Add OpenGraph library - refs #5637

main/inc/lib/opengraph

@@ -1 +0,0 @@
-Subproject commit faba415deb9a84ae534dce78afdd5ca6535bdf12

main/inc/lib/opengraph/OpenGraph.php

@@ -0,0 +1,209 @@
+<?php
+/*
+  Copyright 2010 Scott MacVicar
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+
+*/
+
+class OpenGraph implements Iterator
+{
+  /**
+   * There are base schema's based on type, this is just
+   * a map so that the schema can be obtained
+   *
+   */
+    public static $TYPES = array(
+        'activity' => array('activity', 'sport'),
+        'business' => array('bar', 'company', 'cafe', 'hotel', 'restaurant'),
+        'group' => array('cause', 'sports_league', 'sports_team'),
+        'organization' => array('band', 'government', 'non_profit', 'school', 'university'),
+        'person' => array('actor', 'athlete', 'author', 'director', 'musician', 'politician', 'public_figure'),
+        'place' => array('city', 'country', 'landmark', 'state_province'),
+        'product' => array('album', 'book', 'drink', 'food', 'game', 'movie', 'product', 'song', 'tv_show'),
+        'website' => array('blog', 'website'),
+    );
+
+  /**
+   * Holds all the Open Graph values we've parsed from a page
+   *
+   */
+    private $_values = array();
+
+  /**
+   * Fetches a URI and parses it for Open Graph data, returns
+   * false on error.
+   *
+   * @param $URI    URI to page to parse for Open Graph data
+   * @return OpenGraph
+   */
+    static public function fetch($URI) {
+        $curl = curl_init($URI);
+
+        curl_setopt($curl, CURLOPT_FAILONERROR, true);
+        curl_setopt($curl, CURLOPT_FOLLOWLOCATION, true);
+        curl_setopt($curl, CURLOPT_RETURNTRANSFER, true);
+        curl_setopt($curl, CURLOPT_TIMEOUT, 15);
+        curl_setopt($curl, CURLOPT_SSL_VERIFYHOST, false);
+        curl_setopt($curl, CURLOPT_SSL_VERIFYPEER, false);
+        curl_setopt($curl, CURLOPT_USERAGENT, $_SERVER['HTTP_USER_AGENT']);
+
+        $response = curl_exec($curl);
+
+        curl_close($curl);
+
+        if (!empty($response)) {
+            return self::_parse($response);
+        } else {
+            return false;
+        }
+    }
+
+  /**
+   * Parses HTML and extracts Open Graph data, this assumes
+   * the document is at least well formed.
+   *
+   * @param $HTML    HTML to parse
+   * @return OpenGraph
+   */
+    static private function _parse($HTML) {
+        $old_libxml_error = libxml_use_internal_errors(true);
+
+        $doc = new DOMDocument();
+        $doc->loadHTML($HTML);
+
+        libxml_use_internal_errors($old_libxml_error);
+
+        $tags = $doc->getElementsByTagName('meta');
+        if (!$tags || $tags->length === 0) {
+            return false;
+        }
+
+        $page = new self();
+
+        $nonOgDescription = null;
+
+        foreach ($tags AS $tag) {
+            if ($tag->hasAttribute('property') &&
+                strpos($tag->getAttribute('property'), 'og:') === 0) {
+                $key = strtr(substr($tag->getAttribute('property'), 3), '-', '_');
+                $page->_values[$key] = $tag->getAttribute('content');
+            }
+
+            //Added this if loop to retrieve description values from sites like the New York Times who have malformed it.
+            if ($tag ->hasAttribute('value') && $tag->hasAttribute('property') &&
+                strpos($tag->getAttribute('property'), 'og:') === 0) {
+                $key = strtr(substr($tag->getAttribute('property'), 3), '-', '_');
+                $page->_values[$key] = $tag->getAttribute('value');
+            }
+            if ($tag->hasAttribute('name') && $tag->getAttribute('name') === 'description') {
+                $nonOgDescription = $tag->getAttribute('content');
+            }
+
+        }
+        if (!isset($page->_values['title'])) {
+            $titles = $doc->getElementsByTagName('title');
+            if ($titles->length > 0) {
+                $page->_values['title'] = $titles->item(0)->textContent;
+            }
+        }
+        if (!isset($page->_values['description']) && $nonOgDescription) {
+            $page->_values['description'] = $nonOgDescription;
+        }
+
+        //Fallback to use image_src if ogp::image isn't set.
+        if (!isset($page->values['image'])) {
+            $domxpath = new DOMXPath($doc);
+            $elements = $domxpath->query("//link[@rel='image_src']");
+
+            if ($elements->length > 0) {
+                $domattr = $elements->item(0)->attributes->getNamedItem('href');
+                if ($domattr) {
+                    $page->_values['image'] = $domattr->value;
+                    $page->_values['image_src'] = $domattr->value;
+                }
+            }
+        }
+
+        if (empty($page->_values)) { return false; }
+
+        return $page;
+    }
+
+  /**
+   * Helper method to access attributes directly
+   * Example:
+   * $graph->title
+   *
+   * @param $key    Key to fetch from the lookup
+   */
+    public function __get($key) {
+        if (array_key_exists($key, $this->_values)) {
+            return $this->_values[$key];
+        }
+
+        if ($key === 'schema') {
+            foreach (self::$TYPES AS $schema => $types) {
+                if (array_search($this->_values['type'], $types)) {
+                    return $schema;
+                }
+            }
+        }
+    }
+
+  /**
+   * Return all the keys found on the page
+   *
+   * @return array
+   */
+    public function keys() {
+        return array_keys($this->_values);
+    }
+
+  /**
+   * Helper method to check an attribute exists
+   *
+   * @param $key
+   */
+    public function __isset($key) {
+        return array_key_exists($key, $this->_values);
+    }
+
+  /**
+   * Will return true if the page has location data embedded
+   *
+   * @return boolean Check if the page has location data
+   */
+    public function hasLocation() {
+        if (array_key_exists('latitude', $this->_values) && array_key_exists('longitude', $this->_values)) {
+            return true;
+        }
+
+        $address_keys = array('street_address', 'locality', 'region', 'postal_code', 'country_name');
+        $valid_address = true;
+        foreach ($address_keys AS $key) {
+            $valid_address = ($valid_address && array_key_exists($key, $this->_values));
+        }
+        return $valid_address;
+    }
+
+  /**
+   * Iterator code
+   */
+    private $_position = 0;
+    public function rewind() { reset($this->_values); $this->_position = 0; }
+    public function current() { return current($this->_values); }
+    public function key() { return key($this->_values); }
+    public function next() { next($this->_values); ++$this->_position; }
+    public function valid() { return $this->_position < sizeof($this->_values); }
+}