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         $linksToDisplay = $this->linkDB->filterSearch($this->userInput);
 107
 108         $nblinksToDisplay = $this->getNbLinks(count($linksToDisplay));
 109
 110         // Can't use array_keys() because $link is a LinkDB instance and not a real array.
 111         $keys = array();
 112         foreach ($linksToDisplay as $key => $value) {
 113             $keys[] = $key;
 114         }
 115
 116         $pageaddr = escape(index_url($this->serverInfo));
 117         $linkDisplayed = array();
 118         for ($i = 0; $i < $nblinksToDisplay && $i < count($keys); $i++) {
 119             $linkDisplayed[$keys[$i]] = $this->buildItem($linksToDisplay[$keys[$i]], $pageaddr);
 120         }
 121
 122         $data['language'] = $this->getTypeLanguage();
 123         $data['pubsubhub_url'] = $this->pubsubhubUrl;
 124         $data['last_update'] = $this->getLatestDateFormatted();
 125         $data['show_dates'] = !$this->hideDates || $this->isLoggedIn;
 126         // Remove leading slash from REQUEST_URI.
 127         $data['self_link'] = $pageaddr . escape(ltrim($this->serverInfo['REQUEST_URI'], '/'));
 128         $data['index_url'] = $pageaddr;
 129         $data['usepermalinks'] = $this->usePermalinks === true;
 130         $data['links'] = $linkDisplayed;
 131
 132         return $data;
 133     }
 134
 135     /**
 136      * Build a feed item (one per shaare).
 137      *
 138      * @param array  $link     Single link array extracted from LinkDB.
 139      * @param string $pageaddr Index URL.
 140      *
 141      * @return array Link array with feed attributes.
 142      */
 143     protected function buildItem($link, $pageaddr)
 144     {
 145         $link['guid'] = $pageaddr .'?'. smallHash($link['linkdate']);
 146         // Check for both signs of a note: starting with ? and 7 chars long.
 147         if ($link['url'][0] === '?' && strlen($link['url']) === 7) {
 148             $link['url'] = $pageaddr . $link['url'];
 149         }
 150         if ($this->usePermalinks === true) {
 151             $permalink = '<a href="'. $link['url'] .'" title="Direct link">Direct link</a>';
 152         } else {
 153             $permalink = '<a href="'. $link['guid'] .'" title="Permalink">Permalink</a>';
 154         }
 155         $link['description'] = format_description($link['description']) . PHP_EOL .'<br>&#8212; '. $permalink;
 156
 157         $pubDate = DateTime::createFromFormat(LinkDB::LINK_DATE_FORMAT, $link['linkdate']);
 158         $link['pub_iso_date'] = $this->getIsoDate($pubDate);
 159
 160         // atom:entry elements MUST contain exactly one atom:updated element.
 161         if (!empty($link['updated'])) {
 162             $upDate = DateTime::createFromFormat(LinkDB::LINK_DATE_FORMAT, $link['updated']);
 163             $link['up_iso_date'] = $this->getIsoDate($upDate, DateTime::ATOM);
 164         } else {
 165             $link['up_iso_date'] = $this->getIsoDate($pubDate, DateTime::ATOM);;
 166         }
 167
 168         // Save the more recent item.
 169         if (empty($this->latestDate) || $this->latestDate < $pubDate) {
 170             $this->latestDate = $pubDate;
 171         }
 172         if (!empty($upDate) && $this->latestDate < $upDate) {
 173             $this->latestDate = $upDate;
 174         }
 175
 176         $taglist = array_filter(explode(' ', $link['tags']), 'strlen');
 177         uasort($taglist, 'strcasecmp');
 178         $link['taglist'] = $taglist;
 179
 180         return $link;
 181     }
 182
 183     /**
 184      * Assign PubSub hub URL.
 185      *
 186      * @param string $pubsubhubUrl PubSub hub url.
 187      */
 188     public function setPubsubhubUrl($pubsubhubUrl)
 189     {
 190         $this->pubsubhubUrl = $pubsubhubUrl;
 191     }
 192
 193     /**
 194      * Set this to true to use permalinks instead of direct links.
 195      *
 196      * @param boolean $usePermalinks true to force permalinks.
 197      */
 198     public function setUsePermalinks($usePermalinks)
 199     {
 200         $this->usePermalinks = $usePermalinks;
 201     }
 202
 203     /**
 204      * Set this to true to hide timestamps in feeds.
 205      *
 206      * @param boolean $hideDates true to enable.
 207      */
 208     public function setHideDates($hideDates)
 209     {
 210         $this->hideDates = $hideDates;
 211     }
 212
 213     /**
 214      * Set the locale. Used to show feed language.
 215      *
 216      * @param string $locale The locale (eg. 'fr_FR.UTF8').
 217      */
 218     public function setLocale($locale)
 219     {
 220         $this->locale = strtolower($locale);
 221     }
 222
 223     /**
 224      * Get the language according to the feed type, based on the locale:
 225      *
 226      *   - RSS format: en-us (default: 'en-en').
 227      *   - ATOM format: fr (default: 'en').
 228      *
 229      * @return string The language.
 230      */
 231     public function getTypeLanguage()
 232     {
 233         // Use the locale do define the language, if available.
 234         if (! empty($this->locale) && preg_match('/^\w{2}[_\-]\w{2}/', $this->locale)) {
 235             $length = ($this->feedType == self::$FEED_RSS) ? 5 : 2;
 236             return str_replace('_', '-', substr($this->locale, 0, $length));
 237         }
 238         return ($this->feedType == self::$FEED_RSS) ? 'en-en' : 'en';
 239     }
 240
 241     /**
 242      * Format the latest item date found according to the feed type.
 243      *
 244      * Return an empty string if invalid DateTime is passed.
 245      *
 246      * @return string Formatted date.
 247      */
 248     protected function getLatestDateFormatted()
 249     {
 250         if (empty($this->latestDate) || !$this->latestDate instanceof DateTime) {
 251             return '';
 252         }
 253
 254         $type = ($this->feedType == self::$FEED_RSS) ? DateTime::RSS : DateTime::ATOM;
 255         return $this->latestDate->format($type);
 256     }
 257
 258     /**
 259      * Get ISO date from DateTime according to feed type.
 260      *
 261      * @param DateTime    $date   Date to format.
 262      * @param string|bool $format Force format.
 263      *
 264      * @return string Formatted date.
 265      */
 266     protected function getIsoDate(DateTime $date, $format = false)
 267     {
 268         if ($format !== false) {
 269             return $date->format($format);
 270         }
 271         if ($this->feedType == self::$FEED_RSS) {
 272             return $date->format(DateTime::RSS);
 273
 274         }
 275         return $date->format(DateTime::ATOM);
 276     }
 277
 278     /**
 279      * Returns the number of link to display according to 'nb' user input parameter.
 280      *
 281      * If 'nb' not set or invalid, default value: $DEFAULT_NB_LINKS.
 282      * If 'nb' is set to 'all', display all filtered links (max parameter).
 283      *
 284      * @param int $max maximum number of links to display.
 285      *
 286      * @return int number of links to display.
 287      */
 288     public function getNbLinks($max)
 289     {
 290         if (empty($this->userInput['nb'])) {
 291             return self::$DEFAULT_NB_LINKS;
 292         }
 293
 294         if ($this->userInput['nb'] == 'all') {
 295             return $max;
 296         }
 297
 298         $intNb = intval($this->userInput['nb']);
 299         if (! is_int($intNb) || $intNb == 0) {
 300             return self::$DEFAULT_NB_LINKS;
 301         }
 302
 303         return $intNb;
 304     }
 305 }