Add peek support for memcache::get (#108)

* Add peek support for memcache::get * Add peek support for memcached::get

Author: MontyCarter

src/Api/Memcache/Memcache.php

@@ -173,52 +173,56 @@ public function flush() {
  return true;
  }
 
- private function getMulti($keys, $flags = null) {
+ private function getMulti($keys, $flags = null, $for_peek = false) {
  $request = new MemcacheGetRequest();
  $response = new MemcacheGetResponse();
 
+ if ($for_peek) {
+ $request->setForPeek(true);
+ }
+
  foreach ($keys as $key) {
  $request->addKey($key);
  }
 
- ApiProxy::makeSyncCall('memcache', 'Get', $request, $response);
+ try {
+ ApiProxy::makeSyncCall('memcache', 'Get', $request, $response);
+ } catch (Error $e) {
+ return false;
+ }
 
  $return_value = array();
  foreach ($response->getItemList() as $item) {
  try {
- $return_value[$item->getKey()] = MemcacheUtils::deserializeValue(
- $item->getValue(), $item->getFlags());
+ $value = MemcacheUtils::deserializeValue($item->getValue(), $item->getFlags());
+ if ($for_peek) {
+ $memcacheItemWithTimestamps = new MemcacheItemWithTimestamps(
+ $value,
+ $item->getTimestamps()->getExpirationTimeSec(),
+ $item->getTimestamps()->getLastAccessTimeSec(),
+ $item->getTimestamps()->getDeleteLockTimeSec());
+ $return_value[$item->getKey()] = $memcacheItemWithTimestamps;
+ } else {
+ $return_value[$item->getKey()] = $value;
+ }
  } catch (\UnexpectedValueException $e) {
  // Skip entries that cannot be deserialized.
  }
  }
  return $return_value;
  }
 
- /**
- * Fetches previously stored data from the cache.
- *
- * @param string|string[] $keys The key associated with the value to fetch, or
- * an array of keys if fetching multiple values.
- *
- * @param int $flags This parameter is present only for compatibility and is
- * ignored. It should return the stored flag value.
- *
- * @return mixed On success, the string associated with the key, or an array
- * of key-value pairs when $keys is an array. On failure, false
- * is returned.
- */
- public function get($keys, $flags = null) {
+ private function getInternal($keys, $flags, $for_peek) {
  if (is_array($keys)) {
- $return_value = $this->getMulti($keys, $flags);
+ $return_value = $this->getMulti($keys, $flags, $for_peek);
  if (empty($return_value)) {
  return false;
  } else {
  return $return_value;
  }
  } else {
  try {
- $return_value = $this->getMulti(array($keys), array($flags));
+ $return_value = $this->getMulti(array($keys), array($flags), $for_peek);
  } catch (Error $e) {
  return false;
  }
@@ -230,6 +234,23 @@ public function get($keys, $flags = null) {
  }
  }
 
+ /**
+ * Fetches previously stored data from the cache.
+ *
+ * @param string|string[] $keys The key associated with the value to fetch, or
+ * an array of keys if fetching multiple values.
+ *
+ * @param int $flags This parameter is present only for compatibility and is
+ * ignored. It should return the stored flag value.
+ *
+ * @return mixed On success, the string associated with the key, or an array
+ * of key-value pairs when $keys is an array. On failure, false
+ * is returned.
+ */
+ public function get($keys, $flags = null) {
+ return $this->getInternal($keys, $flags, false /* $for_peek */);
+ }
+
  // Not implemented:
  // getExtendedStats
  // getServerStatus
@@ -296,6 +317,23 @@ public function pconnect($host, $port = null, $timeout = 1) {
  return true;
  }
 
+ /**
+ * Gets an item from memcache along with timestamp metadata.
+ *
+ * @param string|string[] $keys The key associated with the value to fetch, or
+ * an array of keys if fetching multiple values.
+ *
+ * @param int $flags This parameter is present only for compatibility and is
+ * ignored. It should return the stored flag value.
+ *
+ * @return mixed On success, the MemcacheItemWithTimestamps associated with
+ * the key, or an array of key-MemcacheItemWithTimestamp pairs
+ * when $keys is an array. On failure, false is returned.
+ */
+ public function peek($keys, $flags = null) {
+ return $this->getInternal($keys, $flags, true /* $for_peek */);
+ }
+
  /**
  * Replaces an existing item in the cache. Will fail if the key is not already
  * present in the cache.

src/Api/Memcache/MemcacheItemWithTimestamps.php

@@ -0,0 +1,62 @@
+<?php
+/**
+ * A memcache item with a value and timestamps.
+ */
+
+namespace Google\AppEngine\Api\Memcache;
+
+class MemcacheItemWithTimestamps {
+
+ private $value = null;
+ private $expiration_time_sec = null;
+ private $last_access_time_sec = null;
+ private $delete_lock_time_sec = null;
+
+ /**
+ * Constructs an instance of MemcacheItemWithTimestamps.
+ * @param mixed $value The value of the item.
+ * @param int $expirationTimeSec The absolute expiration time of the item.
+ * @param int $lastAccessTimeSec The absolute last access time of the item.
+ * @param int $deleteLockTimeSec The absolute delete lock time of the item.
+ */
+ public function __construct($value,
+ $expirationTimeSec,
+ $lastAccessTimeSec,
+ $deleteLockTimeSec) {
+ $this->value = $value;
+ $this->expiration_time_sec = $expirationTimeSec;
+ $this->last_access_time_sec = $lastAccessTimeSec;
+ $this->delete_lock_time_sec = $deleteLockTimeSec;
+ }
+
+ /**
+ * @return mixed The value of the item is returned.
+ */
+ public function getValue() {
+ return $this->value;
+ }
+
+ /**
+ * @return int Absolute expiration timestamp of the item in unix epoch seconds.
+ * Returns 0 if this item has no expiration timestamp.
+ */
+ public function getExpirationTimeSec() {
+ return $this->expiration_time_sec;
+ }
+
+ /**
+ * @return int Absolute last accessed timestamp of the item in unix epoch
+ * seconds.
+ */
+ public function getLastAccessTimeSec() {
+ return $this->last_access_time_sec;
+ }
+
+ /**
+ * @return int Absolute delete_time timestamp of the item in unix epoch
+ * seconds. Returns 0 if this item has no expiration timestamp.
+ */
+ public function getDeleteLockTimeSec() {
+ return $this->delete_lock_time_sec;
+ }
+}

src/Api/Memcache/MemcacheOptIn.php

@@ -219,6 +219,29 @@ function memcache_pconnect($host, $port = null, $timeout = 1) {
  }
 }
 
+/**
+ * Gets an item from memcache along with timestamp metadata.
+ *
+ * @param Memcache $memcache_obj The cache instance to get the item from.
+ *
+ * @param string|string[] $keys The key associated with the value to fetch, or
+ * an array of keys if fetching multiple values.
+ *
+ * @param int $flags This parameter is present only for compatibility and is
+ * ignored. It should return the stored flag value.
+ *
+ * @return mixed On success, the MemcacheItemWithTimestamps associated with the
+ * key, or an array of key-ItemWithTimestamp pairs when $keys is
+ * an array. On failure, false is returned.
+ */
+function memcache_peek(
+ Google\AppEngine\Api\Memcache\Memcache $memcache_obj,
+ $keys,
+ $flags = null
+) {
+ return $memcache_obj->peek($keys, $flags);
+}
+
 /**
  * Replaces an existing item in the cache. Will fail if the key is not already
  * present in the cache.