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 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          * Save path for "file database"
  37          */
  38         private $savePath = '';
  39
  40         /**
  41          * The file's extension
  42          */
  43         private $fileExtension = 'serialized';
  44
  45         /**
  46          * The last read file's name
  47          */
  48         private $lastFile = '';
  49
  50         /**
  51          * The last read file's content including header information
  52          */
  53         private $lastContents = array();
  54
  55         /**
  56          * Wether the "connection is already up
  57          */
  58         private $alreadyConnected = false;
  59
  60         /**
  61          * Last error message
  62          */
  63         private $lastError = '';
  64
  65         /**
  66          * Last exception
  67          */
  68         private $lastException = null;
  69
  70         /**
  71          * Table information array
  72          */
  73         private $tableInfo = array();
  74
  75         /**
  76          * Element for index
  77          */
  78         private $indexKey = '__idx';
  79
  80         /**
  81          * The protected constructor. Do never instance from outside! You need to
  82          * set a local file path. The class will then validate it.
  83          *
  84          * @return      void
  85          */
  86         protected function __construct() {
  87                 // Call parent constructor
  88                 parent::__construct(__CLASS__);
  89
  90                 // Clean up a little
  91                 $this->removeNumberFormaters();
  92                 $this->removeSystemArray();
  93         }
  94
  95         /**
  96          * Create an object of LocalFileDatabase and set the save path for local files.
  97          * This method also validates the given file path.
  98          *
  99          * @param               $savePath               The local file path string
 100          * @param               $ioInstance             The input/output handler. This
 101          *                                                              should be FileIoHandler
 102          * @return      $dbInstance                     An instance of LocalFileDatabase
 103          */
 104         public final static function createLocalFileDatabase ($savePath, FileIoHandler $ioInstance) {
 105                 // Get an instance
 106                 $dbInstance = new LocalFileDatabase();
 107
 108                 // Set save path and IO instance
 109                 $dbInstance->setSavePath($savePath);
 110                 $dbInstance->setFileIoInstance($ioInstance);
 111
 112                 // "Connect" to the database
 113                 $dbInstance->connectToDatabase();
 114
 115                 // Return database instance
 116                 return $dbInstance;
 117         }
 118
 119         /**
 120          * Setter for save path
 121          *
 122          * @param               $savePath               The local save path where we shall put our serialized classes
 123          * @return      void
 124          */
 125         public final function setSavePath ($savePath) {
 126                 // Secure string
 127                 $savePath = (string) $savePath;
 128
 129                 // Set save path
 130                 $this->savePath = $savePath;
 131         }
 132
 133         /**
 134          * Getter for save path
 135          *
 136          * @return      $savePath               The local save path where we shall put our serialized classes
 137          */
 138         public final function getSavePath () {
 139                 return $this->savePath;
 140         }
 141
 142         /**
 143          * Getter for last error message
 144          *
 145          * @return      $lastError      Last error message
 146          */
 147         public final function getLastError () {
 148                 return $this->lastError;
 149         }
 150
 151         /**
 152          * Getter for last exception
 153          *
 154          * @return      $lastException  Last thrown exception
 155          */
 156         public final function getLastException () {
 157                 return $this->lastException;
 158         }
 159
 160         /**
 161          * Setter for the last read file
 162          *
 163          * @param       $fqfn   The FQFN of the last read file
 164          * @return      void
 165          */
 166         private final function setLastFile ($fqfn) {
 167                 // Cast string and set it
 168                 $this->lastFile = (string) $fqfn;
 169         }
 170
 171         /**
 172          * Reset the last error and exception instance. This should be done after
 173          * a successfull "query"
 174          *
 175          * @return      void
 176          */
 177         private final function resetLastError () {
 178                 $this->lastError = '';
 179                 $this->lastException = null;
 180         }
 181
 182         /**
 183          * Getter for last read file
 184          *
 185          * @return      $lastFile               The last read file's name with full path
 186          */
 187         public final function getLastFile () {
 188                 return $this->lastFile;
 189         }
 190
 191         /**
 192          * Setter for contents of the last read file
 193          *
 194          * @param               $contents               An array with header and data elements
 195          * @return      void
 196          */
 197         private final function setLastFileContents (array $contents) {
 198                 // Set array
 199                 $this->lastContents = $contents;
 200         }
 201
 202         /**
 203          * Getter for last read file's content as an array
 204          *
 205          * @return      $lastContent    The array with elements 'header' and 'data'.
 206          */
 207         public final function getLastContents () {
 208                 return $this->lastContents;
 209         }
 210
 211         /**
 212          * Getter for file extension
 213          *
 214          * @return      $fileExtension  The array with elements 'header' and 'data'.
 215          */
 216         public final function getFileExtension () {
 217                 return $this->fileExtension;
 218         }
 219
 220         /**
 221          * Getter for index key
 222          *
 223          * @return      $indexKey       Index key
 224          */
 225         public final function getIndexKey () {
 226                 return $this->indexKey;
 227         }
 228
 229         /**
 230          * Reads a local data file  and returns it's contents in an array
 231          *
 232          * @param       $fqfn   The FQFN for the requested file
 233          * @return      $dataArray
 234          */
 235         private function getDataArrayFromFile ($fqfn) {
 236                 // Get a file pointer
 237                 $fileInstance = FrameworkFileInputPointer::createFrameworkFileInputPointer($fqfn);
 238
 239                 // Get the raw data and BASE64-decode it
 240                 $compressedData = base64_decode($fileInstance->readLinesFromFile());
 241
 242                 // Close the file and throw the instance away
 243                 $fileInstance->closeFile();
 244                 unset($fileInstance);
 245
 246                 // Decompress it
 247                 $serializedData = $this->getCompressorChannel()->getCompressor()->decompressStream($compressedData);
 248
 249                 // Unserialize it
 250                 $dataArray = unserialize($serializedData);
 251
 252                 // Finally return it
 253                 return $dataArray;
 254         }
 255
 256         /**
 257          * Writes data array to local file
 258          *
 259          * @param       $fqfn           The FQFN of the local file
 260          * @param       $dataArray      An array with all the data we shall write
 261          * @return      void
 262          */
 263         private function writeDataArrayToFqfn ($fqfn, array $dataArray) {
 264                 // Get a file pointer instance
 265                 $fileInstance = FrameworkFileOutputPointer::createFrameworkFileOutputPointer($fqfn, 'w');
 266
 267                 // Serialize and compress it
 268                 $compressedData = $this->getCompressorChannel()->getCompressor()->compressStream(serialize($dataArray));
 269
 270                 // Write this data BASE64 encoded to the file
 271                 $fileInstance->writeToFile(base64_encode($compressedData));
 272
 273                 // Close the file pointer
 274                 $fileInstance->closeFile();
 275         }
 276
 277         /**
 278          * Getter for table information file contents or an empty if info file was not created
 279          *
 280          * @param       $dataSetInstance        An instance of a database set class
 281          * @return      $infoArray                      An array with all table informations
 282          */
 283         private function getContentsFromTableInfoFile (StoreableCriteria $dataSetInstance) {
 284                 // Default content is no data
 285                 $infoArray = array();
 286
 287                 // Create FQFN for getting the table information file
 288                 $fqfn = $this->generateFqfnFromDataSet($dataSetInstance, 'info');
 289
 290                 // Get the file contents
 291                 try {
 292                         $infoArray = $this->getDataArrayFromFile($fqfn);
 293                 } catch (FileNotFoundException $e) {
 294                         // Not found, so ignore it here
 295                 }
 296
 297                 // ... and return it
 298                 return $infoArray;
 299         }
 300
 301         /**
 302          * Generates an FQFN from given dataset instance and string
 303          *
 304          * @param       $dataSetInstance        An instance of a database set class
 305          * @param       $rowName                        Name of the row
 306          * @return      $fqfn                           The FQFN for this row
 307          */
 308         private function generateFqfnFromDataSet (StorableCriteria $dataSetInstance, $rowName) {
 309                 // This is the FQFN
 310                 $fqfn = $this->getSavePath() . $dataSetInstance->getTableName() . '/' . $rowName . '.' . $this->getFileExtension();
 311
 312                 // Return it
 313                 return $fqfn;
 314         }
 315
 316         /**
 317          * Creates the table info file from given dataset instance
 318          *
 319          * @param       $dataSetInstance        An instance of a database set class
 320          * @return      void
 321          */
 322         private function createTableInfoFile (StoreableCriteria $dataSetInstance) {
 323                 // Create FQFN for creating the table information file
 324                 $fqfn = $this->generateFqfnFromDataSet($dataSetInstance, 'info');
 325
 326                 // Get the data out from dataset in a local array
 327                 $this->tableInfo[$dataSetInstance->getTableName()] = array(
 328                         'primary'      => $dataSetInstance->getPrimaryKey(),
 329                         'created'      => time(),
 330                         'last_updated' => time()
 331                 );
 332
 333                 // Write the data to the file
 334                 $this->writeDataArrayToFqfn($fqfn, $this->tableInfo[$dataSetInstance->getTableName()]);
 335         }
 336
 337         /**
 338          * Updates the primary key information or creates the table info file if not found
 339          *
 340          * @param       $dataSetInstance        An instance of a database set class
 341          * @return      void
 342          */
 343         private function updatePrimaryKey (StoreableCriteria $dataSetInstance) {
 344                 // Get the information array from lower method
 345                 $infoArray = $this->getContentsFromTableInfoFile($dataSetInstance);
 346
 347                 // Is the primary key there?
 348                 if (!isset($this->tableInfo['primary'])) {
 349                         // Then create the info file
 350                         $this->createTableInfoFile($dataSetInstance);
 351                 } elseif (($this->getConfigInstance()->getConfigEntry('db_update_primary_forced') == 'Y') && ($dataSetInstance->getPrimaryKey() != $this->tableInfo['primary'])) {
 352                         // Set the array element
 353                         $this->tableInfo[$dataSetInstance->getTableName()]['primary'] = $dataSetInstance->getPrimaryKey();
 354
 355                         // Update the entry
 356                         $this->updateTableInfoFile($dataSetInstance);
 357                 }
 358         }
 359
 360         /**
 361          * Makes sure that the database connection is alive
 362          *
 363          * @return      void
 364          * @todo        Do some checks on the database directory and files here
 365          */
 366         public function connectToDatabase () {
 367         }
 368
 369         /**
 370          * Starts a SELECT query on the database by given return type, table name
 371          * and search criteria
 372          *
 373          * @param       $resultType             Result type ('array', 'object' and 'indexed' are valid)
 374          * @param       $tableName              Name of the database table
 375          * @param       $criteria               Local search criteria class
 376          * @return      $resultData             Result data of the query
 377          * @throws      UnsupportedCriteriaException    If the criteria is unsupported
 378          * @throws      SqlException                                    If an 'SQL error' occurs
 379          */
 380         public function querySelect ($resultType, $tableName, LocalSearchCriteria $criteriaInstance) {
 381                 // The result is null by any errors
 382                 $resultData = null;
 383
 384                 // Create full path name
 385                 $pathName = $this->getSavePath() . $tableName . '/';
 386
 387                 // A 'select' query is not that easy on local files, so first try to
 388                 // find the 'table' which is in fact a directory on the server
 389                 try {
 390                         // Get a directory pointer instance
 391                         $directoryInstance = FrameworkDirectoryPointer::createFrameworkDirectoryPointer($pathName);
 392
 393                         // Initialize the result data, this need to be rewritten e.g. if a local file cannot be read
 394                         $resultData = array(
 395                                 'status'        => LocalfileDatabase::RESULT_OKAY,
 396                                 'rows'          => array()
 397                         );
 398
 399                         // Initialize limit/skip
 400                         $limitFound = 0;
 401                         $skipFound = 0;
 402                         $idx = 1;
 403
 404                         // Read the directory with some exceptions
 405                         while (($dataFile = $directoryInstance->readDirectoryExcept(array('.', '..', '.htaccess', '.svn', "info." . $this->getFileExtension()))) && ($limitFound < $criteriaInstance->getLimit())) {
 406                                 // Does the extension match?
 407                                 if (substr($dataFile, -(strlen($this->getFileExtension()))) !== $this->getFileExtension()) {
 408                                         // Skip this file!
 409                                         continue;
 410                                 } // END - if
 411
 412                                 // Read the file
 413                                 $dataArray = $this->getDataArrayFromFile($pathName . $dataFile);
 414
 415                                 // Is this an array?
 416                                 if (is_array($dataArray)) {
 417                                         // Search in the criteria with FMFW (First Matches, First Wins)
 418                                         foreach ($dataArray as $key => $value) {
 419                                                 // Get criteria element
 420                                                 $criteria = $criteriaInstance->getCriteriaElemnent($key);
 421
 422                                                 // Is the criteria met?
 423                                                 if ((!is_null($criteria)) && ($criteria == $value))  {
 424
 425                                                         // Shall we skip this entry?
 426                                                         if ($criteriaInstance->getSkip() > 0) {
 427                                                                 // We shall skip some entries
 428                                                                 if ($skipFound < $criteriaInstance->getSkip()) {
 429                                                                         // Skip this entry
 430                                                                         $skipFound++;
 431                                                                         break;
 432                                                                 } // END - if
 433                                                         } // END - if
 434
 435                                                         // Set id number
 436                                                         $dataArray[$this->getIndexKey()] = $idx;
 437
 438                                                         // Entry found!
 439                                                         $resultData['rows'][] = $dataArray;
 440
 441                                                         // Count found entries up
 442                                                         $limitFound++;
 443                                                         break;
 444                                                 } // END - if
 445                                         } // END - foreach
 446                                 } else {
 447                                         // Throw an exception here
 448                                         throw new SqlException(array($this, sprintf("File &#39;%s&#39; contains invalid data.", $dataFile), self::DB_CODE_DATA_FILE_CORRUPT), self::EXCEPTION_SQL_QUERY);
 449                                 }
 450
 451                                 // Count entry up
 452                                 $idx++;
 453                         } // END - while
 454
 455                         // Close directory and throw the instance away
 456                         $directoryInstance->closeDirectory();
 457                         unset($directoryInstance);
 458
 459                         // Reset last error message and exception
 460                         $this->resetLastError();
 461                 } catch (PathIsNoDirectoryException $e) {
 462                         // Path not found means "table not found" for real databases...
 463                         $this->lastException = $e;
 464                         $this->lastError = $e->getMessage();
 465
 466                         // So throw an SqlException here with faked error message
 467                         throw new SqlException (array($this, sprintf("Table &#39;%s&#39; not found", $tableName), self::DB_CODE_TABLE_MISSING), self::EXCEPTION_SQL_QUERY);
 468                 } catch (FrameworkException $e) {
 469                         // Catch all exceptions and store them in last error
 470                         $this->lastException = $e;
 471                         $this->lastError = $e->getMessage();
 472                 }
 473
 474                 // Return the gathered result
 475                 return $resultData;
 476         }
 477
 478         /**
 479          * "Inserts" a data set instance into a local file database folder
 480          *
 481          * @param       $dataSetInstance        A storeable data set
 482          * @return      void
 483          * @throws      SqlException    If an SQL error occurs
 484          */
 485         public function queryInsertDataSet (StoreableCriteria $dataSetInstance) {
 486                 // Create full path name
 487                 $fqfn = $this->generateFqfnFromDataSet($dataSetInstance, md5($dataSetInstance->getUniqueValue()));
 488
 489                 // Try to save the request away
 490                 try {
 491                         // Write the data away
 492                         $this->writeDataArrayToFqfn($fqfn, $dataSetInstance->getCriteriaArray());
 493
 494                         // Update the primary key
 495                         $this->updatePrimaryKey($dataSetInstance);
 496
 497                         // Reset last error message and exception
 498                         $this->resetLastError();
 499                 } catch (FrameworkException $e) {
 500                         // Catch all exceptions and store them in last error
 501                         $this->lastException = $e;
 502                         $this->lastError = $e->getMessage();
 503
 504                         // Throw an SQL exception
 505                         throw new SqlException (array($this, sprintf("Cannot write data to table &#39;%s&#39;", $tableName), self::DB_CODE_TABLE_UNWRITEABLE), self::EXCEPTION_SQL_QUERY);
 506                 }
 507         }
 508
 509         /**
 510          * "Updates" a data set instance with a database layer
 511          *
 512          * @param       $dataSetInstance        A storeable data set
 513          * @return      void
 514          * @throws      SqlException    If an SQL error occurs
 515          */
 516         public function queryUpdateDataSet (StoreableCriteria $dataSetInstance) {
 517                 // Create full path name
 518                 $pathName = $this->getSavePath() . $dataSetInstance->getTableName() . '/';
 519
 520                 // Try all the requests
 521                 try {
 522                         // Get a file pointer instance
 523                         $directoryInstance = FrameworkDirectoryPointer::createFrameworkDirectoryPointer($pathName);
 524
 525                         // Initialize limit/skip
 526                         $limitFound = 0;
 527                         $skipFound = 0;
 528
 529                         // Get the criteria array from the dataset
 530                         $criteriaArray = $dataSetInstance->getCriteriaArray();
 531
 532                         // Get search criteria
 533                         $searchInstance = $dataSetInstance->getSearchInstance();
 534
 535                         // Read the directory with some exceptions
 536                         while (($dataFile = $directoryInstance->readDirectoryExcept(array('.', '..', '.htaccess', '.svn', "info." . $this->getFileExtension()))) && ($limitFound < $searchInstance->getLimit())) {
 537                                 // Does the extension match?
 538                                 if (substr($dataFile, -(strlen($this->getFileExtension()))) !== $this->getFileExtension()) {
 539                                         // Skip this file!
 540                                         continue;
 541                                 }
 542
 543                                 // Open this file for reading
 544                                 $dataArray = $this->getDataArrayFromFile($pathName . $dataFile);
 545
 546                                 // Is this an array?
 547                                 if (is_array($dataArray)) {
 548                                         // Search in the criteria with FMFW (First Matches, First Wins)
 549                                         foreach ($dataArray as $key => $value) {
 550                                                 // Get criteria element
 551                                                 $criteria = $searchInstance->getCriteriaElemnent($key);
 552
 553                                                 // Is the criteria met?
 554                                                 if ((!is_null($criteria)) && ($criteria == $value))  {
 555
 556                                                         // Shall we skip this entry?
 557                                                         if ($searchInstance->getSkip() > 0) {
 558                                                                 // We shall skip some entries
 559                                                                 if ($skipFound < $searchInstance->getSkip()) {
 560                                                                         // Skip this entry
 561                                                                         $skipFound++;
 562                                                                         break;
 563                                                                 } // END - if
 564                                                         } // END - if
 565
 566                                                         // Entry found, so update it
 567                                                         foreach ($criteriaArray as $criteriaKey => $criteriaValue) {
 568                                                                 $dataArray[$criteriaKey] = $criteriaValue;
 569                                                         } // END - foreach
 570
 571                                                         // Write the data to a local file
 572                                                         $this->writeDataArrayToFqfn($pathName . $dataFile, $dataArray);
 573
 574                                                         // Count it
 575                                                         $limitFound++;
 576                                                         break;
 577                                                 } // END - if
 578                                         } // END - foreach
 579                                 } // END - if
 580                         } // END - while
 581
 582                         // Close the file pointer
 583                         $directoryInstance->closeDirectory();
 584
 585                         // Update the primary key
 586                         $this->updatePrimaryKey($dataSetInstance);
 587
 588                         // Reset last error message and exception
 589                         $this->resetLastError();
 590                 } catch (FrameworkException $e) {
 591                         // Catch all exceptions and store them in last error
 592                         $this->lastException = $e;
 593                         $this->lastError = $e->getMessage();
 594
 595                         // Throw an SQL exception
 596                         throw new SqlException (array($this, sprintf("Cannot write data to table &#39;%s&#39;", $dataSetInstance->getTableName()), self::DB_CODE_TABLE_UNWRITEABLE), self::EXCEPTION_SQL_QUERY);
 597                 }
 598         }
 599
 600         /**
 601          * Getter for primary key of specified table or if not found null will be
 602          * returned. This must be database-specific.
 603          *
 604          * @param       $tableName              Name of the table we need the primary key from
 605          * @return      $primaryKey             Primary key column of the given table
 606          */
 607         public function getPrimaryKeyOfTable ($tableName) {
 608                 // Default key is null
 609                 $primaryKey = null;
 610
 611                 // Does the table information exist?
 612                 if (isset($this->tableInfo[$tableName])) {
 613                         // Then return the primary key
 614                         $primaryKey = $this->tableInfo[$tableName]['primary'];
 615                 } // END - if
 616
 617                 // Return the column
 618                 return $primaryKey;
 619         }
 620 }
 621
 622 // [EOF]
 623 ?>