framework/main/classes/index/class_BaseIndex.php

   1 <?php
   2 // Own namespace
   3 namespace Org\Mxchange\CoreFramework\Index;
   4
   5 // Import framework stuff
   6 use Org\Mxchange\CoreFramework\Factory\ObjectFactory;
   7 use Org\Mxchange\CoreFramework\Filesystem\File\BaseBinaryFile;
   8 use Org\Mxchange\CoreFramework\Generic\UnsupportedOperationException;
   9 use Org\Mxchange\CoreFramework\Iterator\Filesystem\SeekableWritableFileIterator;
  10 use Org\Mxchange\CoreFramework\Object\BaseFrameworkSystem;
  11 use Org\Mxchange\CoreFramework\Utils\String\StringUtils;
  12
  13 // Import SPL stuff
  14 use \SplFileInfo;
  15 use \UnexpectedValueException;
  16
  17 /**
  18  * A general index class
  19  *
  20  * @author              Roland Haeder <webmaster@ship-simu.org>
  21  * @version             0.0.0
  22  * @copyright   Copyright (c) 2007, 2008 Roland Haeder, 2009 - 2020 Core Developer Team
  23  * @license             GNU GPL 3.0 or any newer version
  24  * @link                http://www.ship-simu.org
  25  *
  26  * This program is free software: you can redistribute it and/or modify
  27  * it under the terms of the GNU General Public License as published by
  28  * the Free Software Foundation, either version 3 of the License, or
  29  * (at your option) any later version.
  30  *
  31  * This program is distributed in the hope that it will be useful,
  32  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  33  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  34  * GNU General Public License for more details.
  35  *
  36  * You should have received a copy of the GNU General Public License
  37  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  38  */
  39 abstract class BaseIndex extends BaseFrameworkSystem {
  40         /**
  41          * Magic for this index
  42          */
  43         const INDEX_MAGIC = 'INDEXv0.1';
  44
  45         /**
  46          * Separator group->hash
  47          */
  48         const SEPARATOR_GROUP_HASH = 0x01;
  49
  50         /**
  51          * Separator hash->gap position
  52          */
  53         const SEPARATOR_HASH_GAP_POSITION = 0x02;
  54
  55         /**
  56          * Separator gap position->length
  57          */
  58         const SEPARATOR_GAP_LENGTH = 0x03;
  59
  60         /**
  61          * Protected constructor
  62          *
  63          * @param       $className      Name of the class
  64          * @return      void
  65          */
  66         protected function __construct (string $className) {
  67                 // Call parent constructor
  68                 parent::__construct($className);
  69         }
  70
  71         /**
  72          * Reads the file header
  73          *
  74          * @return      void
  75          * @throws      UnexpectedValueException        If header length is invalid
  76          */
  77         public function readFileHeader () {
  78                 // First rewind to beginning as the header sits at the beginning ...
  79                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('BASE-INDEX: CALLED!');
  80                 $this->getIteratorInstance()->rewind();
  81
  82                 // Then read it (see constructor for calculation)
  83                 $data = $this->getIteratorInstance()->read($this->getIteratorInstance()->getHeaderSize());
  84
  85                 // Have all requested bytes been read?
  86                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('Read %d bytes (%d wanted).', strlen($data), $this->getIteratorInstance()->getHeaderSize()));
  87                 if (strlen($data) != $this->getIteratorInstance()->getHeaderSize()) {
  88                         // Invalid header length
  89                         throw new UnexpectedValueException(sprintf('data(%d)=%s is not expected length %d',
  90                                 strlen($data),
  91                                 $data,
  92                                 $this->getIteratorInstance()->getHeaderSize()
  93                         ));
  94                 } elseif (substr($data, -1, 1) != chr(BaseBinaryFile::SEPARATOR_HEADER_ENTRIES)) {
  95                         // Bad last character
  96                         throw new UnexpectedValueException(sprintf('data=%s does not end with "%s"',
  97                                 $data,
  98                                 chr(BaseBinaryFile::SEPARATOR_HEADER_ENTRIES)
  99                         ));
 100                 }
 101
 102                 // Okay, then remove it
 103                 $data = substr($data, 0, -1);
 104
 105                 // And update seek position
 106                 $this->getIteratorInstance()->updateSeekPosition();
 107
 108                 /*
 109                  * Now split it:
 110                  *
 111                  * 0 => magic
 112                  * 1 => total entries
 113                  */
 114                 $header = explode(chr(BaseBinaryFile::SEPARATOR_HEADER_DATA), $data);
 115
 116                 // Set it here
 117                 $this->getIteratorInstance()->setHeader($header);
 118
 119                 // Check if the array has only 3 elements
 120                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('header(%d)=%s', count($header), print_r($header, true)));
 121                 assert(count($header) == 2);
 122
 123                 // Check magic
 124                 assert($header[0] == self::INDEX_MAGIC);
 125
 126                 // Check length of count
 127                 assert(strlen($header[1]) == BaseBinaryFile::LENGTH_COUNT);
 128
 129                 // Decode count
 130                 $header[1] = hex2bin($header[1]);
 131
 132                 // Trace message
 133                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('BASE-INDEX: EXIT!');
 134         }
 135
 136         /**
 137          * Flushes the file header
 138          *
 139          * @return      void
 140          */
 141         public function flushFileHeader () {
 142                 // Put all informations together
 143                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('BASE-INDEX: CALLED!');
 144                 $header = sprintf('%s%s%s%s',
 145                         // Magic
 146                         self::INDEX_MAGIC,
 147
 148                         // Separator header data
 149                         chr(BaseBinaryFile::SEPARATOR_HEADER_DATA),
 150
 151                         // Total entries
 152                         str_pad(StringUtils::dec2hex($this->getIteratorInstance()->getCounter()), BaseBinaryFile::LENGTH_COUNT, '0', STR_PAD_LEFT),
 153
 154                         // Separator header<->entries
 155                         chr(BaseBinaryFile::SEPARATOR_HEADER_ENTRIES)
 156                 );
 157
 158                 // Write it to disk (header is always at seek position 0)
 159                 $this->getIteratorInstance()->writeData(0, $header, false);
 160
 161                 // Trace message
 162                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('BASE-INDEX: EXIT!');
 163         }
 164
 165         /**
 166          * Initializes this index
 167          *
 168          * @param       $fileInfoInstance       An instance of a SplFileInfo class
 169          * @return      void
 170          * @todo        Currently the index file is not cached, please implement a memory-handling class and if enough RAM is found, cache the whole index file.
 171          */
 172         protected function initIndex (SplFileInfo $fileInfoInstance) {
 173                 // Get a file i/o pointer instance for index file
 174                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('fileInfoInstance=%s - CALLED!', $fileInfoInstance));
 175                 $fileInstance = ObjectFactory::createObjectByConfiguredName('index_file_class', array($fileInfoInstance, $this));
 176
 177                 // Get iterator instance
 178                 $iteratorInstance = ObjectFactory::createObjectByConfiguredName('file_iterator_class', array($fileInstance));
 179
 180                 // Set iterator here
 181                 $this->setIteratorInstance($iteratorInstance);
 182
 183                 // Calculate header size
 184                 $this->getIteratorInstance()->setHeaderSize(
 185                         strlen(self::INDEX_MAGIC) +
 186                         strlen(chr(BaseBinaryFile::SEPARATOR_HEADER_DATA)) +
 187                         BaseBinaryFile::LENGTH_COUNT +
 188                         strlen(chr(BaseBinaryFile::SEPARATOR_HEADER_ENTRIES))
 189                 );
 190
 191                 // Init counters and gaps array
 192                 $this->getIteratorInstance()->initCountersGapsArray();
 193
 194                 // Is the file's header initialized?
 195                 if (!$this->getIteratorInstance()->isFileHeaderInitialized()) {
 196                         // No, then create it (which may pre-allocate the index)
 197                         $this->getIteratorInstance()->createFileHeader();
 198
 199                         // And pre-allocate a bit
 200                         $this->getIteratorInstance()->preAllocateFile('index');
 201                 }
 202
 203                 // Load the file header
 204                 $this->readFileHeader();
 205
 206                 // Count all entries in file
 207                 $this->getIteratorInstance()->analyzeFile();
 208
 209                 // Trace message
 210                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('BASE-INDEX: EXIT!');
 211         }
 212
 213         /**
 214          * Calculates minimum length for one entry/block
 215          *
 216          * @return      $length         Minimum length for one entry/block
 217          */
 218         public function calculateMinimumBlockLength () {
 219                 // Calulcate it
 220                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('BASE-INDEX: CALLED!');
 221                 $length = BaseBinaryFile::LENGTH_TYPE + strlen(chr(BaseBinaryFile::SEPARATOR_TYPE_POSITION)) + BaseBinaryFile::LENGTH_POSITION + strlen(chr(BaseBinaryFile::SEPARATOR_ENTRIES));
 222
 223                 // Return it
 224                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-INDEX: length=%d - EXIT!', $length));
 225                 return $length;
 226         }
 227
 228         /**
 229          * Determines whether the EOF has been reached
 230          *
 231          * @return      $isEndOfFileReached             Whether the EOF has been reached
 232          * @throws      UnsupportedOperationException   If this method is called
 233          */
 234         public function isEndOfFileReached () {
 235                 throw new UnsupportedOperationException(array($this, __FUNCTION__), self::EXCEPTION_UNSPPORTED_OPERATION);
 236         }
 237
 238         /**
 239          * Initializes counter for valid entries, arrays for damaged entries and
 240          * an array for gap seek positions. If you call this method on your own,
 241          * please re-analyze the file structure. So you are better to call
 242          * analyzeFile() instead of this method.
 243          *
 244          * @return      void
 245          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 246          */
 247         public function initCountersGapsArray () {
 248                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 249         }
 250
 251         /**
 252          * Getter for header size
 253          *
 254          * @return      $totalEntries   Size of file header
 255          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 256          */
 257         public final function getHeaderSize () {
 258                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 259         }
 260
 261         /**
 262          * Setter for header size
 263          *
 264          * @param       $headerSize             Size of file header
 265          * @return      void
 266          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 267          */
 268         public final function setHeaderSize (int $headerSize) {
 269                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 270         }
 271
 272         /**
 273          * Getter for header array
 274          *
 275          * @return      $totalEntries   Size of file header
 276          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 277          */
 278         public final function getHeader () {
 279                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 280         }
 281
 282         /**
 283          * Setter for header
 284          *
 285          * @param       $header         Array for a file header
 286          * @return      void
 287          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 288          */
 289         public final function setHeader (array $header) {
 290                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 291         }
 292
 293         /**
 294          * Updates seekPosition attribute from file to avoid to much access on file.
 295          *
 296          * @return      void
 297          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 298          */
 299         public function updateSeekPosition () {
 300                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 301         }
 302
 303         /**
 304          * Getter for total entries
 305          *
 306          * @return      $totalEntries   Total entries in this file
 307          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 308          */
 309         public final function getCounter () {
 310                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 311         }
 312
 313         /**
 314          * "Getter" for file size
 315          *
 316          * @return      $fileSize       Size of currently loaded file
 317          */
 318         public function getFileSize () {
 319                 // Call iterator's method
 320                 return $this->getIteratorInstance()->getFileSize();
 321         }
 322
 323         /**
 324          * Writes data at given position
 325          *
 326          * @param       $seekPosition   Seek position
 327          * @param       $data                   Data to be written
 328          * @param       $flushHeader    Whether to flush the header (default: flush)
 329          * @return      void
 330          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 331          */
 332         public function writeData (int $seekPosition, string $data, bool $flushHeader = true) {
 333                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('seekPosition=%s,data[]=%s,flushHeader=%d - CALLED!', $seekPosition, gettype($data), intval($flushHeader)));
 334                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 335         }
 336
 337         /**
 338          * Writes given value to the file and returns a hash and gap position for it
 339          *
 340          * @param       $groupId        Group identifier
 341          * @param       $value          Value to be added to the stack
 342          * @return      $data           Hash and gap position
 343          * @throws      UnsupportedOperationException   If this method is called
 344          */
 345         public function writeValueToFile (string $groupId, $value) {
 346                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('groupId=%s,value[%s]=%s - CALLED!', $groupId, gettype($value), print_r($value, true)));
 347                 throw new UnsupportedOperationException(array($this, __FUNCTION__), self::EXCEPTION_UNSPPORTED_OPERATION);
 348         }
 349
 350         /**
 351          * Writes given raw data to the file and returns a gap position and length
 352          *
 353          * @param       $groupId        Group identifier
 354          * @param       $hash           Hash from encoded value
 355          * @param       $encoded        Encoded value to be written to the file
 356          * @return      $data           Gap position and length of the raw data
 357          */
 358         public function writeDataToFreeGap (string $groupId, string $hash, string $encoded) {
 359                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('groupId=%s,hash=%s,encoded()=%d - CALLED!', $groupId, $hash, strlen($encoded)));
 360                 throw new UnsupportedOperationException(array($this, __FUNCTION__), self::EXCEPTION_UNSPPORTED_OPERATION);
 361         }
 362
 363 }