/**
* @param array $cacheKeys
* @param callable $loadCallback
* @return array
*/
public function getByKey(array $cacheKeys, $loadCallback)
{
if (!$cacheKeys) {
return array();
}
$result = array();
$multiRes = $this->cache->getMulti(array_keys($cacheKeys));
if ($multiRes === false) {
// Falls through to query only backend
wfDebugLog('Flow', __METHOD__ . ': Failure querying memcache');
} else {
// Memcached BagOStuff only returns found keys, but the redis bag
// returns false for not found keys.
$multiRes = array_filter($multiRes, function ($val) {
return $val !== false;
});
foreach ($multiRes as $key => $value) {
$idx = $cacheKeys[$key];
if ($idx instanceof UUID) {
$idx = $idx->getAlphadecimal();
}
$result[$idx] = $value;
unset($cacheKeys[$key]);
}
}
if (count($cacheKeys) === 0) {
return $result;
}
$res = call_user_func($loadCallback, array_values($cacheKeys));
if (!$res) {
// storage failure of some sort
return $result;
}
$invCacheKeys = array();
foreach ($cacheKeys as $cacheKey => $id) {
if ($id instanceof UUID) {
$id = $id->getAlphadecimal();
}
$invCacheKeys[$id] = $cacheKey;
}
foreach ($res as $id => $row) {
// If we failed contacting memcache a moment ago don't bother trying to
// push values either.
if ($multiRes !== false) {
$this->cache->set($invCacheKeys[$id], $row);
}
$result[$id] = $row;
}
return $result;
}
/**
* @expectedException \Flow\Exception\DataModelException
*/
public function testFailingInsert()
{
global $wgFlowCacheTime;
// Catch the exception and test the cache result then re-throw the exception,
// otherwise the exception would skip the cache result test
$cache = new BufferedCache(new BufferedBagOStuff(new \HashBagOStuff()), $wgFlowCacheTime);
try {
$treeRepository = new TreeRepository($this->mockDbFactory(false), $cache);
$this->assertNull($treeRepository->insert($this->descendant, $this->ancestor));
} catch (\Exception $e) {
$reflection = new ReflectionClass('\\Flow\\Repository\\TreeRepository');
$method = $reflection->getMethod('cacheKey');
$method->setAccessible(true);
$this->assertSame($cache->get($method->invoke($treeRepository, 'rootpath', $this->descendant)), false);
$this->assertSame($cache->get($method->invoke($treeRepository, 'parent', $this->descendant)), false);
throw $e;
}
}
/**
* Given a list of nodes, find the path from each node to the root of its tree.
* the root must be the first element of the array, $node must be the last element.
* @param UUID[] $descendants Array of UUID objects to find the root paths for.
* @return UUID[][] Associative array, key is the post ID in hex, value is the path as an array.
*/
public function findRootPaths(array $descendants)
{
// alphadecimal => cachekey
$cacheKeys = array();
// alphadecimal => cache result ( distance => parent uuid obj )
$cacheValues = array();
// list of binary values for db query
$missingValues = array();
// alphadecimal => distance => parent uuid obj
$paths = array();
foreach ($descendants as $descendant) {
$cacheKeys[$descendant->getAlphadecimal()] = $this->cacheKey('rootpath', $descendant);
}
$cacheResult = $this->cache->getMulti(array_values($cacheKeys));
foreach ($descendants as $descendant) {
$alpha = $descendant->getAlphadecimal();
if (isset($cacheResult[$cacheKeys[$alpha]])) {
$cacheValues[$alpha] = $cacheResult[$cacheKeys[$alpha]];
} else {
$missingValues[] = $descendant->getBinary();
$paths[$alpha] = array();
}
}
if (!count($missingValues)) {
return $cacheValues;
}
$dbr = $this->dbFactory->getDB(DB_SLAVE);
$res = $dbr->select($this->tableName, array('tree_descendant_id', 'tree_ancestor_id', 'tree_depth'), array('tree_descendant_id' => $missingValues), __METHOD__);
if (!$res || $res->numRows() === 0) {
return $cacheValues;
}
foreach ($res as $row) {
$alpha = UUID::create($row->tree_descendant_id)->getAlphadecimal();
$paths[$alpha][$row->tree_depth] = UUID::create($row->tree_ancestor_id);
}
foreach ($paths as $descendantId => &$path) {
if (!$path) {
$path = null;
continue;
}
// sort by reverse distance, so furthest away
// parent (root) is at position 0.
ksort($path);
$path = array_reverse($path);
$this->cache->set($cacheKeys[$descendantId], $path);
}
return $paths + $cacheValues;
}
/**
* Returns a boolean true/false if the findMulti()-operation for the given
* attributes has already been resolves and doesn't need to query any
* outside cache/database.
* Determining if a find() has not yet been resolved may be useful so that
* additional data may be loaded at once.
*
* @param array $queries Queries to findMulti()
* @param array[optional] $options Options to findMulti()
* @return bool
*/
public function foundMulti(array $queries, array $options = array())
{
if (!$queries) {
return true;
}
// get cache keys for all queries
$cacheKeys = $this->getCacheKeys($queries);
// check if cache has a way of identifying what's stored locally
if (!method_exists($this->cache, 'has')) {
return false;
}
// check if keys matching given queries are already known in local cache
foreach ($cacheKeys as $key) {
if (!$this->cache->has($key)) {
return false;
}
}
$keyToQuery = array();
foreach ($cacheKeys as $i => $key) {
// These results will be merged into the query results, and as such need binary
// uuid's as would be received from storage
if (!isset($keyToQuery[$key])) {
$keyToQuery[$key] = $queries[$i];
}
}
// retrieve from cache - this is cheap, it's is local storage
$cached = $this->cache->getMulti($cacheKeys);
foreach ($cached as $i => $result) {
$limit = isset($options['limit']) ? $options['limit'] : $this->getLimit();
$cached[$i] = array_splice($result, 0, $limit);
}
// if we have a shallow compactor, the returned data are PKs of objects
// that need to be fetched too
if ($this->rowCompactor instanceof ShallowCompactor) {
// test of the keys to be expanded are already in local cache
$duplicator = $this->rowCompactor->getResultDuplicator($cached, $keyToQuery);
$queries = $duplicator->getUniqueQueries();
if (!$this->rowCompactor->getShallow()->foundMulti($queries)) {
return false;
}
}
return true;
}
