application/hub/main/package/class_NetworkPackage.php

   1 <?php
   2 /**
   3  * A NetworkPackage class. This class implements Deliverable and Receivable
   4  * because all network packages should be deliverable to other nodes and
   5  * receivable from other nodes. It further provides methods for reading raw
   6  * content from template engines and feeding it to the stacker for undeclared
   7  * packages.
   8  *
   9  * The factory method requires you to provide a compressor class (which must
  10  * implement the Compressor interface). If you don't want any compression (not
  11  * adviceable due to increased network load), please use the NullCompressor
  12  * class and encode it with BASE64 for a more error-free transfer over the
  13  * Internet.
  14  *
  15  * For performance reasons, this class should only be instanciated once and then
  16  * used as a "pipe-through" class.
  17  *
  18  * @author              Roland Haeder <webmaster@ship-simu.org>
  19  * @version             0.0.0
  20  * @copyright   Copyright (c) 2007, 2008 Roland Haeder, 2009 - 2011 Hub Developer Team
  21  * @license             GNU GPL 3.0 or any newer version
  22  * @link                http://www.ship-simu.org
  23  * @todo                Needs to add functionality for handling the object's type
  24  *
  25  * This program is free software: you can redistribute it and/or modify
  26  * it under the terms of the GNU General Public License as published by
  27  * the Free Software Foundation, either version 3 of the License, or
  28  * (at your option) any later version.
  29  *
  30  * This program is distributed in the hope that it will be useful,
  31  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  32  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  33  * GNU General Public License for more details.
  34  *
  35  * You should have received a copy of the GNU General Public License
  36  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  37  */
  38 class NetworkPackage extends BaseHubSystem implements Deliverable, Receivable, Registerable, Visitable {
  39         /**
  40          * Package mask for compressing package data:
  41          * 0: Compressor extension
  42          * 1: Raw package data
  43          * 2: Tags, seperated by semicolons, no semicolon is required if only one tag is needed
  44          * 3: Checksum
  45          *                     0  1  2  3
  46          */
  47         const PACKAGE_MASK = '%s%s%s%s%s%s%s';
  48
  49         /**
  50          * Separator for the above mask
  51          */
  52         const PACKAGE_MASK_SEPARATOR = '^';
  53
  54         /**
  55          * SEPARATOR for checksum
  56          */
  57         const PACKAGE_CHECKSUM_SEPARATOR = '_';
  58
  59         /**
  60          * Array indexes for above mask, start with zero
  61          */
  62         const INDEX_COMPRESSOR_EXTENSION = 0;
  63         const INDEX_PACKAGE_DATA         = 1;
  64         const INDEX_TAGS                 = 2;
  65         const INDEX_CHECKSUM             = 3;
  66
  67         /**
  68          * Array indexes for raw package array
  69          */
  70         const INDEX_PACKAGE_SENDER    = 0;
  71         const INDEX_PACKAGE_RECIPIENT = 1;
  72         const INDEX_PACKAGE_CONTENT   = 2;
  73         const INDEX_PACKAGE_STATUS    = 3;
  74         const INDEX_PACKAGE_SIGNATURE = 4;
  75
  76         /**
  77          * Named array elements for package data
  78          */
  79         const PACKAGE_DATA_SENDER    = 'sender';
  80         const PACKAGE_DATA_RECIPIENT = 'recipient';
  81         const PACKAGE_DATA_CONTENT   = 'content';
  82         const PACKAGE_DATA_STATUS    = 'status';
  83         const PACKAGE_DATA_SIGNATURE = 'signature';
  84
  85         /**
  86          * All package status
  87          */
  88         const PACKAGE_STATUS_NEW     = 'new';
  89         const PACKAGE_STATUS_FAILED  = 'failed';
  90         const PACKAGE_STATUS_DECODED = 'decoded';
  91
  92         /**
  93          * Tags separator
  94          */
  95         const PACKAGE_TAGS_SEPARATOR = ';';
  96
  97         /**
  98          * Raw package data separator
  99          */
 100         const PACKAGE_DATA_SEPARATOR = '#';
 101
 102         /**
 103          * Network target (alias): 'upper hubs'
 104          */
 105         const NETWORK_TARGET_UPPER_HUBS = 'upper';
 106
 107         /**
 108          * Network target (alias): 'self'
 109          */
 110         const NETWORK_TARGET_SELF = 'self';
 111
 112         /**
 113          * TCP package size in bytes
 114          */
 115         const TCP_PACKAGE_SIZE = 512;
 116
 117         /**
 118          * Size of the decoded data array
 119          */
 120         const DECODED_DATA_ARRAY_SIZE = 4;
 121
 122         /**************************************************************************
 123          *                    Stacker for out-going packages                      *
 124          **************************************************************************/
 125
 126         /**
 127          * Stacker name for "undeclared" packages
 128          */
 129         const STACKER_NAME_UNDECLARED = 'package_undeclared';
 130
 131         /**
 132          * Stacker name for "declared" packages (which are ready to send out)
 133          */
 134         const STACKER_NAME_DECLARED = 'package_declared';
 135
 136         /**
 137          * Stacker name for "out-going" packages
 138          */
 139         const STACKER_NAME_OUTGOING = 'package_outgoing';
 140
 141         /**************************************************************************
 142          *                     Stacker for incoming packages                      *
 143          **************************************************************************/
 144
 145         /**
 146          * Stacker name for "incoming" decoded raw data
 147          */
 148         const STACKER_NAME_DECODED_INCOMING = 'package_decoded_data';
 149
 150         /**
 151          * Stacker name for handled decoded raw data
 152          */
 153         const STACKER_NAME_DECODED_HANDLED = 'package_handled_decoded';
 154
 155         /**
 156          * Stacker name for "chunked" decoded raw data
 157          */
 158         const STACKER_NAME_DECODED_CHUNKED = 'package_chunked_decoded';
 159
 160         /**************************************************************************
 161          *                   Stacker for other/internal purposes                  *
 162          **************************************************************************/
 163
 164         /**
 165          * Stacker name for "back-buffered" packages
 166          */
 167         const STACKER_NAME_BACK_BUFFER = 'package_backbuffer';
 168
 169         /**
 170          * Protected constructor
 171          *
 172          * @return      void
 173          */
 174         protected function __construct () {
 175                 // Call parent constructor
 176                 parent::__construct(__CLASS__);
 177         }
 178
 179         /**
 180          * Creates an instance of this class
 181          *
 182          * @param       $compressorInstance             A Compressor instance for compressing the content
 183          * @return      $packageInstance                An instance of a Deliverable class
 184          */
 185         public static final function createNetworkPackage (Compressor $compressorInstance) {
 186                 // Get new instance
 187                 $packageInstance = new NetworkPackage();
 188
 189                 // Now set the compressor instance
 190                 $packageInstance->setCompressorInstance($compressorInstance);
 191
 192                 /*
 193                  * We need to initialize a stack here for our packages even for those
 194                  * which have no recipient address and stamp... ;-) This stacker will
 195                  * also be used for incoming raw data to handle it.
 196                  */
 197                 $stackerInstance = ObjectFactory::createObjectByConfiguredName('network_package_stacker_class');
 198
 199                 // At last, set it in this class
 200                 $packageInstance->setStackerInstance($stackerInstance);
 201
 202                 // Init all stacker
 203                 $packageInstance->initStackers();
 204
 205                 // Get a visitor instance for speeding up things
 206                 $visitorInstance = ObjectFactory::createObjectByConfiguredName('node_raw_data_monitor_visitor_class', array($packageInstance));
 207
 208                 // Set it in this package
 209                 $packageInstance->setVisitorInstance($visitorInstance);
 210
 211                 // Get crypto instance and set it in this package
 212                 $cryptoInstance = ObjectFactory::createObjectByConfiguredName('crypto_class');
 213                 $packageInstance->setCryptoInstance($cryptoInstance);
 214
 215                 // Get a singleton package assembler instance from factory and set it here
 216                 $assemblerInstance = PackageAssemblerFactory::createAssemblerInstance($packageInstance);
 217                 $packageInstance->setAssemblerInstance($assemblerInstance);
 218
 219                 // Return the prepared instance
 220                 return $packageInstance;
 221         }
 222
 223         /**
 224          * Initialize all stackers
 225          *
 226          * @param       $forceReInit    Whether to force reinitialization of all stacks
 227          * @return      void
 228          */
 229         protected function initStackers ($forceReInit = false) {
 230                 // Initialize all
 231                 foreach (
 232                         array(
 233                                 self::STACKER_NAME_UNDECLARED,
 234                                 self::STACKER_NAME_DECLARED,
 235                                 self::STACKER_NAME_OUTGOING,
 236                                 self::STACKER_NAME_DECODED_INCOMING,
 237                                 self::STACKER_NAME_DECODED_HANDLED,
 238                                 self::STACKER_NAME_DECODED_CHUNKED,
 239                                 self::STACKER_NAME_BACK_BUFFER
 240                         ) as $stackerName) {
 241                                 // Init this stacker
 242                                 $this->getStackerInstance()->initStacker($stackerName, $forceReInit);
 243                 } // END - foreach
 244         }
 245
 246         /**
 247          * "Getter" for hash from given content and helper instance
 248          *
 249          * @param       $content                        Raw package content
 250          * @param       $helperInstance         An instance of a HelpableHub class
 251          * @param       $nodeInstance           An instance of a NodeHelper class
 252          * @return      $hash                           Hash for given package content
 253          */
 254         private function getHashFromContent ($content) {
 255                 // Create the hash
 256                 // @TODO crc32() is very weak, but it needs to be fast
 257                 $hash = crc32(
 258                         $content .
 259                         self::PACKAGE_CHECKSUM_SEPARATOR .
 260                         $this->getSessionId() .
 261                         self::PACKAGE_CHECKSUM_SEPARATOR .
 262                         $this->getCompressorInstance()->getCompressorExtension()
 263                 );
 264
 265                 // And return it
 266                 return $hash;
 267         }
 268
 269         /**
 270          * Change the package with given status in given stack
 271          *
 272          * @param       $packageData    Raw package data in an array
 273          * @param       $stackerName    Name of the stacker
 274          * @param       $newStatus              New status to set
 275          * @return      void
 276          */
 277         private function changePackageStatus (array $packageData, $stackerName, $newStatus) {
 278                 // Skip this for empty stacks
 279                 if ($this->getStackerInstance()->isStackEmpty($stackerName)) {
 280                         // This avoids an exception after all packages has failed
 281                         return;
 282                 } // END - if
 283
 284                 // Pop the entry (it should be it)
 285                 $nextData = $this->getStackerInstance()->popNamed($stackerName);
 286
 287                 // Compare both arrays
 288                 assert($nextData[self::PACKAGE_DATA_SIGNATURE] == $packageData[self::PACKAGE_DATA_SIGNATURE]);
 289
 290                 // Temporary set the new status
 291                 $packageData[self::PACKAGE_DATA_STATUS] = $newStatus;
 292
 293                 // And push it again
 294                 $this->getStackerInstance()->pushNamed($stackerName, $packageData);
 295         }
 296
 297         ///////////////////////////////////////////////////////////////////////////
 298         //                   Delivering packages / raw data
 299         ///////////////////////////////////////////////////////////////////////////
 300
 301         /**
 302          * Delivers the given raw package data.
 303          *
 304          * @param       $packageData    Raw package data in an array
 305          * @return      void
 306          */
 307         private function declareRawPackageData (array $packageData) {
 308                 /*
 309                  * We need to disover every recipient, just in case we have a
 310                  * multi-recipient entry like 'upper' is. 'all' may be a not so good
 311                  * target because it causes an overload on the network and may be
 312                  * abused for attacking the network with large packages.
 313                  */
 314                 $discoveryInstance = PackageDiscoveryFactory::createPackageDiscoveryInstance();
 315
 316                 // Discover all recipients, this may throw an exception
 317                 $discoveryInstance->discoverRecipients($packageData);
 318
 319                 // Now get an iterator
 320                 $iteratorInstance = $discoveryInstance->getIterator();
 321
 322                 // Rewind back to the beginning
 323                 $iteratorInstance->rewind();
 324
 325                 // ... and begin iteration
 326                 while ($iteratorInstance->valid()) {
 327                         // Get current entry
 328                         $currentRecipient = $iteratorInstance->current();
 329
 330                         // Set the recipient
 331                         $packageData[self::PACKAGE_DATA_RECIPIENT] = $currentRecipient;
 332
 333                         // And enqueue it to the writer class
 334                         $this->getStackerInstance()->pushNamed(self::STACKER_NAME_DECLARED, $packageData);
 335
 336                         // Debug message
 337                         $this->debugOutput('PACKAGE: Package declared for recipient ' . $currentRecipient);
 338
 339                         // Skip to next entry
 340                         $iteratorInstance->next();
 341                 } // END - while
 342
 343                 /*
 344                  * The recipient list can be cleaned up here because the package which
 345                  * shall be delivered has already been added for all entries from the
 346                  * list.
 347                  */
 348                 $discoveryInstance->clearRecipients();
 349         }
 350
 351         /**
 352          * Delivers raw package data. In short, this will discover the raw socket
 353          * resource through a discovery class (which will analyse the receipient of
 354          * the package), register the socket with the connection (handler/helper?)
 355          * instance and finally push the raw data on our outgoing queue.
 356          *
 357          * @param       $packageData    Raw package data in an array
 358          * @return      void
 359          */
 360         private function deliverRawPackageData (array $packageData) {
 361                 /*
 362                  * This package may become big, depending on the shared object size or
 363                  * delivered message size which shouldn't be so long (to save
 364                  * bandwidth). Because of the nature of the used protocol (TCP) we need
 365                  * to split it up into smaller pieces to fit it into a TCP frame.
 366                  *
 367                  * So first we need (again) a discovery class but now a protocol
 368                  * discovery to choose the right socket resource. The discovery class
 369                  * should take a look at the raw package data itself and then decide
 370                  * which (configurable!) protocol should be used for that type of
 371                  * package.
 372                  */
 373                 $discoveryInstance = SocketDiscoveryFactory::createSocketDiscoveryInstance();
 374
 375                 // Now discover the right protocol
 376                 $socketResource = $discoveryInstance->discoverSocket($packageData);
 377
 378                 // Debug message
 379                 //* NOISY-DEBUG: */ $this->debugOutput('PACKAGE: Reached line ' . __LINE__ . ' after discoverSocket() has been called.');
 380
 381                 // We have to put this socket in our registry, so get an instance
 382                 $registryInstance = SocketRegistry::createSocketRegistry();
 383
 384                 // Get the listener from registry
 385                 $helperInstance = Registry::getRegistry()->getInstance('connection');
 386
 387                 // Debug message
 388                 //* NOISY-DEBUG: */ $this->debugOutput('PACKAGE: stateInstance=' . $helperInstance->getStateInstance());
 389                 //* NOISY-DEBUG: */ $this->debugOutput('PACKAGE: Reached line ' . __LINE__ . ' before isSocketRegistered() has been called.');
 390
 391                 // Is it not there?
 392                 if ((is_resource($socketResource)) && (!$registryInstance->isSocketRegistered($helperInstance, $socketResource))) {
 393                         // Debug message
 394                         $this->debugOutput('PACKAGE: Registering socket ' . $socketResource . ' ...');
 395
 396                         // Then register it
 397                         $registryInstance->registerSocket($helperInstance, $socketResource, $packageData);
 398                 } elseif (!$helperInstance->getStateInstance()->isPeerStateConnected()) {
 399                         // Is not connected, then we cannot send
 400                         $this->debugOutput('PACKAGE: Unexpected peer state ' . $helperInstance->getStateInstance()->__toString() . ' detected.');
 401
 402                         // Shutdown the socket
 403                         $this->shutdownSocket($socketResource);
 404                 }
 405
 406                 // Debug message
 407                 //* NOISY-DEBUG: */ $this->debugOutput('PACKAGE: Reached line ' . __LINE__ . ' after isSocketRegistered() has been called.');
 408
 409                 // Make sure the connection is up
 410                 $helperInstance->getStateInstance()->validatePeerStateConnected();
 411
 412                 // Debug message
 413                 //* NOISY-DEBUG: */ $this->debugOutput('PACKAGE: Reached line ' . __LINE__ . ' after validatePeerStateConnected() has been called.');
 414
 415                 // Enqueue it again on the out-going queue, the connection is up and working at this point
 416                 $this->getStackerInstance()->pushNamed(self::STACKER_NAME_OUTGOING, $packageData);
 417
 418                 // Debug message
 419                 //* NOISY-DEBUG: */ $this->debugOutput('PACKAGE: Reached line ' . __LINE__ . ' after pushNamed() has been called.');
 420         }
 421
 422         /**
 423          * Sends waiting packages
 424          *
 425          * @param       $packageData    Raw package data
 426          * @return      void
 427          */
 428         private function sendOutgoingRawPackageData (array $packageData) {
 429                 // Init sent bytes
 430                 $sentBytes = 0;
 431
 432                 // Get the right connection instance
 433                 $helperInstance = SocketRegistry::createSocketRegistry()->getHandlerInstanceFromPackageData($packageData);
 434
 435                 // Is this connection still alive?
 436                 if ($helperInstance->isShuttedDown()) {
 437                         // This connection is shutting down
 438                         // @TODO We may want to do somthing more here?
 439                         return;
 440                 } // END - if
 441
 442                 // Sent out package data
 443                 $sentBytes = $helperInstance->sendRawPackageData($packageData);
 444
 445                 // Remember unsent raw bytes in back-buffer, if any
 446                 $this->storeUnsentBytesInBackBuffer($packageData, $sentBytes);
 447         }
 448
 449         /**
 450          * Generates a signature for given raw package content and sender id
 451          *
 452          * @param       $content        Raw package data
 453          * @param       $senderId       Sender id to generate a signature for
 454          * @return      $signature      Signature as BASE64-encoded string
 455          */
 456         private function generatePackageSignature ($content, $senderId) {
 457                 // ash content and sender id together, use md5() as last algo
 458                 $hash = md5($this->getCryptoInstance()->hashString($senderId . $content, $this->getNodeId(), false));
 459
 460                 // Encrypt the content again with the hash as a key
 461                 $encryptedContent = $this->getCryptoInstance()->encryptString($content, $hash);
 462
 463                 // Encode it with BASE64
 464                 $signature = base64_encode($encryptedContent);
 465
 466                 // Return it
 467                 return $signature;
 468         }
 469
 470         /**
 471          * "Enqueues" raw content into this delivery class by reading the raw content
 472          * from given template instance and pushing it on the 'undeclared' stack.
 473          *
 474          * @param       $helperInstance         An instance of a HelpableHub class
 475          * @return      void
 476          */
 477         public function enqueueRawDataFromTemplate (HelpableHub $helperInstance) {
 478                 // Get the raw content ...
 479                 $content = $helperInstance->getTemplateInstance()->getRawTemplateData();
 480
 481                 // ... and compress it
 482                 $content = $this->getCompressorInstance()->compressStream($content);
 483
 484                 // Add magic in front of it and hash behind it, including BASE64 encoding
 485                 $content = sprintf(self::PACKAGE_MASK,
 486                         // 1.) Compressor's extension
 487                         $this->getCompressorInstance()->getCompressorExtension(),
 488                         // - separator
 489                         self::PACKAGE_MASK_SEPARATOR,
 490                         // 2.) Raw package content, encoded with BASE64
 491                         base64_encode($content),
 492                         // - separator
 493                         self::PACKAGE_MASK_SEPARATOR,
 494                         // 3.) Tags
 495                         implode(self::PACKAGE_TAGS_SEPARATOR, $helperInstance->getPackageTags()),
 496                         // - separator
 497                         self::PACKAGE_MASK_SEPARATOR,
 498                         // 4.) Checksum
 499                         $this->getHashFromContent($content)
 500                 );
 501
 502                 // Now prepare the temporary array and push it on the 'undeclared' stack
 503                 $this->getStackerInstance()->pushNamed(self::STACKER_NAME_UNDECLARED, array(
 504                         self::PACKAGE_DATA_SENDER    => $nodeInstance->getSessionId(),
 505                         self::PACKAGE_DATA_RECIPIENT => $helperInstance->getRecipientType(),
 506                         self::PACKAGE_DATA_CONTENT   => $content,
 507                         self::PACKAGE_DATA_STATUS    => self::PACKAGE_STATUS_NEW,
 508                         self::PACKAGE_DATA_SIGNATURE => $this->generatePackageSignature($content, $this->getSessionId())
 509                 ));
 510         }
 511
 512         /**
 513          * Checks whether a package has been enqueued for delivery.
 514          *
 515          * @return      $isEnqueued             Whether a package is enqueued
 516          */
 517         public function isPackageEnqueued () {
 518                 // Check whether the stacker is not empty
 519                 $isEnqueued = (($this->getStackerInstance()->isStackInitialized(self::STACKER_NAME_UNDECLARED)) && (!$this->getStackerInstance()->isStackEmpty(self::STACKER_NAME_UNDECLARED)));
 520
 521                 // Return the result
 522                 return $isEnqueued;
 523         }
 524
 525         /**
 526          * Checks whether a package has been declared
 527          *
 528          * @return      $isDeclared             Whether a package is declared
 529          */
 530         public function isPackageDeclared () {
 531                 // Check whether the stacker is not empty
 532                 $isDeclared = (($this->getStackerInstance()->isStackInitialized(self::STACKER_NAME_DECLARED)) && (!$this->getStackerInstance()->isStackEmpty(self::STACKER_NAME_DECLARED)));
 533
 534                 // Return the result
 535                 return $isDeclared;
 536         }
 537
 538         /**
 539          * Checks whether a package should be sent out
 540          *
 541          * @return      $isWaitingDelivery      Whether a package is waiting for delivery
 542          */
 543         public function isPackageWaitingForDelivery () {
 544                 // Check whether the stacker is not empty
 545                 $isWaitingDelivery = (($this->getStackerInstance()->isStackInitialized(self::STACKER_NAME_OUTGOING)) && (!$this->getStackerInstance()->isStackEmpty(self::STACKER_NAME_OUTGOING)));
 546
 547                 // Return the result
 548                 return $isWaitingDelivery;
 549         }
 550
 551         /**
 552          * Delivers an enqueued package to the stated destination. If a non-session
 553          * id is provided, recipient resolver is being asked (and instanced once).
 554          * This allows that a single package is being delivered to multiple targets
 555          * without enqueueing it for every target. If no target is provided or it
 556          * can't be determined a NoTargetException is being thrown.
 557          *
 558          * @return      void
 559          * @throws      NoTargetException       If no target can't be determined
 560          */
 561         public function declareEnqueuedPackage () {
 562                 // Make sure this method isn't working if there is no package enqueued
 563                 if (!$this->isPackageEnqueued()) {
 564                         // This is not fatal but should be avoided
 565                         // @TODO Add some logging here
 566                         return;
 567                 } // END - if
 568
 569                 // Now we know for sure there are packages to deliver, we can start
 570                 // with the first one.
 571                 $packageData = $this->getStackerInstance()->getNamed(self::STACKER_NAME_UNDECLARED);
 572
 573                 // Declare the raw package data for delivery
 574                 $this->declareRawPackageData($packageData);
 575
 576                 // And remove it finally
 577                 $this->getStackerInstance()->popNamed(self::STACKER_NAME_UNDECLARED);
 578         }
 579
 580         /**
 581          * Delivers the next declared package. Only one package per time will be sent
 582          * because this may take time and slows down the whole delivery
 583          * infrastructure.
 584          *
 585          * @return      void
 586          */
 587         public function deliverDeclaredPackage () {
 588                 // Sanity check if we have packages declared
 589                 if (!$this->isPackageDeclared()) {
 590                         // This is not fatal but should be avoided
 591                         $this->debugOutput('PACKAGE: No package has been declared, but ' . __METHOD__ . ' has been called!');
 592                         return;
 593                 } // END - if
 594
 595                 // Get the package
 596                 $packageData = $this->getStackerInstance()->getNamed(self::STACKER_NAME_DECLARED);
 597
 598                 try {
 599                         // And try to send it
 600                         $this->deliverRawPackageData($packageData);
 601
 602                         // And remove it finally
 603                         $this->getStackerInstance()->popNamed(self::STACKER_NAME_DECLARED);
 604                 } catch (InvalidStateException $e) {
 605                         // The state is not excepected (shall be 'connected')
 606                         $this->debugOutput('PACKAGE: Caught ' . $e->__toString() . ',message=' . $e->getMessage());
 607
 608                         // Mark the package with status failed
 609                         $this->changePackageStatus($packageData, self::STACKER_NAME_DECLARED, self::PACKAGE_STATUS_FAILED);
 610                 }
 611         }
 612
 613         /**
 614          * Sends waiting packages out for delivery
 615          *
 616          * @return      void
 617          */
 618         public function sendWaitingPackage () {
 619                 // Send any waiting bytes in the back-buffer before sending a new package
 620                 $this->sendBackBufferBytes();
 621
 622                 // Sanity check if we have packages waiting for delivery
 623                 if (!$this->isPackageWaitingForDelivery()) {
 624                         // This is not fatal but should be avoided
 625                         $this->debugOutput('PACKAGE: No package is waiting for delivery, but ' . __METHOD__ . ' was called.');
 626                         return;
 627                 } // END - if
 628
 629                 // Get the package
 630                 $packageData = $this->getStackerInstance()->getNamed(self::STACKER_NAME_OUTGOING);
 631
 632                 try {
 633                         // Now try to send it
 634                         $this->sendOutgoingRawPackageData($packageData);
 635
 636                         // And remove it finally
 637                         $this->getStackerInstance()->popNamed(self::STACKER_NAME_OUTGOING);
 638                 } catch (InvalidSocketException $e) {
 639                         // Output exception message
 640                         $this->debugOutput('PACKAGE: Package was not delivered: ' . $e->getMessage());
 641
 642                         // Mark package as failed
 643                         $this->changePackageStatus($packageData, self::STACKER_NAME_OUTGOING, self::PACKAGE_STATUS_FAILED);
 644                 }
 645         }
 646
 647         ///////////////////////////////////////////////////////////////////////////
 648         //                   Receiving packages / raw data
 649         ///////////////////////////////////////////////////////////////////////////
 650
 651         /**
 652          * Checks whether decoded raw data is pending
 653          *
 654          * @return      $isPending      Whether decoded raw data is pending
 655          */
 656         private function isDecodedDataPending () {
 657                 // Just return whether the stack is not empty
 658                 $isPending = (!$this->getStackerInstance()->isStackEmpty(self::STACKER_NAME_DECODED_INCOMING));
 659
 660                 // Return the status
 661                 return $isPending;
 662         }
 663
 664         /**
 665          * Checks whether new raw package data has arrived at a socket
 666          *
 667          * @param       $poolInstance   An instance of a PoolableListener class
 668          * @return      $hasArrived             Whether new raw package data has arrived for processing
 669          */
 670         public function isNewRawDataPending (PoolableListener $poolInstance) {
 671                 // Visit the pool. This monitors the pool for incoming raw data.
 672                 $poolInstance->accept($this->getVisitorInstance());
 673
 674                 // Check for new data arrival
 675                 $hasArrived = $this->isDecodedDataPending();
 676
 677                 // Return the status
 678                 return $hasArrived;
 679         }
 680
 681         /**
 682          * Handles the incoming decoded raw data. This method does not "convert" the
 683          * decoded data back into a package array, it just "handles" it and pushs it
 684          * on the next stack.
 685          *
 686          * @return      void
 687          */
 688         public function handleIncomingDecodedData () {
 689                 /*
 690                  * This method should only be called if decoded raw data is pending,
 691                  * so check it again.
 692                  */
 693                 if (!$this->isDecodedDataPending()) {
 694                         // This is not fatal but should be avoided
 695                         // @TODO Add some logging here
 696                         return;
 697                 } // END - if
 698
 699                 // Very noisy debug message:
 700                 /* NOISY-DEBUG: */ $this->debugOutput('PACKAGE: Stacker size is ' . $this->getStackerInstance()->getStackCount(self::STACKER_NAME_DECODED_INCOMING) . ' entries.');
 701
 702                 // "Pop" the next entry (the same array again) from the stack
 703                 $decodedData = $this->getStackerInstance()->popNamed(self::STACKER_NAME_DECODED_INCOMING);
 704
 705                 // Make sure both array elements are there
 706                 assert(
 707                         (is_array($decodedData)) &&
 708                         (isset($decodedData[BaseRawDataHandler::PACKAGE_DECODED_DATA])) &&
 709                         (isset($decodedData[BaseRawDataHandler::PACKAGE_ERROR_CODE]))
 710                 );
 711
 712                 /*
 713                  * Also make sure the error code is SOCKET_ERROR_UNHANDLED because we
 714                  * only want to handle unhandled packages here.
 715                  */
 716                 /* NOISY-DEBUG: */ $this->debugOutput('NETWORK-PACKAGE: errorCode=' . $decodedData[BaseRawDataHandler::PACKAGE_ERROR_CODE]);
 717                 assert($decodedData[BaseRawDataHandler::PACKAGE_ERROR_CODE] == BaseRawDataHandler::SOCKET_ERROR_UNHANDLED);
 718
 719                 // Remove the last chunk SEPARATOR (because it is being added and we don't need it)
 720                 if (substr($decodedData[BaseRawDataHandler::PACKAGE_DECODED_DATA], -1, 1) == PackageFragmenter::CHUNK_SEPARATOR) {
 721                         // It is there and should be removed
 722                         $decodedData[BaseRawDataHandler::PACKAGE_DECODED_DATA] = substr($decodedData[BaseRawDataHandler::PACKAGE_DECODED_DATA], 0, -1);
 723                 } // END - if
 724
 725                 // This package is "handled" and can be pushed on the next stack
 726                 $this->getStackerInstance()->pushNamed(self::STACKER_NAME_DECODED_HANDLED, $decodedData);
 727         }
 728
 729         /**
 730          * Adds raw decoded data from the given handler instance to this receiver
 731          *
 732          * @param       $handlerInstance        An instance of a Networkable class
 733          * @return      void
 734          */
 735         public function addDecodedDataToIncomingStack (Networkable $handlerInstance) {
 736                 /*
 737                  * Get the decoded data from the handler, this is an array with
 738                  * 'decoded_data' and 'error_code' as elements.
 739                  */
 740                 $decodedData = $handlerInstance->getNextDecodedData();
 741
 742                 // Very noisy debug message:
 743                 //* NOISY-DEBUG: */ $this->debugOutput('PACKAGE: decodedData[' . gettype($decodedData) . ']=' . print_r($decodedData, true));
 744
 745                 // And push it on our stack
 746                 $this->getStackerInstance()->pushNamed(self::STACKER_NAME_DECODED_INCOMING, $decodedData);
 747         }
 748
 749         /**
 750          * Checks whether incoming decoded data is handled.
 751          *
 752          * @return      $isHandled      Whether incoming decoded data is handled
 753          */
 754         public function isIncomingDecodedDataHandled () {
 755                 // Determine if the stack is not empty
 756                 $isHandled = (!$this->getStackerInstance()->isStackEmpty(self::STACKER_NAME_DECODED_HANDLED));
 757
 758                 // Return it
 759                 return $isHandled;
 760         }
 761
 762         /**
 763          * Checks whether the assembler has pending data left
 764          *
 765          * @return      $isHandled      Whether the assembler has pending data left
 766          */
 767         public function ifAssemblerHasPendingDataLeft () {
 768                 // Determine if the stack is not empty
 769                 $isHandled = (!$this->getAssemblerInstance()->isPendingDataEmpty());
 770
 771                 // Return it
 772                 return $isHandled;
 773         }
 774
 775         /**
 776          * Handles the attached assemler's pending data queue to be finally
 777          * assembled to the raw package data back.
 778          *
 779          * @return      void
 780          */
 781         public function handleAssemblerPendingData () {
 782                 // Handle it
 783                 $this->getAssemblerInstance()->handlePendingData();
 784         }
 785
 786         /**
 787          * Assembles incoming decoded data so it will become an abstract network
 788          * package again. The assembler does later do it's job by an other task,
 789          * not this one to keep best speed possible.
 790          *
 791          * @return      void
 792          */
 793         public function assembleDecodedDataToPackage () {
 794                 // Make sure the raw decoded package data is handled
 795                 assert($this->isIncomingDecodedDataHandled());
 796
 797                 // Get current package content (an array with two elements; see handleIncomingDecodedData() for details)
 798                 $packageContent = $this->getStackerInstance()->getNamed(self::STACKER_NAME_DECODED_HANDLED);
 799
 800                 // Start assembling the raw package data array by chunking it
 801                 $this->getAssemblerInstance()->chunkPackageContent($packageContent);
 802
 803                 // Remove the package from 'handled_decoded' stack ...
 804                 $this->getStackerInstance()->popNamed(self::STACKER_NAME_DECODED_HANDLED);
 805
 806                 // ... and push it on the 'chunked' stacker
 807                 $this->getStackerInstance()->pushNamed(self::STACKER_NAME_DECODED_CHUNKED, $packageContent);
 808         }
 809
 810         /**
 811          * Checks whether a new package has arrived
 812          *
 813          * @return      $hasArrived             Whether a new package has arrived for processing
 814          */
 815         public function isNewPackageArrived () {
 816                 // @TODO Add some content here
 817         }
 818
 819         /**
 820          * Accepts the visitor to process the visit "request"
 821          *
 822          * @param       $visitorInstance        An instance of a Visitor class
 823          * @return      void
 824          */
 825         public function accept (Visitor $visitorInstance) {
 826                 // Debug message
 827                 //* NOISY-DEBUG: */ $this->debugOutput('PACKAGE: ' . $visitorInstance->__toString() . ' has visited - START');
 828
 829                 // Visit the package
 830                 $visitorInstance->visitNetworkPackage($this);
 831
 832                 // Debug message
 833                 //* NOISY-DEBUG: */ $this->debugOutput('PACKAGE: ' . $visitorInstance->__toString() . ' has visited - FINISHED');
 834         }
 835
 836         /**
 837          * Clears all stacker
 838          *
 839          * @return      void
 840          */
 841         public function clearAllStacker () {
 842                 // Call the init method to force re-initialization
 843                 $this->initStackers(true);
 844
 845                 // Debug message
 846                 /* DEBUG: */ $this->debugOutput('PACKAGE: All stacker have been re-initialized.');
 847         }
 848
 849         /**
 850          * Removes the first failed outoging package from the stack to continue
 851          * with next one (it will never work until the issue is fixed by you).
 852          *
 853          * @return      void
 854          * @throws      UnexpectedPackageStatusException        If the package status is not 'failed'
 855          * @todo        This may be enchanced for outgoing packages?
 856          */
 857         public function removeFirstFailedPackage () {
 858                 // Get the package again
 859                 $packageData = $this->getStackerInstance()->getNamed(self::STACKER_NAME_DECLARED);
 860
 861                 // Is the package status 'failed'?
 862                 if ($packageData[self::PACKAGE_DATA_STATUS] != self::PACKAGE_STATUS_FAILED) {
 863                         // Not failed!
 864                         throw new UnexpectedPackageStatusException(array($this, $packageData, self::PACKAGE_STATUS_FAILED), BaseListener::EXCEPTION_UNEXPECTED_PACKAGE_STATUS);
 865                 } // END - if
 866
 867                 // Remove this entry
 868                 $this->getStackerInstance()->popNamed(self::STACKER_NAME_DECLARED);
 869         }
 870
 871         /**
 872          * "Decode" the package content into the same array when it was sent.
 873          *
 874          * @param       $rawPackageContent      The raw package content to be "decoded"
 875          * @return      $decodedData            An array with 'sender', 'recipient', 'content' and 'status' elements
 876          */
 877         public function decodeRawContent ($rawPackageContent) {
 878                 // Use the separator '#' to "decode" it
 879                 $decodedArray = explode(self::PACKAGE_DATA_SEPARATOR, $rawPackageContent);
 880
 881                 // Assert on count (should be always 3)
 882                 assert(count($decodedArray) == self::DECODED_DATA_ARRAY_SIZE);
 883
 884                 // Create 'decodedData' array with all assoziative array elements
 885                 $decodedData = array(
 886                         self::PACKAGE_DATA_SENDER    => $decodedArray[self::INDEX_PACKAGE_SENDER],
 887                         self::PACKAGE_DATA_RECIPIENT => $decodedArray[self::INDEX_PACKAGE_RECIPIENT],
 888                         self::PACKAGE_DATA_CONTENT   => $decodedArray[self::INDEX_PACKAGE_CONTENT],
 889                         self::PACKAGE_DATA_STATUS    => self::PACKAGE_STATUS_DECODED,
 890                         self::PACKAGE_DATA_SIGNATURE => $this->generatePackageSignature($decodedArray[self::INDEX_PACKAGE_CONTENT], $decodedArray[self::INDEX_PACKAGE_SENDER])
 891                 );
 892
 893                 // And return it
 894                 return $decodedData;
 895         }
 896 }
 897
 898 // [EOF]
 899 ?>