Merge "Improve docs for Title::getInternalURL/getCanonicalURL"

[lhc/web/wiklou.git] / includes / libs / objectcache / IExpiringStore.php

diff --git a/includes/libs/objectcache/IExpiringStore.php b/includes/libs/objectcache/IExpiringStore.php
index 0e09f16..61a4c61 100644 (file)
--- a/includes/libs/objectcache/IExpiringStore.php
+++ b/includes/libs/objectcache/IExpiringStore.php
@@ -21,7 +21,7 @@
  */
 
 /**
- * Generic base class for storage interfaces.
+ * Generic interface for lightweight expiring object stores.
  *
  * Provides convenient TTL constants.
  *
@@ -30,6 +30,7 @@
  */
 interface IExpiringStore {
        // Constants for TTL values, in seconds
+       const TTL_SECOND = 1;
        const TTL_MINUTE = 60;
        const TTL_HOUR = 3600;
        const TTL_DAY = 86400; // 24 * 3600
@@ -43,16 +44,24 @@ interface IExpiringStore {
 
        const TTL_INDEFINITE = 0;
 
-       // Attribute and QoS constants; higher QOS values with the same prefix rank higher...
-       // Medium attributes constants related to emulation or media type
+       // Emulation/fallback medium attribute (e.g. SQLBagOStuff)
        const ATTR_EMULATION = 1;
+       // Quality of service constants for ATTR_EMULATION (higher means faster)
        const QOS_EMULATION_SQL = 1;
-       // Medium attributes constants related to replica consistency
-       const ATTR_SYNCWRITES = 2; // SYNC_WRITES flag support
+
+       // Replica synchronization/consistency attribute of medium when SYNC_WRITES is used
+       const ATTR_SYNCWRITES = 2;
+       // Quality of service constants for ATTR_SYNCWRITES (higher means more consistent)
        const QOS_SYNCWRITES_NONE = 1; // replication only supports eventual consistency or less
        const QOS_SYNCWRITES_BE = 2; // best effort synchronous with limited retries
        const QOS_SYNCWRITES_QC = 3; // write quorum applied directly to state machines where R+W > N
        const QOS_SYNCWRITES_SS = 4; // strict-serializable, nodes refuse reads if possible stale
+
        // Generic "unknown" value that is useful for comparisons (e.g. always good enough)
        const QOS_UNKNOWN = INF;
+
+       const ERR_NONE = 0; // no error
+       const ERR_NO_RESPONSE = 1; // no response
+       const ERR_UNREACHABLE = 2; // can't connect
+       const ERR_UNEXPECTED = 3; // response gave some error
 }