DMBridgeVersion.php

<?php
#
# dmBridge: a data access framework for CONTENTdm(R)
#
# Copyright © 2009, 2010, 2011 Board of Regents of the Nevada System of Higher
# Education, on behalf of the University of Nevada, Las Vegas
#

abstract class DMBridgeVersion {

   const DMBRIDGE_VERSION_URL = "http://digital.library.unlv.edu/versions/dmbridge.php";

   private static function getVersionFilePathname() {
      return dirname(__FILE__) . "/../VERSION.txt";
   }

   private static function parseVersionFile($file, &$version, &$seq) {
      if (file_exists($file)) {
         $data = file_get_contents($file);
         $tmp = explode("\n", $data);
         $version = (string) substr($tmp[0], 0, 20);
         $seq = (int) substr($tmp[1], 0, 3);
      }
   }

   public static function getHTTPAPIVersions() {
      return array(1);
   }

   public static function getLatestHTTPAPIVersion() {
      return max(self::getHTTPAPIVersions());;
   }

   public static function getDmBridgeVersion() {
      $version = $seq = 0;
      self::parseVersionFile(self::getVersionFilePathname(), $version, $seq);
      return $version;
   }

   public static function getDmBridgeVersionSequence() {
      $version = $seq = 0;
      self::parseVersionFile(self::getVersionFilePathname(), $version, $seq);
      return $seq;
   }

   public static function getCurrentDmBridgeVersionSequence(DMHTTPRequest $req) {
      $req->setURI(new DMURI(self::DMBRIDGE_VERSION_URL));
      $client = new DMHTTPClient($req);
      $response = $client->send();
      return (int) substr($response->getRepresentation()->getBody(), 0, 4);
   }

   public static function isNewerDmBridgeVersionAvailable(DMHTTPRequest $req) {
      if (file_exists(self::getVersionFilePathname())) {
         return (self::getDmBridgeVersionSequence()
            < self::getCurrentDmBridgeVersionSequence($req));
      }
      return false;
   }

}