inc/classes/main/database/databases/class_LocalFileDatabase.php

   1 <?php
   2 /**
   3  * Database backend class for storing objects in locally created files.
   4  *
   5  * This class serializes objects and saves them to local files.
   6  *
   7  * @author              Roland Haeder <webmaster@ship-simu.org>
   8  * @version             0.0.0
   9  * @copyright   Copyright (c) 2007, 2008 Roland Haeder, this is free software
  10  * @license             GNU GPL 3.0 or any newer version
  11  * @link                http://www.ship-simu.org
  12  *
  13  * This program is free software: you can redistribute it and/or modify
  14  * it under the terms of the GNU General Public License as published by
  15  * the Free Software Foundation, either version 3 of the License, or
  16  * (at your option) any later version.
  17  *
  18  * This program is distributed in the hope that it will be useful,
  19  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  20  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  21  * GNU General Public License for more details.
  22  *
  23  * You should have received a copy of the GNU General Public License
  24  * along with this program. If not, see <http://www.gnu.org/licenses/>.
  25  */
  26 class LocalFileDatabase extends BaseDatabaseFrontend implements DatabaseFrontendInterface {
  27
  28         // Constants for MySQL backward-compatiblity (PLEASE FIX THEM!)
  29         const DB_CODE_TABLE_MISSING     = 0x100;
  30         const DB_CODE_TABLE_UNWRITEABLE = 0x101;
  31         const DB_CODE_DATA_FILE_CORRUPT = 0x102;
  32
  33         /**
  34          * Save path for "file database"
  35          */
  36         private $savePath = "";
  37
  38         /**
  39          * The file's extension
  40          */
  41         private $fileExtension = "serialized";
  42
  43         /**
  44          * The last read file's name
  45          */
  46         private $lastFile = "";
  47
  48         /**
  49          * The last read file's content including header information
  50          */
  51         private $lastContents = array();
  52
  53         /**
  54          * Wether the "connection is already up
  55          */
  56         private $alreadyConnected = false;
  57
  58         /**
  59          * Last error message
  60          */
  61         private $lastError = "";
  62
  63         /**
  64          * Last exception
  65          */
  66         private $lastException = null;
  67
  68         /**
  69          * Table information array
  70          */
  71         private $tableInfo = array();
  72
  73         /**
  74          * The protected constructor. Do never instance from outside! You need to
  75          * set a local file path. The class will then validate it.
  76          *
  77          * @return      void
  78          */
  79         protected function __construct() {
  80                 // Call parent constructor
  81                 parent::__construct(__CLASS__);
  82
  83                 // Clean up a little
  84                 $this->removeNumberFormaters();
  85                 $this->removeSystemArray();
  86         }
  87
  88         /**
  89          * Create an object of LocalFileDatabase and set the save path for local files.
  90          * This method also validates the given file path.
  91          *
  92          * @param               $savePath                                       The local file path string
  93          * @param               $ioInstance                             The input/output handler. This
  94          *                                                                      should be FileIoHandler
  95          * @return      $dbInstance                             An instance of LocalFileDatabase
  96          */
  97         public final static function createLocalFileDatabase ($savePath, FileIoHandler $ioInstance) {
  98                 // Get an instance
  99                 $dbInstance = new LocalFileDatabase();
 100
 101                 // Set save path and IO instance
 102                 $dbInstance->setSavePath($savePath);
 103                 $dbInstance->setFileIoInstance($ioInstance);
 104
 105                 // "Connect" to the database
 106                 $dbInstance->connectToDatabase();
 107
 108                 // Return database instance
 109                 return $dbInstance;
 110         }
 111
 112         /**
 113          * Setter for save path
 114          *
 115          * @param               $savePath               The local save path where we shall put our serialized classes
 116          * @return      void
 117          */
 118         public final function setSavePath ($savePath) {
 119                 // Secure string
 120                 $savePath = (string) $savePath;
 121
 122                 // Set save path
 123                 $this->savePath = $savePath;
 124         }
 125
 126         /**
 127          * Getter for save path
 128          *
 129          * @return      $savePath               The local save path where we shall put our serialized classes
 130          */
 131         public final function getSavePath () {
 132                 return $this->savePath;
 133         }
 134
 135         /**
 136          * Getter for last error message
 137          *
 138          * @return      $lastError      Last error message
 139          */
 140         public final function getLastError () {
 141                 return $this->lastError;
 142         }
 143
 144         /**
 145          * Getter for last exception
 146          *
 147          * @return      $lastException  Last thrown exception
 148          */
 149         public final function getLastException () {
 150                 return $this->lastException;
 151         }
 152
 153         /**
 154          * Analyses if a unique ID has already been used or not by search in the
 155          * local database folder.
 156          *
 157          * @param       $uniqueID               A unique ID number which shall be checked
 158          *                                                      before it will be used
 159          * @param       $inConstructor  If we got called in a de/con-structor or
 160          *                                                      from somewhere else
 161          * @return      $isUnused               true    = The unique ID was not found in the database,
 162          *                                                      false = It is already in use by an other object
 163          * @throws      NoArrayCreatedException         If explode() fails to create an array
 164          * @throws      InvalidArrayCountException      If the array contains less or
 165          *                                                                      more than two elements
 166          * @deprecated
 167          */
 168         public function isUniqueIdUsed ($uniqueID, $inConstructor = false) {
 169                 // Currently not used... ;-)
 170                 $isUsed = false;
 171
 172                 // Split the unique ID up in path and file name
 173                 $pathFile = explode("@", $uniqueID);
 174
 175                 // Are there two elements? Index 0 is the path, 1 the file name + global extension
 176                 if (!is_array($pathFile)) {
 177                         // No array found
 178                         if ($inConstructor) {
 179                                 return false;
 180                         } else {
 181                                 throw new NoArrayCreatedException(array($this, 'pathFile'), self::EXCEPTION_ARRAY_EXPECTED);
 182                         }
 183                 } elseif (count($pathFile) != 2) {
 184                         // Invalid ID returned!
 185                         if ($inConstructor) {
 186                                 return false;
 187                         } else {
 188                                 throw new InvalidArrayCountException(array($this, 'pathFile', count($pathFile), 2), self::EXCEPTION_ARRAY_HAS_INVALID_COUNT);
 189                         }
 190                 }
 191
 192                 // Create full path name
 193                 $pathName = $this->getSavePath() . $pathFile[0];
 194
 195                 // Check if the file is there with a file handler
 196                 if ($inConstructor) {
 197                         // No exceptions in constructors and destructors!
 198                         $dirInstance = FrameworkDirectoryPointer::createFrameworkDirectoryPointer($pathName, true);
 199
 200                         // Has an object being created?
 201                         if (!is_object($dirInstance)) return false;
 202                 } else {
 203                         // Outside a constructor
 204                         try {
 205                                 $dirInstance = FrameworkDirectoryPointer::createFrameworkDirectoryPointer($pathName);
 206                         } catch (PathIsNoDirectoryException $e) {
 207                                 // Okay, path not found
 208                                 return false;
 209                         }
 210                 }
 211
 212                 // Initialize the search loop
 213                 $isValid = false;
 214                 while ($dataFile = $dirInstance->readDirectoryExcept(array(".", "..", ".htaccess", ".svn", "info." . $this->getFileExtension()))) {
 215                         // Generate FQFN for testing
 216                         $fqfn = sprintf("%s/%s", $pathName, $dataFile);
 217                         $this->setLastFile($fqfn);
 218
 219                         // Get instance for file handler
 220                         $inputHandler = $this->getFileIoInstance();
 221
 222                         // Try to read from it. This makes it sure that the file is
 223                         // readable and a valid database file
 224                         $this->setLastFileContents($inputHandler->loadFileContents($fqfn));
 225
 226                         // Extract filename (= unique ID) from it
 227                         $ID = substr(basename($fqfn), 0, -(strlen($this->getFileExtension()) + 1));
 228
 229                         // Is this the required unique ID?
 230                         if ($ID == $pathFile[1]) {
 231                                 // Okay, already in use!
 232                                 $isUsed = true;
 233                         }
 234                 }
 235
 236                 // Close the directory handler
 237                 $dirInstance->closeDirectory();
 238
 239                 // Now the same for the file...
 240                 return $isUsed;
 241         }
 242
 243         /**
 244          * Setter for the last read file
 245          *
 246          * @param               $fqfn   The FQFN of the last read file
 247          * @return      void
 248          */
 249         private final function setLastFile ($fqfn) {
 250                 // Cast string
 251                 $fqfn = (string) $fqfn;
 252                 $this->lastFile = $fqfn;
 253         }
 254
 255         /**
 256          * Reset the last error and exception instance. This should be done after
 257          * a successfull "query"
 258          *
 259          * @return      void
 260          */
 261         private final function resetLastError () {
 262                 $this->lastError = "";
 263                 $this->lastException = null;
 264         }
 265
 266         /**
 267          * Getter for last read file
 268          *
 269          * @return      $lastFile               The last read file's name with full path
 270          */
 271         public final function getLastFile () {
 272                 return $this->lastFile;
 273         }
 274
 275         /**
 276          * Setter for contents of the last read file
 277          *
 278          * @param               $contents               An array with header and data elements
 279          * @return      void
 280          */
 281         private final function setLastFileContents ($contents) {
 282                 // Cast array
 283                 $contents = (array) $contents;
 284                 $this->lastContents = $contents;
 285         }
 286
 287         /**
 288          * Getter for last read file's content as an array
 289          *
 290          * @return      $lastContent    The array with elements 'header' and 'data'.
 291          */
 292         public final function getLastContents () {
 293                 return $this->lastContents;
 294         }
 295
 296         /**
 297          * Getter for file extension
 298          *
 299          * @return      $fileExtension  The array with elements 'header' and 'data'.
 300          */
 301         public final function getFileExtension () {
 302                 return $this->fileExtension;
 303         }
 304
 305         /**
 306          * Reads a local data file  and returns it's contents in an array
 307          *
 308          * @param       $fqfn   The FQFN for the requested file
 309          * @return      $dataArray
 310          */
 311         private function getDataArrayFromFile ($fqfn) {
 312                 // Get a file pointer
 313                 $fileInstance = FrameworkFileInputPointer::createFrameworkFileInputPointer($fqfn);
 314
 315                 // Get the raw data and BASE64-decode it
 316                 $compressedData = base64_decode($fileInstance->readLinesFromFile());
 317
 318                 // Close the file and throw the instance away
 319                 $fileInstance->closeFile();
 320                 unset($fileInstance);
 321
 322                 // Decompress it
 323                 $serializedData = $this->getCompressorChannel()->getCompressor()->decompressStream($compressedData);
 324
 325                 // Unserialize it
 326                 $dataArray = unserialize($serializedData);
 327
 328                 // Finally return it
 329                 return $dataArray;
 330         }
 331
 332         /**
 333          * Writes data array to local file
 334          *
 335          * @param       $fqfn           The FQFN of the local file
 336          * @param       $dataArray      An array with all the data we shall write
 337          * @return      void
 338          */
 339         private function writeDataArrayToFqfn ($fqfn, array $dataArray) {
 340                 // Get a file pointer instance
 341                 $fileInstance = FrameworkFileOutputPointer::createFrameworkFileOutputPointer($fqfn, 'w');
 342
 343                 // Serialize and compress it
 344                 $compressedData = $this->getCompressorChannel()->getCompressor()->compressStream(serialize($dataArray));
 345
 346                 // Write this data BASE64 encoded to the file
 347                 $fileInstance->writeToFile(base64_encode($compressedData));
 348
 349                 // Close the file pointer
 350                 $fileInstance->closeFile();
 351         }
 352
 353         /**
 354          * Getter for table information file contents or an empty if the info file was not created
 355          *
 356          * @param       $dataSetInstance        An instance of a database set class
 357          * @return      $infoArray                      An array with all table informations
 358          */
 359         private function getContentsFromTableInfoFile (StoreableCriteria $dataSetInstance) {
 360                 // Default content is no data
 361                 $infoArray = array();
 362
 363                 // Create FQFN for getting the table information file
 364                 $fqfn = $this->getSavePath() . $dataSetInstance->getTableName() . '/info.' . $this->getFileExtension();
 365
 366                 // Get the file contents
 367                 try {
 368                         $infoArray = $this->getDataArrayFromFile($fqfn);
 369                 } catch (FileNotFoundException $e) {
 370                         // Not found, so ignore it here
 371                 }
 372
 373                 // ... and return it
 374                 return $infoArray;
 375         }
 376
 377         /**
 378          * Creates the table info file from given dataset instance
 379          *
 380          * @param       $dataSetInstance        An instance of a database set class
 381          * @return      void
 382          */
 383         private function createTableInfoFile (StoreableCriteria $dataSetInstance) {
 384                 // Create FQFN for creating the table information file
 385                 $fqfn = $this->getSavePath() . $dataSetInstance->getTableName() . '/info.' . $this->getFileExtension();
 386
 387                 // Get the data out from dataset in a local array
 388                 $this->tableInfo[$dataSetInstance->getTableName()] = array(
 389                         'primary'      => $dataSetInstance->getPrimaryKey(),
 390                         'created'      => time(),
 391                         'last_updated' => time()
 392                 );
 393
 394                 // Write the data to the file
 395                 $this->writeDataArrayToFqfn($fqfn, $this->tableInfo[$dataSetInstance->getTableName()]);
 396         }
 397
 398         /**
 399          * Updates the primary key information or creates the table info file if not found
 400          *
 401          * @param       $dataSetInstance        An instance of a database set class
 402          * @return      void
 403          */
 404         private function updatePrimaryKey (StoreableCriteria $dataSetInstance) {
 405                 // Get the information array from lower method
 406                 $infoArray = $this->getContentsFromTableInfoFile($dataSetInstance);
 407
 408                 // Is the primary key there?
 409                 if (!isset($this->tableInfo['primary'])) {
 410                         // Then create the info file
 411                         $this->createTableInfoFile($dataSetInstance);
 412                 } elseif (($this->getConfigInstance()->readConfig('db_update_primary_forced') === "Y") && ($dataSetInstance->getPrimaryKey() != $this->tableInfo['primary'])) {
 413                         // Set the array element
 414                         $this->tableInfo[$dataSetInstance->getTableName()]['primary'] = $dataSetInstance->getPrimaryKey();
 415
 416                         // Update the entry
 417                         $this->updateTableInfoFile($dataSetInstance);
 418                 }
 419         }
 420
 421         /**
 422          * Makes sure that the database connection is alive
 423          *
 424          * @return      void
 425          * @todo        Do some checks on the database directory and files here
 426          */
 427         public function connectToDatabase () {
 428         }
 429
 430         /**
 431          * Starts a SELECT query on the database by given return type, table name
 432          * and search criteria
 433          *
 434          * @param       $resultType             Result type ("array", "object" and "indexed" are valid)
 435          * @param       $tableName              Name of the database table
 436          * @param       $criteria               Local search criteria class
 437          * @return      $resultData             Result data of the query
 438          * @throws      UnsupportedCriteriaException    If the criteria is unsupported
 439          * @throws      SqlException                                    If an "SQL error" occurs
 440          */
 441         public function querySelect ($resultType, $tableName, LocalSearchCriteria $criteriaInstance) {
 442                 // The result is null by any errors
 443                 $resultData = null;
 444
 445                 // Create full path name
 446                 $pathName = $this->getSavePath() . $tableName . '/';
 447
 448                 // A "select" query is not that easy on local files, so first try to
 449                 // find the "table" which is in fact a directory on the server
 450                 try {
 451                         // Get a directory pointer instance
 452                         $directoryInstance = FrameworkDirectoryPointer::createFrameworkDirectoryPointer($pathName);
 453
 454                         // Initialize the result data, this need to be rewritten e.g. if a local file cannot be read
 455                         $resultData = array(
 456                                 'status'        => "ok",
 457                                 'rows'          => array()
 458                         );
 459
 460                         // Initialize limit/skip
 461                         $limitFound = 0;
 462                         $skipFound = 0;
 463
 464                         // Read the directory with some exceptions
 465                         while (($dataFile = $directoryInstance->readDirectoryExcept(array(".", "..", ".htaccess", ".svn", "info." . $this->getFileExtension()))) && ($limitFound < $criteriaInstance->getLimit())) {
 466                                 // Does the extension match?
 467                                 if (substr($dataFile, -(strlen($this->getFileExtension()))) !== $this->getFileExtension()) {
 468                                         // Skip this file!
 469                                         continue;
 470                                 }
 471
 472                                 // Read the file
 473                                 $dataArray = $this->getDataArrayFromFile($pathName . $dataFile);
 474
 475                                 // Is this an array?
 476                                 if (is_array($dataArray)) {
 477                                         // Search in the criteria with FMFW (First Matches, First Wins)
 478                                         foreach ($dataArray as $key=>$value) {
 479                                                 // Get criteria element
 480                                                 $criteria = $criteriaInstance->getCriteriaElemnent($key);
 481
 482                                                 // Is the criteria met?
 483                                                 if ((!is_null($criteria)) && ($criteria == $value))  {
 484
 485                                                         // Shall we skip this entry?
 486                                                         if ($criteriaInstance->getSkip() > 0) {
 487                                                                 // We shall skip some entries
 488                                                                 if ($skipFound < $criteriaInstance->getSkip()) {
 489                                                                         // Skip this entry
 490                                                                         $skipFound++;
 491                                                                         break;
 492                                                                 } // END - if
 493                                                         } // END - if
 494
 495                                                         // Entry found!
 496                                                         $resultData['rows'][] = $dataArray;
 497                                                         $limitFound++;
 498                                                         break;
 499                                                 } // END - if
 500                                         } // END - foreach
 501                                 } else {
 502                                         // Throw an exception here
 503                                         throw new SqlException(array($this, sprintf("File &#39;%s&#39; contains invalid data.", $dataFile), self::DB_CODE_DATA_FILE_CORRUPT), self::EXCEPTION_SQL_QUERY);
 504                                 }
 505                         } // END - while
 506
 507                         // Close directory and throw the instance away
 508                         $directoryInstance->closeDirectory();
 509                         unset($directoryInstance);
 510
 511                         // Reset last error message and exception
 512                         $this->resetLastError();
 513                 } catch (PathIsNoDirectoryException $e) {
 514                         // Path not found means "table not found" for real databases...
 515                         $this->lastException = $e;
 516                         $this->lastError = $e->getMessage();
 517
 518                         // So throw an SqlException here with faked error message
 519                         throw new SqlException (array($this, sprintf("Table &#39;%s&#39; not found", $tableName), self::DB_CODE_TABLE_MISSING), self::EXCEPTION_SQL_QUERY);
 520                 } catch (FrameworkException $e) {
 521                         // Catch all exceptions and store them in last error
 522                         $this->lastException = $e;
 523                         $this->lastError = $e->getMessage();
 524                 }
 525
 526                 // Return the gathered result
 527                 return $resultData;
 528         }
 529
 530         /**
 531          * "Inserts" a data set instance into a local file database folder
 532          *
 533          * @param       $dataSetInstance        A storeable data set
 534          * @return      void
 535          * @throws      SqlException    If an SQL error occurs
 536          */
 537         public function queryInsertDataSet (StoreableCriteria $dataSetInstance) {
 538                 // Create full path name
 539                 $fqfn = sprintf("%s%s/%s.%s",
 540                         $this->getSavePath(),
 541                         $dataSetInstance->getTableName(),
 542                         md5($dataSetInstance->getUniqueValue()),
 543                         $this->getFileExtension()
 544                 );
 545
 546                 // Try to save the request away
 547                 try {
 548                         // Write the data away
 549                         $this->writeDataArrayToFqfn($fqfn, $dataSetInstance->getCriteriaArray());
 550
 551                         // Update the primary key
 552                         $this->updatePrimaryKey($dataSetInstance);
 553
 554                         // Reset last error message and exception
 555                         $this->resetLastError();
 556                 } catch (FrameworkException $e) {
 557                         // Catch all exceptions and store them in last error
 558                         $this->lastException = $e;
 559                         $this->lastError = $e->getMessage();
 560
 561                         // Throw an SQL exception
 562                         throw new SqlException (array($this, sprintf("Cannot write data to table &#39;%s&#39;", $tableName), self::DB_CODE_TABLE_UNWRITEABLE), self::EXCEPTION_SQL_QUERY);
 563                 }
 564         }
 565
 566         /**
 567          * "Updates" a data set instance with a database layer
 568          *
 569          * @param       $dataSetInstance        A storeable data set
 570          * @return      void
 571          * @throws      SqlException    If an SQL error occurs
 572          */
 573         public function queryUpdateDataSet (StoreableCriteria $dataSetInstance) {
 574                 // Create full path name
 575                 $pathName = $this->getSavePath() . $dataSetInstance->getTableName() . '/';
 576
 577                 // Try all the requests
 578                 try {
 579                         // Get a file pointer instance
 580                         $directoryInstance = FrameworkDirectoryPointer::createFrameworkDirectoryPointer($pathName);
 581
 582                         // Initialize limit/skip
 583                         $limitFound = 0;
 584                         $skipFound = 0;
 585
 586                         // Get the criteria array from the dataset
 587                         $criteriaArray = $dataSetInstance->getCriteriaArray();
 588
 589                         // Get search criteria
 590                         $searchInstance = $dataSetInstance->getSearchInstance();
 591
 592                         // Read the directory with some exceptions
 593                         while (($dataFile = $directoryInstance->readDirectoryExcept(array(".", "..", ".htaccess", ".svn", "info." . $this->getFileExtension()))) && ($limitFound < $searchInstance->getLimit())) {
 594                                 // Does the extension match?
 595                                 if (substr($dataFile, -(strlen($this->getFileExtension()))) !== $this->getFileExtension()) {
 596                                         // Skip this file!
 597                                         continue;
 598                                 }
 599
 600                                 // Open this file for reading
 601                                 $dataArray = $this->getDataArrayFromFile($pathName . $dataFile);
 602
 603                                 // Is this an array?
 604                                 if (is_array($dataArray)) {
 605                                         // Search in the criteria with FMFW (First Matches, First Wins)
 606                                         foreach ($dataArray as $key=>$value) {
 607                                                 // Get criteria element
 608                                                 $criteria = $searchInstance->getCriteriaElemnent($key);
 609
 610                                                 // Is the criteria met?
 611                                                 if ((!is_null($criteria)) && ($criteria == $value))  {
 612
 613                                                         // Shall we skip this entry?
 614                                                         if ($searchInstance->getSkip() > 0) {
 615                                                                 // We shall skip some entries
 616                                                                 if ($skipFound < $searchInstance->getSkip()) {
 617                                                                         // Skip this entry
 618                                                                         $skipFound++;
 619                                                                         break;
 620                                                                 } // END - if
 621                                                         } // END - if
 622
 623                                                         // Entry found, so update it
 624                                                         foreach ($criteriaArray as $criteriaKey=>$criteriaValue) {
 625                                                                 $dataArray[$criteriaKey] = $criteriaValue;
 626                                                         } // END - foreach
 627
 628                                                         // Write the data to a local file
 629                                                         $this->writeDataArrayToFqfn($pathName . $dataFile, $dataArray);
 630
 631                                                         // Count it
 632                                                         $limitFound++;
 633                                                         break;
 634                                                 } // END - if
 635                                         } // END - foreach
 636                                 } // END - if
 637                         } // END - while
 638
 639                         // Close the file pointer
 640                         $directoryInstance->closeDirectory();
 641
 642                         // Update the primary key
 643                         $this->updatePrimaryKey($dataSetInstance);
 644
 645                         // Reset last error message and exception
 646                         $this->resetLastError();
 647                 } catch (FrameworkException $e) {
 648                         // Catch all exceptions and store them in last error
 649                         $this->lastException = $e;
 650                         $this->lastError = $e->getMessage();
 651
 652                         // Throw an SQL exception
 653                         throw new SqlException (array($this, sprintf("Cannot write data to table &#39;%s&#39;", $dataSetInstance->getTableName()), self::DB_CODE_TABLE_UNWRITEABLE), self::EXCEPTION_SQL_QUERY);
 654                 }
 655         }
 656
 657         /**
 658          * Getter for primary key of specified table or if not found null will be
 659          * returned. This must be database-specific.
 660          *
 661          * @param       $tableName              Name of the table we need the primary key from
 662          * @return      $primaryKey             Primary key column of the given table
 663          */
 664         public function getPrimaryKeyOfTable ($tableName) {
 665                 // Default key is null
 666                 $primaryKey = null;
 667
 668                 // Does the table information exist?
 669                 if (isset($this->tableInfo[$tableName])) {
 670                         // Then return the primary key
 671                         $primaryKey = $this->tableInfo[$tableName]['primary'];
 672                 } // END - if
 673
 674                 // Return the column
 675                 return $primaryKey;
 676         }
 677 }
 678
 679 // [EOF]
 680 ?>