Add 0 hold-off TTL support to WANObjectCache::delete()

This removes the peculiar >= 1 restriction

Change-Id: I255dc6ef9750ad2ed6234e3fcfed9ae22a038748

diff --git a/includes/libs/objectcache/WANObjectCache.php b/includes/libs/objectcache/WANObjectCache.php
index 128999a..16e894e 100644 (file)
--- a/includes/libs/objectcache/WANObjectCache.php
+++ b/includes/libs/objectcache/WANObjectCache.php
@@ -101,6 +101,8 @@ class WANObjectCache implements IExpiringStore, LoggerAwareInterface {
        const TSE_NONE = -1;
        /** Max TTL to store keys when a data sourced is lagged */
        const TTL_LAGGED = 30;
+       /** Idiom for delete() for "no hold-off" */
+       const HOLDOFF_NONE = 0;
 
        /** Tiny negative float to use when CTL comes up >= 0 due to clock skew */
        const TINY_NEGATIVE = -0.000001;
@@ -254,7 +256,8 @@ class WANObjectCache implements IExpiringStore, LoggerAwareInterface {
                $checkKeyTimesForAll = $this->processCheckKeys( $checksForAll, $wrappedValues, $now );
                $checkKeyTimesByKey = array();
                foreach ( $checksByKey as $cacheKey => $checks ) {
-                       $checkKeyTimesByKey[$cacheKey] = $this->processCheckKeys( $checks, $wrappedValues, $now );
+                       $checkKeyTimesByKey[$cacheKey] =
+                               $this->processCheckKeys( $checks, $wrappedValues, $now );
                }
 
                // Get the main cache value for each key and validate them
@@ -456,7 +459,7 @@ class WANObjectCache implements IExpiringStore, LoggerAwareInterface {
         *
         * The $ttl parameter can be used when purging values that have not actually changed
         * recently. For example, a cleanup script to purge cache entries does not really need
-        * a hold-off period, so it can use the value 1. Likewise for user-requested purge.
+        * a hold-off period, so it can use HOLDOFF_NONE. Likewise for user-requested purge.
         * Note that $ttl limits the effective range of 'lockTSE' for getWithSetCallback().
         *
         * If called twice on the same key, then the last hold-off TTL takes precedence. For
@@ -468,12 +471,20 @@ class WANObjectCache implements IExpiringStore, LoggerAwareInterface {
         */
        final public function delete( $key, $ttl = self::HOLDOFF_TTL ) {
                $key = self::VALUE_KEY_PREFIX . $key;
-               // Avoid indefinite key salting for sanity
-               $ttl = max( $ttl, 1 );
-               // Update the local datacenter immediately
-               $ok = $this->cache->set( $key, self::PURGE_VAL_PREFIX . microtime( true ), $ttl );
-               // Publish the purge to all datacenters
-               return $this->relayPurge( $key, $ttl ) && $ok;
+
+               if ( $ttl <= 0 ) {
+                       // Update the local datacenter immediately
+                       $ok = $this->cache->delete( $key );
+                       // Publish the purge to all datacenters
+                       $ok = $this->relayDelete( $key ) && $ok;
+               } else {
+                       // Update the local datacenter immediately
+                       $ok = $this->cache->set( $key, self::PURGE_VAL_PREFIX . microtime( true ), $ttl );
+                       // Publish the purge to all datacenters
+                       $ok = $this->relayPurge( $key, $ttl ) && $ok;
+               }
+
+               return $ok;
        }
 
        /**

diff --git a/tests/phpunit/includes/libs/objectcache/WANObjectCacheTest.php b/tests/phpunit/includes/libs/objectcache/WANObjectCacheTest.php
index 90b4bd0..e2c6ac7 100644 (file)
--- a/tests/phpunit/includes/libs/objectcache/WANObjectCacheTest.php
+++ b/tests/phpunit/includes/libs/objectcache/WANObjectCacheTest.php
@@ -391,8 +391,22 @@ class WANObjectCacheTest extends MediaWikiTestCase {
                $this->assertLessThan( 0, $curTTL, "Deleted key has current TTL < 0" );
 
                $this->cache->set( $key, $value . 'more' );
+               $v = $this->cache->get( $key, $curTTL );
                $this->assertFalse( $v, "Deleted key is tombstoned and has false value" );
                $this->assertLessThan( 0, $curTTL, "Deleted key is tombstoned and has current TTL < 0" );
+
+               $this->cache->set( $key, $value );
+               $this->cache->delete( $key, WANObjectCache::HOLDOFF_NONE );
+
+               $curTTL = null;
+               $v = $this->cache->get( $key, $curTTL );
+               $this->assertFalse( $v, "Deleted key has false value" );
+               $this->assertNull( $curTTL, "Deleted key has null current TTL" );
+
+               $this->cache->set( $key, $value );
+               $v = $this->cache->get( $key, $curTTL );
+               $this->assertEquals( $value, $v, "Key was created with value" );
+               $this->assertGreaterThan( 0, $curTTL, "Existing key has current TTL > 0" );
        }
 
        /**