support If-Modified-Since

diff --git a/include/functions.php b/include/functions.php
index 36d349b54342b0261f1c1a4993d0b745118815f3..307f662009b14dc83c304a86477f4a5e57c96508 100644 (file)
--- a/include/functions.php
+++ b/include/functions.php
@@ -6,6 +6,7 @@
        define('PLUGIN_FEED_BASE_INDEX', -128);
 
        $fetch_last_error = false;
+       $fetch_last_error_code = false;
        $pluginhost = false;
 
        function __autoload($class) {
@@ -287,9 +288,10 @@
                }
        }
 
-       function fetch_file_contents($url, $type = false, $login = false, $pass = false, $post_query = false, $timeout = false) {
+       function fetch_file_contents($url, $type = false, $login = false, $pass = false, $post_query = false, $timeout = false, $timestamp = 0) {
 
                global $fetch_last_error;
+               global $fetch_last_error_code;
 
                if (function_exists('curl_init') && !ini_get("open_basedir")) {
 
@@ -299,6 +301,11 @@
                                $ch = curl_init($url);
                        }
 
+                       if ($timestamp) {
+                               curl_setopt($ch, CURLOPT_HTTPHEADER,
+                                       array("If-Modified-Since: ".gmdate('D, d M Y H:i:s \G\M\T', $timestamp)));
+                       }
+
                        curl_setopt($ch, CURLOPT_CONNECTTIMEOUT, $timeout ? $timeout : 15);
                        curl_setopt($ch, CURLOPT_TIMEOUT, $timeout ? $timeout : 45);
                        curl_setopt($ch, CURLOPT_FOLLOWLOCATION, !ini_get("safe_mode"));
@@ -335,6 +342,8 @@
                        $http_code = curl_getinfo($ch, CURLINFO_HTTP_CODE);
                        $content_type = curl_getinfo($ch, CURLINFO_CONTENT_TYPE);
 
+                       $fetch_last_error_code = $http_code;
+
                        if ($http_code != 200 || $type && strpos($content_type, "$type") === false) {
                                if (curl_errno($ch) != 0) {
                                        $fetch_last_error = curl_errno($ch) . " " . curl_error($ch);

diff --git a/include/rssfuncs.php b/include/rssfuncs.php
index e82e94b099f1d99ed665df7acd27a3c0e94a1e73..7c668f69f3122d8083b7f72900014894b7478eec 100644 (file)
--- a/include/rssfuncs.php
+++ b/include/rssfuncs.php
@@ -239,6 +239,7 @@
 
                $rss = false;
                $rss_hash = false;
+               $cache_timestamp = file_exists($cache_filename) ? filemtime($cache_filename) : 0;
 
                if (file_exists($cache_filename) &&
                        is_readable($cache_filename) &&
@@ -261,11 +262,11 @@
 
                        if (!$feed_data) {
                                if ($debug_enabled) {
-                                       _debug("update_rss_feed: fetching [$fetch_url]...");
+                                       _debug("update_rss_feed: fetching [$fetch_url] (ts: $cache_timestamp)");
                                }
 
                                $feed_data = fetch_file_contents($fetch_url, false,
-                                       $auth_login, $auth_pass, false, $no_cache ? 15 : 45);
+                                       $auth_login, $auth_pass, false, $no_cache ? 15 : 45, $cache_timestamp);
 
                                if ($debug_enabled) {
                                        _debug("update_rss_feed: fetch done.");
@@ -275,12 +276,22 @@
 
                        if (!$feed_data) {
                                global $fetch_last_error;
+                               global $fetch_last_error_code;
 
                                if ($debug_enabled) {
-                                       _debug("update_rss_feed: unable to fetch: $fetch_last_error");
+                                       _debug("update_rss_feed: unable to fetch: $fetch_last_error [$fetch_last_error_code]");
                                }
 
-                               $error_escaped = db_escape_string($link, $fetch_last_error);
+                               $error_escaped = '';
+
+                               // If-Modified-Since
+                               if ($fetch_last_error_code != 304) {
+                                       $error_escaped = db_escape_string($link, $fetch_last_error);
+                               } else {
+                                       if ($debug_enabled) {
+                                               _debug("update_rss_feed: source claims data not modified, nothing to do.");
+                                       }
+                               }
 
                                db_query($link,
                                        "UPDATE ttrss_feeds SET last_error = '$error_escaped',