mwdocgen: support multiple --file values

[lhc/web/wiklou.git] / includes / PoolCounter.php

diff --git a/includes/PoolCounter.php b/includes/PoolCounter.php
index c6a3077..2dac938 100644 (file)
--- a/includes/PoolCounter.php
+++ b/includes/PoolCounter.php
@@ -135,7 +135,7 @@ class PoolCounter_Stub extends PoolCounter {
 }
 
 /**
- * Handy class for dealing with PoolCounters using class members instead of callbacks.
+ * Class for dealing with PoolCounters using class members
  */
 abstract class PoolCounterWork {
        protected $cacheable = false; //Does this override getCachedWork() ?
@@ -190,9 +190,19 @@ abstract class PoolCounterWork {
        }
 
        /**
-        * Get the result of the work (whatever it is), or false.
+        * Get the result of the work (whatever it is), or the result of the error() function.
+        * This returns the result of the first applicable method that returns a non-false value,
+        * where the methods are checked in the following order:
+        *   - a) doWork()       : Applies if the work is exclusive or no another process
+        *                         is doing it, and on the condition that either this process
+        *                         successfully entered the pool or the pool counter is down.
+        *   - b) doCachedWork() : Applies if the work is cacheable and this blocked on another
+        *                         process which finished the work.
+        *   - c) fallback()     : Applies for all remaining cases.
+        * If these all fall through (by returning false), then the result of error() is returned.
+        *
         * @param $skipcache bool
-        * @return bool|mixed
+        * @return mixed
         */
        public function execute( $skipcache = false ) {
                if ( $this->cacheable && !$skipcache ) {
@@ -247,3 +257,73 @@ abstract class PoolCounterWork {
                }
        }
 }
+
+/**
+ * Convenience class for dealing with PoolCounters using callbacks
+ * @since 1.22
+ */
+class PoolCounterWorkViaCallback extends PoolCounterWork {
+       /** @var callable */
+       protected $doWork;
+       /** @var callable|null */
+       protected $doCachedWork;
+       /** @var callable|null */
+       protected $fallback;
+       /** @var callable|null */
+       protected $error;
+
+       /**
+        * Build a PoolCounterWork class from a type, key, and callback map.
+        *
+        * The callback map must at least have a callback for the 'doWork' method.
+        * Additionally, callbacks can be provided for the 'doCachedWork', 'fallback',
+        * and 'error' methods. Methods without callbacks will be no-ops that return false.
+        * If a 'doCachedWork' callback is provided, then execute() may wait for any prior
+        * process in the pool to finish and reuse its cached result.
+        *
+        * @param string $type
+        * @param string $key
+        * @param array $callbacks Map of callbacks
+        * @throws MWException
+        */
+       public function __construct( $type, $key, array $callbacks ) {
+               parent::__construct( $type, $key );
+               foreach ( array( 'doWork', 'doCachedWork', 'fallback', 'error' ) as $name ) {
+                       if ( isset( $callbacks[$name] ) ) {
+                               if ( !is_callable( $callbacks[$name] ) ) {
+                                       throw new MWException( "Invalid callback provided for '$name' function." );
+                               }
+                               $this->$name = $callbacks[$name];
+                       }
+               }
+               if ( !isset( $this->doWork ) ) {
+                       throw new MWException( "No callback provided for 'doWork' function." );
+               }
+               $this->cacheable = isset( $this->doCachedWork );
+       }
+
+       public function doWork() {
+               return call_user_func_array( $this->doWork, array() );
+       }
+
+       public function getCachedWork() {
+               if ( $this->doCachedWork ) {
+                       return call_user_func_array( $this->doCachedWork, array() );
+               }
+               return false;
+       }
+
+       function fallback() {
+               if ( $this->fallback ) {
+                       return call_user_func_array( $this->fallback, array() );
+               }
+               return false;
+       }
+
+       function error( $status ) {
+               if ( $this->error ) {
+                       return call_user_func_array( $this->error, array( $status ) );
+               }
+               return false;
+       }
+}