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, this is free software
  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
  28         // Constants for MySQL backward-compatiblity (PLEASE FIX THEM!)
  29         const DB_CODE_TABLE_MISSING     = 0x100;
  30         const DB_CODE_TABLE_UNWRITEABLE = 0x101;
  31         const DB_CODE_DATA_FILE_CORRUPT = 0x102;
  32
  33         /**
  34          * Save path for "file database"
  35          */
  36         private $savePath = "";
  37
  38         /**
  39          * The file's extension
  40          */
  41         private $fileExtension = "serialized";
  42
  43         /**
  44          * The last read file's name
  45          */
  46         private $lastFile = "";
  47
  48         /**
  49          * The last read file's content including header information
  50          */
  51         private $lastContents = array();
  52
  53         /**
  54          * Wether the "connection is already up
  55          */
  56         private $alreadyConnected = false;
  57
  58         /**
  59          * Last error message
  60          */
  61         private $lastError = "";
  62
  63         /**
  64          * Last exception
  65          */
  66         private $lastException = null;
  67
  68         /**
  69          * Table information array
  70          */
  71         private $tableInfo = array();
  72
  73         /**
  74          * The protected constructor. Do never instance from outside! You need to
  75          * set a local file path. The class will then validate it.
  76          *
  77          * @return      void
  78          */
  79         protected function __construct() {
  80                 // Call parent constructor
  81                 parent::__construct(__CLASS__);
  82
  83                 // Clean up a little
  84                 $this->removeNumberFormaters();
  85                 $this->removeSystemArray();
  86         }
  87
  88         /**
  89          * Create an object of LocalFileDatabase and set the save path for local files.
  90          * This method also validates the given file path.
  91          *
  92          * @param               $savePath                                       The local file path string
  93          * @param               $ioInstance                             The input/output handler. This
  94          *                                                                      should be FileIoHandler
  95          * @return      $dbInstance                             An instance of LocalFileDatabase
  96          */
  97         public final static function createLocalFileDatabase ($savePath, FileIoHandler $ioInstance) {
  98                 // Get an instance
  99                 $dbInstance = new LocalFileDatabase();
 100
 101                 // Set save path and IO instance
 102                 $dbInstance->setSavePath($savePath);
 103                 $dbInstance->setFileIoInstance($ioInstance);
 104
 105                 // "Connect" to the database
 106                 $dbInstance->connectToDatabase();
 107
 108                 // Return database instance
 109                 return $dbInstance;
 110         }
 111
 112         /**
 113          * Setter for save path
 114          *
 115          * @param               $savePath               The local save path where we shall put our serialized classes
 116          * @return      void
 117          */
 118         public final function setSavePath ($savePath) {
 119                 // Secure string
 120                 $savePath = (string) $savePath;
 121
 122                 // Set save path
 123                 $this->savePath = $savePath;
 124         }
 125
 126         /**
 127          * Getter for save path
 128          *
 129          * @return      $savePath               The local save path where we shall put our serialized classes
 130          */
 131         public final function getSavePath () {
 132                 return $this->savePath;
 133         }
 134
 135         /**
 136          * Getter for last error message
 137          *
 138          * @return      $lastError      Last error message
 139          */
 140         public final function getLastError () {
 141                 return $this->lastError;
 142         }
 143
 144         /**
 145          * Getter for last exception
 146          *
 147          * @return      $lastException  Last thrown exception
 148          */
 149         public final function getLastException () {
 150                 return $this->lastException;
 151         }
 152
 153         /**
 154          * Setter for the last read file
 155          *
 156          * @param       $fqfn   The FQFN of the last read file
 157          * @return      void
 158          */
 159         private final function setLastFile ($fqfn) {
 160                 // Cast string and set it
 161                 $this->lastFile = (string) $fqfn;
 162         }
 163
 164         /**
 165          * Reset the last error and exception instance. This should be done after
 166          * a successfull "query"
 167          *
 168          * @return      void
 169          */
 170         private final function resetLastError () {
 171                 $this->lastError = "";
 172                 $this->lastException = null;
 173         }
 174
 175         /**
 176          * Getter for last read file
 177          *
 178          * @return      $lastFile               The last read file's name with full path
 179          */
 180         public final function getLastFile () {
 181                 return $this->lastFile;
 182         }
 183
 184         /**
 185          * Setter for contents of the last read file
 186          *
 187          * @param               $contents               An array with header and data elements
 188          * @return      void
 189          */
 190         private final function setLastFileContents (array $contents) {
 191                 // Set array
 192                 $this->lastContents = $contents;
 193         }
 194
 195         /**
 196          * Getter for last read file's content as an array
 197          *
 198          * @return      $lastContent    The array with elements 'header' and 'data'.
 199          */
 200         public final function getLastContents () {
 201                 return $this->lastContents;
 202         }
 203
 204         /**
 205          * Getter for file extension
 206          *
 207          * @return      $fileExtension  The array with elements 'header' and 'data'.
 208          */
 209         public final function getFileExtension () {
 210                 return $this->fileExtension;
 211         }
 212
 213         /**
 214          * Reads a local data file  and returns it's contents in an array
 215          *
 216          * @param       $fqfn   The FQFN for the requested file
 217          * @return      $dataArray
 218          */
 219         private function getDataArrayFromFile ($fqfn) {
 220                 // Get a file pointer
 221                 $fileInstance = FrameworkFileInputPointer::createFrameworkFileInputPointer($fqfn);
 222
 223                 // Get the raw data and BASE64-decode it
 224                 $compressedData = base64_decode($fileInstance->readLinesFromFile());
 225
 226                 // Close the file and throw the instance away
 227                 $fileInstance->closeFile();
 228                 unset($fileInstance);
 229
 230                 // Decompress it
 231                 $serializedData = $this->getCompressorChannel()->getCompressor()->decompressStream($compressedData);
 232
 233                 // Unserialize it
 234                 $dataArray = unserialize($serializedData);
 235
 236                 // Finally return it
 237                 return $dataArray;
 238         }
 239
 240         /**
 241          * Writes data array to local file
 242          *
 243          * @param       $fqfn           The FQFN of the local file
 244          * @param       $dataArray      An array with all the data we shall write
 245          * @return      void
 246          */
 247         private function writeDataArrayToFqfn ($fqfn, array $dataArray) {
 248                 // Get a file pointer instance
 249                 $fileInstance = FrameworkFileOutputPointer::createFrameworkFileOutputPointer($fqfn, 'w');
 250
 251                 // Serialize and compress it
 252                 $compressedData = $this->getCompressorChannel()->getCompressor()->compressStream(serialize($dataArray));
 253
 254                 // Write this data BASE64 encoded to the file
 255                 $fileInstance->writeToFile(base64_encode($compressedData));
 256
 257                 // Close the file pointer
 258                 $fileInstance->closeFile();
 259         }
 260
 261         /**
 262          * Getter for table information file contents or an empty if the info file was not created
 263          *
 264          * @param       $dataSetInstance        An instance of a database set class
 265          * @return      $infoArray                      An array with all table informations
 266          */
 267         private function getContentsFromTableInfoFile (StoreableCriteria $dataSetInstance) {
 268                 // Default content is no data
 269                 $infoArray = array();
 270
 271                 // Create FQFN for getting the table information file
 272                 $fqfn = $this->getSavePath() . $dataSetInstance->getTableName() . '/info.' . $this->getFileExtension();
 273
 274                 // Get the file contents
 275                 try {
 276                         $infoArray = $this->getDataArrayFromFile($fqfn);
 277                 } catch (FileNotFoundException $e) {
 278                         // Not found, so ignore it here
 279                 }
 280
 281                 // ... and return it
 282                 return $infoArray;
 283         }
 284
 285         /**
 286          * Creates the table info file from given dataset instance
 287          *
 288          * @param       $dataSetInstance        An instance of a database set class
 289          * @return      void
 290          */
 291         private function createTableInfoFile (StoreableCriteria $dataSetInstance) {
 292                 // Create FQFN for creating the table information file
 293                 $fqfn = $this->getSavePath() . $dataSetInstance->getTableName() . '/info.' . $this->getFileExtension();
 294
 295                 // Get the data out from dataset in a local array
 296                 $this->tableInfo[$dataSetInstance->getTableName()] = array(
 297                         'primary'      => $dataSetInstance->getPrimaryKey(),
 298                         'created'      => time(),
 299                         'last_updated' => time()
 300                 );
 301
 302                 // Write the data to the file
 303                 $this->writeDataArrayToFqfn($fqfn, $this->tableInfo[$dataSetInstance->getTableName()]);
 304         }
 305
 306         /**
 307          * Updates the primary key information or creates the table info file if not found
 308          *
 309          * @param       $dataSetInstance        An instance of a database set class
 310          * @return      void
 311          */
 312         private function updatePrimaryKey (StoreableCriteria $dataSetInstance) {
 313                 // Get the information array from lower method
 314                 $infoArray = $this->getContentsFromTableInfoFile($dataSetInstance);
 315
 316                 // Is the primary key there?
 317                 if (!isset($this->tableInfo['primary'])) {
 318                         // Then create the info file
 319                         $this->createTableInfoFile($dataSetInstance);
 320                 } elseif (($this->getConfigInstance()->readConfig('db_update_primary_forced') === "Y") && ($dataSetInstance->getPrimaryKey() != $this->tableInfo['primary'])) {
 321                         // Set the array element
 322                         $this->tableInfo[$dataSetInstance->getTableName()]['primary'] = $dataSetInstance->getPrimaryKey();
 323
 324                         // Update the entry
 325                         $this->updateTableInfoFile($dataSetInstance);
 326                 }
 327         }
 328
 329         /**
 330          * Makes sure that the database connection is alive
 331          *
 332          * @return      void
 333          * @todo        Do some checks on the database directory and files here
 334          */
 335         public function connectToDatabase () {
 336         }
 337
 338         /**
 339          * Starts a SELECT query on the database by given return type, table name
 340          * and search criteria
 341          *
 342          * @param       $resultType             Result type ("array", "object" and "indexed" are valid)
 343          * @param       $tableName              Name of the database table
 344          * @param       $criteria               Local search criteria class
 345          * @return      $resultData             Result data of the query
 346          * @throws      UnsupportedCriteriaException    If the criteria is unsupported
 347          * @throws      SqlException                                    If an "SQL error" occurs
 348          */
 349         public function querySelect ($resultType, $tableName, LocalSearchCriteria $criteriaInstance) {
 350                 // The result is null by any errors
 351                 $resultData = null;
 352
 353                 // Create full path name
 354                 $pathName = $this->getSavePath() . $tableName . '/';
 355
 356                 // A "select" query is not that easy on local files, so first try to
 357                 // find the "table" which is in fact a directory on the server
 358                 try {
 359                         // Get a directory pointer instance
 360                         $directoryInstance = FrameworkDirectoryPointer::createFrameworkDirectoryPointer($pathName);
 361
 362                         // Initialize the result data, this need to be rewritten e.g. if a local file cannot be read
 363                         $resultData = array(
 364                                 'status'        => "ok",
 365                                 'rows'          => array()
 366                         );
 367
 368                         // Initialize limit/skip
 369                         $limitFound = 0;
 370                         $skipFound = 0;
 371                         $idx = 1;
 372
 373                         // Read the directory with some exceptions
 374                         while (($dataFile = $directoryInstance->readDirectoryExcept(array(".", "..", ".htaccess", ".svn", "info." . $this->getFileExtension()))) && ($limitFound < $criteriaInstance->getLimit())) {
 375                                 // Does the extension match?
 376                                 if (substr($dataFile, -(strlen($this->getFileExtension()))) !== $this->getFileExtension()) {
 377                                         // Skip this file!
 378                                         continue;
 379                                 } // END - if
 380
 381                                 // Read the file
 382                                 $dataArray = $this->getDataArrayFromFile($pathName . $dataFile);
 383
 384                                 // Is this an array?
 385                                 if (is_array($dataArray)) {
 386                                         // Search in the criteria with FMFW (First Matches, First Wins)
 387                                         foreach ($dataArray as $key => $value) {
 388                                                 // Get criteria element
 389                                                 $criteria = $criteriaInstance->getCriteriaElemnent($key);
 390
 391                                                 // Is the criteria met?
 392                                                 if ((!is_null($criteria)) && ($criteria == $value))  {
 393
 394                                                         // Shall we skip this entry?
 395                                                         if ($criteriaInstance->getSkip() > 0) {
 396                                                                 // We shall skip some entries
 397                                                                 if ($skipFound < $criteriaInstance->getSkip()) {
 398                                                                         // Skip this entry
 399                                                                         $skipFound++;
 400                                                                         break;
 401                                                                 } // END - if
 402                                                         } // END - if
 403
 404                                                         // Set id number
 405                                                         $dataArray['__idx'] = $idx;
 406
 407                                                         // Entry found!
 408                                                         $resultData['rows'][] = $dataArray;
 409
 410                                                         // Count found entries up
 411                                                         $limitFound++;
 412                                                         break;
 413                                                 } // END - if
 414                                         } // END - foreach
 415                                 } else {
 416                                         // Throw an exception here
 417                                         throw new SqlException(array($this, sprintf("File &#39;%s&#39; contains invalid data.", $dataFile), self::DB_CODE_DATA_FILE_CORRUPT), self::EXCEPTION_SQL_QUERY);
 418                                 }
 419
 420                                 // Count entry up
 421                                 $idx++;
 422                         } // END - while
 423
 424                         // Close directory and throw the instance away
 425                         $directoryInstance->closeDirectory();
 426                         unset($directoryInstance);
 427
 428                         // Reset last error message and exception
 429                         $this->resetLastError();
 430                 } catch (PathIsNoDirectoryException $e) {
 431                         // Path not found means "table not found" for real databases...
 432                         $this->lastException = $e;
 433                         $this->lastError = $e->getMessage();
 434
 435                         // So throw an SqlException here with faked error message
 436                         throw new SqlException (array($this, sprintf("Table &#39;%s&#39; not found", $tableName), self::DB_CODE_TABLE_MISSING), self::EXCEPTION_SQL_QUERY);
 437                 } catch (FrameworkException $e) {
 438                         // Catch all exceptions and store them in last error
 439                         $this->lastException = $e;
 440                         $this->lastError = $e->getMessage();
 441                 }
 442
 443                 // Return the gathered result
 444                 return $resultData;
 445         }
 446
 447         /**
 448          * "Inserts" a data set instance into a local file database folder
 449          *
 450          * @param       $dataSetInstance        A storeable data set
 451          * @return      void
 452          * @throws      SqlException    If an SQL error occurs
 453          */
 454         public function queryInsertDataSet (StoreableCriteria $dataSetInstance) {
 455                 // Create full path name
 456                 $fqfn = sprintf("%s%s/%s.%s",
 457                         $this->getSavePath(),
 458                         $dataSetInstance->getTableName(),
 459                         md5($dataSetInstance->getUniqueValue()),
 460                         $this->getFileExtension()
 461                 );
 462
 463                 // Try to save the request away
 464                 try {
 465                         // Write the data away
 466                         $this->writeDataArrayToFqfn($fqfn, $dataSetInstance->getCriteriaArray());
 467
 468                         // Update the primary key
 469                         $this->updatePrimaryKey($dataSetInstance);
 470
 471                         // Reset last error message and exception
 472                         $this->resetLastError();
 473                 } catch (FrameworkException $e) {
 474                         // Catch all exceptions and store them in last error
 475                         $this->lastException = $e;
 476                         $this->lastError = $e->getMessage();
 477
 478                         // Throw an SQL exception
 479                         throw new SqlException (array($this, sprintf("Cannot write data to table &#39;%s&#39;", $tableName), self::DB_CODE_TABLE_UNWRITEABLE), self::EXCEPTION_SQL_QUERY);
 480                 }
 481         }
 482
 483         /**
 484          * "Updates" a data set instance with a database layer
 485          *
 486          * @param       $dataSetInstance        A storeable data set
 487          * @return      void
 488          * @throws      SqlException    If an SQL error occurs
 489          */
 490         public function queryUpdateDataSet (StoreableCriteria $dataSetInstance) {
 491                 // Create full path name
 492                 $pathName = $this->getSavePath() . $dataSetInstance->getTableName() . '/';
 493
 494                 // Try all the requests
 495                 try {
 496                         // Get a file pointer instance
 497                         $directoryInstance = FrameworkDirectoryPointer::createFrameworkDirectoryPointer($pathName);
 498
 499                         // Initialize limit/skip
 500                         $limitFound = 0;
 501                         $skipFound = 0;
 502
 503                         // Get the criteria array from the dataset
 504                         $criteriaArray = $dataSetInstance->getCriteriaArray();
 505
 506                         // Get search criteria
 507                         $searchInstance = $dataSetInstance->getSearchInstance();
 508
 509                         // Read the directory with some exceptions
 510                         while (($dataFile = $directoryInstance->readDirectoryExcept(array(".", "..", ".htaccess", ".svn", "info." . $this->getFileExtension()))) && ($limitFound < $searchInstance->getLimit())) {
 511                                 // Does the extension match?
 512                                 if (substr($dataFile, -(strlen($this->getFileExtension()))) !== $this->getFileExtension()) {
 513                                         // Skip this file!
 514                                         continue;
 515                                 }
 516
 517                                 // Open this file for reading
 518                                 $dataArray = $this->getDataArrayFromFile($pathName . $dataFile);
 519
 520                                 // Is this an array?
 521                                 if (is_array($dataArray)) {
 522                                         // Search in the criteria with FMFW (First Matches, First Wins)
 523                                         foreach ($dataArray as $key => $value) {
 524                                                 // Get criteria element
 525                                                 $criteria = $searchInstance->getCriteriaElemnent($key);
 526
 527                                                 // Is the criteria met?
 528                                                 if ((!is_null($criteria)) && ($criteria == $value))  {
 529
 530                                                         // Shall we skip this entry?
 531                                                         if ($searchInstance->getSkip() > 0) {
 532                                                                 // We shall skip some entries
 533                                                                 if ($skipFound < $searchInstance->getSkip()) {
 534                                                                         // Skip this entry
 535                                                                         $skipFound++;
 536                                                                         break;
 537                                                                 } // END - if
 538                                                         } // END - if
 539
 540                                                         // Entry found, so update it
 541                                                         foreach ($criteriaArray as $criteriaKey => $criteriaValue) {
 542                                                                 $dataArray[$criteriaKey] = $criteriaValue;
 543                                                         } // END - foreach
 544
 545                                                         // Write the data to a local file
 546                                                         $this->writeDataArrayToFqfn($pathName . $dataFile, $dataArray);
 547
 548                                                         // Count it
 549                                                         $limitFound++;
 550                                                         break;
 551                                                 } // END - if
 552                                         } // END - foreach
 553                                 } // END - if
 554                         } // END - while
 555
 556                         // Close the file pointer
 557                         $directoryInstance->closeDirectory();
 558
 559                         // Update the primary key
 560                         $this->updatePrimaryKey($dataSetInstance);
 561
 562                         // Reset last error message and exception
 563                         $this->resetLastError();
 564                 } catch (FrameworkException $e) {
 565                         // Catch all exceptions and store them in last error
 566                         $this->lastException = $e;
 567                         $this->lastError = $e->getMessage();
 568
 569                         // Throw an SQL exception
 570                         throw new SqlException (array($this, sprintf("Cannot write data to table &#39;%s&#39;", $dataSetInstance->getTableName()), self::DB_CODE_TABLE_UNWRITEABLE), self::EXCEPTION_SQL_QUERY);
 571                 }
 572         }
 573
 574         /**
 575          * Getter for primary key of specified table or if not found null will be
 576          * returned. This must be database-specific.
 577          *
 578          * @param       $tableName              Name of the table we need the primary key from
 579          * @return      $primaryKey             Primary key column of the given table
 580          */
 581         public function getPrimaryKeyOfTable ($tableName) {
 582                 // Default key is null
 583                 $primaryKey = null;
 584
 585                 // Does the table information exist?
 586                 if (isset($this->tableInfo[$tableName])) {
 587                         // Then return the primary key
 588                         $primaryKey = $this->tableInfo[$tableName]['primary'];
 589                 } // END - if
 590
 591                 // Return the column
 592                 return $primaryKey;
 593         }
 594 }
 595
 596 // [EOF]
 597 ?>