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