[opw-web] Cache user info lookups

[Owen Taylor <otaylor src gnome org>]

commit da1d152857d8c8b0976d50437b1523cd716c3617
Author: Owen W. Taylor <otaylor fishsoup net>
Date:   Sun Mar 9 12:45:53 2014 -0400

    Cache user info lookups

 classes/class_user.php |   41 +++++++++++++++++++++++++----------------
 1 files changed, 25 insertions(+), 16 deletions(-)
---
diff --git a/classes/class_user.php b/classes/class_user.php
index 32cff00..108efd5 100644
--- a/classes/class_user.php
+++ b/classes/class_user.php
@@ -258,23 +258,30 @@ class user
 
     function lookup_user($username)
     {
-        global $db;
-
-        // Get current session data
-        $sql = "SELECT is_admin, fullname, email FROM {$db->prefix}profiles " .
-               "WHERE username = ?";
-        $row = $db->query($sql, $username, true);
-        if ($row === false) {
-            return null;
-        } else {
-            $values = array();
-
-            $values['is_admin'] = $row['is_admin'] != 0;
-            $values['fullname'] = $row['fullname'];
-            $values['email'] = $row['email'];
-
-            return $values;
+        global $db, $cache;
+
+        $key = 'user_' . $username;
+        $values = $cache->get($key, 'users');
+
+        if ($values == false) {
+            // Get current session data
+            $sql = "SELECT is_admin, fullname, email FROM {$db->prefix}profiles " .
+                   "WHERE username = ?";
+            $row = $db->query($sql, $username, true);
+            if ($row === false) {
+                return null;
+            } else {
+                $values = array();
+
+                $values['is_admin'] = $row['is_admin'] != 0;
+                $values['fullname'] = $row['fullname'];
+                $values['email'] = $row['email'];
+
+                $cache->put($key, $values, 'users');
+            }
         }
+
+        return $values;
     }
 
     function create_user($provider, $identifier, $profile)
@@ -342,6 +349,8 @@ class user
                    "(provider, identifier, username) " .
                    "VALUES (:provider, :identifier, :username)";
         $db->query($sql, $params);
+
+        $cache->purge('users');
     }
 
     function finish_login($provider)