tweeper.php: fix validation when generating enclosure elements

[tweeper.git] / tweeper.php

diff --git a/tweeper.php b/tweeper.php
index 4be5c7d..d084398 100644 (file)
--- a/tweeper.php
+++ b/tweeper.php
@@ -1,19 +1,19 @@
 <?php
 /*
  * tweeper - a Twitter to RSS web scraper
- * 
- * Copyright (C) 2013-2014  Antonio Ospite <ao2@ao2.it>
- * 
+ *
+ * Copyright (C) 2013-2015  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
  * 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 <http://www.gnu.org/licenses/>.
  */
@@ -24,16 +24,8 @@ class Tweeper {
 
   private static $USER_AGENT = "Mozilla/5.0 (Windows NT 6.1; rv:22.0) Gecko/20130405 Firefox/22.0";
 
-  public function __construct($stylesheet, $generate_enclosure = FALSE) {
-    $stylesheet_contents = $this->get_contents($stylesheet);
-
-    $xslDoc = new DOMDocument();
-    $xslDoc->loadXML($stylesheet_contents);
-
-    $this->xsltProcessor = new XSLTProcessor();
-    $this->xsltProcessor->registerPHPFunctions();
-    $this->xsltProcessor->setParameter('', 'generateEnclosure', $generate_enclosure);
-    $this->xsltProcessor->importStylesheet($xslDoc);
+  public function __construct($generate_enclosure = FALSE) {
+    $this->generate_enclosure = $generate_enclosure;
   }
 
   public static function epoch_to_gmdate($timestamp)
@@ -104,7 +96,11 @@ class Tweeper {
       "video/ogg",
     );
 
-    $url_info = Tweeper::get_info($url);
+    // 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);
+
+    $url_info = Tweeper::get_info($http_url);
 
     $supported = in_array($url_info['content_type'], $supported_content_types);
     if (!$supported) {
@@ -152,9 +148,27 @@ class Tweeper {
     error_log($output);
   }
 
-  public function tweep($uri) {
-    $html = Tweeper::get_contents($uri);
+  private function load_stylesheet($host) {
+    $stylesheet = "file://" . __DIR__ . "/rss_converter_" . $host . ".xsl";
+    if (FALSE === file_exists($stylesheet)) {
+      trigger_error("Conversion to RSS not supported: $host", E_USER_ERROR);
+      return NULL;
+    }
+
+    $stylesheet_contents = $this->get_contents($stylesheet);
+
+    $xslDoc = new DOMDocument();
+    $xslDoc->loadXML($stylesheet_contents);
+
+    $xsltProcessor = new XSLTProcessor();
+    $xsltProcessor->registerPHPFunctions();
+    $xsltProcessor->setParameter('', 'generateEnclosure', $this->generate_enclosure);
+    $xsltProcessor->importStylesheet($xslDoc);
 
+    return $xsltProcessor;
+  }
+
+  private function html_to_xml($html) {
     $xmlDoc = new DOMDocument();
 
     // Handle warnings and errors when loading invalid HTML.
@@ -166,7 +180,32 @@ class Tweeper {
     libxml_clear_errors();
     libxml_use_internal_errors($xml_errors_value);
 
-    $output = $this->xsltProcessor->transformToXML($xmlDoc);
+    return $xmlDoc;
+  }
+
+  public function tweep($src_url) {
+    $url = parse_url($src_url);
+    if (FALSE === $url || empty($url["host"])) {
+      trigger_error("Invalid url: $src_url", E_USER_ERROR);
+      return NULL;
+    }
+
+    $xsltProcessor = $this->load_stylesheet($url["host"]);
+    if (NULL === $xsltProcessor) {
+      return NULL;
+    }
+
+    $html = $this->get_contents($src_url);
+    if (FALSE === $html) {
+      return NULL;
+    }
+
+    $xmlDoc = $this->html_to_xml($html);
+    if (NULL === $xmlDoc) {
+      return NULL;
+    }
+
+    $output = $xsltProcessor->transformToXML($xmlDoc);
 
     if (FALSE === $output) {
       trigger_error('XSL transformation failed.', E_USER_ERROR);
@@ -245,17 +284,5 @@ if (!isset($options['src_url'])) {
   exit(1);
 }
 
-$url = parse_url($options['src_url']);
-if (FALSE === $url || empty($url["host"])) {
-  fwrite($ERROR_STREAM, "Invalid url: ${options['src_url']}\n");
-  exit(1);
-}
-
-$stylesheet = "file://" . __DIR__ . "/rss_converter_" . $url["host"] . ".xsl";
-if (FALSE === file_exists($stylesheet)) {
-  fwrite($ERROR_STREAM, "Conversion to RSS not supported: {$url["host"]}\n");
-  exit(1);
-}
-
-$tweeper = new Tweeper($stylesheet, $options['generate_enclosure']);
+$tweeper = new Tweeper($options['generate_enclosure']);
 echo $tweeper->tweep($options['src_url']);