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 - 2012 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          * Size of an array created by invoking
  56          * explode(NetworkPackage::PACKAGE_MASK_SEPARATOR, $content).
  57          */
  58         const PACKAGE_CONTENT_ARRAY_SIZE = 4;
  59
  60         /**
  61          * Separator for checksum
  62          */
  63         const PACKAGE_CHECKSUM_SEPARATOR = '_';
  64
  65         /**
  66          * Array indexes for above mask, start with zero
  67          */
  68         const INDEX_COMPRESSOR_EXTENSION = 0;
  69         const INDEX_PACKAGE_DATA         = 1;
  70         const INDEX_TAGS                 = 2;
  71         const INDEX_CHECKSUM             = 3;
  72
  73         /**
  74          * Array indexes for raw package array
  75          */
  76         const INDEX_PACKAGE_SENDER    = 0;
  77         const INDEX_PACKAGE_RECIPIENT = 1;
  78         const INDEX_PACKAGE_CONTENT   = 2;
  79         const INDEX_PACKAGE_STATUS    = 3;
  80         const INDEX_PACKAGE_SIGNATURE = 4;
  81
  82         /**
  83          * Size of the decoded data array ('status' is not included)
  84          */
  85         const DECODED_DATA_ARRAY_SIZE = 4;
  86
  87         /**
  88          * Named array elements for decoded package content
  89          */
  90         const PACKAGE_CONTENT_EXTENSION = 'compressor';
  91         const PACKAGE_CONTENT_MESSAGE   = 'message';
  92         const PACKAGE_CONTENT_TAGS      = 'tags';
  93         const PACKAGE_CONTENT_CHECKSUM  = 'checksum';
  94
  95         /**
  96          * Named array elements for package data
  97          */
  98         const PACKAGE_DATA_SENDER    = 'sender';
  99         const PACKAGE_DATA_RECIPIENT = 'recipient';
 100         const PACKAGE_DATA_PROTOCOL  = 'protocol';
 101         const PACKAGE_DATA_CONTENT   = 'content';
 102         const PACKAGE_DATA_STATUS    = 'status';
 103         const PACKAGE_DATA_SIGNATURE = 'signature';
 104
 105         /**
 106          * All package status
 107          */
 108         const PACKAGE_STATUS_NEW     = 'new';
 109         const PACKAGE_STATUS_FAILED  = 'failed';
 110         const PACKAGE_STATUS_DECODED = 'decoded';
 111
 112         /**
 113          * Constants for message data array
 114          */
 115         const MESSAGE_ARRAY_DATA = 'message_data';
 116         const MESSAGE_ARRAY_TYPE = 'message_type';
 117
 118         /**
 119          * Tags separator
 120          */
 121         const PACKAGE_TAGS_SEPARATOR = ';';
 122
 123         /**
 124          * Raw package data separator
 125          */
 126         const PACKAGE_DATA_SEPARATOR = '#';
 127
 128         /**
 129          * Network target (alias): 'upper hubs'
 130          */
 131         const NETWORK_TARGET_UPPER_HUBS = 'upper';
 132
 133         /**
 134          * Network target (alias): 'self'
 135          */
 136         const NETWORK_TARGET_SELF = 'self';
 137
 138         /**
 139          * Network target (alias): 'other'
 140          */
 141         const NETWORK_TARGET_OTHER = 'other';
 142
 143         /**
 144          * TCP package size in bytes
 145          */
 146         const TCP_PACKAGE_SIZE = 512;
 147
 148         /**************************************************************************
 149          *                    Stacker for out-going packages                      *
 150          **************************************************************************/
 151
 152         /**
 153          * Stacker name for "undeclared" packages
 154          */
 155         const STACKER_NAME_UNDECLARED = 'package_undeclared';
 156
 157         /**
 158          * Stacker name for "declared" packages (which are ready to send out)
 159          */
 160         const STACKER_NAME_DECLARED = 'package_declared';
 161
 162         /**
 163          * Stacker name for "out-going" packages
 164          */
 165         const STACKER_NAME_OUTGOING = 'package_outgoing';
 166
 167         /**************************************************************************
 168          *                     Stacker for incoming packages                      *
 169          **************************************************************************/
 170
 171         /**
 172          * Stacker name for "incoming" decoded raw data
 173          */
 174         const STACKER_NAME_DECODED_INCOMING = 'package_decoded_data';
 175
 176         /**
 177          * Stacker name for handled decoded raw data
 178          */
 179         const STACKER_NAME_DECODED_HANDLED = 'package_handled_decoded';
 180
 181         /**
 182          * Stacker name for "chunked" decoded raw data
 183          */
 184         const STACKER_NAME_DECODED_CHUNKED = 'package_chunked_decoded';
 185
 186         /**************************************************************************
 187          *                     Stacker for incoming messages                      *
 188          **************************************************************************/
 189
 190         /**
 191          * Stacker name for new messages
 192          */
 193         const STACKER_NAME_NEW_MESSAGE = 'package_new_message';
 194
 195         /**
 196          * Stacker name for processed messages
 197          */
 198         const STACKER_NAME_PROCESSED_MESSAGE = 'package_processed_message';
 199
 200         /**************************************************************************
 201          *                   Stacker for other/internal purposes                  *
 202          **************************************************************************/
 203
 204         /**
 205          * Stacker name for "back-buffered" packages
 206          */
 207         const STACKER_NAME_BACK_BUFFER = 'package_backbuffer';
 208
 209         /**
 210          * Protected constructor
 211          *
 212          * @return      void
 213          */
 214         protected function __construct () {
 215                 // Call parent constructor
 216                 parent::__construct(__CLASS__);
 217         }
 218
 219         /**
 220          * Creates an instance of this class
 221          *
 222          * @param       $compressorInstance             A Compressor instance for compressing the content
 223          * @return      $packageInstance                An instance of a Deliverable class
 224          */
 225         public static final function createNetworkPackage (Compressor $compressorInstance) {
 226                 // Get new instance
 227                 $packageInstance = new NetworkPackage();
 228
 229                 // Now set the compressor instance
 230                 $packageInstance->setCompressorInstance($compressorInstance);
 231
 232                 /*
 233                  * We need to initialize a stack here for our packages even for those
 234                  * which have no recipient address and stamp... ;-) This stacker will
 235                  * also be used for incoming raw data to handle it.
 236                  */
 237                 $stackerInstance = ObjectFactory::createObjectByConfiguredName('network_package_stacker_class');
 238
 239                 // At last, set it in this class
 240                 $packageInstance->setStackerInstance($stackerInstance);
 241
 242                 // Init all stacker
 243                 $packageInstance->initStackers();
 244
 245                 // Get a visitor instance for speeding up things
 246                 $visitorInstance = ObjectFactory::createObjectByConfiguredName('node_raw_data_monitor_visitor_class', array($packageInstance));
 247
 248                 // Set it in this package
 249                 $packageInstance->setVisitorInstance($visitorInstance);
 250
 251                 // Get crypto instance and set it in this package
 252                 $cryptoInstance = ObjectFactory::createObjectByConfiguredName('crypto_class');
 253                 $packageInstance->setCryptoInstance($cryptoInstance);
 254
 255                 // Get a singleton package assembler instance from factory and set it here
 256                 $assemblerInstance = PackageAssemblerFactory::createAssemblerInstance($packageInstance);
 257                 $packageInstance->setAssemblerInstance($assemblerInstance);
 258
 259                 // Return the prepared instance
 260                 return $packageInstance;
 261         }
 262
 263         /**
 264          * Initialize all stackers
 265          *
 266          * @param       $forceReInit    Whether to force reinitialization of all stacks
 267          * @return      void
 268          */
 269         protected function initStackers ($forceReInit = false) {
 270                 // Initialize all
 271                 foreach (
 272                         array(
 273                                 self::STACKER_NAME_UNDECLARED,
 274                                 self::STACKER_NAME_DECLARED,
 275                                 self::STACKER_NAME_OUTGOING,
 276                                 self::STACKER_NAME_DECODED_INCOMING,
 277                                 self::STACKER_NAME_DECODED_HANDLED,
 278                                 self::STACKER_NAME_DECODED_CHUNKED,
 279                                 self::STACKER_NAME_NEW_MESSAGE,
 280                                 self::STACKER_NAME_PROCESSED_MESSAGE,
 281                                 self::STACKER_NAME_BACK_BUFFER
 282                         ) as $stackerName) {
 283                                 // Init this stacker
 284                                 $this->getStackerInstance()->initStacker($stackerName, $forceReInit);
 285                 } // END - foreach
 286         }
 287
 288         /**
 289          * "Getter" for hash from given content
 290          *
 291          * @param       $content        Raw package content
 292          * @return      $hash           Hash for given package content
 293          */
 294         private function getHashFromContent ($content) {
 295                 // Debug message
 296                 //* NOISY-DEBUG: */ $this->debugOutput('NETWORK-PACKAGE: content[md5]=' . md5($content) . ',sender=' . $this->getSessionId() . ',compressor=' . $this->getCompressorInstance()->getCompressorExtension());
 297
 298                 // Create the hash
 299                 // @TODO crc32() is very weak, but it needs to be fast
 300                 $hash = crc32(
 301                         $content .
 302                         self::PACKAGE_CHECKSUM_SEPARATOR .
 303                         $this->getSessionId() .
 304                         self::PACKAGE_CHECKSUM_SEPARATOR .
 305                         $this->getCompressorInstance()->getCompressorExtension()
 306                 );
 307
 308                 // And return it
 309                 return $hash;
 310         }
 311
 312         /**
 313          * Checks whether the checksum (sometimes called "hash") is the same
 314          *
 315          * @param       $decodedContent         Package raw content
 316          * @param       $decodedData            Whole raw package data array
 317          * @return      $isChecksumValid        Whether the checksum is the same
 318          */
 319         private function isChecksumValid (array $decodedContent, array $decodedData) {
 320                 // Get checksum
 321                 $checksum = $this->getHashFromContentSessionId($decodedContent, $decodedData[self::PACKAGE_DATA_SENDER]);
 322
 323                 // Is it the same?
 324                 $isChecksumValid = ($checksum == $decodedContent[self::PACKAGE_CONTENT_CHECKSUM]);
 325
 326                 // Return it
 327                 return $isChecksumValid;
 328         }
 329
 330         /**
 331          * Change the package with given status in given stack
 332          *
 333          * @param       $packageData    Raw package data in an array
 334          * @param       $stackerName    Name of the stacker
 335          * @param       $newStatus              New status to set
 336          * @return      void
 337          */
 338         private function changePackageStatus (array $packageData, $stackerName, $newStatus) {
 339                 // Skip this for empty stacks
 340                 if ($this->getStackerInstance()->isStackEmpty($stackerName)) {
 341                         // This avoids an exception after all packages has failed
 342                         return;
 343                 } // END - if
 344
 345                 // Pop the entry (it should be it)
 346                 $nextData = $this->getStackerInstance()->popNamed($stackerName);
 347
 348                 // Compare both signatures
 349                 assert($nextData[self::PACKAGE_DATA_SIGNATURE] == $packageData[self::PACKAGE_DATA_SIGNATURE]);
 350
 351                 // Temporary set the new status
 352                 $packageData[self::PACKAGE_DATA_STATUS] = $newStatus;
 353
 354                 // And push it again
 355                 $this->getStackerInstance()->pushNamed($stackerName, $packageData);
 356         }
 357
 358         /**
 359          * "Getter" for hash from given content and sender's session id
 360          *
 361          * @param       $decodedContent         Decoded package content
 362          * @param       $sessionId                      Session id of the sender
 363          * @return      $hash                           Hash for given package content
 364          */
 365         public function getHashFromContentSessionId (array $decodedContent, $sessionId) {
 366                 // Debug message
 367                 //* NOISY-DEBUG: */ $this->debugOutput('NETWORK-PACKAGE: content[md5]=' . md5($decodedContent[self::PACKAGE_CONTENT_MESSAGE]) . ',sender=' . $sessionId . ',compressor=' . $decodedContent[self::PACKAGE_CONTENT_EXTENSION]);
 368
 369                 // Create the hash
 370                 // @TODO crc32() is very weak, but it needs to be fast
 371                 $hash = crc32(
 372                         $decodedContent[self::PACKAGE_CONTENT_MESSAGE] .
 373                         self::PACKAGE_CHECKSUM_SEPARATOR .
 374                         $sessionId .
 375                         self::PACKAGE_CHECKSUM_SEPARATOR .
 376                         $decodedContent[self::PACKAGE_CONTENT_EXTENSION]
 377                 );
 378
 379                 // And return it
 380                 return $hash;
 381         }
 382
 383         ///////////////////////////////////////////////////////////////////////////
 384         //                   Delivering packages / raw data
 385         ///////////////////////////////////////////////////////////////////////////
 386
 387         /**
 388          * Delivers the given raw package data.
 389          *
 390          * @param       $packageData    Raw package data in an array
 391          * @return      void
 392          */
 393         private function declareRawPackageData (array $packageData) {
 394                 /*
 395                  * We need to disover every recipient, just in case we have a
 396                  * multi-recipient entry like 'upper' is. 'all' may be a not so good
 397                  * target because it causes an overload on the network and may be
 398                  * abused for attacking the network with large packages.
 399                  */
 400                 $discoveryInstance = PackageDiscoveryFactory::createPackageDiscoveryInstance();
 401
 402                 // Discover all recipients, this may throw an exception
 403                 $discoveryInstance->discoverRecipients($packageData);
 404
 405                 // Now get an iterator
 406                 $iteratorInstance = $discoveryInstance->getIterator();
 407
 408                 // Rewind back to the beginning
 409                 $iteratorInstance->rewind();
 410
 411                 // ... and begin iteration
 412                 while ($iteratorInstance->valid()) {
 413                         // Get current entry
 414                         $currentRecipient = $iteratorInstance->current();
 415
 416                         // Set the recipient
 417                         $packageData[self::PACKAGE_DATA_RECIPIENT] = $currentRecipient;
 418
 419                         // And enqueue it to the writer class
 420                         $this->getStackerInstance()->pushNamed(self::STACKER_NAME_DECLARED, $packageData);
 421
 422                         // Debug message
 423                         $this->debugOutput('PACKAGE: Package declared for recipient ' . $currentRecipient);
 424
 425                         // Skip to next entry
 426                         $iteratorInstance->next();
 427                 } // END - while
 428
 429                 /*
 430                  * The recipient list can be cleaned up here because the package which
 431                  * shall be delivered has already been added for all entries from the
 432                  * list.
 433                  */
 434                 $discoveryInstance->clearRecipients();
 435         }
 436
 437         /**
 438          * Delivers raw package data. In short, this will discover the raw socket
 439          * resource through a discovery class (which will analyse the receipient of
 440          * the package), register the socket with the connection (handler/helper?)
 441          * instance and finally push the raw data on our outgoing queue.
 442          *
 443          * @param       $packageData    Raw package data in an array
 444          * @return      void
 445          */
 446         private function deliverRawPackageData (array $packageData) {
 447                 /*
 448                  * This package may become big, depending on the shared object size or
 449                  * delivered message size which shouldn't be so long (to save
 450                  * bandwidth). Because of the nature of the used protocol (TCP) we need
 451                  * to split it up into smaller pieces to fit it into a TCP frame.
 452                  *
 453                  * So first we need (again) a discovery class but now a protocol
 454                  * discovery to choose the right socket resource. The discovery class
 455                  * should take a look at the raw package data itself and then decide
 456                  * which (configurable!) protocol should be used for that type of
 457                  * package.
 458                  */
 459                 $discoveryInstance = SocketDiscoveryFactory::createSocketDiscoveryInstance();
 460
 461                 // Now discover the right protocol
 462                 $socketResource = $discoveryInstance->discoverSocket($packageData);
 463
 464                 // Debug message
 465                 //* NOISY-DEBUG: */ $this->debugOutput('PACKAGE: Reached line ' . __LINE__ . ' after discoverSocket() has been called.');
 466
 467                 // We have to put this socket in our registry, so get an instance
 468                 $registryInstance = SocketRegistry::createSocketRegistry();
 469
 470                 // Get the listener from registry
 471                 $helperInstance = Registry::getRegistry()->getInstance('connection');
 472
 473                 // Debug message
 474                 //* NOISY-DEBUG: */ $this->debugOutput('PACKAGE: stateInstance=' . $helperInstance->getStateInstance());
 475                 //* NOISY-DEBUG: */ $this->debugOutput('PACKAGE: Reached line ' . __LINE__ . ' before isSocketRegistered() has been called.');
 476
 477                 // Is it not there?
 478                 if ((is_resource($socketResource)) && (!$registryInstance->isSocketRegistered($helperInstance, $socketResource))) {
 479                         // Debug message
 480                         $this->debugOutput('PACKAGE: Registering socket ' . $socketResource . ' ...');
 481
 482                         // Then register it
 483                         $registryInstance->registerSocket($helperInstance, $socketResource, $packageData);
 484                 } elseif (!$helperInstance->getStateInstance()->isPeerStateConnected()) {
 485                         // Is not connected, then we cannot send
 486                         $this->debugOutput('PACKAGE: Unexpected peer state ' . $helperInstance->getStateInstance()->__toString() . ' detected.');
 487
 488                         // Shutdown the socket
 489                         $this->shutdownSocket($socketResource);
 490                 }
 491
 492                 // Debug message
 493                 //* NOISY-DEBUG: */ $this->debugOutput('PACKAGE: Reached line ' . __LINE__ . ' after isSocketRegistered() has been called.');
 494
 495                 // Make sure the connection is up
 496                 $helperInstance->getStateInstance()->validatePeerStateConnected();
 497
 498                 // Debug message
 499                 //* NOISY-DEBUG: */ $this->debugOutput('PACKAGE: Reached line ' . __LINE__ . ' after validatePeerStateConnected() has been called.');
 500
 501                 // Enqueue it again on the out-going queue, the connection is up and working at this point
 502                 $this->getStackerInstance()->pushNamed(self::STACKER_NAME_OUTGOING, $packageData);
 503
 504                 // Debug message
 505                 //* NOISY-DEBUG: */ $this->debugOutput('PACKAGE: Reached line ' . __LINE__ . ' after pushNamed() has been called.');
 506         }
 507
 508         /**
 509          * Sends waiting packages
 510          *
 511          * @param       $packageData    Raw package data
 512          * @return      void
 513          */
 514         private function sendOutgoingRawPackageData (array $packageData) {
 515                 // Init sent bytes
 516                 $sentBytes = 0;
 517
 518                 // Get the right connection instance
 519                 $helperInstance = SocketRegistry::createSocketRegistry()->getHandlerInstanceFromPackageData($packageData);
 520
 521                 // Is this connection still alive?
 522                 if ($helperInstance->isShuttedDown()) {
 523                         // This connection is shutting down
 524                         // @TODO We may want to do somthing more here?
 525                         return;
 526                 } // END - if
 527
 528                 // Sent out package data
 529                 $sentBytes = $helperInstance->sendRawPackageData($packageData);
 530
 531                 // Remember unsent raw bytes in back-buffer, if any
 532                 $this->storeUnsentBytesInBackBuffer($packageData, $sentBytes);
 533         }
 534
 535         /**
 536          * Generates a signature for given raw package content and sender id
 537          *
 538          * @param       $content        Raw package data
 539          * @param       $senderId       Sender id to generate a signature for
 540          * @return      $signature      Signature as BASE64-encoded string
 541          */
 542         private function generatePackageSignature ($content, $senderId) {
 543                 // ash content and sender id together, use md5() as last algo
 544                 $hash = md5($this->getCryptoInstance()->hashString($senderId . $content, $this->getNodeId(), false));
 545
 546                 // Encrypt the content again with the hash as a key
 547                 $encryptedContent = $this->getCryptoInstance()->encryptString($content, $hash);
 548
 549                 // Encode it with BASE64
 550                 $signature = base64_encode($encryptedContent);
 551
 552                 // Return it
 553                 return $signature;
 554         }
 555
 556         /**
 557          * Checks whether the signature of given package data is 'valid', here that
 558          * means it is the same or not.
 559          *
 560          * @param       $decodedArray           An array with 'decoded' (explode() was mostly called) data
 561          * @return      $isSignatureValid       Whether the signature is valid
 562          * @todo        Unfinished area, signatures are currently NOT fully supported
 563          */
 564         private function isPackageSignatureValid (array $decodedArray) {
 565                 // Generate the signature of comparing it
 566                 $signature = $this->generatePackageSignature($decodedArray[self::INDEX_PACKAGE_CONTENT], $decodedArray[self::INDEX_PACKAGE_SENDER]);
 567
 568                 // Is it the same?
 569                 //$isSignatureValid =
 570                 die(__METHOD__.': signature='.$signature.chr(10).',decodedArray='.print_r($decodedArray,true));
 571         }
 572
 573         /**
 574          * "Enqueues" raw content into this delivery class by reading the raw content
 575          * from given helper's template instance and pushing it on the 'undeclared'
 576          * stack.
 577          *
 578          * @param       $helperInstance         An instance of a HelpableHub class
 579          * @param       $protocol                       Name of used protocol (TCP/UDP)
 580          * @return      void
 581          */
 582         public function enqueueRawDataFromTemplate (HelpableHub $helperInstance, $protocolName) {
 583                 // Get the raw content ...
 584                 $content = $helperInstance->getTemplateInstance()->getRawTemplateData();
 585
 586                 // ... and compress it
 587                 $content = $this->getCompressorInstance()->compressStream($content);
 588
 589                 // Add magic in front of it and hash behind it, including BASE64 encoding
 590                 $content = sprintf(self::PACKAGE_MASK,
 591                         // 1.) Compressor's extension
 592                         $this->getCompressorInstance()->getCompressorExtension(),
 593                         // - separator
 594                         self::PACKAGE_MASK_SEPARATOR,
 595                         // 2.) Raw package content, encoded with BASE64
 596                         base64_encode($content),
 597                         // - separator
 598                         self::PACKAGE_MASK_SEPARATOR,
 599                         // 3.) Tags
 600                         implode(self::PACKAGE_TAGS_SEPARATOR, $helperInstance->getPackageTags()),
 601                         // - separator
 602                         self::PACKAGE_MASK_SEPARATOR,
 603                         // 4.) Checksum
 604                         $this->getHashFromContent($content)
 605                 );
 606
 607                 // Now prepare the temporary array and push it on the 'undeclared' stack
 608                 $this->getStackerInstance()->pushNamed(self::STACKER_NAME_UNDECLARED, array(
 609                         self::PACKAGE_DATA_SENDER    => $this->getSessionId(),
 610                         self::PACKAGE_DATA_RECIPIENT => $helperInstance->getRecipientType(),
 611                         self::PACKAGE_DATA_PROTOCOL  => $protocolName,
 612                         self::PACKAGE_DATA_CONTENT   => $content,
 613                         self::PACKAGE_DATA_STATUS    => self::PACKAGE_STATUS_NEW,
 614                         self::PACKAGE_DATA_SIGNATURE => $this->generatePackageSignature($content, $this->getSessionId())
 615                 ));
 616         }
 617
 618         /**
 619          * Checks whether a package has been enqueued for delivery.
 620          *
 621          * @return      $isEnqueued             Whether a package is enqueued
 622          */
 623         public function isPackageEnqueued () {
 624                 // Check whether the stacker is not empty
 625                 $isEnqueued = (($this->getStackerInstance()->isStackInitialized(self::STACKER_NAME_UNDECLARED)) && (!$this->getStackerInstance()->isStackEmpty(self::STACKER_NAME_UNDECLARED)));
 626
 627                 // Return the result
 628                 return $isEnqueued;
 629         }
 630
 631         /**
 632          * Checks whether a package has been declared
 633          *
 634          * @return      $isDeclared             Whether a package is declared
 635          */
 636         public function isPackageDeclared () {
 637                 // Check whether the stacker is not empty
 638                 $isDeclared = (($this->getStackerInstance()->isStackInitialized(self::STACKER_NAME_DECLARED)) && (!$this->getStackerInstance()->isStackEmpty(self::STACKER_NAME_DECLARED)));
 639
 640                 // Return the result
 641                 return $isDeclared;
 642         }
 643
 644         /**
 645          * Checks whether a package should be sent out
 646          *
 647          * @return      $isWaitingDelivery      Whether a package is waiting for delivery
 648          */
 649         public function isPackageWaitingForDelivery () {
 650                 // Check whether the stacker is not empty
 651                 $isWaitingDelivery = (($this->getStackerInstance()->isStackInitialized(self::STACKER_NAME_OUTGOING)) && (!$this->getStackerInstance()->isStackEmpty(self::STACKER_NAME_OUTGOING)));
 652
 653                 // Return the result
 654                 return $isWaitingDelivery;
 655         }
 656
 657         /**
 658          * Delivers an enqueued package to the stated destination. If a non-session
 659          * id is provided, recipient resolver is being asked (and instanced once).
 660          * This allows that a single package is being delivered to multiple targets
 661          * without enqueueing it for every target. If no target is provided or it
 662          * can't be determined a NoTargetException is being thrown.
 663          *
 664          * @return      void
 665          * @throws      NoTargetException       If no target can't be determined
 666          */
 667         public function declareEnqueuedPackage () {
 668                 // Make sure this method isn't working if there is no package enqueued
 669                 if (!$this->isPackageEnqueued()) {
 670                         // This is not fatal but should be avoided
 671                         // @TODO Add some logging here
 672                         return;
 673                 } // END - if
 674
 675                 /*
 676                  * Now there are for sure packages to deliver, so start with the first
 677                  * one.
 678                  */
 679                 $packageData = $this->getStackerInstance()->getNamed(self::STACKER_NAME_UNDECLARED);
 680
 681                 // Declare the raw package data for delivery
 682                 $this->declareRawPackageData($packageData);
 683
 684                 // And remove it finally
 685                 $this->getStackerInstance()->popNamed(self::STACKER_NAME_UNDECLARED);
 686         }
 687
 688         /**
 689          * Delivers the next declared package. Only one package per time will be sent
 690          * because this may take time and slows down the whole delivery
 691          * infrastructure.
 692          *
 693          * @return      void
 694          */
 695         public function deliverDeclaredPackage () {
 696                 // Sanity check if we have packages declared
 697                 if (!$this->isPackageDeclared()) {
 698                         // This is not fatal but should be avoided
 699                         $this->debugOutput('PACKAGE: No package has been declared, but ' . __METHOD__ . ' has been called!');
 700                         return;
 701                 } // END - if
 702
 703                 // Get the package
 704                 $packageData = $this->getStackerInstance()->getNamed(self::STACKER_NAME_DECLARED);
 705
 706                 try {
 707                         // And try to send it
 708                         $this->deliverRawPackageData($packageData);
 709
 710                         // And remove it finally
 711                         $this->getStackerInstance()->popNamed(self::STACKER_NAME_DECLARED);
 712                 } catch (InvalidStateException $e) {
 713                         // The state is not excepected (shall be 'connected')
 714                         $this->debugOutput('PACKAGE: Caught ' . $e->__toString() . ',message=' . $e->getMessage());
 715
 716                         // Mark the package with status failed
 717                         $this->changePackageStatus($packageData, self::STACKER_NAME_DECLARED, self::PACKAGE_STATUS_FAILED);
 718                 }
 719         }
 720
 721         /**
 722          * Sends waiting packages out for delivery
 723          *
 724          * @return      void
 725          */
 726         public function sendWaitingPackage () {
 727                 // Send any waiting bytes in the back-buffer before sending a new package
 728                 $this->sendBackBufferBytes();
 729
 730                 // Sanity check if we have packages waiting for delivery
 731                 if (!$this->isPackageWaitingForDelivery()) {
 732                         // This is not fatal but should be avoided
 733                         $this->debugOutput('PACKAGE: No package is waiting for delivery, but ' . __METHOD__ . ' was called.');
 734                         return;
 735                 } // END - if
 736
 737                 // Get the package
 738                 $packageData = $this->getStackerInstance()->getNamed(self::STACKER_NAME_OUTGOING);
 739
 740                 try {
 741                         // Now try to send it
 742                         $this->sendOutgoingRawPackageData($packageData);
 743
 744                         // And remove it finally
 745                         $this->getStackerInstance()->popNamed(self::STACKER_NAME_OUTGOING);
 746                 } catch (InvalidSocketException $e) {
 747                         // Output exception message
 748                         $this->debugOutput('PACKAGE: Package was not delivered: ' . $e->getMessage());
 749
 750                         // Mark package as failed
 751                         $this->changePackageStatus($packageData, self::STACKER_NAME_OUTGOING, self::PACKAGE_STATUS_FAILED);
 752                 }
 753         }
 754
 755         ///////////////////////////////////////////////////////////////////////////
 756         //                   Receiving packages / raw data
 757         ///////////////////////////////////////////////////////////////////////////
 758
 759         /**
 760          * Checks whether decoded raw data is pending
 761          *
 762          * @return      $isPending      Whether decoded raw data is pending
 763          */
 764         private function isDecodedDataPending () {
 765                 // Just return whether the stack is not empty
 766                 $isPending = (!$this->getStackerInstance()->isStackEmpty(self::STACKER_NAME_DECODED_INCOMING));
 767
 768                 // Return the status
 769                 return $isPending;
 770         }
 771
 772         /**
 773          * Checks whether new raw package data has arrived at a socket
 774          *
 775          * @param       $poolInstance   An instance of a PoolableListener class
 776          * @return      $hasArrived             Whether new raw package data has arrived for processing
 777          */
 778         public function isNewRawDataPending (PoolableListener $poolInstance) {
 779                 // Visit the pool. This monitors the pool for incoming raw data.
 780                 $poolInstance->accept($this->getVisitorInstance());
 781
 782                 // Check for new data arrival
 783                 $hasArrived = $this->isDecodedDataPending();
 784
 785                 // Return the status
 786                 return $hasArrived;
 787         }
 788
 789         /**
 790          * Handles the incoming decoded raw data. This method does not "convert" the
 791          * decoded data back into a package array, it just "handles" it and pushs it
 792          * on the next stack.
 793          *
 794          * @return      void
 795          */
 796         public function handleIncomingDecodedData () {
 797                 /*
 798                  * This method should only be called if decoded raw data is pending,
 799                  * so check it again.
 800                  */
 801                 if (!$this->isDecodedDataPending()) {
 802                         // This is not fatal but should be avoided
 803                         // @TODO Add some logging here
 804                         return;
 805                 } // END - if
 806
 807                 // Very noisy debug message:
 808                 /* NOISY-DEBUG: */ $this->debugOutput('PACKAGE: Stacker size is ' . $this->getStackerInstance()->getStackCount(self::STACKER_NAME_DECODED_INCOMING) . ' entries.');
 809
 810                 // "Pop" the next entry (the same array again) from the stack
 811                 $decodedData = $this->getStackerInstance()->popNamed(self::STACKER_NAME_DECODED_INCOMING);
 812
 813                 // Make sure both array elements are there
 814                 assert(
 815                         (is_array($decodedData)) &&
 816                         (isset($decodedData[BaseRawDataHandler::PACKAGE_DECODED_DATA])) &&
 817                         (isset($decodedData[BaseRawDataHandler::PACKAGE_ERROR_CODE]))
 818                 );
 819
 820                 /*
 821                  * Also make sure the error code is SOCKET_ERROR_UNHANDLED because we
 822                  * only want to handle unhandled packages here.
 823                  */
 824                 /* NOISY-DEBUG: */ $this->debugOutput('NETWORK-PACKAGE: errorCode=' . $decodedData[BaseRawDataHandler::PACKAGE_ERROR_CODE]);
 825                 assert($decodedData[BaseRawDataHandler::PACKAGE_ERROR_CODE] == BaseRawDataHandler::SOCKET_ERROR_UNHANDLED);
 826
 827                 // Remove the last chunk SEPARATOR (because it is being added and we don't need it)
 828                 if (substr($decodedData[BaseRawDataHandler::PACKAGE_DECODED_DATA], -1, 1) == PackageFragmenter::CHUNK_SEPARATOR) {
 829                         // It is there and should be removed
 830                         $decodedData[BaseRawDataHandler::PACKAGE_DECODED_DATA] = substr($decodedData[BaseRawDataHandler::PACKAGE_DECODED_DATA], 0, -1);
 831                 } // END - if
 832
 833                 // This package is "handled" and can be pushed on the next stack
 834                 $this->getStackerInstance()->pushNamed(self::STACKER_NAME_DECODED_HANDLED, $decodedData);
 835         }
 836
 837         /**
 838          * Adds raw decoded data from the given handler instance to this receiver
 839          *
 840          * @param       $handlerInstance        An instance of a Networkable class
 841          * @return      void
 842          */
 843         public function addDecodedDataToIncomingStack (Networkable $handlerInstance) {
 844                 /*
 845                  * Get the decoded data from the handler, this is an array with
 846                  * 'decoded_data' and 'error_code' as elements.
 847                  */
 848                 $decodedData = $handlerInstance->getNextDecodedData();
 849
 850                 // Very noisy debug message:
 851                 //* NOISY-DEBUG: */ $this->debugOutput('PACKAGE: decodedData[' . gettype($decodedData) . ']=' . print_r($decodedData, true));
 852
 853                 // And push it on our stack
 854                 $this->getStackerInstance()->pushNamed(self::STACKER_NAME_DECODED_INCOMING, $decodedData);
 855         }
 856
 857         /**
 858          * Checks whether incoming decoded data is handled.
 859          *
 860          * @return      $isHandled      Whether incoming decoded data is handled
 861          */
 862         public function isIncomingDecodedDataHandled () {
 863                 // Determine if the stack is not empty
 864                 $isHandled = (!$this->getStackerInstance()->isStackEmpty(self::STACKER_NAME_DECODED_HANDLED));
 865
 866                 // Return it
 867                 return $isHandled;
 868         }
 869
 870         /**
 871          * Checks whether the assembler has pending data left
 872          *
 873          * @return      $isHandled      Whether the assembler has pending data left
 874          */
 875         public function ifAssemblerHasPendingDataLeft () {
 876                 // Determine if the stack is not empty
 877                 $isHandled = (!$this->getAssemblerInstance()->isPendingDataEmpty());
 878
 879                 // Return it
 880                 return $isHandled;
 881         }
 882
 883         /**
 884          * Handles the attached assemler's pending data queue to be finally
 885          * assembled to the raw package data back.
 886          *
 887          * @return      void
 888          */
 889         public function handleAssemblerPendingData () {
 890                 // Handle it
 891                 $this->getAssemblerInstance()->handlePendingData();
 892         }
 893
 894         /**
 895          * Assembles incoming decoded data so it will become an abstract network
 896          * package again. The assembler does later do it's job by an other task,
 897          * not this one to keep best speed possible.
 898          *
 899          * @return      void
 900          */
 901         public function assembleDecodedDataToPackage () {
 902                 // Make sure the raw decoded package data is handled
 903                 assert($this->isIncomingDecodedDataHandled());
 904
 905                 // Get current package content (an array with two elements; see handleIncomingDecodedData() for details)
 906                 $packageContent = $this->getStackerInstance()->getNamed(self::STACKER_NAME_DECODED_HANDLED);
 907
 908                 // Start assembling the raw package data array by chunking it
 909                 $this->getAssemblerInstance()->chunkPackageContent($packageContent);
 910
 911                 // Remove the package from 'handled_decoded' stack ...
 912                 $this->getStackerInstance()->popNamed(self::STACKER_NAME_DECODED_HANDLED);
 913
 914                 // ... and push it on the 'chunked' stacker
 915                 $this->getStackerInstance()->pushNamed(self::STACKER_NAME_DECODED_CHUNKED, $packageContent);
 916         }
 917
 918         /**
 919          * Accepts the visitor to process the visit "request"
 920          *
 921          * @param       $visitorInstance        An instance of a Visitor class
 922          * @return      void
 923          */
 924         public function accept (Visitor $visitorInstance) {
 925                 // Debug message
 926                 //* NOISY-DEBUG: */ $this->debugOutput('PACKAGE: ' . $visitorInstance->__toString() . ' has visited - START');
 927
 928                 // Visit the package
 929                 $visitorInstance->visitNetworkPackage($this);
 930
 931                 // Debug message
 932                 //* NOISY-DEBUG: */ $this->debugOutput('PACKAGE: ' . $visitorInstance->__toString() . ' has visited - FINISHED');
 933         }
 934
 935         /**
 936          * Clears all stacker
 937          *
 938          * @return      void
 939          */
 940         public function clearAllStacker () {
 941                 // Call the init method to force re-initialization
 942                 $this->initStackers(true);
 943
 944                 // Debug message
 945                 /* DEBUG: */ $this->debugOutput('PACKAGE: All stacker have been re-initialized.');
 946         }
 947
 948         /**
 949          * Removes the first failed outoging package from the stack to continue
 950          * with next one (it will never work until the issue is fixed by you).
 951          *
 952          * @return      void
 953          * @throws      UnexpectedPackageStatusException        If the package status is not 'failed'
 954          * @todo        This may be enchanced for outgoing packages?
 955          */
 956         public function removeFirstFailedPackage () {
 957                 // Get the package again
 958                 $packageData = $this->getStackerInstance()->getNamed(self::STACKER_NAME_DECLARED);
 959
 960                 // Is the package status 'failed'?
 961                 if ($packageData[self::PACKAGE_DATA_STATUS] != self::PACKAGE_STATUS_FAILED) {
 962                         // Not failed!
 963                         throw new UnexpectedPackageStatusException(array($this, $packageData, self::PACKAGE_STATUS_FAILED), BaseListener::EXCEPTION_UNEXPECTED_PACKAGE_STATUS);
 964                 } // END - if
 965
 966                 // Remove this entry
 967                 $this->getStackerInstance()->popNamed(self::STACKER_NAME_DECLARED);
 968         }
 969
 970         /**
 971          * "Decode" the package content into the same array when it was sent.
 972          *
 973          * @param       $rawPackageContent      The raw package content to be "decoded"
 974          * @return      $decodedData            An array with 'sender', 'recipient', 'content' and 'status' elements
 975          */
 976         public function decodeRawContent ($rawPackageContent) {
 977                 // Use the separator '#' to "decode" it
 978                 $decodedArray = explode(self::PACKAGE_DATA_SEPARATOR, $rawPackageContent);
 979
 980                 // Assert on count (should be always 3)
 981                 assert(count($decodedArray) == self::DECODED_DATA_ARRAY_SIZE);
 982
 983                 // Generate the signature of comparing it
 984                 /*
 985                  * @todo Unsupported feature of "signed" messages commented out
 986                 if (!$this->isPackageSignatureValid($decodedArray)) {
 987                         // Is not valid, so throw an exception here
 988                         die(__METHOD__ . ':INVALID SIG! UNDER CONSTRUCTION!' . chr(10));
 989                 } // END - if
 990                 */
 991
 992                 /*
 993                  * Create 'decodedData' array with all assoziative array elements,
 994                  * except signature.
 995                  */
 996                 $decodedData = array(
 997                         self::PACKAGE_DATA_SENDER    => $decodedArray[self::INDEX_PACKAGE_SENDER],
 998                         self::PACKAGE_DATA_RECIPIENT => $decodedArray[self::INDEX_PACKAGE_RECIPIENT],
 999                         self::PACKAGE_DATA_CONTENT   => $decodedArray[self::INDEX_PACKAGE_CONTENT],
1000                         self::PACKAGE_DATA_STATUS    => self::PACKAGE_STATUS_DECODED
1001                 );
1002
1003                 // And return it
1004                 return $decodedData;
1005         }
1006
1007         /**
1008          * Handles decoded data for this node by "decoding" the 'content' part of
1009          * it. Again this method uses explode() for the "decoding" process.
1010          *
1011          * @param       $decodedData    An array with decoded raw package data
1012          * @return      void
1013          * @throws      InvalidDataChecksumException    If the checksum doesn't match
1014          */
1015         public function handleDecodedData (array $decodedData) {
1016                 /*
1017                  * "Decode" the package's content by a simple explode() call, for
1018                  * details of the array elements, see comments for constant
1019                  * PACKAGE_MASK.
1020                  */
1021                 $decodedContent = explode(self::PACKAGE_MASK_SEPARATOR, $decodedData[self::PACKAGE_DATA_CONTENT]);
1022
1023                 // Assert on array count for a very basic validation
1024                 assert(count($decodedContent) == self::PACKAGE_CONTENT_ARRAY_SIZE);
1025
1026                 /*
1027                  * Convert the indexed array into an associative array. This is much
1028                  * better to remember than plain numbers, isn't it?
1029                  */
1030                 $decodedContent = array(
1031                         // Compressor's extension used to compress the data
1032                         self::PACKAGE_CONTENT_EXTENSION => $decodedContent[self::INDEX_COMPRESSOR_EXTENSION],
1033                         // Package data (aka "message") in BASE64-decoded form but still compressed
1034                         self::PACKAGE_CONTENT_MESSAGE   => base64_decode($decodedContent[self::INDEX_PACKAGE_DATA]),
1035                         // Tags as an indexed array for "tagging" the message
1036                         self::PACKAGE_CONTENT_TAGS      => explode(self::PACKAGE_TAGS_SEPARATOR, $decodedContent[self::INDEX_TAGS]),
1037                         // Checksum of the _decoded_ data
1038                         self::PACKAGE_CONTENT_CHECKSUM  => $decodedContent[self::INDEX_CHECKSUM]
1039                 );
1040
1041                 // Is the checksum valid?
1042                 if (!$this->isChecksumValid($decodedContent, $decodedData)) {
1043                         // Is not the same, so throw an exception here
1044                         throw new InvalidDataChecksumException(array($this, $decodedContent, $decodedData), BaseListener::EXCEPTION_INVALID_DATA_CHECKSUM);
1045                 } // END - if
1046
1047                 /*
1048                  * The checksum is the same, then it can be decompressed safely. The
1049                  * original message is at this point fully decoded.
1050                  */
1051                 $decodedContent[self::PACKAGE_CONTENT_MESSAGE] = $this->getCompressorInstance()->decompressStream($decodedContent[self::PACKAGE_CONTENT_MESSAGE]);
1052
1053                 // And push it on the next stack
1054                 $this->getStackerInstance()->pushNamed(self::STACKER_NAME_NEW_MESSAGE, $decodedContent);
1055         }
1056
1057         /**
1058          * Checks whether a new message has arrived
1059          *
1060          * @return      $hasArrived             Whether a new message has arrived for processing
1061          */
1062         public function isNewMessageArrived () {
1063                 // Determine if the stack is not empty
1064                 $hasArrived = (!$this->getStackerInstance()->isStackEmpty(self::STACKER_NAME_NEW_MESSAGE));
1065
1066                 // Return it
1067                 return $hasArrived;
1068         }
1069
1070         /**
1071          * Handles newly arrived messages
1072          *
1073          * @return      void
1074          * @todo        Implement verification of all sent tags here?
1075          */
1076         public function handleNewlyArrivedMessage () {
1077                 // Get it from the stacker, it is the full array with the decoded message
1078                 $decodedContent = $this->getStackerInstance()->popNamed(self::STACKER_NAME_NEW_MESSAGE);
1079
1080                 // Now get a filter chain back from factory with given tags array
1081                 $chainInstance = PackageFilterChainFactory::createChainByTagsArray($decodedContent[self::PACKAGE_CONTENT_TAGS]);
1082
1083                 /*
1084                  * Process the message through all filters, note that all other
1085                  * elements from $decodedContent are no longer needed.
1086                  */
1087                 $chainInstance->processMessage($decodedContent[self::PACKAGE_CONTENT_MESSAGE], $this);
1088         }
1089
1090         /**
1091          * Checks whether a processed message is pending for "interpretation"
1092          *
1093          * @return      $isPending      Whether a processed message is pending
1094          */
1095         public function isProcessedMessagePending () {
1096                 // Check it
1097                 $isPending = (!$this->getStackerInstance()->isStackEmpty(self::STACKER_NAME_PROCESSED_MESSAGE));
1098
1099                 // Return it
1100                 return $isPending;
1101         }
1102
1103         /**
1104          * Handle processed messages by "interpreting" the 'message_type' element
1105          *
1106          * @return      void
1107          */
1108         public function handleProcessedMessage () {
1109                 // Get it from the stacker, it is the full array with the processed message
1110                 $messageArray = $this->getStackerInstance()->popNamed(self::STACKER_NAME_PROCESSED_MESSAGE);
1111
1112                 // Create a handler instance from given message type
1113                 $handlerInstance = MessageTypeHandlerFactory::createMessageTypeHandlerInstance($messageArray[self::MESSAGE_ARRAY_TYPE]);
1114
1115                 // Handle message data
1116                 $handlerInstance->handleMessageData($messageArray[self::MESSAGE_ARRAY_DATA], $this);
1117
1118                 die(__METHOD__ . ':messageArray='.print_r($messageArray,true));
1119         }
1120 }
1121
1122 // [EOF]
1123 ?>