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, 2009 - 2012 Core Developer Team
  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         // Constants for MySQL backward-compatiblity (PLEASE FIX THEM!)
  28         const DB_CODE_TABLE_MISSING     = 0x100;
  29         const DB_CODE_TABLE_UNWRITEABLE = 0x101;
  30         const DB_CODE_DATA_FILE_CORRUPT = 0x102;
  31
  32         // Status results
  33         const RESULT_OKAY = 'ok';
  34
  35         /**
  36          * The file's extension
  37          */
  38         private $fileExtension = 'serialized';
  39
  40         /**
  41          * The last read file's name
  42          */
  43         private $lastFile = '';
  44
  45         /**
  46          * The last read file's content including header information
  47          */
  48         private $lastContents = array();
  49
  50         /**
  51          * Whether the "connection is already up
  52          */
  53         private $alreadyConnected = false;
  54
  55         /**
  56          * Last exception
  57          */
  58         private $lastException = NULL;
  59
  60         /**
  61          * Table information array
  62          */
  63         private $tableInfo = array();
  64
  65         /**
  66          * Element for index
  67          */
  68         private $indexKey = '__idx';
  69
  70         /**
  71          * The protected constructor. Do never instance from outside! You need to
  72          * set a local file path. The class will then validate it.
  73          *
  74          * @return      void
  75          */
  76         protected function __construct () {
  77                 // Call parent constructor
  78                 parent::__construct(__CLASS__);
  79         }
  80
  81         /**
  82          * Create an object of LocalFileDatabase and set the save path from
  83          * configuration for local files.
  84          *
  85          * @return      $databaseInstance       An instance of LocalFileDatabase
  86          */
  87         public static final function createLocalFileDatabase () {
  88                 // Get an instance
  89                 $databaseInstance = new LocalFileDatabase();
  90
  91                 // Get a new compressor channel instance
  92                 $compressorInstance = ObjectFactory::createObjectByConfiguredName('compressor_channel_class');
  93
  94                 // Set the compressor channel
  95                 $databaseInstance->setCompressorChannel($compressorInstance);
  96
  97                 // "Connect" to the database
  98                 $databaseInstance->connectToDatabase();
  99
 100                 // Return database instance
 101                 return $databaseInstance;
 102         }
 103
 104         /**
 105          * Getter for last exception
 106          *
 107          * @return      $lastException  Last thrown exception
 108          */
 109         public final function getLastException () {
 110                 return $this->lastException;
 111         }
 112
 113         /**
 114          * Setter for the last read file
 115          *
 116          * @param       $fqfn   The FQFN of the last read file
 117          * @return      void
 118          */
 119         private final function setLastFile ($fqfn) {
 120                 // Cast string and set it
 121                 $this->lastFile = (string) $fqfn;
 122         }
 123
 124         /**
 125          * Reset the last exception instance. This should be done after a "query"
 126          * was completed without any errors.
 127          *
 128          * @return      void
 129          */
 130         private final function resetLastException () {
 131                 $this->lastException = NULL;
 132         }
 133
 134         /**
 135          * Getter for last read file
 136          *
 137          * @return      $lastFile               The last read file's name with full path
 138          */
 139         public final function getLastFile () {
 140                 return $this->lastFile;
 141         }
 142
 143         /**
 144          * Setter for contents of the last read file
 145          *
 146          * @param               $contents               An array with header and data elements
 147          * @return      void
 148          */
 149         private final function setLastFileContents (array $contents) {
 150                 // Set array
 151                 $this->lastContents = $contents;
 152         }
 153
 154         /**
 155          * Getter for last read file's content as an array
 156          *
 157          * @return      $lastContent    The array with elements 'header' and 'data'.
 158          */
 159         public final function getLastContents () {
 160                 return $this->lastContents;
 161         }
 162
 163         /**
 164          * Getter for file extension
 165          *
 166          * @return      $fileExtension  The array with elements 'header' and 'data'.
 167          */
 168         public final function getFileExtension () {
 169                 return $this->fileExtension;
 170         }
 171
 172         /**
 173          * Getter for index key
 174          *
 175          * @return      $indexKey       Index key
 176          */
 177         public final function getIndexKey () {
 178                 return $this->indexKey;
 179         }
 180
 181         /**
 182          * Reads a local data file  and returns it's contents in an array
 183          *
 184          * @param       $fqfn   The FQFN for the requested file
 185          * @return      $dataArray
 186          */
 187         private function getDataArrayFromFile ($fqfn) {
 188                 // Get a file pointer
 189                 $fileInstance = FrameworkFileInputPointer::createFrameworkFileInputPointer($fqfn);
 190
 191                 // Get the raw data and BASE64-decode it
 192                 $compressedData = base64_decode($fileInstance->readLinesFromFile());
 193
 194                 // Close the file and throw the instance away
 195                 $fileInstance->closeFile();
 196                 unset($fileInstance);
 197
 198                 // Decompress it
 199                 $serializedData = $this->getCompressorChannel()->getCompressor()->decompressStream($compressedData);
 200
 201                 // Unserialize it
 202                 $dataArray = unserialize($serializedData);
 203
 204                 // Finally return it
 205                 return $dataArray;
 206         }
 207
 208         /**
 209          * Writes data array to local file
 210          *
 211          * @param       $fqfn           The FQFN of the local file
 212          * @param       $dataArray      An array with all the data we shall write
 213          * @return      void
 214          */
 215         private function writeDataArrayToFqfn ($fqfn, array $dataArray) {
 216                 // Get a file pointer instance
 217                 $fileInstance = FrameworkFileOutputPointer::createFrameworkFileOutputPointer($fqfn, 'w');
 218
 219                 // Serialize and compress it
 220                 $compressedData = $this->getCompressorChannel()->getCompressor()->compressStream(serialize($dataArray));
 221
 222                 // Write this data BASE64 encoded to the file
 223                 $fileInstance->writeToFile(base64_encode($compressedData));
 224
 225                 // Close the file pointer
 226                 $fileInstance->closeFile();
 227         }
 228
 229         /**
 230          * Getter for table information file contents or an empty if info file was not created
 231          *
 232          * @param       $dataSetInstance        An instance of a database set class
 233          * @return      $infoArray                      An array with all table informations
 234          */
 235         private function getContentsFromTableInfoFile (StoreableCriteria $dataSetInstance) {
 236                 // Default content is no data
 237                 $infoArray = array();
 238
 239                 // Create FQFN for getting the table information file
 240                 $fqfn = $this->generateFqfnFromDataSet($dataSetInstance, 'info');
 241
 242                 // Get the file contents
 243                 try {
 244                         $infoArray = $this->getDataArrayFromFile($fqfn);
 245                 } catch (FileIoException $e) {
 246                         // Not found, so ignore it here
 247                 }
 248
 249                 // ... and return it
 250                 return $infoArray;
 251         }
 252
 253         /**
 254          * Generates an FQFN from given dataset instance and string
 255          *
 256          * @param       $dataSetInstance        An instance of a database set class
 257          * @param       $rowName                        Name of the row
 258          * @return      $fqfn                           The FQFN for this row
 259          */
 260         private function generateFqfnFromDataSet (Criteria $dataSetInstance, $rowName) {
 261                 // This is the FQFN
 262                 $fqfn = $this->getConfigInstance()->getConfigEntry('local_db_path') . $dataSetInstance->getTableName() . '/' . $rowName . '.' . $this->getFileExtension();
 263
 264                 // Return it
 265                 return $fqfn;
 266         }
 267
 268         /**
 269          * Creates the table info file from given dataset instance
 270          *
 271          * @param       $dataSetInstance        An instance of a database set class
 272          * @return      void
 273          */
 274         private function createTableInfoFile (StoreableCriteria $dataSetInstance) {
 275                 // Create FQFN for creating the table information file
 276                 $fqfn = $this->generateFqfnFromDataSet($dataSetInstance, 'info');
 277
 278                 // Get the data out from dataset in a local array
 279                 $this->tableInfo[$dataSetInstance->getTableName()] = array(
 280                         'primary'      => $dataSetInstance->getPrimaryKey(),
 281                         'created'      => time(),
 282                         'last_updated' => time()
 283                 );
 284
 285                 // Write the data to the file
 286                 $this->writeDataArrayToFqfn($fqfn, $this->tableInfo[$dataSetInstance->getTableName()]);
 287         }
 288
 289         /**
 290          * Updates the primary key information or creates the table info file if not found
 291          *
 292          * @param       $dataSetInstance        An instance of a database set class
 293          * @return      void
 294          */
 295         private function updatePrimaryKey (StoreableCriteria $dataSetInstance) {
 296                 // Get the information array from lower method
 297                 $infoArray = $this->getContentsFromTableInfoFile($dataSetInstance);
 298
 299                 // Is the primary key there?
 300                 if (!isset($this->tableInfo['primary'])) {
 301                         // Then create the info file
 302                         $this->createTableInfoFile($dataSetInstance);
 303                 } elseif (($this->getConfigInstance()->getConfigEntry('db_update_primary_forced') == 'Y') && ($dataSetInstance->getPrimaryKey() != $this->tableInfo['primary'])) {
 304                         // Set the array element
 305                         $this->tableInfo[$dataSetInstance->getTableName()]['primary'] = $dataSetInstance->getPrimaryKey();
 306
 307                         // Update the entry
 308                         $this->updateTableInfoFile($dataSetInstance);
 309                 }
 310         }
 311
 312         /**
 313          * Makes sure that the database connection is alive
 314          *
 315          * @return      void
 316          * @todo        Do some checks on the database directory and files here
 317          */
 318         public function connectToDatabase () {
 319         }
 320
 321         /**
 322          * Starts a SELECT query on the database by given return type, table name
 323          * and search criteria
 324          *
 325          * @param       $tableName              Name of the database table
 326          * @param       $criteria               Local search criteria class
 327          * @return      $resultData             Result data of the query
 328          * @throws      UnsupportedCriteriaException    If the criteria is unsupported
 329          * @throws      SqlException                                    If an 'SQL error' occurs
 330          */
 331         public function querySelect ($tableName, LocalSearchCriteria $criteriaInstance) {
 332                 // The result is null by any errors
 333                 $resultData = NULL;
 334
 335                 // Create full path name
 336                 $pathName = $this->getConfigInstance()->getConfigEntry('local_db_path') . $tableName . '/';
 337
 338                 // A 'select' query is not that easy on local files, so first try to
 339                 // find the 'table' which is in fact a directory on the server
 340                 try {
 341                         // Get a directory pointer instance
 342                         $directoryInstance = FrameworkDirectoryPointer::createFrameworkDirectoryPointer($pathName);
 343
 344                         // Initialize the result data, this need to be rewritten e.g. if a local file cannot be read
 345                         $resultData = array(
 346                                 BaseDatabaseFrontend::RESULT_INDEX_STATUS => LocalfileDatabase::RESULT_OKAY,
 347                                 BaseDatabaseFrontend::RESULT_INDEX_ROWS   => array()
 348                         );
 349
 350                         // Initialize limit/skip
 351                         $limitFound = 0;
 352                         $skipFound = 0;
 353                         $idx = 1;
 354
 355                         // Read the directory with some exceptions
 356                         while (($dataFile = $directoryInstance->readDirectoryExcept(array('.', '..', '.htaccess', '.svn', 'info.' . $this->getFileExtension()))) && (($limitFound < $criteriaInstance->getLimit()) || ($criteriaInstance->getLimit() == 0))) {
 357                                 // Does the extension match?
 358                                 if (substr($dataFile, -(strlen($this->getFileExtension()))) !== $this->getFileExtension()) {
 359                                         // Skip this file!
 360                                         continue;
 361                                 } // END - if
 362
 363                                 // Read the file
 364                                 $dataArray = $this->getDataArrayFromFile($pathName . $dataFile);
 365
 366                                 // Is this an array?
 367                                 if (is_array($dataArray)) {
 368                                         // Search in the criteria with FMFW (First Matches, First Wins)
 369                                         foreach ($dataArray as $key => $value) {
 370                                                 // Get criteria element
 371                                                 $criteria = $criteriaInstance->getCriteriaElemnent($key);
 372
 373                                                 // Is the criteria met?
 374                                                 //* NOISY-DEBUG: */ $this->debugOutput('DATABASE: criteria[' . gettype($criteria) . ']=' . $criteria . ',()=' . strlen($criteria) . ',value=' . $value . ',()=' . strlen($value));
 375                                                 if ((!is_null($criteria)) && ($criteria == $value))  {
 376                                                         // Shall we skip this entry?
 377                                                         if ($criteriaInstance->getSkip() > 0) {
 378                                                                 // We shall skip some entries
 379                                                                 if ($skipFound < $criteriaInstance->getSkip()) {
 380                                                                         // Skip this entry
 381                                                                         $skipFound++;
 382                                                                         break;
 383                                                                 } // END - if
 384                                                         } // END - if
 385
 386                                                         // Set id number
 387                                                         $dataArray[$this->getIndexKey()] = $idx;
 388
 389                                                         // Entry found!
 390                                                         //* NOISY-DEBUG: */ $this->debugOutput('DATABASE: indexKey=' . $this->getIndexKey() . ',idx=' . $idx . ',dataArray=' . print_r($dataArray, true));
 391                                                         $resultData[BaseDatabaseFrontend::RESULT_INDEX_ROWS][] = $dataArray;
 392
 393                                                         // Count found entries up
 394                                                         $limitFound++;
 395                                                         break;
 396                                                 } // END - if
 397                                         } // END - foreach
 398                                 } else {
 399                                         // Throw an exception here
 400                                         throw new SqlException(array($this, sprintf("File &#39;%s&#39; contains invalid data.", $dataFile), self::DB_CODE_DATA_FILE_CORRUPT), self::EXCEPTION_SQL_QUERY);
 401                                 }
 402
 403                                 // Count entry up
 404                                 $idx++;
 405                         } // END - while
 406
 407                         // Close directory and throw the instance away
 408                         $directoryInstance->closeDirectory();
 409                         unset($directoryInstance);
 410
 411                         // Reset last exception
 412                         $this->resetLastException();
 413                 } catch (PathIsNoDirectoryException $e) {
 414                         // Path not found means "table not found" for real databases...
 415                         $this->lastException = $e;
 416
 417                         // So throw an SqlException here with faked error message
 418                         throw new SqlException (array($this, sprintf("Table &#39;%s&#39; not found", $tableName), self::DB_CODE_TABLE_MISSING), self::EXCEPTION_SQL_QUERY);
 419                 } catch (FrameworkException $e) {
 420                         // Catch all exceptions and store them in last error
 421                         $this->lastException = $e;
 422                 }
 423
 424                 // Return the gathered result
 425                 return $resultData;
 426         }
 427
 428         /**
 429          * "Inserts" a data set instance into a local file database folder
 430          *
 431          * @param       $dataSetInstance        A storeable data set
 432          * @return      void
 433          * @throws      SqlException    If an SQL error occurs
 434          */
 435         public function queryInsertDataSet (StoreableCriteria $dataSetInstance) {
 436                 // Create full path name
 437                 $fqfn = $this->generateFqfnFromDataSet($dataSetInstance, md5($dataSetInstance->getUniqueValue()));
 438
 439                 // Try to save the request away
 440                 try {
 441                         // Write the data away
 442                         $this->writeDataArrayToFqfn($fqfn, $dataSetInstance->getCriteriaArray());
 443
 444                         // Update the primary key
 445                         $this->updatePrimaryKey($dataSetInstance);
 446
 447                         // Reset last exception
 448                         $this->resetLastException();
 449                 } catch (FrameworkException $e) {
 450                         // Catch all exceptions and store them in last error
 451                         $this->lastException = $e;
 452
 453                         // Throw an SQL exception
 454                         throw new SqlException(array($this, sprintf("Cannot write data to table &#39;%s&#39;, is the table created?", $dataSetInstance->getTableName()), self::DB_CODE_TABLE_UNWRITEABLE), self::EXCEPTION_SQL_QUERY);
 455                 }
 456         }
 457
 458         /**
 459          * "Updates" a data set instance with a database layer
 460          *
 461          * @param       $dataSetInstance        A storeable data set
 462          * @return      void
 463          * @throws      SqlException    If an SQL error occurs
 464          */
 465         public function queryUpdateDataSet (StoreableCriteria $dataSetInstance) {
 466                 // Create full path name
 467                 $pathName = $this->getConfigInstance()->getConfigEntry('local_db_path') . $dataSetInstance->getTableName() . '/';
 468
 469                 // Try all the requests
 470                 try {
 471                         // Get a file pointer instance
 472                         $directoryInstance = FrameworkDirectoryPointer::createFrameworkDirectoryPointer($pathName);
 473
 474                         // Initialize limit/skip
 475                         $limitFound = 0;
 476                         $skipFound = 0;
 477
 478                         // Get the criteria array from the dataset
 479                         $criteriaArray = $dataSetInstance->getCriteriaArray();
 480
 481                         // Get search criteria
 482                         $searchInstance = $dataSetInstance->getSearchInstance();
 483
 484                         // Read the directory with some exceptions
 485                         while (($dataFile = $directoryInstance->readDirectoryExcept(array('.', '..', '.htaccess', '.svn', "info." . $this->getFileExtension()))) && ($limitFound < $searchInstance->getLimit())) {
 486                                 // Does the extension match?
 487                                 if (substr($dataFile, -(strlen($this->getFileExtension()))) !== $this->getFileExtension()) {
 488                                         // Skip this file!
 489                                         continue;
 490                                 }
 491
 492                                 // Open this file for reading
 493                                 $dataArray = $this->getDataArrayFromFile($pathName . $dataFile);
 494
 495                                 // Is this an array?
 496                                 if (is_array($dataArray)) {
 497                                         // Search in the criteria with FMFW (First Matches, First Wins)
 498                                         foreach ($dataArray as $key => $value) {
 499                                                 // Get criteria element
 500                                                 $criteria = $searchInstance->getCriteriaElemnent($key);
 501
 502                                                 // Is the criteria met?
 503                                                 if ((!is_null($criteria)) && ($criteria == $value))  {
 504
 505                                                         // Shall we skip this entry?
 506                                                         if ($searchInstance->getSkip() > 0) {
 507                                                                 // We shall skip some entries
 508                                                                 if ($skipFound < $searchInstance->getSkip()) {
 509                                                                         // Skip this entry
 510                                                                         $skipFound++;
 511                                                                         break;
 512                                                                 } // END - if
 513                                                         } // END - if
 514
 515                                                         // Entry found, so update it
 516                                                         foreach ($criteriaArray as $criteriaKey => $criteriaValue) {
 517                                                                 $dataArray[$criteriaKey] = $criteriaValue;
 518                                                         } // END - foreach
 519
 520                                                         // Write the data to a local file
 521                                                         $this->writeDataArrayToFqfn($pathName . $dataFile, $dataArray);
 522
 523                                                         // Count it
 524                                                         $limitFound++;
 525                                                         break;
 526                                                 } // END - if
 527                                         } // END - foreach
 528                                 } // END - if
 529                         } // END - while
 530
 531                         // Close the file pointer
 532                         $directoryInstance->closeDirectory();
 533
 534                         // Update the primary key
 535                         $this->updatePrimaryKey($dataSetInstance);
 536
 537                         // Reset last exception
 538                         $this->resetLastException();
 539                 } catch (FrameworkException $e) {
 540                         // Catch all exceptions and store them in last error
 541                         $this->lastException = $e;
 542
 543                         // Throw an SQL exception
 544                         throw new SqlException(array($this, sprintf("Cannot write data to table &#39;%s&#39;, is the table created?", $dataSetInstance->getTableName()), self::DB_CODE_TABLE_UNWRITEABLE), self::EXCEPTION_SQL_QUERY);
 545                 }
 546         }
 547
 548         /**
 549          * Getter for primary key of specified table or if not found null will be
 550          * returned. This must be database-specific.
 551          *
 552          * @param       $tableName              Name of the table we need the primary key from
 553          * @return      $primaryKey             Primary key column of the given table
 554          */
 555         public function getPrimaryKeyOfTable ($tableName) {
 556                 // Default key is null
 557                 $primaryKey = NULL;
 558
 559                 // Does the table information exist?
 560                 if (isset($this->tableInfo[$tableName])) {
 561                         // Then return the primary key
 562                         $primaryKey = $this->tableInfo[$tableName]['primary'];
 563                 } // END - if
 564
 565                 // Return the column
 566                 return $primaryKey;
 567         }
 568 }
 569
 570 // [EOF]
 571 ?>