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 BaseDatabaseBackend implements DatabaseBackendInterface {
  27         /**
  28          * The file's extension
  29          */
  30         private $fileExtension = 'serialized';
  31
  32         /**
  33          * The last read file's name
  34          */
  35         private $lastFile = '';
  36
  37         /**
  38          * The last read file's content including header information
  39          */
  40         private $lastContents = array();
  41
  42         /**
  43          * Whether the "connection is already up
  44          */
  45         private $alreadyConnected = false;
  46
  47         /**
  48          * Table information array
  49          */
  50         private $tableInfo = array();
  51
  52         /**
  53          * Element for index
  54          */
  55         private $indexKey = '__idx';
  56
  57         /**
  58          * The protected constructor. Do never instance from outside! You need to
  59          * set a local file path. The class will then validate it.
  60          *
  61          * @return      void
  62          */
  63         protected function __construct () {
  64                 // Call parent constructor
  65                 parent::__construct(__CLASS__);
  66         }
  67
  68         /**
  69          * Create an object of LocalFileDatabase and set the save path from
  70          * configuration for local files.
  71          *
  72          * @return      $databaseInstance       An instance of LocalFileDatabase
  73          */
  74         public static final function createLocalFileDatabase () {
  75                 // Get an instance
  76                 $databaseInstance = new LocalFileDatabase();
  77
  78                 // Get a new compressor channel instance
  79                 $compressorInstance = ObjectFactory::createObjectByConfiguredName('compressor_channel_class');
  80
  81                 // Set the compressor channel
  82                 $databaseInstance->setCompressorChannel($compressorInstance);
  83
  84                 // Get a file IO handler
  85                 $fileIoInstance = ObjectFactory::createObjectByConfiguredName('file_io_class');
  86
  87                 // ... and set it
  88                 $databaseInstance->setFileIoInstance($fileIoInstance);
  89
  90                 // "Connect" to the database
  91                 $databaseInstance->connectToDatabase();
  92
  93                 // Return database instance
  94                 return $databaseInstance;
  95         }
  96
  97         /**
  98          * Setter for the last read file
  99          *
 100          * @param       $fqfn   The FQFN of the last read file
 101          * @return      void
 102          */
 103         private final function setLastFile ($fqfn) {
 104                 // Cast string and set it
 105                 $this->lastFile = (string) $fqfn;
 106         }
 107
 108         /**
 109          * Getter for last read file
 110          *
 111          * @return      $lastFile       The last read file's name with full path
 112          */
 113         public final function getLastFile () {
 114                 return $this->lastFile;
 115         }
 116
 117         /**
 118          * Setter for contents of the last read file
 119          *
 120          * @param               $contents       An array with header and data elements
 121          * @return      void
 122          */
 123         private final function setLastFileContents (array $contents) {
 124                 // Set array
 125                 $this->lastContents = $contents;
 126         }
 127
 128         /**
 129          * Getter for last read file's content as an array
 130          *
 131          * @return      $lastContent    The array with elements 'header' and 'data'.
 132          */
 133         public final function getLastContents () {
 134                 return $this->lastContents;
 135         }
 136
 137         /**
 138          * Getter for file extension
 139          *
 140          * @return      $fileExtension  The array with elements 'header' and 'data'.
 141          */
 142         public final function getFileExtension () {
 143                 return $this->fileExtension;
 144         }
 145
 146         /**
 147          * Getter for index key
 148          *
 149          * @return      $indexKey       Index key
 150          */
 151         public final function getIndexKey () {
 152                 return $this->indexKey;
 153         }
 154
 155         /**
 156          * Reads a local data file  and returns it's contents in an array
 157          *
 158          * @param       $fqfn   The FQFN for the requested file
 159          * @return      $dataArray
 160          */
 161         private function getDataArrayFromFile ($fqfn) {
 162                 // Debug message
 163                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('DATABASE: Reading elements from database file ' . $fqfn . ' ...');
 164
 165                 // Init compressed data
 166                 $compressedData = $this->getFileIoInstance()->loadFileContents($fqfn);
 167                 $compressedData = $compressedData['data'];
 168
 169                 // Close the file and throw the instance away
 170                 unset($fileInstance);
 171
 172                 // Decompress it
 173                 $serializedData = $this->getCompressorChannel()->getCompressor()->decompressStream($compressedData);
 174
 175                 // Unserialize it
 176                 $dataArray = unserialize($serializedData);
 177
 178                 // Debug message
 179                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('DATABASE: Read ' . count($dataArray) . ' elements from database file ' . $fqfn . '.');
 180
 181                 // Finally return it
 182                 return $dataArray;
 183         }
 184
 185         /**
 186          * Writes data array to local file
 187          *
 188          * @param       $fqfn           The FQFN of the local file
 189          * @param       $dataArray      An array with all the data we shall write
 190          * @return      void
 191          */
 192         private function writeDataArrayToFqfn ($fqfn, array $dataArray) {
 193                 // Debug message
 194                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('DATABASE: Flushing ' . count($dataArray) . ' elements to database file ' . $fqfn . ' ...');
 195
 196                 // Serialize and compress it
 197                 $compressedData = $this->getCompressorChannel()->getCompressor()->compressStream(serialize($dataArray));
 198
 199                 // Write data
 200                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('DATABASE: Writing ' . strlen($compressedData) . ' bytes ...');
 201
 202                 // Write this data BASE64 encoded to the file
 203                 $this->getFileIoInstance()->saveFile($fqfn, $compressedData);
 204
 205                 // Debug message
 206                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('DATABASE: Flushing ' . count($dataArray) . ' elements to database file completed.');
 207         }
 208
 209         /**
 210          * Getter for table information file contents or an empty if info file was not created
 211          *
 212          * @param       $dataSetInstance        An instance of a database set class
 213          * @return      $infoArray                      An array with all table informations
 214          */
 215         private function getContentsFromTableInfoFile (StoreableCriteria $dataSetInstance) {
 216                 // Default content is no data
 217                 $infoArray = array();
 218
 219                 // Create FQFN for getting the table information file
 220                 $fqfn = $this->generateFqfnFromDataSet($dataSetInstance, 'info');
 221
 222                 // Get the file contents
 223                 try {
 224                         $infoArray = $this->getDataArrayFromFile($fqfn);
 225                 } catch (FileIoException $e) {
 226                         // Not found, so ignore it here
 227                 }
 228
 229                 // ... and return it
 230                 return $infoArray;
 231         }
 232
 233         /**
 234          * Generates an FQFN from given dataset instance and string
 235          *
 236          * @param       $dataSetInstance        An instance of a database set class
 237          * @param       $rowName                        Name of the row
 238          * @return      $fqfn                           The FQFN for this row
 239          */
 240         private function generateFqfnFromDataSet (Criteria $dataSetInstance, $rowName) {
 241                 // This is the FQFN
 242                 $fqfn = $this->getConfigInstance()->getConfigEntry('local_db_path') . $dataSetInstance->getTableName() . '/' . $rowName . '.' . $this->getFileExtension();
 243
 244                 // Return it
 245                 return $fqfn;
 246         }
 247
 248         /**
 249          * Creates the table info file from given dataset instance
 250          *
 251          * @param       $dataSetInstance        An instance of a database set class
 252          * @return      void
 253          */
 254         private function createTableInfoFile (StoreableCriteria $dataSetInstance) {
 255                 // Create FQFN for creating the table information file
 256                 $fqfn = $this->generateFqfnFromDataSet($dataSetInstance, 'info');
 257
 258                 // Get the data out from dataset in a local array
 259                 $this->tableInfo[$dataSetInstance->getTableName()] = array(
 260                         'primary'      => $dataSetInstance->getPrimaryKey(),
 261                         'created'      => time(),
 262                         'last_updated' => time()
 263                 );
 264
 265                 // Write the data to the file
 266                 $this->writeDataArrayToFqfn($fqfn, $this->tableInfo[$dataSetInstance->getTableName()]);
 267         }
 268
 269         /**
 270          * Updates the primary key information or creates the table info file if not found
 271          *
 272          * @param       $dataSetInstance        An instance of a database set class
 273          * @return      void
 274          */
 275         private function updatePrimaryKey (StoreableCriteria $dataSetInstance) {
 276                 // Get the information array from lower method
 277                 $infoArray = $this->getContentsFromTableInfoFile($dataSetInstance);
 278
 279                 // Is the primary key there?
 280                 if (!isset($this->tableInfo['primary'])) {
 281                         // Then create the info file
 282                         $this->createTableInfoFile($dataSetInstance);
 283                 } elseif (($this->getConfigInstance()->getConfigEntry('db_update_primary_forced') == 'Y') && ($dataSetInstance->getPrimaryKey() != $this->tableInfo['primary'])) {
 284                         // Set the array element
 285                         $this->tableInfo[$dataSetInstance->getTableName()]['primary'] = $dataSetInstance->getPrimaryKey();
 286
 287                         // Update the entry
 288                         $this->updateTableInfoFile($dataSetInstance);
 289                 }
 290         }
 291
 292         /**
 293          * Makes sure that the database connection is alive
 294          *
 295          * @return      void
 296          * @todo        Do some checks on the database directory and files here
 297          */
 298         public function connectToDatabase () {
 299         }
 300
 301         /**
 302          * Starts a SELECT query on the database by given return type, table name
 303          * and search criteria
 304          *
 305          * @param       $tableName              Name of the database table
 306          * @param       $criteria               Local search criteria class
 307          * @return      $resultData             Result data of the query
 308          * @throws      UnsupportedCriteriaException    If the criteria is unsupported
 309          * @throws      SqlException                                    If an 'SQL error' occurs
 310          */
 311         public function querySelect ($tableName, LocalSearchCriteria $criteriaInstance) {
 312                 // The result is null by any errors
 313                 $resultData = NULL;
 314
 315                 // Create full path name
 316                 $pathName = $this->getConfigInstance()->getConfigEntry('local_db_path') . $tableName . '/';
 317
 318                 // A 'select' query is not that easy on local files, so first try to
 319                 // find the 'table' which is in fact a directory on the server
 320                 try {
 321                         // Get a directory pointer instance
 322                         $directoryInstance = FrameworkDirectoryPointer::createFrameworkDirectoryPointer($pathName);
 323
 324                         // Initialize the result data, this need to be rewritten e.g. if a local file cannot be read
 325                         $resultData = array(
 326                                 BaseDatabaseBackend::RESULT_INDEX_STATUS => self::RESULT_OKAY,
 327                                 BaseDatabaseBackend::RESULT_INDEX_ROWS   => array()
 328                         );
 329
 330                         // Initialize limit/skip
 331                         $limitFound = 0;
 332                         $skipFound = 0;
 333                         $idx = 1;
 334
 335                         // Read the directory with some exceptions
 336                         while (($dataFile = $directoryInstance->readDirectoryExcept(array('.', '..', '.htaccess', '.svn', 'info.' . $this->getFileExtension()))) && (($limitFound < $criteriaInstance->getLimit()) || ($criteriaInstance->getLimit() == 0))) {
 337                                 // Does the extension match?
 338                                 if (substr($dataFile, -(strlen($this->getFileExtension()))) !== $this->getFileExtension()) {
 339                                         // Skip this file!
 340                                         continue;
 341                                 } // END - if
 342
 343                                 // Read the file
 344                                 $dataArray = $this->getDataArrayFromFile($pathName . $dataFile);
 345                                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('DATABASE: dataFile=' . $dataFile . ',dataArray='.print_r($dataArray,true));
 346
 347                                 // Is this an array?
 348                                 if (is_array($dataArray)) {
 349                                         // Search in the criteria with FMFW (First Matches, First Wins)
 350                                         foreach ($dataArray as $key => $value) {
 351                                                 // Get criteria element
 352                                                 $criteria = $criteriaInstance->getCriteriaElemnent($key);
 353
 354                                                 // Is the criteria met or none set?
 355                                                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('DATABASE: criteria[' . gettype($criteria) . ']=' . $criteria . ';()=' . strlen($criteria) . ',criteriaInstance()=' . $criteriaInstance->count() . ',value(' . strlen($value) . ')=' . $value);
 356                                                 if (((!is_null($criteria)) && ($criteria == $value)) || ($criteriaInstance->count() == 0))  {
 357                                                         // Shall we skip this entry?
 358                                                         if ($criteriaInstance->getSkip() > 0) {
 359                                                                 // We shall skip some entries
 360                                                                 if ($skipFound < $criteriaInstance->getSkip()) {
 361                                                                         // Skip this entry
 362                                                                         $skipFound++;
 363                                                                         break;
 364                                                                 } // END - if
 365                                                         } // END - if
 366
 367                                                         // Set id number
 368                                                         $dataArray[$this->getIndexKey()] = $idx;
 369
 370                                                         // Entry found!
 371                                                         //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('DATABASE: indexKey=' . $this->getIndexKey() . ',idx=' . $idx . ',dataArray=' . print_r($dataArray, true));
 372                                                         $resultData[BaseDatabaseBackend::RESULT_INDEX_ROWS][] = $dataArray;
 373
 374                                                         // Count found entries up
 375                                                         $limitFound++;
 376                                                         break;
 377                                                 } // END - if
 378                                         } // END - foreach
 379                                 } else {
 380                                         // Throw an exception here
 381                                         throw new SqlException(array($this, sprintf("File &#39;%s&#39; contains invalid data.", $dataFile), self::DB_CODE_DATA_FILE_CORRUPT), self::EXCEPTION_SQL_QUERY);
 382                                 }
 383
 384                                 // Count entry up
 385                                 $idx++;
 386                         } // END - while
 387
 388                         // Close directory and throw the instance away
 389                         $directoryInstance->closeDirectory();
 390                         unset($directoryInstance);
 391
 392                         // Reset last exception
 393                         $this->resetLastException();
 394                 } catch (PathIsNoDirectoryException $e) {
 395                         // Path not found means "table not found" for real databases...
 396                         $this->setLastException($e);
 397
 398                         // So throw an SqlException here with faked error message
 399                         throw new SqlException (array($this, sprintf("Table &#39;%s&#39; not found", $tableName), self::DB_CODE_TABLE_MISSING), self::EXCEPTION_SQL_QUERY);
 400                 } catch (FrameworkException $e) {
 401                         // Catch all exceptions and store them in last error
 402                         $this->setLastException($e);
 403                 }
 404
 405                 // Return the gathered result
 406                 return $resultData;
 407         }
 408
 409         /**
 410          * "Inserts" a data set instance into a local file database folder
 411          *
 412          * @param       $dataSetInstance        A storeable data set
 413          * @return      void
 414          * @throws      SqlException    If an SQL error occurs
 415          */
 416         public function queryInsertDataSet (StoreableCriteria $dataSetInstance) {
 417                 // Create full path name
 418                 $fqfn = $this->generateFqfnFromDataSet($dataSetInstance, md5($dataSetInstance->getUniqueValue()));
 419
 420                 // Try to save the request away
 421                 try {
 422                         // Write the data away
 423                         $this->writeDataArrayToFqfn($fqfn, $dataSetInstance->getCriteriaArray());
 424
 425                         // Update the primary key
 426                         $this->updatePrimaryKey($dataSetInstance);
 427
 428                         // Reset last exception
 429                         $this->resetLastException();
 430                 } catch (FrameworkException $e) {
 431                         // Catch all exceptions and store them in last error
 432                         $this->setLastException($e);
 433
 434                         // Throw an SQL exception
 435                         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);
 436                 }
 437         }
 438
 439         /**
 440          * "Updates" a data set instance with a database layer
 441          *
 442          * @param       $dataSetInstance        A storeable data set
 443          * @return      void
 444          * @throws      SqlException    If an SQL error occurs
 445          */
 446         public function queryUpdateDataSet (StoreableCriteria $dataSetInstance) {
 447                 // Create full path name
 448                 $pathName = $this->getConfigInstance()->getConfigEntry('local_db_path') . $dataSetInstance->getTableName() . '/';
 449
 450                 // Try all the requests
 451                 try {
 452                         // Get a file pointer instance
 453                         $directoryInstance = FrameworkDirectoryPointer::createFrameworkDirectoryPointer($pathName);
 454
 455                         // Initialize limit/skip
 456                         $limitFound = 0;
 457                         $skipFound = 0;
 458
 459                         // Get the criteria array from the dataset
 460                         $criteriaArray = $dataSetInstance->getCriteriaArray();
 461
 462                         // Get search criteria
 463                         $searchInstance = $dataSetInstance->getSearchInstance();
 464
 465                         // Read the directory with some exceptions
 466                         while (($dataFile = $directoryInstance->readDirectoryExcept(array('.', '..', '.htaccess', '.svn', 'info.' . $this->getFileExtension()))) && ($limitFound < $searchInstance->getLimit())) {
 467                                 // Does the extension match?
 468                                 if (substr($dataFile, -(strlen($this->getFileExtension()))) !== $this->getFileExtension()) {
 469                                         // Debug message
 470                                         //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('DATABASE: dataFile=' . $dataFile . ',getFileExtension()=' . $this->getFileExtension() . ' - SKIPPED!');
 471                                         // Skip this file!
 472                                         continue;
 473                                 } // END - if
 474
 475                                 // Open this file for reading
 476                                 $dataArray = $this->getDataArrayFromFile($pathName . $dataFile);
 477                                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('DATABASE: dataFile=' . $dataFile . ',dataArray='.print_r($dataArray,true));
 478
 479                                 // Is this an array?
 480                                 if (is_array($dataArray)) {
 481                                         // Search in the criteria with FMFW (First Matches, First Wins)
 482                                         foreach ($dataArray as $key => $value) {
 483                                                 // Get criteria element
 484                                                 $criteria = $searchInstance->getCriteriaElemnent($key);
 485                                                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('DATABASE: dataFile=' . $dataFile . ',key=' . $key . ',criteria=' . $criteria);
 486
 487                                                 // Is the criteria met?
 488                                                 if (((!is_null($criteria)) && ($criteria == $value)) || ($searchInstance->count() == 0))  {
 489                                                         // Shall we skip this entry?
 490                                                         if ($searchInstance->getSkip() > 0) {
 491                                                                 // We shall skip some entries
 492                                                                 if ($skipFound < $searchInstance->getSkip()) {
 493                                                                         // Skip this entry
 494                                                                         $skipFound++;
 495                                                                         break;
 496                                                                 } // END - if
 497                                                         } // END - if
 498
 499                                                         // Entry found, so update it
 500                                                         foreach ($criteriaArray as $criteriaKey => $criteriaValue) {
 501                                                                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__)->debugOutput('DATABASE: criteriaKey=' . $criteriaKey . ',criteriaValue=' . $criteriaValue);
 502                                                                 $dataArray[$criteriaKey] = $criteriaValue;
 503                                                         } // END - foreach
 504
 505                                                         // Write the data to a local file
 506                                                         $this->writeDataArrayToFqfn($pathName . $dataFile, $dataArray);
 507
 508                                                         // Count it
 509                                                         $limitFound++;
 510                                                         break;
 511                                                 } // END - if
 512                                         } // END - foreach
 513                                 } // END - if
 514                         } // END - while
 515
 516                         // Close the file pointer
 517                         $directoryInstance->closeDirectory();
 518
 519                         // Update the primary key
 520                         $this->updatePrimaryKey($dataSetInstance);
 521
 522                         // Reset last exception
 523                         $this->resetLastException();
 524                 } catch (FrameworkException $e) {
 525                         // Catch all exceptions and store them in last error
 526                         $this->setLastException($e);
 527
 528                         // Throw an SQL exception
 529                         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);
 530                 }
 531         }
 532
 533         /**
 534          * Getter for primary key of specified table or if not found null will be
 535          * returned. This must be database-specific.
 536          *
 537          * @param       $tableName              Name of the table we need the primary key from
 538          * @return      $primaryKey             Primary key column of the given table
 539          */
 540         public function getPrimaryKeyOfTable ($tableName) {
 541                 // Default key is null
 542                 $primaryKey = NULL;
 543
 544                 // Does the table information exist?
 545                 if (isset($this->tableInfo[$tableName])) {
 546                         // Then return the primary key
 547                         $primaryKey = $this->tableInfo[$tableName]['primary'];
 548                 } // END - if
 549
 550                 // Return the column
 551                 return $primaryKey;
 552         }
 553 }
 554
 555 // [EOF]
 556 ?>