XHTMLCompiler/Page.php

   1 <?php
   2
   3 /**
   4  * Represents a page in our content management system. This is loosely
   5  * bound to the filesystem, although it doesn't actually refer to a
   6  * specific file, just a class of files.
   7  */
   8 class XHTMLCompiler_Page
   9 {
  10
  11     /**
  12      * Filename identifier of this page without extension
  13      */
  14     protected $pathStem;
  15
  16     /** File extension of source files (no period) */
  17     protected $sourceExt = 'xhtml';
  18     /** File extension of cache/served files */
  19     protected $cacheExt = 'html';
  20     /** File extension of dependency files */
  21     protected $depsExt = 'xc-deps';
  22
  23     /** Instance of XHTMLCompiler_File for source file */
  24     protected $source;
  25     /** Instance of XHTMLCompiler_File for cache file */
  26     protected $cache;
  27     /** Instance of XHTMLCompiler_File for dependency file */
  28     protected $deps;
  29
  30     /** Instance of XHTMLCompiler_Directory for all of the above files*/
  31     protected $dir;
  32
  33     /**
  34      * Constructs a page object, validates filename for correctness
  35      * @param $path String path filename, can be from untrusted source
  36      * @param $mute Whether or not to stop the class from complaining when
  37      *              the source file doesn't exist. This is a stopgap measure,
  38      *              please replace with better exception handling.
  39      * @todo Cleanup into subroutines
  40      * @todo Factor out allowed_directories realpath'ing to config class
  41      */
  42     public function __construct($path, $mute = false) {
  43
  44         $xc  = XHTMLCompiler::getInstance();
  45         $php = XHTMLCompiler::getPHPWrapper();
  46
  47         // test file extension
  48         $info = pathinfo($path);
  49         if (
  50             empty($info['extension']) || (
  51                 $info['extension'] !== $this->sourceExt &&
  52                 $info['extension'] !== $this->cacheExt
  53             )
  54         ) {
  55             throw new XHTMLCompiler_Exception(403, 'Forbidden extension',
  56               'File extension cannot be processed by XHTML Compiler, check
  57               for faulty <code>.htaccess</code> rules.');
  58         }
  59
  60         // test for directory's existence and resolve to real path
  61         $dir = $info['dirname'];
  62         if ($dir == '.') $dir .= '/';
  63         $dir = $php->realpath($dir);
  64         if ($dir === false) {
  65             throw new XHTMLCompiler_Exception(404, 'Missing directory',
  66                 'Requested directory cannot be found; check your file
  67                 path and try again.' );
  68         }
  69         if ($dir[strlen($dir)-1] == '/') $dir = substr($dir, 0, -1);
  70
  71         $allowed_dirs = $xc->getConf('allowed_dirs');
  72         $ok = false;
  73
  74         foreach ($allowed_dirs as $allowed_dir => $recursive) {
  75             $allowed_dir = $php->realpath($allowed_dir); // factor out!
  76             if (!is_string($allowed_dir)) continue;
  77             if ($dir === $allowed_dir) {
  78                 $ok = true;
  79                 break;
  80             // slash is required to prevent $allowed_dir = 'subdir' from
  81             // matching $dir = 'subdirectory', thanks Mordred!
  82             } elseif (strpos($dir, $allowed_dir . '/') === 0 && $recursive) {
  83                 $ok = true;
  84                 break;
  85             }
  86         }
  87
  88         if (!$ok) throw new XHTMLCompiler_Exception(403, 'Forbidden directory',
  89           'Requested directory is forbidden to XHTML Compiler; try
  90           accessing it directly or check for faulty <code>.htaccess</code> rules.');
  91
  92         // cannot use pathinfo, since PATHINFO_FILENAME is PHP 5.2.0
  93         $this->pathStem = substr($path, 0, strrpos($path, '.'));
  94
  95         // setup the files
  96         $this->source = new XHTMLCompiler_File($this->pathStem . '.' . $this->sourceExt);
  97         $this->cache  = new XHTMLCompiler_File($this->pathStem . '.' . $this->cacheExt);
  98         $this->deps   = new XHTMLCompiler_File($this->pathStem . '.' . $this->depsExt);
  99
 100         $this->dir    = new XHTMLCompiler_Directory(dirname($this->pathStem));
 101
 102         if (!$mute && !$this->source->exists()) {
 103             // Apache may have redirected to an ErrorDocument which got directed
 104             // via mod_rewrite to us, in that case, output the corresponding
 105             // status code.  Otherwise, we can give the regular 404.
 106             $code = $php->getRedirectStatus();
 107             if (!$code || $code == 200) $code = 404;
 108             throw new XHTMLCompiler_Exception($code, 'Page not found', 'Requested page not found; check the URL in your address bar.');
 109         }
 110     }
 111
 112     // Note: Do not use this functions internally inside the class
 113
 114     /** Returns path stem, full filename without file extension */
 115     public function getPathStem() { return $this->pathStem; }
 116     /** Returns relative path to cache */
 117     public function getCachePath() { return $this->cache->getName(); }
 118     /** Returns relative path to source */
 119     public function getSourcePath() { return $this->source->getName(); }
 120     /** Returns XHTMLCompiler_Directory representation of directory */
 121     public function getDir() { return $this->dir; }
 122     /** Returns directory of the files without trailing slash */
 123     public function getDirName() { return $this->dir->getName(); }
 124     /** Returns directory of the files with trailing slash (unless there is none) */
 125     public function getDirSName() { return $this->dir->getSName(); }
 126     /** Returns how deep from the root the file is */
 127     public function getDepth() { return substr_count($this->getSourcePath(), '/'); }
 128
 129     /** Normalizes a relative path as if it were from this page's directory */
 130     public function normalizePath($path) {
 131         return $this->getDirName() . '/' . $path;
 132     }
 133
 134     /**
 135      * Returns a fully formed web path to the file
 136      */
 137     public function getWebPath() {
 138         $xc = XHTMLCompiler::getInstance();
 139         $domain = $xc->getConf('web_domain');
 140         if (!$domain) {
 141             throw new Exception('Configuration value web_domain must be set for command line');
 142         }
 143         return 'http://' . $domain .
 144             $xc->getConf('web_path') . '/' . $this->cache->getName();
 145     }
 146
 147     /** Returns contents of the cache/served file */
 148     public function getCache() { return $this->cache->get(); }
 149     /** Returns contents of the source file */
 150     public function getSource() { return $this->source->get(); }
 151
 152     /** Reports whether or not cache file exists and is a file */
 153     public function isCacheExistent() { return $this->cache->exists(); }
 154     /** Reports whether or not source file exists and is a file */
 155     public function isSourceExistent() { return $this->source->exists(); }
 156
 157     /**
 158      * Reports whether or not the cache is stale by comparing the file
 159      * modification times between the source file and the cache file.
 160      * @warning You must not call this function until you've also called
 161      *          isCacheExistent().
 162      */
 163     public function isCacheStale() {
 164         if (!$this->cache->exists()) {
 165             throw new Exception('Cannot check for stale cache when cache
 166                 does not exist, please call isCacheExistent and take
 167                 appropriate action with the result');
 168         }
 169         if ($this->source->getMTime() > $this->cache->getMTime()) return true;
 170         // check dependencies
 171         if (!$this->deps->exists()) return true; // we need a dependency file!
 172         $deps = unserialize($this->deps->get());
 173         foreach ($deps as $filename => $time) {
 174             if ($time < filemtime($filename)) return true;
 175         }
 176         return false;
 177     }
 178
 179     /**
 180      * Writes text to the cache file, overwriting any previous contents
 181      * and creating the cache file if it doesn't exist.
 182      * @param $contents String contents to write to cache
 183      */
 184     public function writeCache($contents) {$this->cache->write($contents);}
 185
 186     /**
 187      * Attempts to display contents from the cache, otherwise returns false
 188      * @return True if successful, false if not.
 189      * @todo Purge check needs to be factored into XHTMLCompiler
 190      */
 191     public function tryCache() {
 192         if (
 193             !isset($_GET['purge']) &&
 194             $this->cache->exists() &&
 195             !$this->isCacheStale()
 196         ) {
 197             // cached version is fresh, serve it. This shouldn't happen normally
 198             set_response_code(200); // if we used ErrorDocument, override
 199             readfile($this->getCachePath());
 200             return true;
 201         }
 202         return false;
 203     }
 204
 205     /**
 206      * Generates the final version of a page from the source file and writes
 207      * it to the cache.
 208      * @note This function needs to be extended greatly
 209      * @return Generated contents from source
 210      */
 211     public function generate() {
 212         $source = $this->source->get();
 213         $xc = XHTMLCompiler::getInstance();
 214         $filters = $xc->getFilterManager();
 215         $contents = $filters->process($source, $this);
 216         $deps = $filters->getDeps();
 217         if (empty($contents)) return ''; // don't write, probably an error
 218         $contents .= '<!-- generated by XHTML Compiler -->';
 219         $this->cache->write($contents);
 220         $this->cache->chmod(0664);
 221         $this->deps->write(serialize($deps));
 222         return $contents;
 223     }
 224
 225     /**
 226      * Displays the page, either from cache or fresh regeneration.
 227      */
 228     public function display() {
 229         if($this->tryCache()) return;
 230         $ret = $this->generate();
 231         if ($ret) {
 232             if (stripos($_SERVER["HTTP_ACCEPT"], 'application/xhtml+xml') !== false) {
 233                 header("Content-type: application/xhtml+xml");
 234             } else {
 235                 header("Content-type: text/html");
 236             }
 237         }
 238         echo $ret;
 239     }
 240
 241     // Subversion related functions
 242
 243     protected $svnDate, $svnRevision, $svnAuthor, $svnHeadURL, $svnHeadURLMunged;
 244
 245     public function registerSVNKeywords(
 246         $date, $revision, $author, $head_url
 247     ) {
 248         $this->svnDate      = $date;
 249         $this->svnRevision  = (int) $revision;
 250         $this->svnAuthor    = $author;
 251         $this->svnHeadURL   = $head_url;
 252     }
 253     protected function loadSVNKeywords() {
 254         // this is an expensive function
 255         // we should log calls to it
 256         $raw_status = shell_exec('svn info "'.$this->getSourcePath().'"');
 257         if (!$raw_status) {
 258             throw new Exception('Attempt to grab SVN info for non-versioned file ' . $this->getCachePath());
 259         }
 260         $raw_status = str_replace("\r", '', $raw_status);
 261         $raw_status = explode("\n", $raw_status);
 262         $status = array();
 263         foreach ($raw_status as $i => $keyval) {
 264             if (empty($keyval)) continue;
 265             if (!strpos($keyval, ':')) continue;
 266             list($key, $value) = explode(': ', $keyval, 2);
 267             $status[$key] = $value;
 268         }
 269         $this->svnDate = $status['Last Changed Date'];
 270         $this->svnRevision = $status['Last Changed Rev'];
 271         $this->svnAuthor = $status['Last Changed Author'];
 272         $this->svnHeadURL = $status['URL'];
 273     }
 274     public function getSVNDate() {
 275         if (empty($this->svnDate)) $this->loadSVNKeywords();
 276         return $this->svnDate;
 277     }
 278     public function getSVNRevision() {
 279         if (empty($this->svnRevision)) $this->loadSVNKeywords();
 280         return $this->svnRevision;
 281     }
 282     public function getSVNAuthor() {
 283         if (empty($this->svnAuthor)) $this->loadSVNKeywords();
 284         return $this->svnAuthor;
 285     }
 286     /**
 287      * @warning The Head URL may not be publically accessible if
 288      *          svn+ssh:// or file:// protocols were used in the
 289      *          working copy.
 290      */
 291     public function getSVNHeadURL() {
 292         if (empty($this->svnHeadURL)) $this->loadSVNKeywords();
 293         return $this->svnHeadURL;
 294     }
 295
 296     /**
 297      * Returns the Head URL, but munged with svn_headurl_replace to
 298      * an accessible representation (see config.default.php for details)
 299      */
 300     public function getSVNHeadURLMunged() {
 301         if (!empty($this->svnHeadURLMunged)) return $this->svnHeadURLMunged;
 302         $head_url = $this->getSVNHeadURL();
 303         $xc = XHTMLCompiler::getInstance();
 304         $pairs = $xc->getConf('svn_headurl_munge');
 305         foreach ($pairs as $pair) {
 306             if (!(strpos($head_url, $pair[0]) === 0)) continue;
 307             $head_url = substr_replace($head_url, $pair[1], 0, strlen($pair[0]));
 308             break;
 309         }
 310         return $this->svnHeadURLMunged = $head_url;
 311     }
 312
 313 }
 314
 315 ?>