classes/dbupdater.php

   1 <?php
   2 class DbUpdater {
   3
   4         private $dbh;
   5         private $db_type;
   6         private $need_version;
   7
   8         function __construct($dbh, $db_type, $need_version) {
   9                 $this->dbh = $dbh;
  10                 $this->db_type = $db_type;
  11                 $this->need_version = (int) $need_version;
  12         }
  13
  14         function getSchemaVersion() {
  15                 $result = db_query( "SELECT schema_version FROM ttrss_version");
  16                 return (int) db_fetch_result($result, 0, "schema_version");
  17         }
  18
  19         function isUpdateRequired() {
  20                 return $this->getSchemaVersion() < $this->need_version;
  21         }
  22
  23         function getSchemaLines($version) {
  24                 $filename = "schema/versions/".$this->db_type."/$version.sql";
  25
  26                 if (file_exists($filename)) {
  27                         return explode(";", preg_replace("/[\r\n]/", "", file_get_contents($filename)));
  28                 } else {
  29                         return false;
  30                 }
  31         }
  32
  33         function performUpdateTo($version) {
  34                 if ($this->getSchemaVersion() == $version - 1) {
  35
  36                         $lines = $this->getSchemaLines($version);
  37
  38                         if (is_array($lines)) {
  39
  40                                 db_query( "BEGIN");
  41
  42                                 foreach ($lines as $line) {
  43                                         if (strpos($line, "--") !== 0 && $line) {
  44                                                 db_query( $line);
  45                                         }
  46                                 }
  47
  48                                 $db_version = $this->getSchemaVersion();
  49
  50                                 if ($db_version == $version) {
  51                                         db_query( "COMMIT");
  52                                         return true;
  53                                 } else {
  54                                         db_query( "ROLLBACK");
  55                                         return false;
  56                                 }
  57                         } else {
  58                                 return true;
  59                         }
  60                 } else {
  61                         return false;
  62                 }
  63         }
  64
  65 } ?>