/**
* A general DHT class
*
- * @author Roland Haeder <webmaster@ship-simu.org>
+ * @author Roland Haeder <webmaster@shipsimu.org>
* @version 0.0.0
* @copyright Copyright (c) 2007, 2008 Roland Haeder, 2009 - 2012 Hub Developer Team
* @license GNU GPL 3.0 or any newer version
- * @link http://www.ship-simu.org
+ * @link http://www.shipsimu.org
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
-class BaseDht extends BaseHubSystem {
+abstract class BaseDht extends BaseHubSystem implements Distributable {
+ /**
+ * "Cached" instance of a publish helper
+ */
+ private $publishHelperInstance = NULL;
+
+ /**
+ * Stacker name for "INSERT" node data
+ */
+ const STACKER_NAME_INSERT_NODE = 'dht_insert_node';
+ const STACKER_NAME_PENDING_PUBLISHING = 'dht_pending_publish';
+
/**
* Protected constructor
*
protected function __construct ($className) {
// Call parent constructor
parent::__construct($className);
+
+ // Get a stacker instance for this DHT
+ $stackerInstance = ObjectFactory::createObjectByConfiguredName('dht_stacker_class');
+
+ // Set it in this class
+ $this->setStackerInstance($stackerInstance);
+
+ // Init all stackers
+ $this->initStacks();
+
+ /*
+ * Get the state factory and create the initial state, we don't need
+ * the state instance here
+ */
+ DhtStateFactory::createDhtStateInstanceByName('init', $this);
+ }
+
+ /**
+ * Initializes all stackers
+ *
+ * @return void
+ */
+ private function initStacks () {
+ // Initialize all stacker
+ $this->getStackerInstance()->initStacks(array(
+ self::STACKER_NAME_INSERT_NODE,
+ self::STACKER_NAME_PENDING_PUBLISHING,
+ ));
+ }
+
+ /**
+ * Registers/updates an entry in the DHT with given data from $dhtData
+ * array. Different DHT implemtations may handle this differently as they
+ * may enrich the data with more meta data.
+ *
+ * @param $dhtData A valid array with DHT-related data (e.g. node/peer data)
+ * @return void
+ */
+ protected abstract function insertDataIntoDht (array $dhtData);
+
+ /**
+ * Updates/refreshes DHT data (e.g. status).
+ *
+ * @return void
+ * @todo Find more to do here
+ */
+ public function updateDhtData () {
+ // Set some dummy configuration entries, e.g. dht_status
+ $this->getConfigInstance()->setConfigEntry('dht_status', $this->getStateInstance()->getStateName());
+ }
+
+ /**
+ * Checks whether there are entries in "INSERT" node data stack
+ *
+ * @return $isPending Whether there are pending entries
+ */
+ public function ifInsertNodeDataPending () {
+ // Determine it if it is not empty
+ $isPending = ($this->getStackerInstance()->isStackEmpty(self::STACKER_NAME_INSERT_NODE) === FALSE);
+
+ // Return status
+ return $isPending;
+ }
+
+ /**
+ * Inserts a single entry of node data into the DHT
+ *
+ * @return void
+ */
+ public function insertSingleNodeData () {
+ // Get next node data from stack
+ $nodeData = $this->getStackerInstance()->popNamed(self::STACKER_NAME_INSERT_NODE);
+
+ // Make sure $nodeData is really an array and has at least one entry
+ assert((is_array($nodeData)) && (count($nodeData) > 0));
+
+ // Insert the data
+ $this->insertDataIntoDht($nodeData);
+ }
+
+ /**
+ * Checks whether there are unpublished entries
+ *
+ * @return $hasUnpublished Whether there are unpublished entries
+ * @todo Add minimum/maximum age limitations
+ */
+ public function hasUnpublishedEntries () {
+ // Call method on database wrapper
+ $hasUnpublished = $this->getWrapperInstance()->hasUnpublishedEntries();
+
+ // Return it
+ return $hasUnpublished;
+ }
+
+ /**
+ * Initializes publication of DHT entries. This does only prepare
+ * publication. The next step is to pickup such prepared entries and publish
+ * them by uploading to other (recently appeared) DHT members.
+ *
+ * @return void
+ */
+ public function initEntryPublication () {
+ // Call method on database wrapper
+ $this->getWrapperInstance()->initEntryPublication();
+
+ // Get result instance
+ $resultInstance = $this->getWrapperInstance()->getUnpublishedEntriesInstance();
+
+ // Make sure the result instance is valid
+ assert($resultInstance instanceof SearchableResult);
+ assert($resultInstance->valid());
+
+ // "Walk" through all entries
+ while ($resultInstance->next()) {
+ // Get current entry
+ $current = $resultInstance->current();
+
+ // Make sure only valid entries pass
+ // @TODO Maybe add more small checks?
+ assert(is_array($current));
+
+ // ... and push it to the next stack
+ //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('BASE-DHT[' . __METHOD__ . ':' . __LINE__ . '] Pushing entry with ' . count($current) . ' elements to stack ' . self::STACKER_NAME_PENDING_PUBLISHING . ' ...');
+ $this->getStackerInstance()->pushNamed(self::STACKER_NAME_PENDING_PUBLISHING, $current);
+ } // END - while
+ }
+
+ /**
+ * Checks whether there are entries pending publication
+ *
+ * @return $isPending Whether there are entries pending publication
+ */
+ public function hasEntriesPendingPublication () {
+ // Determine it if it is not empty
+ $isPending = ($this->getStackerInstance()->isStackEmpty(self::STACKER_NAME_PENDING_PUBLISHING) === FALSE);
+
+ // Return status
+ /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('BASE-DHT[' . __METHOD__ . ':' . __LINE__ . '] isPending=' . intval($isPending));
+ return $isPending;
+ }
+
+ /**
+ * Whether this DHT's state is 'booting'
+ *
+ * @return $isBooting Whether this DHT is currently booting
+ */
+ public function ifDhtIsBooting () {
+ // Call state instance
+ $isBooting = $this->getStateInstance()->ifDhtIsBooting();
+
+ // Return status
+ /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('BASE-DHT[' . __METHOD__ . ':' . __LINE__ . '] isBooting=' . intval($isBooting));
+ return $isBooting;
+ }
+
+ /**
+ * Publishes next entry found in stack. This method shall also update the
+ * corresponding dabase entry.
+ *
+ * @return void
+ * @todo Find out if loadDescriptorXml() can be called only once to avoid a lot methods working.
+ */
+ public function publishEntry () {
+ // This test must not fail
+ assert($this->hasEntriesPendingPublication());
+
+ // Is there an instance?
+ if (!$this->publishHelperInstance instanceof HelpableDht) {
+ // Get a helper instance
+ $this->publishHelperInstance = ObjectFactory::createObjectByConfiguredName('dht_publish_entry_helper_class');
+ } // END - if
+
+ // Load the announcement descriptor
+ $this->publishHelperInstance->loadDescriptorXml($this);
+
+ // "Pop" next entry
+ $entry = $this->getStackerInstance()->popNamed(self::STACKER_NAME_PENDING_PUBLISHING);
+
+ // Some sanity-checks
+ assert(is_array($entry));
+
+ // Remove any non-public data the database layer desires
+ //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('DHT[' . __METHOD__ . ':' . __LINE__ . ']: Calling this->getWrapperInstance()->removeNonPublicDataFromArray(data) ...');
+ $entry = $this->getWrapperInstance()->removeNonPublicDataFromArray($entry);
+ //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('DHT[' . __METHOD__ . ':' . __LINE__ . ']: entry[]=' . gettype($entry));
+
+ // Some sanity-checks again
+ assert(is_array($entry));
+
+ // Inject variables
+ $this->publishHelperInstance->getTemplateInstance()->injectConfigVariables($entry);
+
+ // "Publish" the descriptor by sending it to the bootstrap/list nodes
+ $this->publishHelperInstance->sendPackage($this);
+ }
+
+ /**
+ * Whether the DHT has fully bootstrapped (after state 'booting')
+ *
+ * @return $isFullyBooted Whether the DHT is fully booted
+ * @todo 0% done
+ */
+ public function hasFullyBootstrapped () {
+ // Get state and check it
+ $this->partialStub('Please implement this method.');
+ }
+
+ /**
+ * Enable DHT bootstrap request acceptance for local node
+ *
+ * @return void
+ * @todo Switch flag 'accept_bootstrap'
+ */
+ public function enableAcceptDhtBootstrap () {
+ // Call method on database wrapper
+ $this->getWrapperInstance()->enableAcceptDhtBootstrap();
}
}
projects / hub.git / blobdiff