New method Memcached_DataObject::pivotGet()

This method lets you get all the objects with a given variable key and
another set of "fixed" keys. A good example is getting all the avatars
for a notice list; the avatar size stays the same, but the IDs change.

Since it's very similar to multiGet(), I refactored that function to
use pivotGet().

And, yes, I realize these are kind of hard to follow.

diff --git a/classes/Memcached_DataObject.php b/classes/Memcached_DataObject.php
index 0eae9fb42a835e79087a0845f2449f85afd52e28..d964012a14c932c7fc7493be1848f4a3b474165c 100644 (file)
--- a/classes/Memcached_DataObject.php
+++ b/classes/Memcached_DataObject.php
@@ -75,13 +75,52 @@ class Memcached_DataObject extends Safe_DataObject
      * @return array Array of objects, in order
      */
     function multiGet($cls, $keyCol, $keyVals, $skipNulls=true)
+    {
+       $result = self::pivotGet($cls, $keyCol, $keyVals);
+       
+       common_log(LOG_INFO, sprintf("Got %d results for class %s with %d keys on column %s",
+                                count($result),
+                                $cls,
+                                count($keyVals),
+                                $keyCol));
+                                
+       $values = array_values($result);
+       
+       if ($skipNulls) {
+               $tmp = array();
+               foreach ($values as $value) {
+                       if (!empty($value)) {
+                               $tmp[] = $value;
+                       }
+               }
+               $values = $tmp;
+       }
+       
+       return new ArrayWrapper($values);
+    }
+    
+    /**
+     * Get multiple items from the database by key
+     * 
+     * @param string  $cls       Class to fetch
+     * @param string  $keyCol    name of column for key
+     * @param array   $keyVals   key values to fetch
+     * @param boolean $otherCols Other columns to hold fixed
+     * 
+     * @return array Array mapping $keyVals to objects, or null if not found
+     */
+    static function pivotGet($cls, $keyCol, $keyVals, $otherCols = array())
     {
        $result = array_fill_keys($keyVals, null);
        
        $toFetch = array();
        
        foreach ($keyVals as $keyVal) {
-               $i = self::getcached($cls, $keyCol, $keyVal);
+               
+               $kv = array_merge($otherCols, array($keyCol => $keyVal));
+               
+               $i = self::multicache($cls, $kv);
+               
                if ($i !== false) {
                        $result[$keyVal] = $i;
                } else if (!empty($keyVal)) {
@@ -93,6 +132,9 @@ class Memcached_DataObject extends Safe_DataObject
             $i = DB_DataObject::factory($cls);
             if (empty($i)) {
                throw new Exception(_('Cannot instantiate class ' . $cls));
+            }
+            foreach ($otherCols as $otherKeyCol => $otherKeyVal) {
+                $i->$otherKeyCol = $otherKeyVal;
             }
                $i->whereAddIn($keyCol, $toFetch, $i->columnType($keyCol));
                if ($i->find()) {
@@ -107,29 +149,18 @@ class Memcached_DataObject extends Safe_DataObject
                
                foreach ($toFetch as $keyVal) {
                        if (empty($result[$keyVal])) {
+                               $kv = array_merge($otherCols, array($keyCol => $keyVal));
                        // save the fact that no such row exists
                        $c = self::memcache();
                        if (!empty($c)) {
-                       $ck = self::cachekey($cls, $keyCol, $keyVal);
+                       $ck = self::multicacheKey($cls, $keyCol, $keyVal);
                        $c->set($ck, null);
                        }       
                        }
                }
        }
        
-       $values = array_values($result);
-       
-       if ($skipNulls) {
-               $tmp = array();
-               foreach ($values as $value) {
-                       if (!empty($value)) {
-                               $tmp[] = $value;
-                       }
-               }
-               $values = $tmp;
-       }
-       
-       return new ArrayWrapper($values);
+       return $result;
     }
 
        function columnType($columnName)