* * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program. If not, see . */ require_once 'Symfony/Component/Serializer/autoload.php'; use Symfony\Component\Serializer\Serializer; use Symfony\Component\Serializer\Encoder\XmlEncoder; use Symfony\Component\Serializer\Normalizer\ObjectNormalizer; date_default_timezone_set('UTC'); /** * Scrape supported websites and perform conversion to RSS. */ class Tweeper { private static $userAgent = "Mozilla/5.0 (Windows NT 6.1; rv:22.0) Gecko/20130405 Firefox/22.0"; /** * Constructor sets up {@link $generate_enclosure}. */ public function __construct($generate_enclosure = FALSE) { $this->generate_enclosure = $generate_enclosure; } /** * Convert numeric Epoch to the date format expected in a RSS document. */ public static function epochToRssDate($timestamp) { if (!is_numeric($timestamp) || is_nan($timestamp)) { $timestamp = 0; } return gmdate(DATE_RSS, $timestamp); } /** * Convert generic date string to the date format expected in a RSS document. */ public static function strToRssDate($date) { $timestamp = strtotime($date); if (FALSE === $timestamp) { $timestamp = 0; } return Tweeper::epochToRssDate($timestamp); } /** * Convert string to UpperCamelCase. */ public static function toUpperCamelCase($str, $delim = ' ') { $str_upper = ucwords($str, $delim); $str_camel_case = str_replace($delim, '', $str_upper); return $str_camel_case; } /** * Get the contents from a URL. */ private static function getUrlContents($url) { $ch = curl_init($url); curl_setopt_array($ch, array( CURLOPT_HEADER => FALSE, // Follow http redirects to get the real URL. CURLOPT_FOLLOWLOCATION => TRUE, CURLOPT_RETURNTRANSFER => TRUE, CURLOPT_SSL_VERIFYHOST => FALSE, CURLOPT_SSL_VERIFYPEER => FALSE, CURLOPT_HTTPHEADER => array('Accept-language: en'), CURLOPT_USERAGENT => Tweeper::$userAgent, )); $contents = curl_exec($ch); curl_close($ch); return $contents; } /** * Get the headers from a URL. */ private static function getUrlInfo($url) { $ch = curl_init($url); curl_setopt_array($ch, array( CURLOPT_HEADER => TRUE, CURLOPT_NOBODY => TRUE, // Follow http redirects to get the real URL. CURLOPT_FOLLOWLOCATION => TRUE, CURLOPT_RETURNTRANSFER => TRUE, CURLOPT_SSL_VERIFYHOST => FALSE, CURLOPT_SSL_VERIFYPEER => FALSE, CURLOPT_USERAGENT => Tweeper::$userAgent, )); curl_exec($ch); $url_info = curl_getinfo($ch); curl_close($ch); return $url_info; } /** * Generate an RSS element. */ public static function generateEnclosure($url) { $supported_content_types = array( "application/octet-stream", "application/ogg", "application/pdf", "audio/aac", "audio/mp4", "audio/mpeg", "audio/ogg", "audio/vorbis", "audio/wav", "audio/webm", "audio/x-midi", "image/gif", "image/jpeg", "image/png", "video/avi", "video/mp4", "video/mpeg", "video/ogg", ); $url_info = Tweeper::getUrlInfo($url); $supported = in_array($url_info['content_type'], $supported_content_types); if (!$supported) { error_log("Unsupported enclosure content type \"" . $url_info['content_type'] . "\" for URL: " . $url_info['url']); return ''; } // The RSS specification says that the enclosure element URL must be http. // See http://sourceforge.net/p/feedvalidator/bugs/72/ $http_url = preg_replace("/^https/", "http", $url_info['url']); $dom = new DOMDocument(); $enc = $dom->createElement('enclosure'); $enc->setAttribute('url', $http_url); $enc->setAttribute('length', $url_info['download_content_length']); $enc->setAttribute('type', $url_info['content_type']); return $enc; } /** * Mimic the message from libxml.c::php_libxml_ctx_error_level() */ private static function logXmlError($error) { $output = ""; switch ($error->level) { case LIBXML_ERR_WARNING: $output .= "Warning $error->code: "; break; case LIBXML_ERR_ERROR: $output .= "Error $error->code: "; break; case LIBXML_ERR_FATAL: $output .= "Fatal Error $error->code: "; break; } $output .= trim($error->message); if ($error->file) { $output .= " in $error->file"; } else { $output .= " in Entity,"; } $output .= " line $error->line"; error_log($output); } /** * Convert json to XML. */ private static function jsonToXml($json, $root_node_name) { // Apparently the ObjectNormalizer used afterwards is not able to handle // the stdClass object created by json_decode() with the default setting // $assoc = false; so use $assoc = true. $data = json_decode($json, $assoc = TRUE); if (!$data) { return NULL; } $encoder = new XmlEncoder(); $normalizer = new ObjectNormalizer(); $serializer = new Serializer(array($normalizer), array($encoder)); $serializer_options = array( 'xml_encoding' => "UTF-8", 'xml_format_output' => TRUE, 'xml_root_node_name' => $root_node_name, ); $xml_data = $serializer->serialize($data, 'xml', $serializer_options); if (!$xml_data) { trigger_error("Cannot serialize data", E_USER_ERROR); return NULL; } return $xml_data; } /** * Convert the Instagram content to XML. */ private function getXmlInstagramCom($html) { // Extract the json data from the html code. $json_match_expr = '/window._sharedData = (.*);/'; $ret = preg_match($json_match_expr, $html, $matches); if ($ret !== 1) { trigger_error("Cannot match expression: $json_match_expr\n", E_USER_ERROR); return NULL; } return Tweeper::jsonToXml($matches[1], 'instagram'); } /** * Make the Facebook HTML processable. */ private function preprocessHtmlFacebookCom($html) { $html = str_replace('', '', $html); return $html; } /** * Convert the HTML retrieved from the site to XML. */ private function htmlToXml($html, $host) { $xmlDoc = new DOMDocument(); // Handle warnings and errors when loading invalid HTML. $xml_errors_value = libxml_use_internal_errors(TRUE); // If there is a host-specific method to get the XML data, use it! $get_xml_host_method = 'getXml' . Tweeper::toUpperCamelCase($host, '.'); if (method_exists($this, $get_xml_host_method)) { $xml_data = call_user_func_array(array($this, $get_xml_host_method), array($html)); $xmlDoc->loadXML($xml_data); } else { $xmlDoc->loadHTML($html); } foreach (libxml_get_errors() as $xml_error) { Tweeper::logXmlError($xml_error); } libxml_clear_errors(); libxml_use_internal_errors($xml_errors_value); return $xmlDoc; } /** * Load a stylesheet if the web site is supported. */ private function loadStylesheet($host) { $stylesheet = "file://" . __DIR__ . "/rss_converter_" . $host . ".xsl"; if (FALSE === file_exists($stylesheet)) { trigger_error("Conversion to RSS not supported for $host ($stylesheet not found)", E_USER_ERROR); return NULL; } $stylesheet_contents = Tweeper::getUrlContents($stylesheet); $xslDoc = new DOMDocument(); $xslDoc->loadXML($stylesheet_contents); $xsltProcessor = new XSLTProcessor(); $xsltProcessor->registerPHPFunctions(); $xsltProcessor->setParameter('', 'generate-enclosure', $this->generate_enclosure); $xsltProcessor->importStylesheet($xslDoc); return $xsltProcessor; } /** * Convert the site content to RSS. */ public function tweep($src_url) { $url = parse_url($src_url); if (FALSE === $url || empty($url["host"])) { trigger_error("Invalid URL: $src_url", E_USER_ERROR); return NULL; } // Strip the leading www. to be more forgiving on input URLs. $host = preg_replace('/^www\./', '', $url["host"]); $xsltProcessor = $this->loadStylesheet($host); if (NULL === $xsltProcessor) { return NULL; } $html = Tweeper::getUrlContents($src_url); if (FALSE === $html) { return NULL; } $preprocess_html_host_method = 'preprocessHtml' . Tweeper::toUpperCamelCase($host, '.'); if (method_exists($this, $preprocess_html_host_method)) { $html = call_user_func_array(array($this, $preprocess_html_host_method), array($html)); } $xmlDoc = $this->htmlToXml($html, $host); if (NULL === $xmlDoc) { return NULL; } $output = $xsltProcessor->transformToXML($xmlDoc); if (FALSE === $output) { trigger_error('XSL transformation failed.', E_USER_ERROR); return NULL; } return $output; } } /** * Check if the script is being run from the command line. */ function is_cli() { return (php_sapi_name() === "cli"); } /** * Show the script usage. */ function usage($argv) { if (is_cli()) { $usage = "{$argv[0]} [-e|-h|--help] \n"; } else { $usage = htmlentities("{$_SERVER['SCRIPT_NAME']}?src_url=&generate_enclosure=<0|1>"); } return "usage: $usage"; } /** * Parse command line options. */ function parse_options_cli($argv, $argc) { $options = array( 'generate_enclosure' => FALSE, ); if ($argc < 2) { return $options; } $cli_options = getopt("eh", array("help")); foreach ($cli_options as $opt => $val) { switch ($opt) { case 'e': $options['generate_enclosure'] = TRUE; break; case 'h': case 'help': echo usage($argv); exit(0); default: fwrite(STDERR, usage($argv)); exit(1); } } $options['src_url'] = $argv[count($cli_options) + 1]; return $options; } /** * Parse options passed from a query string. */ function parse_options_query_string() { $options = array( 'generate_enclosure' => FALSE, ); if (isset($_GET['src_url'])) { $options['src_url'] = $_GET['src_url']; } if (isset($_GET['generate_enclosure'])) { $options['generate_enclosure'] = $_GET['generate_enclosure'] == 1; } return $options; } if (is_cli()) { $options = parse_options_cli($argv, $argc); $error_stream = fopen('php://stderr', 'w'); } else { $options = parse_options_query_string(); $error_stream = fopen('php://output', 'w'); } if (!isset($options['src_url'])) { fwrite($error_stream, usage(is_cli() ? $argv : NULL)); exit(1); } $tweeper = new Tweeper($options['generate_enclosure']); echo $tweeper->tweep($options['src_url']);