Diff

mod_pubsub_feed/mod_pubsub_feed.lua @ 278:653c1826739e

mod_pubsub_feed: Fetches Atom feeds and publishes to PubSub
author Kim Alvefur <zash@zash.se>
date Sat, 27 Nov 2010 04:14:53 +0100
child 279:aa0df3db4901
line wrap: on
line diff
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mod_pubsub_feed/mod_pubsub_feed.lua	Sat Nov 27 04:14:53 2010 +0100
@@ -0,0 +1,90 @@
+-- Fetches Atom feeds and publishes to PubSub nodes
+--
+-- Config:
+-- Component "pubsub.example.com" "pubsub"
+-- modules_enabled = {
+--   "pubsub_feed";
+-- }
+-- feeds = { -- node -> url
+--   telecomix = "https://status.telecomix.org/api/statuses/public_timeline.atom";
+-- }
+-- feed_pull_interval = 20 -- minutes
+
+local modules = hosts[module.host].modules;
+if not modules.pubsub then
+	module:log("warn", "Pubsub needs to be loaded on this host");
+end
+local add_task = require "util.timer".add_task;
+local date, time = os.date, os.time;
+local dt_parse = require "util.datetime".parse;
+local http = require "net.http";
+local parse_feed = require "feeds".feed_from_string;
+
+local config = module:get_option("feeds") or {
+	planet_jabber = "http://planet.jabber.org/atom.xml";
+	prosody_blog = "http://blog.prosody.im/feed/atom.xml";
+};
+local refresh_interval = (module:get_option("feed_pull_interval") or 15) * 60;
+local feed_list = { }
+for node, url in pairs(config) do
+	feed_list[node] = { url = url };
+end
+
+local function update(item, callback)
+	local headers = { };
+	if item.data and item.last_update then
+		headers["If-Modified-Since"] = date("!%a, %d %b %Y %T %Z", item.last_update);
+	end
+	http.request(item.url, {headers = headers}, function(data, code, req) 
+		if code == 200 then
+			item.data = data;
+			callback(item)
+			item.last_update = time();
+		end
+		if code == 304 then
+			item.last_update = time();
+		end
+	end);
+end
+
+local actor = module.host.."/"..module.name;
+
+local function refresh_feeds()
+	for node, item in pairs(feed_list) do
+		update(item, function(item)
+			local feed = parse_feed(item.data);
+			module:log("debug", "node: %s", node);
+			for _, entry in ipairs(feed) do
+				entry.attr.xmlns = "http://www.w3.org/2005/Atom";
+
+				local e_published = entry:get_child("published");
+				e_published = e_published and e_published[1];
+				e_published = e_published and dt_parse(e_published);
+				local e_updated = entry:get_child("updated");
+				e_updated = e_updated and e_updated[1];
+				e_updated = e_updated and dt_parse(e_updated);
+
+				local timestamp = e_published or e_updated or nil;
+				module:log("debug", "timestamp is %s, item.last_update is %s", tostring(timestamp), tostring(item.last_update));
+				if not timestamp or not item.last_update or timestamp > item.last_update then
+					local id = entry:get_child("id");
+					id = id[1] or item.url.."#"..timestamp;
+					module:log("debug", "publishing to %s, id %s", node, id);
+					modules.pubsub.service:publish(node, actor, id, entry)
+				end
+			end
+		end);
+	end
+	return refresh_interval;
+end
+
+function init()
+	add_task(0, refresh_feeds);
+end
+
+if prosody.start_time then -- already started
+	init();
+else
+	prosody.events.add_handler("server-started", init);
+end
+