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                 // "Connect" to the database
  93                 $databaseInstance->connectToDatabase();
  94
  95                 // Return database instance
  96                 return $databaseInstance;
  97         }
  98
  99         /**
 100          * Setter for the last read file
 101          *
 102          * @param       $fqfn   The FQFN of the last read file
 103          * @return      void
 104          */
 105         private final function setLastFile ($fqfn) {
 106                 // Cast string and set it
 107                 $this->lastFile = (string) $fqfn;
 108         }
 109
 110         /**
 111          * Getter for last read file
 112          *
 113          * @return      $lastFile       The last read file's name with full path
 114          */
 115         public final function getLastFile () {
 116                 return $this->lastFile;
 117         }
 118
 119         /**
 120          * Setter for contents of the last read file
 121          *
 122          * @param               $contents       An array with header and data elements
 123          * @return      void
 124          */
 125         private final function setLastFileContents (array $contents) {
 126                 // Set array
 127                 $this->lastContents = $contents;
 128         }
 129
 130         /**
 131          * Getter for last read file's content as an array
 132          *
 133          * @return      $lastContent    The array with elements 'header' and 'data'.
 134          */
 135         public final function getLastContents () {
 136                 return $this->lastContents;
 137         }
 138
 139         /**
 140          * Getter for file extension
 141          *
 142          * @return      $fileExtension  The array with elements 'header' and 'data'.
 143          */
 144         public final function getFileExtension () {
 145                 return $this->fileExtension;
 146         }
 147
 148         /**
 149          * Getter for index key
 150          *
 151          * @return      $indexKey       Index key
 152          */
 153         public final function getIndexKey () {
 154                 return $this->indexKey;
 155         }
 156
 157         /**
 158          * Reads a local data file  and returns it's contents in an array
 159          *
 160          * @param       $fqfn   The FQFN for the requested file
 161          * @return      $dataArray
 162          */
 163         private function getDataArrayFromFile ($fqfn) {
 164                 // Debug message
 165                 //* NOISY-DEBUG: */ $this->debugOutput('DATABASE: Reading elements from database file ' . $fqfn . ' ...');
 166
 167                 // Get a file pointer
 168                 $fileInstance = FrameworkFileInputPointer::createFrameworkFileInputPointer($fqfn);
 169
 170                 // Get the raw data and BASE64-decode it
 171                 $compressedData = base64_decode($fileInstance->readLinesFromFile());
 172
 173                 // Close the file and throw the instance away
 174                 $fileInstance->closeFile();
 175                 unset($fileInstance);
 176
 177                 // Decompress it
 178                 $serializedData = $this->getCompressorChannel()->getCompressor()->decompressStream($compressedData);
 179
 180                 // Unserialize it
 181                 $dataArray = unserialize($serializedData);
 182
 183                 // Debug message
 184                 //* NOISY-DEBUG: */ $this->debugOutput('DATABASE: Read ' . count($dataArray) . ' elements from database file ' . $fqfn . '.');
 185
 186                 // Finally return it
 187                 return $dataArray;
 188         }
 189
 190         /**
 191          * Writes data array to local file
 192          *
 193          * @param       $fqfn           The FQFN of the local file
 194          * @param       $dataArray      An array with all the data we shall write
 195          * @return      void
 196          */
 197         private function writeDataArrayToFqfn ($fqfn, array $dataArray) {
 198                 // Debug message
 199                 //* NOISY-DEBUG: */ $this->debugOutput('DATABASE: Flushing ' . count($dataArray) . ' elements to database file ' . $fqfn . ' ...');
 200
 201                 // Get a file pointer instance
 202                 $fileInstance = FrameworkFileOutputPointer::createFrameworkFileOutputPointer($fqfn, 'w');
 203
 204                 // Serialize and compress it
 205                 $compressedData = $this->getCompressorChannel()->getCompressor()->compressStream(serialize($dataArray));
 206
 207                 // Write this data BASE64 encoded to the file
 208                 $fileInstance->writeToFile(base64_encode($compressedData));
 209
 210                 // Close the file pointer
 211                 $fileInstance->closeFile();
 212
 213                 // Debug message
 214                 //* NOISY-DEBUG: */ $this->debugOutput('DATABASE: Flushing ' . count($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 . $dataFile);
 353
 354                                 // Is this an array?
 355                                 if (is_array($dataArray)) {
 356                                         // Search in the criteria with FMFW (First Matches, First Wins)
 357                                         foreach ($dataArray as $key => $value) {
 358                                                 // Get criteria element
 359                                                 $criteria = $criteriaInstance->getCriteriaElemnent($key);
 360
 361                                                 // Is the criteria met or none set?
 362                                                 //* NOISY-DEBUG: */ $this->debugOutput('DATABASE: criteria[' . gettype($criteria) . ']=' . $criteria . ';()=' . strlen($criteria) . ',criteriaInstance()=' . $criteriaInstance->count() . ',value(' . strlen($value) . ')=' . $value);
 363                                                 if (((!is_null($criteria)) && ($criteria == $value)) || ($criteriaInstance->count() == 0))  {
 364                                                         // Shall we skip this entry?
 365                                                         if ($criteriaInstance->getSkip() > 0) {
 366                                                                 // We shall skip some entries
 367                                                                 if ($skipFound < $criteriaInstance->getSkip()) {
 368                                                                         // Skip this entry
 369                                                                         $skipFound++;
 370                                                                         break;
 371                                                                 } // END - if
 372                                                         } // END - if
 373
 374                                                         // Set id number
 375                                                         $dataArray[$this->getIndexKey()] = $idx;
 376
 377                                                         // Entry found!
 378                                                         //* NOISY-DEBUG: */ $this->debugOutput('DATABASE: indexKey=' . $this->getIndexKey() . ',idx=' . $idx . ',dataArray=' . print_r($dataArray, true));
 379                                                         $resultData[BaseDatabaseBackend::RESULT_INDEX_ROWS][] = $dataArray;
 380
 381                                                         // Count found entries up
 382                                                         $limitFound++;
 383                                                         break;
 384                                                 } // END - if
 385                                         } // END - foreach
 386                                 } else {
 387                                         // Throw an exception here
 388                                         throw new SqlException(array($this, sprintf("File &#39;%s&#39; contains invalid data.", $dataFile), self::DB_CODE_DATA_FILE_CORRUPT), self::EXCEPTION_SQL_QUERY);
 389                                 }
 390
 391                                 // Count entry up
 392                                 $idx++;
 393                         } // END - while
 394
 395                         // Close directory and throw the instance away
 396                         $directoryInstance->closeDirectory();
 397                         unset($directoryInstance);
 398
 399                         // Reset last exception
 400                         $this->resetLastException();
 401                 } catch (PathIsNoDirectoryException $e) {
 402                         // Path not found means "table not found" for real databases...
 403                         $this->setLastException($e);
 404
 405                         // So throw an SqlException here with faked error message
 406                         throw new SqlException (array($this, sprintf("Table &#39;%s&#39; not found", $tableName), self::DB_CODE_TABLE_MISSING), self::EXCEPTION_SQL_QUERY);
 407                 } catch (FrameworkException $e) {
 408                         // Catch all exceptions and store them in last error
 409                         $this->setLastException($e);
 410                 }
 411
 412                 // Return the gathered result
 413                 return $resultData;
 414         }
 415
 416         /**
 417          * "Inserts" a data set instance into a local file database folder
 418          *
 419          * @param       $dataSetInstance        A storeable data set
 420          * @return      void
 421          * @throws      SqlException    If an SQL error occurs
 422          */
 423         public function queryInsertDataSet (StoreableCriteria $dataSetInstance) {
 424                 // Create full path name
 425                 $fqfn = $this->generateFqfnFromDataSet($dataSetInstance, md5($dataSetInstance->getUniqueValue()));
 426
 427                 // Try to save the request away
 428                 try {
 429                         // Write the data away
 430                         $this->writeDataArrayToFqfn($fqfn, $dataSetInstance->getCriteriaArray());
 431
 432                         // Update the primary key
 433                         $this->updatePrimaryKey($dataSetInstance);
 434
 435                         // Reset last exception
 436                         $this->resetLastException();
 437                 } catch (FrameworkException $e) {
 438                         // Catch all exceptions and store them in last error
 439                         $this->setLastException($e);
 440
 441                         // Throw an SQL exception
 442                         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);
 443                 }
 444         }
 445
 446         /**
 447          * "Updates" a data set instance with a database layer
 448          *
 449          * @param       $dataSetInstance        A storeable data set
 450          * @return      void
 451          * @throws      SqlException    If an SQL error occurs
 452          */
 453         public function queryUpdateDataSet (StoreableCriteria $dataSetInstance) {
 454                 // Create full path name
 455                 $pathName = $this->getConfigInstance()->getConfigEntry('local_db_path') . $dataSetInstance->getTableName() . '/';
 456
 457                 // Try all the requests
 458                 try {
 459                         // Get a file pointer instance
 460                         $directoryInstance = FrameworkDirectoryPointer::createFrameworkDirectoryPointer($pathName);
 461
 462                         // Initialize limit/skip
 463                         $limitFound = 0;
 464                         $skipFound = 0;
 465
 466                         // Get the criteria array from the dataset
 467                         $criteriaArray = $dataSetInstance->getCriteriaArray();
 468
 469                         // Get search criteria
 470                         $searchInstance = $dataSetInstance->getSearchInstance();
 471
 472                         // Read the directory with some exceptions
 473                         while (($dataFile = $directoryInstance->readDirectoryExcept(array('.', '..', '.htaccess', '.svn', 'info.' . $this->getFileExtension()))) && ($limitFound < $searchInstance->getLimit())) {
 474                                 // Does the extension match?
 475                                 if (substr($dataFile, -(strlen($this->getFileExtension()))) !== $this->getFileExtension()) {
 476                                         // Debug message
 477                                         /* NOISY-DEBUG: */ $this->debugOutput('DATABASE: dataFile=' . $dataFile . ',getFileExtension()=' . $this->getFileExtension());
 478                                         // Skip this file!
 479                                         continue;
 480                                 } // END - if
 481
 482                                 // Open this file for reading
 483                                 $dataArray = $this->getDataArrayFromFile($pathName . $dataFile);
 484
 485                                 // Is this an array?
 486                                 if (is_array($dataArray)) {
 487                                         // Search in the criteria with FMFW (First Matches, First Wins)
 488                                         foreach ($dataArray as $key => $value) {
 489                                                 // Get criteria element
 490                                                 $criteria = $searchInstance->getCriteriaElemnent($key);
 491
 492                                                 // Is the criteria met?
 493                                                 if (((!is_null($criteria)) && ($criteria == $value)) || ($searchInstance->count() == 0))  {
 494                                                         // Shall we skip this entry?
 495                                                         if ($searchInstance->getSkip() > 0) {
 496                                                                 // We shall skip some entries
 497                                                                 if ($skipFound < $searchInstance->getSkip()) {
 498                                                                         // Skip this entry
 499                                                                         $skipFound++;
 500                                                                         break;
 501                                                                 } // END - if
 502                                                         } // END - if
 503
 504                                                         // Entry found, so update it
 505                                                         foreach ($criteriaArray as $criteriaKey => $criteriaValue) {
 506                                                                 $dataArray[$criteriaKey] = $criteriaValue;
 507                                                         } // END - foreach
 508
 509                                                         // Write the data to a local file
 510                                                         $this->writeDataArrayToFqfn($pathName . $dataFile, $dataArray);
 511
 512                                                         // Count it
 513                                                         $limitFound++;
 514                                                         break;
 515                                                 } // END - if
 516                                         } // END - foreach
 517                                 } // END - if
 518                         } // END - while
 519
 520                         // Close the file pointer
 521                         $directoryInstance->closeDirectory();
 522
 523                         // Update the primary key
 524                         $this->updatePrimaryKey($dataSetInstance);
 525
 526                         // Reset last exception
 527                         $this->resetLastException();
 528                 } catch (FrameworkException $e) {
 529                         // Catch all exceptions and store them in last error
 530                         $this->setLastException($e);
 531
 532                         // Throw an SQL exception
 533                         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);
 534                 }
 535         }
 536
 537         /**
 538          * Getter for primary key of specified table or if not found null will be
 539          * returned. This must be database-specific.
 540          *
 541          * @param       $tableName              Name of the table we need the primary key from
 542          * @return      $primaryKey             Primary key column of the given table
 543          */
 544         public function getPrimaryKeyOfTable ($tableName) {
 545                 // Default key is null
 546                 $primaryKey = NULL;
 547
 548                 // Does the table information exist?
 549                 if (isset($this->tableInfo[$tableName])) {
 550                         // Then return the primary key
 551                         $primaryKey = $this->tableInfo[$tableName]['primary'];
 552                 } // END - if
 553
 554                 // Return the column
 555                 return $primaryKey;
 556         }
 557 }
 558
 559 // [EOF]
 560 ?>