From: rich <rich>
Date: Fri, 8 Dec 2006 14:10:37 +0000 (+0000)
Subject: If fetching the RSS from the feed fails, keep using the old, cached
X-Git-Url: http://git.annexia.org/?a=commitdiff_plain;h=662d8a1f4bd09b346816295104daeb9673b3b280;p=cocanwiki.git

If fetching the RSS from the feed fails, keep using the old, cached
RSS (if it was in the cache).
---

diff --git a/scripts/lib/cocanwiki_func_rss.ml b/scripts/lib/cocanwiki_func_rss.ml
index dafeba7..b9d791c 100644
--- a/scripts/lib/cocanwiki_func_rss.ml
+++ b/scripts/lib/cocanwiki_func_rss.ml
@@ -1,5 +1,5 @@
 (* An RSS feed reader function.
- * $Id: cocanwiki_func_rss.ml,v 1.2 2006/12/07 17:16:17 rich Exp $
+ * $Id: cocanwiki_func_rss.ml,v 1.3 2006/12/08 14:10:37 rich Exp $
  *)
 
 open Printf
@@ -197,15 +197,24 @@ let rss r dbh hostid arg =
 	  "select t, rss from rss_cache where url = $url" in
       let need_to_fetch, rss =
 	match rows with
-	| [] -> true, "" (* not in cache, so have to fetch URL *)
+	| [] -> true, None (* not in cache, so have to fetch URL *)
 	| (t, rss) :: _ ->
 	    if Calendar.compare
 	      (Calendar.add t refresh) (Calendar.now ()) < 0 then
-	      true, ""
+	      true, Some rss
 	    else
-	      false, rss in
+	      false, Some rss in
       if need_to_fetch then (
-	let rss = fetch_url url in
+        (* If the fetch fails, keep using the old cached RSS.
+	 * fetch_url prints the error in the error log in this case.
+	 *)
+	let rss =
+	  try fetch_url url
+	  with Error _ as exn ->
+	    match rss with
+	    | Some rss -> rss
+	    | None -> raise exn in
+
 	(* This lock is OK - refetches are supposed to be infrequent. *)
 	PGSQL(dbh) "lock table rss_cache in share mode";
 	PGSQL(dbh) "delete from rss_cache where url = $url";
@@ -213,8 +222,11 @@ let rss r dbh hostid arg =
 	PGOCaml.commit dbh; (* XXX How to avoid? *)
 	PGOCaml.begin_work dbh;
 	rss
-      ) else
-	rss in
+      ) else (
+        match rss with
+	| Some rss -> rss
+	| None -> assert false
+      ) in
 
     (* Try to parse the RSS. *)
     let channel =