src/Tweeper.php: add a retry mechanism for cURL sessions

[tweeper.git] / tweeper.php

diff --git a/tweeper.php b/tweeper.php
old mode 100755 (executable)
new mode 100644 (file)
index a019684..038f2b6
--- a/tweeper.php
+++ b/tweeper.php
@@ -1,109 +1,140 @@
 <?php
 <?php

-/*
- * tweeper - a Twitter to RSS web scraper
- * 
- * Copyright (C) 2013  Antonio Ospite <ospite@studenti.unina.it>
- * 
+/**
+ * @file
+ * Tweeper - a Twitter to RSS web scraper.
+ *
+ * Copyright (C) 2013-2018  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 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.
  * 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/>.
  */
 
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 

-date_default_timezone_set('UTC');
-
-function str_to_gmdate($date)
-{
-  $timestamp = strtotime($date);
-  return epoch_to_gmdate($timestamp);
-}
+require_once 'autoload.php';

 
 

-function epoch_to_gmdate($timestamp)
-{
-  return gmdate('D, d M Y H:i:s', $timestamp) . ' GMT';
-}
+use Tweeper\Tweeper;

 
 

-class Tweeper {
+date_default_timezone_set('UTC');

 
 

-  private $USER_AGENT = "Mozilla/5.0 (Windows NT 6.1; rv:22.0) Gecko/20130405 Firefox/22.0";
+/**
+ * Check if the script is being run from the command line.
+ */
+function is_cli() {
+  return (php_sapi_name() === "cli");
+}

 
 

-  public function __construct($stylesheet) {
-    $stylesheet_contents = $this->get_contents($stylesheet);
+/**
+ * Show the script usage.
+ */
+function usage($argv) {
+  if (is_cli()) {
+    $usage = "{$argv[0]} [-e|-u <0|1>|-h|--help] <src_url>\n";
+  }
+  else {
+    $usage = htmlentities("{$_SERVER['SCRIPT_NAME']}?src_url=<src_url>&generate_enclosure=<0|1>&show_usernames=<0|1>");
+  }

 
 

-    $xslDoc = new DOMDocument();
-    $xslDoc->loadXML($stylesheet_contents);
+  return "usage: $usage";
+}

 
 

-    $this->xsltProcessor = new XSLTProcessor();
-    $this->xsltProcessor->registerPHPFunctions();
-    $this->xsltProcessor->importStylesheet($xslDoc);
+/**
+ * Parse command line options.
+ */
+function parse_options_cli($argv, $argc) {
+  $options = array(
+    'generate_enclosure' => FALSE,
+    'show_usernames' => TRUE,
+  );
+
+  if ($argc < 2) {
+    return $options;

   }
 
   }
 

-  private function get_contents($uri) {
-    # https://www.wjsams.com/c/docs/Wiki/Php-HowToSetUserAgentOnFileGetContents
-    $opts = array(
-      'http' => array(
-        'method' => "GET",
-        'header' => join(array(
-          "Accept-language: en\r\n",
-          "User-Agent: {$this->USER_AGENT}\r\n"
-        ))
-      )
-    );
-
-    $context = stream_context_create($opts);
-    $contents = file_get_contents($uri, false, $context);
-    return $contents;
+  $cli_options = getopt("eu:h", array("help"));
+  foreach ($cli_options as $opt => $val) {
+    switch ($opt) {
+      case 'e':
+        $options['generate_enclosure'] = TRUE;
+        break;
+
+      case 'u':
+        $ret = filter_var($val, FILTER_VALIDATE_BOOLEAN, FILTER_NULL_ON_FAILURE);
+        if (NULL === $ret) {
+          fwrite(STDERR, "Invalid argument for the -u option.\n");
+          fwrite(STDERR, usage($argv));
+          exit(1);
+        }
+        $options['show_usernames'] = $val;
+        break;
+
+      case 'h':
+      case 'help':
+        echo usage($argv);
+        exit(0);
+
+      default:
+        fwrite(STDERR, usage($argv));
+        exit(1);
+    }

   }
 
   }
 

-  public function tweep($uri) {
-    $html = $this->get_contents($uri);
+  // For now assume that the URL is the lest argument, in the future we could
+  // switch to PHP >= 7.1 and use the $optind argument of getopt().
+  $options['src_url'] = array_pop($argv);

 
 

-    $xmlDoc = new DOMDocument();
-    $xmlDoc->loadHTML($html);
+  return $options;
+}

 
 

-    $output = $this->xsltProcessor->transformToXML($xmlDoc);
+/**
+ * Parse options passed from a query string.
+ */
+function parse_options_query_string() {
+  $options = array(
+    'generate_enclosure' => FALSE,
+    'show_usernames' => TRUE,
+  );
+
+  if (isset($_GET['src_url'])) {
+    $options['src_url'] = $_GET['src_url'];
+  }

 
 

-    if (FALSE === $output) {
-      trigger_error('XSL transformation failed.', E_USER_ERROR);
-      return NULL;
-    }
-    return $output;
+  if (isset($_GET['generate_enclosure'])) {
+    $options['generate_enclosure'] = $_GET['generate_enclosure'] == 1;

   }
   }

-}

 
 

-function usage($argv)
-{
-  if (php_sapi_name() != 'cli')
-    $usage = htmlentities("{$_SERVER['SCRIPT_NAME']}?src_url=<src_url>");
-  else
-    $usage = "{$argv[0]} <src_url>\n";
+  if (isset($_GET['show_usernames'])) {
+    $options['show_usernames'] = $_GET['show_usernames'] != 0;
+  }

 
 

-  return "usage: $usage";
+  return $options;

 }
 
 }
 

-if (isset($_GET['src_url'])) {
-  $src_url = $_GET['src_url'];
-} else if (isset($argv[1])) {
-  $src_url = $argv[1];
-} else {
-  die(usage($argv));
+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');

 }
 
 }
 

-$url = parse_url($src_url);
-if (FALSE === $url || empty($url["host"]))
-  die("Invalid url: $url\n");
-
-$stylesheet = __DIR__ . "/rss_converter_" . $url["host"] . ".xsl";
-if (FALSE === file_exists($stylesheet))
-  die("Conversion to RSS not supported: {$url["host"]}\n");
+if (!isset($options['src_url'])) {
+  fwrite($error_stream, usage(is_cli() ? $argv : NULL));
+  exit(1);
+}

 
 

-$tweeper = new Tweeper($stylesheet);
-echo $tweeper->tweep($src_url);
+$tweeper = new Tweeper($options['generate_enclosure'], $options['show_usernames']);
+$output = $tweeper->tweep($options['src_url']);
+if (is_null($output)) {
+  exit(1);
+}
+echo $output;