info = $this->cacheUserInfo[$user];
+        }
+
+        if (is_null($info)) {
+            $info = $this->_retrieveUserInfo($user);
+        }
+
+        if ($requireGroups && $info && !isset($info['grps'])) {
+            $info['grps'] = $this->_getGroups($user);
+        }
+
+        if ($useCache) {
+            $this->cacheUserInfo[$user] = $info;
+        }
+
+        return $info;
+    }
+
+    /**
+     * retrieveUserInfo
      *
-     * Gets the data for a specific user The database connection
+     * Gets the data for a specific user. The database connection
      * must already be established for this function to work.
      * Otherwise it will return 'false'.
      *
@@ -644,12 +743,11 @@ class auth_plugin_authmysql extends DokuWiki_Auth_Plugin {
      * @param  string $user  user's nick to get data for
      * @return bool|array false on error, user info on success
      */
-    protected function _getUserInfo($user) {
+    protected function _retrieveUserInfo($user) {
         $sql    = str_replace('%{user}', $this->_escape($user), $this->getConf('getUserInfo'));
         $result = $this->_queryDB($sql);
         if($result !== false && count($result)) {
             $info         = $result[0];
-            $info['grps'] = $this->_getGroups($user);
             return $info;
         }
         return false;
@@ -666,20 +764,26 @@ class auth_plugin_authmysql extends DokuWiki_Auth_Plugin {
      * The database connection has already to be established for this
      * function to work. Otherwise it will return 'false'.
      *
-     * The password will be crypted if necessary.
+     * The password will be encrypted if necessary.
      *
+     * @param  string $user    user's nick being updated
      * @param  array $changes  array of items to change as pairs of item and value
      * @param  mixed $uid      user id of dataset to change, must be unique in DB
      * @return bool true on success or false on error
      *
      * @author Matthias Grimm <matthiasgrimm@users.sourceforge.net>
      */
-    protected function _updateUserInfo($changes, $uid) {
+    protected function _updateUserInfo($user, $changes) {
         $sql = $this->getConf('updateUser')." ";
         $cnt = 0;
         $err = 0;
 
         if($this->dbcon) {
+            $uid = $this->_getUserID($user);
+            if ($uid === false) {
+                return false;
+            }
+
             foreach($changes as $item => $value) {
                 if($item == 'user') {
                     if(($this->_getUserID($changes['user']))) {
@@ -707,6 +811,7 @@ class auth_plugin_authmysql extends DokuWiki_Auth_Plugin {
                     $sql .= " ".str_replace('%{uid}', $uid, $this->getConf('UpdateTarget'));
                     if(get_class($this) == 'auth_mysql') $sql .= " LIMIT 1"; //some PgSQL inheritance comp.
                     $this->_modifyDB($sql);
+                    $this->_flushUserInfoCache($user);
                 }
                 return true;
             }