Merge pull request #6 from matthiasmullie/master

Update reflecting suggestions since opening final review

Author: Seldaek

src/CacheException.php

@@ -0,0 +1,10 @@
+<?php
+
+namespace Psr\SimpleCache;
+
+/**
+ * Interface used for all types of exceptions thrown by the implementing library.
+ */
+interface CacheException
+{
+}

src/CacheInterface.php

@@ -5,84 +5,110 @@
 interface CacheInterface
 {
     /**
-     * Fetch a value from the cache.
+     * Fetches a value from the cache.
      *
-     * @param string $key     The unique key of this item in the cache
-     * @param mixed  $default Default value to return if the key does not exist
+     * @param string $key     The unique key of this item in the cache.
+     * @param mixed  $default Default value to return if the key does not exist.
      *
-     * @return mixed The value of the item from the cache, or $default in case of cache miss
+     * @return mixed The value of the item from the cache, or $default in case of cache miss.
+     *
+     * @throws \Psr\SimpleCache\InvalidArgumentException
+     *   MUST be thrown if the $key string is not a legal value.
      */
     public function get($key, $default = null);
 
     /**
-     * Persist data in the cache, uniquely referenced by a key with an optional expiration TTL time.
+     * Persists data in the cache, uniquely referenced by a key with an optional expiration TTL time.
      *
-     * @param string                $key   The key of the item to store
-     * @param mixed                 $value The value of the item to store
+     * @param string                $key   The key of the item to store.
+     * @param mixed                 $value The value of the item to store, must be serializable.
      * @param null|int|DateInterval $ttl   Optional. The TTL value of this item. If no value is sent and
      *                                     the driver supports TTL then the library may set a default value
      *                                     for it or let the driver take care of that.
      *
-     * @return bool True on success and false on failure
+     * @return bool True on success and false on failure.
+     *
+     * @throws \Psr\SimpleCache\InvalidArgumentException
+     *   MUST be thrown if the $key string is not a legal value.
      */
     public function set($key, $value, $ttl = null);
 
     /**
-     * Delete an item from the cache by its unique key
+     * Delete an item from the cache by its unique key.
+     *
+     * @param string $key The unique cache key of the item to delete.
      *
-     * @param string $key The unique cache key of the item to delete
+     * @return bool True if the item was successfully removed. False if there was an error.
      *
-     * @return void
+     * @throws \Psr\SimpleCache\InvalidArgumentException
+     *   MUST be thrown if the $key string is not a legal value.
      */
     public function delete($key);
 
     /**
-     * Wipe clean the entire cache's keys
+     * Wipes clean the entire cache's keys.
      *
-     * @return void
+     * @return bool True on success and false on failure.
      */
     public function clear();
 
     /**
-     * Obtain multiple cache items by their unique keys
+     * Obtains multiple cache items by their unique keys.
      *
-     * @param array|Traversable $keys A list of keys that can obtained in a single operation.
+     * @param array|\Traversable $keys    A list of keys that can obtained in a single operation.
+     * @param mixed              $default Default value to return for keys that do not exist.
      *
-     * @return array An array of key => value pairs. Cache keys that do not exist or are stale will have a value of null.
+     * @return array|\Traversable A list of key => value pairs. Cache keys that do not exist or are stale will have $default as value.
+     *
+     * @throws \Psr\SimpleCache\InvalidArgumentException
+     *   MUST be thrown if $keys is neither an array nor a Traversable,
+     *   or if any of the $keys are not a legal value.
      */
-    public function getMultiple($keys);
+    public function getMultiple($keys, $default = null);
 
     /**
-     * Persisting a set of key => value pairs in the cache, with an optional TTL.
+     * Persists a set of key => value pairs in the cache, with an optional TTL.
      *
-     * @param array|Traversable     $items An array of key => value pairs for a multiple-set operation.
-     * @param null|int|DateInterval $ttl   Optional. The TTL value of this item. If no value is sent and
-     *                                     the driver supports TTL then the library may set a default value
-     *                                     for it or let the driver take care of that.
+     * @param array|\Traversable    $values A list of key => value pairs for a multiple-set operation.
+     * @param null|int|DateInterval $ttl    Optional. The TTL value of this item. If no value is sent and
+     *                                      the driver supports TTL then the library may set a default value
+     *                                      for it or let the driver take care of that.
+     *
+     * @return bool True on success and false on failure.
      *
-     * @return bool True on success and false on failure
+     * @throws \Psr\SimpleCache\InvalidArgumentException
+     *   MUST be thrown if $values is neither an array nor a Traversable,
+     *   or if any of the $values are not a legal value.
      */
-    public function setMultiple($items, $ttl = null);
+    public function setMultiple($values, $ttl = null);
 
     /**
-     * Delete multiple cache items in a single operation
+     * Deletes multiple cache items in a single operation.
+     *
+     * @param array|\Traversable $keys A list of string-based keys to be deleted.
      *
-     * @param array|Traversable $keys The array of string-based keys to be deleted
+     * @return bool True if the item was successfully removed. False if there was an error.
      *
-     * @return void
+     * @throws \Psr\SimpleCache\InvalidArgumentException
+     *   MUST be thrown if $keys is neither an array nor a Traversable,
+     *   or if any of the $keys are not a legal value.
      */
     public function deleteMultiple($keys);
 
     /**
-     * Identify if an item is in the cache.
+     * Determines whether an item is present in the cache.
+     *
      * NOTE: It is recommended that has() is only to be used for cache warming type purposes
      * and not to be used within your live applications operations for get/set, as this method
      * is subject to a race condition where your has() will return true and immediately after,
      * another script can remove it making the state of your app out of date.
      *
-     * @param string $key The cache item key
+     * @param string $key The cache item key.
      *
      * @return bool
+     *
+     * @throws \Psr\SimpleCache\InvalidArgumentException
+     *   MUST be thrown if the $key string is not a legal value.
      */
     public function has($key);
 }

src/CounterInterface.php

@@ -0,0 +1,13 @@
+<?php
+
+namespace Psr\SimpleCache;
+
+/**
+ * Exception interface for invalid cache arguments.
+ *
+ * When an invalid argument is passed it must throw an exception which implements
+ * this interface
+ */
+interface InvalidArgumentException extends CacheException
+{
+}