--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/mod_pubsub_hub/mod_pubsub_hub.lua Wed Aug 01 16:11:12 2012 +0200
@@ -0,0 +1,241 @@
+-- Copyright (C) 2011 - 2012 Kim Alvefur
+--
+-- This file is MIT/X11 licensed.
+
+local http = require "net.http";
+local formdecode = http.formdecode;
+local formencode = http.formencode;
+local uuid = require "util.uuid".generate;
+local hmac_sha1 = require "util.hmac".sha1;
+local json_encode = require "util.json".encode;
+local time = os.time;
+local m_min, m_max = math.min, math.max;
+local tostring = tostring;
+local xmlns_pubsub = "http://jabber.org/protocol/pubsub";
+local xmlns_pubsub_event = xmlns_pubsub .. "#event";
+local subs_by_topic = module:shared"subscriptions";
+
+local max_lease, min_lease, default_lease = 86400, 600, 3600;
+
+module:depends"pubsub";
+
+local valid_modes = { ["subscribe"] = true, ["unsubscribe"] = true, }
+
+local function do_subscribe(subscription)
+ -- FIXME handle other states
+ if subscription.state == "subscribed" then
+ local ok, err = hosts[module.host].modules.pubsub.service:add_subscription(subscription.topic, true, module.host);
+ module:log(ok and "debug" or "error", "add_subscription() => %s, %s", tostring(ok), tostring(err));
+ end
+end
+
+local function handle_request(event)
+ local request, response = event.request, event.response;
+ local method, body = request.method, request.body;
+
+ local query = request.url.query or {};
+ if query and type(query) == "string" then
+ query = formdecode(query);
+ end
+ if body and request.headers.content_type == "application/x-www-form-urlencoded" then
+ body = formdecode(body);
+ end
+
+ if method == "POST" then
+ -- Subscription request
+ if body["hub.callback"] and body["hub.mode"] and valid_modes[body["hub.mode"]]
+ and body["hub.topic"] and body["hub.verify"] then
+
+ -- http://pubsubhubbub.googlecode.com/svn/trunk/pubsubhubbub-core-0.3.html#anchor5
+ local callback = body["hub.callback"];
+ local mode = body["hub.mode"];
+ local topic = body["hub.topic"];
+ local lease_seconds = m_min(tonumber(body["hub.lease_seconds"]) or default_lease, max_lease);
+ local secret = body["hub.secret"];
+ local verify_token = body["hub.verify_token"];
+
+ module:log("debug", "topic is "..(type(topic)=="string" and "%q" or "%s"), topic);
+
+ if not subs_by_topic[topic] then
+ subs_by_topic[topic] = {};
+ end
+ local subscription = subs_by_topic[topic][callback];
+
+ local verify_modes = {};
+ for i=1,#body do
+ if body[i].name == "hub.verify" then
+ verify_modes[body[i].value] = true;
+ end
+ end
+
+ subscription = subscription or {
+ id = uuid(),
+ callback = callback,
+ topic = topic,
+ state = "unsubscribed",
+ secret = secret,
+ want_state = mode,
+ lease_seconds = lease_seconds,
+ expires = time() + lease_seconds,
+ };
+ subs_by_topic[topic][callback] = subscription;
+ local challenge = uuid();
+
+ local callback_url = callback .. (callback:match("%?") and "&" or "?") .. formencode{
+ ["hub.mode"] = mode,
+ ["hub.topic"] = topic,
+ ["hub.challenge"] = challenge,
+ ["hub.lease_seconds"] = tostring(lease_seconds),
+ ["hub.verify_token"] = verify_token,
+ }
+ module:log("debug", require"util.serialization".serialize(verify_modes));
+ if verify_modes["async"] then
+ module:log("debug", "Sending async verification request to %s for %s", tostring(callback_url), tostring(subscription));
+ http.request(callback_url, nil, function(body, code)
+ if body == challenge and code > 199 and code < 300 then
+ if not subscription.want_state then
+ module:log("warn", "Verification of already verified request, probably");
+ return;
+ end
+ subscription.state = subscription.want_state .. "d";
+ subscription.want_state = nil;
+ module:log("debug", "calling do_subscribe()");
+ do_subscribe(subscription);
+ subs_by_topic[topic][callback] = subscription;
+ else
+ module:log("warn", "status %d and body was %q", tostring(code), tostring(body));
+ subs_by_topic[topic][callback] = subscription;
+ end
+ end)
+ return 202;
+ elseif verify_modes["sync"] then
+ http.request(callback_url, nil, function(body, code)
+ if body == challenge and code > 199 and code < 300 then
+ if not subscription.want_state then
+ module:log("warn", "Verification of already verified request, probably");
+ return;
+ end
+ if mode == "unsubscribe" then
+ subs_by_topic[topic][callback] = nil;
+ else
+ subscription.state = subscription.want_state .. "d";
+ subscription.want_state = nil;
+ module:log("debug", "calling do_subscribe()");
+ do_subscribe(subscription);
+ subs_by_topic[topic][callback] = subscription;
+ end
+ else
+ subs_by_topic[topic][callback] = subscription;
+ end
+ response.status = 204;
+ response:send();
+ end)
+ return true;
+ end
+ return 400;
+ else
+ response.status = 400;
+ response.headers.content_type = "text/html";
+ return "<h1>Bad Request</h1>\n<a href='http://pubsubhubbub.googlecode.com/svn/trunk/pubsubhubbub-core-0.3.html#anchor5'>Missing required parameter(s)</a>\n"
+ end
+ end
+end
+
+local function periodic()
+ local now = time();
+ local next_check = now + max_lease;
+ local purge = false
+ for topic, callbacks in pairs(subs_by_topic) do
+ for callback, subscription in pairs(callbacks) do
+ if subscription.mode == "subscribed" then
+ if subscription.expires < now then
+ -- Subscription has expired, drop it.
+ purge = true
+ end
+ if subscription.expires < now + min_lease then
+ -- Subscription set to expire soon, re-confirm it.
+ local challenge = uuid();
+ local callback_url = callback .. (callback:match("%?") and "&" or "?") .. formencode{
+ ["hub.mode"] = subscription.state,
+ ["hub.topic"] = topic,
+ ["hub.challenge"] = challenge,
+ ["hub.lease_seconds"] = subscription.lease_seconds,
+ ["hub.verify_token"] = subscription.verify_token,
+ }
+ http.request(callback_url, nil, function(body, code)
+ if body == challenge and code > 199 and code < 300 then
+ subscription.expires = now + subscription.lease_seconds;
+ end
+ end);
+ else
+ next_check = m_min(next_check, now - subscription.expires)
+ end
+ end
+ end
+ if purge then
+ local new_callbacks = {};
+ for callback, subscription in pairs(callbacks) do
+ if (subscription.state == "subscribed" and subscription.expires < now)
+ and subscription.want_state ~= "remove" then
+ new_callbacks[callback] = subscription;
+ end
+ end
+ subs_by_topic[topic] = new_callbacks
+ end
+ end
+ return m_max(next_check - min_lease, min_lease);
+end
+
+local function on_notify(subscription, content)
+ local body = tostring(content);
+ local headers = {
+ ["Content-Type"] = "application/xml",
+ };
+ if subscription.secret then
+ headers["X-Hub-Signature"] = "sha1="..hmac_sha1(subscription.secret, body, true);
+ end
+ http.request(subscription.callback, { method = "POST", body = body, headers = headers }, function(body, code)
+ if code >= 200 and code <= 299 then
+ module:log("debug", "Delivered");
+ else
+ module:log("warn", "Got status code %d on delivery to %s", tonumber(code) or -1, tostring(subscription.callback));
+ -- TODO Retry
+ -- ... but the spec says that you should not retry, wtf?
+ end
+ end);
+end
+
+module:hook("message/host", function(event)
+ local stanza = event.stanza;
+ if stanza.attr.from ~= module.host then return end;
+
+ for pubsub_event in stanza:childtags("event", xmlns_pubsub_event) do
+ local items = pubsub_event:get_child("items");
+ local node = items.attr.node;
+ if items and node and subs_by_topic[node] then
+ for item in items:childtags("item") do
+ local content = item.tags[1];
+ for callback, subscription in pairs(subs_by_topic[node]) do
+ on_notify(subscription, content)
+ end
+ end
+ end
+ end
+ return true;
+end, 10);
+
+module:depends"http";
+module:provides("http", {
+ default_path = "/hub";
+ route = {
+ POST = handle_request;
+ GET = function()
+ return json_encode(subs_by_topic);
+ end;
+ ["GET /topic/*"] = function(event, path)
+ return json_encode(subs_by_topic[path])
+ end;
+ };
+});
+
+module:add_timer(1, periodic);