application/FeedBuilder.php

   1 <?php
   2
   3 /**
   4  * FeedBuilder class.
   5  *
   6  * Used to build ATOM and RSS feeds data.
   7  */
   8 class FeedBuilder
   9 {
  10     /**
  11      * @var string Constant: RSS feed type.
  12      */
  13     public static $FEED_RSS = 'rss';
  14
  15     /**
  16      * @var string Constant: ATOM feed type.
  17      */
  18     public static $FEED_ATOM = 'atom';
  19
  20     /**
  21      * @var string Default language if the locale isn't set.
  22      */
  23     public static $DEFAULT_LANGUAGE = 'en-en';
  24
  25     /**
  26      * @var int Number of links to display in a feed by default.
  27      */
  28     public static $DEFAULT_NB_LINKS = 50;
  29
  30     /**
  31      * @var LinkDB instance.
  32      */
  33     protected $linkDB;
  34
  35     /**
  36      * @var string RSS or ATOM feed.
  37      */
  38     protected $feedType;
  39
  40     /**
  41      * @var array $_SERVER.
  42      */
  43     protected $serverInfo;
  44
  45     /**
  46      * @var array $_GET.
  47      */
  48     protected $userInput;
  49
  50     /**
  51      * @var boolean True if the user is currently logged in, false otherwise.
  52      */
  53     protected $isLoggedIn;
  54
  55     /**
  56      * @var boolean Use permalinks instead of direct links if true.
  57      */
  58     protected $usePermalinks;
  59
  60     /**
  61      * @var boolean true to hide dates in feeds.
  62      */
  63     protected $hideDates;
  64
  65     /**
  66      * @var string PubSub hub URL.
  67      */
  68     protected $pubsubhubUrl;
  69
  70     /**
  71      * @var string server locale.
  72      */
  73     protected $locale;
  74
  75     /**
  76      * @var DateTime Latest item date.
  77      */
  78     protected $latestDate;
  79
  80     /**
  81      * Feed constructor.
  82      *
  83      * @param LinkDB  $linkDB        LinkDB instance.
  84      * @param string  $feedType      Type of feed.
  85      * @param array   $serverInfo    $_SERVER.
  86      * @param array   $userInput     $_GET.
  87      * @param boolean $isLoggedIn True if the user is currently logged in, false otherwise.
  88      */
  89     public function __construct($linkDB, $feedType, $serverInfo, $userInput, $isLoggedIn)
  90     {
  91         $this->linkDB = $linkDB;
  92         $this->feedType = $feedType;
  93         $this->serverInfo = $serverInfo;
  94         $this->userInput = $userInput;
  95         $this->isLoggedIn = $isLoggedIn;
  96     }
  97
  98     /**
  99      * Build data for feed templates.
 100      *
 101      * @return array Formatted data for feeds templates.
 102      */
 103     public function buildData()
 104     {
 105         // Optionally filter the results:
 106         $searchtags = !empty($this->userInput['searchtags']) ? escape($this->userInput['searchtags']) : '';
 107         $searchterm = !empty($this->userInput['searchterm']) ? escape($this->userInput['searchterm']) : '';
 108         if (! empty($searchtags) && ! empty($searchterm)) {
 109             $linksToDisplay = $this->linkDB->filter(
 110                 LinkFilter::$FILTER_TAG | LinkFilter::$FILTER_TEXT,
 111                 array($searchtags, $searchterm)
 112             );
 113         }
 114         elseif ($searchtags) {
 115             $linksToDisplay = $this->linkDB->filter(LinkFilter::$FILTER_TAG, $searchtags);
 116         }
 117         elseif ($searchterm) {
 118             $linksToDisplay = $this->linkDB->filter(LinkFilter::$FILTER_TEXT, $searchterm);
 119         }
 120         else {
 121             $linksToDisplay = $this->linkDB;
 122         }
 123
 124         $nblinksToDisplay = $this->getNbLinks(count($linksToDisplay));
 125
 126         // Can't use array_keys() because $link is a LinkDB instance and not a real array.
 127         $keys = array();
 128         foreach ($linksToDisplay as $key => $value) {
 129             $keys[] = $key;
 130         }
 131
 132         $pageaddr = escape(index_url($this->serverInfo));
 133         $linkDisplayed = array();
 134         for ($i = 0; $i < $nblinksToDisplay && $i < count($keys); $i++) {
 135             $linkDisplayed[$keys[$i]] = $this->buildItem($linksToDisplay[$keys[$i]], $pageaddr);
 136         }
 137
 138         $data['language'] = $this->getTypeLanguage();
 139         $data['pubsubhub_url'] = $this->pubsubhubUrl;
 140         $data['last_update'] = $this->getLatestDateFormatted();
 141         $data['show_dates'] = !$this->hideDates || $this->isLoggedIn;
 142         // Remove leading slash from REQUEST_URI.
 143         $data['self_link'] = $pageaddr . escape(ltrim($this->serverInfo['REQUEST_URI'], '/'));
 144         $data['index_url'] = $pageaddr;
 145         $data['usepermalinks'] = $this->usePermalinks === true;
 146         $data['links'] = $linkDisplayed;
 147
 148         return $data;
 149     }
 150
 151     /**
 152      * Build a feed item (one per shaare).
 153      *
 154      * @param array  $link     Single link array extracted from LinkDB.
 155      * @param string $pageaddr Index URL.
 156      *
 157      * @return array Link array with feed attributes.
 158      */
 159     protected function buildItem($link, $pageaddr)
 160     {
 161         $link['guid'] = $pageaddr .'?'. smallHash($link['linkdate']);
 162         // Check for both signs of a note: starting with ? and 7 chars long.
 163         if ($link['url'][0] === '?' && strlen($link['url']) === 7) {
 164             $link['url'] = $pageaddr . $link['url'];
 165         }
 166         if ($this->usePermalinks === true) {
 167             $permalink = '<a href="'. $link['url'] .'" title="Direct link">Direct link</a>';
 168         } else {
 169             $permalink = '<a href="'. $link['guid'] .'" title="Permalink">Permalink</a>';
 170         }
 171         $link['description'] = format_description($link['description']) . PHP_EOL .'<br>&#8212; '. $permalink;
 172
 173         $date = DateTime::createFromFormat(LinkDB::LINK_DATE_FORMAT, $link['linkdate']);
 174
 175         if ($this->feedType == self::$FEED_RSS) {
 176             $link['iso_date'] = $date->format(DateTime::RSS);
 177         } else {
 178             $link['iso_date'] = $date->format(DateTime::ATOM);
 179         }
 180
 181         // Save the more recent item.
 182         if (empty($this->latestDate) || $this->latestDate < $date) {
 183             $this->latestDate = $date;
 184         }
 185
 186         $taglist = array_filter(explode(' ', $link['tags']), 'strlen');
 187         uasort($taglist, 'strcasecmp');
 188         $link['taglist'] = $taglist;
 189
 190         return $link;
 191     }
 192
 193     /**
 194      * Assign PubSub hub URL.
 195      *
 196      * @param string $pubsubhubUrl PubSub hub url.
 197      */
 198     public function setPubsubhubUrl($pubsubhubUrl)
 199     {
 200         $this->pubsubhubUrl = $pubsubhubUrl;
 201     }
 202
 203     /**
 204      * Set this to true to use permalinks instead of direct links.
 205      *
 206      * @param boolean $usePermalinks true to force permalinks.
 207      */
 208     public function setUsePermalinks($usePermalinks)
 209     {
 210         $this->usePermalinks = $usePermalinks;
 211     }
 212
 213     /**
 214      * Set this to true to hide timestamps in feeds.
 215      *
 216      * @param boolean $hideDates true to enable.
 217      */
 218     public function setHideDates($hideDates)
 219     {
 220         $this->hideDates = $hideDates;
 221     }
 222
 223     /**
 224      * Set the locale. Used to show feed language.
 225      *
 226      * @param string $locale The locale (eg. 'fr_FR.UTF8').
 227      */
 228     public function setLocale($locale)
 229     {
 230         $this->locale = strtolower($locale);
 231     }
 232
 233     /**
 234      * Get the language according to the feed type, based on the locale:
 235      *
 236      *   - RSS format: en-us (default: 'en-en').
 237      *   - ATOM format: fr (default: 'en').
 238      *
 239      * @return string The language.
 240      */
 241     public function getTypeLanguage()
 242     {
 243         // Use the locale do define the language, if available.
 244         if (! empty($this->locale) && preg_match('/^\w{2}[_\-]\w{2}/', $this->locale)) {
 245             $length = ($this->feedType == self::$FEED_RSS) ? 5 : 2;
 246             return str_replace('_', '-', substr($this->locale, 0, $length));
 247         }
 248         return ($this->feedType == self::$FEED_RSS) ? 'en-en' : 'en';
 249     }
 250
 251     /**
 252      * Format the latest item date found according to the feed type.
 253      *
 254      * Return an empty string if invalid DateTime is passed.
 255      *
 256      * @return string Formatted date.
 257      */
 258     protected function getLatestDateFormatted()
 259     {
 260         if (empty($this->latestDate) || !$this->latestDate instanceof DateTime) {
 261             return '';
 262         }
 263
 264         $type = ($this->feedType == self::$FEED_RSS) ? DateTime::RSS : DateTime::ATOM;
 265         return $this->latestDate->format($type);
 266     }
 267
 268     /**
 269      * Returns the number of link to display according to 'nb' user input parameter.
 270      *
 271      * If 'nb' not set or invalid, default value: $DEFAULT_NB_LINKS.
 272      * If 'nb' is set to 'all', display all filtered links (max parameter).
 273      *
 274      * @param int $max maximum number of links to display.
 275      *
 276      * @return int number of links to display.
 277      */
 278     public function getNbLinks($max)
 279     {
 280         if (empty($this->userInput['nb'])) {
 281             return self::$DEFAULT_NB_LINKS;
 282         }
 283
 284         if ($this->userInput['nb'] == 'all') {
 285             return $max;
 286         }
 287
 288         $intNb = intval($this->userInput['nb']);
 289         if (! is_int($intNb) || $intNb == 0) {
 290             return self::$DEFAULT_NB_LINKS;
 291         }
 292
 293         return $intNb;
 294     }
 295 }