* @file
* Tweeper - a Twitter to RSS web scraper.
*
- * Copyright (C) 2013-2018 Antonio Ospite <ao2@ao2.it>
+ * Copyright (C) 2013-2020 Antonio Ospite <ao2@ao2.it>
*
* 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
*/
class Tweeper {
- private static $userAgent = "Mozilla/5.0 (Windows NT 6.1; WOW64; rv:60.0) Gecko/20100101 Firefox/60.0";
+ private static $userAgent = "APIs-Google (+https://developers.google.com/webmasters/APIs-Google.html)";
+ private static $maxConnectionTimeout = 5;
+ private static $maxConnectionRetries = 5;
/**
- * Constructor sets up {@link $generate_enclosure}.
+ * Create a new Tweeper object controlling optional settings.
+ *
+ * @param bool $generate_enclosure
+ * Enables the creation of <enclosure/> elements (disabled by default).
+ * @param bool $show_usernames
+ * Enables showing the username in front of the content for multi-user
+ * sites (enabled by default). Only some stylesheets supports this
+ * functionality (twitter, instagram, pump.io).
+ * @param bool $show_multimedia
+ * Enables showing multimedia content (images, videos) directly in the
+ * item description (enabled by default). Only some stylesheets supports
+ * this functionality (twitter, instagram, dilbert).
+ * @param bool $verbose_output
+ * Enables showing non-fatal errors like XML parsing errors.
*/
- public function __construct($generate_enclosure = FALSE) {
+ public function __construct($generate_enclosure = FALSE, $show_usernames = TRUE, $show_multimedia = TRUE, $verbose_output = TRUE) {
$this->generate_enclosure = $generate_enclosure;
+ $this->show_usernames = $show_usernames;
+ $this->show_multimedia = $show_multimedia;
+ $this->verbose_output = $verbose_output;
}
/**
}
/**
+ * Perform a cURL session multiple times when it fails with a timeout.
+ *
+ * @param resource $ch
+ * a cURL session handle.
+ */
+ private static function curlExec($ch) {
+ $ret = FALSE;
+ $attempt = 0;
+ do {
+ $ret = curl_exec($ch);
+ if (FALSE === $ret) {
+ trigger_error(curl_error($ch), E_USER_WARNING);
+ }
+ } while (curl_errno($ch) == CURLE_OPERATION_TIMEDOUT && ++$attempt < Tweeper::$maxConnectionRetries);
+
+ return $ret;
+ }
+
+ /**
* Get the contents from a URL.
*/
- private static function getUrlContents($url) {
+ private static function getUrlContents($url, $user_agent = NULL) {
$ch = curl_init($url);
- curl_setopt_array($ch, array(
+ curl_setopt_array($ch, [
CURLOPT_HEADER => FALSE,
+ CURLOPT_CONNECTTIMEOUT => Tweeper::$maxConnectionTimeout,
// Follow http redirects to get the real URL.
CURLOPT_FOLLOWLOCATION => TRUE,
+ CURLOPT_COOKIEFILE => "",
CURLOPT_RETURNTRANSFER => TRUE,
- CURLOPT_SSL_VERIFYHOST => FALSE,
- CURLOPT_SSL_VERIFYPEER => FALSE,
- CURLOPT_HTTPHEADER => array('Accept-language: en'),
- CURLOPT_USERAGENT => Tweeper::$userAgent,
- ));
- $contents = curl_exec($ch);
- if (FALSE === $contents) {
- trigger_error(curl_error($ch));
- }
+ CURLOPT_HTTPHEADER => ['Accept-language: en'],
+ CURLOPT_USERAGENT => isset($user_agent) ? $user_agent : Tweeper::$userAgent,
+ ]);
+ $contents = Tweeper::curlExec($ch);
curl_close($ch);
return $contents;
/**
* Get the headers from a URL.
*/
- private static function getUrlInfo($url) {
+ private static function getUrlInfo($url, $user_agent = NULL) {
$ch = curl_init($url);
- curl_setopt_array($ch, array(
+ curl_setopt_array($ch, [
CURLOPT_HEADER => TRUE,
CURLOPT_NOBODY => TRUE,
+ CURLOPT_CONNECTTIMEOUT => Tweeper::$maxConnectionTimeout,
// Follow http redirects to get the real URL.
CURLOPT_FOLLOWLOCATION => TRUE,
CURLOPT_RETURNTRANSFER => TRUE,
- CURLOPT_SSL_VERIFYHOST => FALSE,
- CURLOPT_SSL_VERIFYPEER => FALSE,
- CURLOPT_USERAGENT => Tweeper::$userAgent,
- ));
- curl_exec($ch);
+ CURLOPT_USERAGENT => isset($user_agent) ? $user_agent : Tweeper::$userAgent,
+ ]);
+
+ $ret = Tweeper::curlExec($ch);
+ if (FALSE === $ret) {
+ curl_close($ch);
+ return FALSE;
+ }
+
$url_info = curl_getinfo($ch);
if (FALSE === $url_info) {
- trigger_error(curl_error($ch));
+ trigger_error(curl_error($ch), E_USER_WARNING);
}
curl_close($ch);
* Generate an RSS <enclosure/> element.
*/
public static function generateEnclosure($url) {
- $supported_content_types = array(
+ $supported_content_types = [
"application/octet-stream",
"application/ogg",
"application/pdf",
"video/mp4",
"video/mpeg",
"video/ogg",
- );
+ ];
$url_info = Tweeper::getUrlInfo($url);
+ if (FALSE === $url_info) {
+ trigger_error("Failed to retrieve info for URL: " . $url, E_USER_WARNING);
+ return '';
+ }
$supported = in_array($url_info['content_type'], $supported_content_types);
if (!$supported) {
- error_log("Unsupported enclosure content type \"" . $url_info['content_type'] . "\" for URL: " . $url_info['url']);
+ trigger_error("Unsupported enclosure content type \"" . $url_info['content_type'] . "\" for URL: " . $url_info['url'], E_USER_WARNING);
return '';
}
// See http://sourceforge.net/p/feedvalidator/bugs/72/
$http_url = preg_replace("/^https/", "http", $url_info['url']);
+ // When the server does not provide a Content-Length header,
+ // curl_getinfo() would return a negative value for
+ // "download_content_length", however RSS recommends to use 0 when the
+ // enclosure's size cannot be determined.
+ // See: https://www.feedvalidator.org/docs/error/UseZeroForUnknown.html
+ $length = max($url_info['download_content_length'], 0);
+
$dom = new DOMDocument();
$enc = $dom->createElement('enclosure');
$enc->setAttribute('url', $http_url);
- $enc->setAttribute('length', $url_info['download_content_length']);
+ $enc->setAttribute('length', $length);
$enc->setAttribute('type', $url_info['content_type']);
return $enc;
$output .= " line $error->line";
- error_log($output);
+ trigger_error($output, E_USER_WARNING);
}
/**
$encoder = new XmlEncoder();
$normalizer = new ObjectNormalizer();
- $serializer = new Serializer(array($normalizer), array($encoder));
+ $serializer = new Serializer([$normalizer], [$encoder]);
- $serializer_options = array(
+ $serializer_options = [
'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);
+ trigger_error("Cannot serialize data", E_USER_WARNING);
return NULL;
}
$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);
+ trigger_error("Cannot match expression: $json_match_expr\n", E_USER_WARNING);
return NULL;
}
+ $data = json_decode($matches[1], $assoc = TRUE);
+
// The "qe" object contains elements which will result in invalid XML
// element names, so remove it.
- $data = json_decode($matches[1], $assoc = TRUE);
unset($data["qe"]);
+
+ // The "knobs" object contains elements with undefined namespaces, so
+ // remove it to silence an error message.
+ unset($data["knobs"]);
+
$json = json_encode($data);
return Tweeper::jsonToXml($json, 'instagram');
// 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));
+ $xml_data = call_user_func_array([$this, $get_xml_host_method], [$html]);
$xmlDoc->loadXML($xml_data);
}
else {
$xmlDoc->loadHTML($html);
}
- foreach (libxml_get_errors() as $xml_error) {
- Tweeper::logXmlError($xml_error);
+ if ($this->verbose_output) {
+ foreach (libxml_get_errors() as $xml_error) {
+ Tweeper::logXmlError($xml_error);
+ }
}
libxml_clear_errors();
libxml_use_internal_errors($xml_errors_value);
private function loadStylesheet($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);
+ trigger_error("Conversion to RSS not supported for $host ($stylesheet not found)", E_USER_WARNING);
return NULL;
}
- $stylesheet_contents = Tweeper::getUrlContents($stylesheet);
+ $stylesheet_contents = file_get_contents($stylesheet);
+ if (FALSE === $stylesheet_contents) {
+ trigger_error("Cannot open $stylesheet", E_USER_WARNING);
+ return NULL;
+ }
$xslDoc = new DOMDocument();
$xslDoc->loadXML($stylesheet_contents);
$xsltProcessor = new XSLTProcessor();
$xsltProcessor->registerPHPFunctions();
$xsltProcessor->setParameter('', 'generate-enclosure', $this->generate_enclosure);
+ $xsltProcessor->setParameter('', 'show-usernames', $this->show_usernames);
+ $xsltProcessor->setParameter('', 'show-multimedia', $this->show_multimedia);
$xsltProcessor->importStylesheet($xslDoc);
return $xsltProcessor;
/**
* Convert the site content to RSS.
*/
- public function tweep($src_url, $host=NULL, $validate_scheme=TRUE) {
+ public function tweep($src_url, $host = NULL, $validate_scheme = TRUE) {
$url = parse_url($src_url);
if (FALSE === $url) {
- trigger_error("Invalid URL: $src_url", E_USER_ERROR);
+ trigger_error("Invalid URL: $src_url", E_USER_WARNING);
return NULL;
}
if (TRUE === $validate_scheme) {
$scheme = $url["scheme"];
- if (!in_array($scheme, array("http", "https"))) {
- trigger_error("unsupported scheme: $scheme", E_USER_ERROR);
+ if (!in_array($scheme, ["http", "https"])) {
+ trigger_error("unsupported scheme: $scheme", E_USER_WARNING);
return NULL;
}
}
- // if the host is not given derive it from the URL
+ // If the host is not given derive it from the URL.
if (NULL === $host) {
if (empty($url["host"])) {
- trigger_error("Invalid host in URL: $src_url", E_USER_ERROR);
+ trigger_error("Invalid host in URL: $src_url", E_USER_WARNING);
return NULL;
}
// Strip the leading www. to be more forgiving on input URLs.
$html = Tweeper::getUrlContents($src_url);
if (FALSE === $html) {
+ trigger_error("Failed to retrieve $src_url", E_USER_WARNING);
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));
+ $html = call_user_func_array([$this, $preprocess_html_host_method], [$html]);
}
$xmlDoc = $this->htmlToXml($html, $host);
$output = $xsltProcessor->transformToXML($xmlDoc);
if (FALSE === $output) {
- trigger_error('XSL transformation failed.', E_USER_ERROR);
+ trigger_error('XSL transformation failed.', E_USER_WARNING);
return NULL;
}