mod_muc_eventsource: New module forked from mod_pubsub_eventsource, exposes room message stream over SSE
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/mod_muc_eventsource/README.markdown Mon Feb 19 22:17:38 2018 +0000
@@ -0,0 +1,78 @@
+---
+labels: 'Stage-Beta'
+summary: Subscribe to MUC rooms using the HTML5 EventSource API
+...
+
+Introduction
+------------
+
+This module and its docs shamelessly forked from mod_pubsub_eventsource.
+
+[Server-Sent Events](https://en.wikipedia.org/wiki/Server-sent_events)
+is a simple HTTP/line-based protocol supported in HTML5, making it easy
+to receive a stream of "events" in realtime using the Javascript
+[EventSource
+API](https://developer.mozilla.org/en-US/docs/Web/API/EventSource).
+
+EventSource is supported in [most modern
+browsers](http://caniuse.com/#feat=eventsource), and for the remainder
+there are 'polyfill' compatibility layers such as
+[EventSource.js](https://github.com/remy/polyfills/blob/master/EventSource.js)
+and [jquery.eventsource](https://github.com/rwldrn/jquery.eventsource).
+
+Details
+-------
+
+Subscribing to a node from Javascript is easy:
+
+ var source = new EventSource('http://muc.example.org:5280/eventsource/myroom');
+ source.onmessage = function (event) {
+ console.log(event.data); // Do whatever you want with the data here
+ };
+
+### Access control
+
+Be warned that this module currently performs no access control. It will expose
+the messages of ALL rooms on the host it is loaded on. This may be changed in
+future revisions.
+
+### Cross-domain issues
+
+The same cross-domain restrictions apply to EventSource that apply to
+BOSH, and support for CORS is not clearly standardized yet. You may want
+to proxy connections through your web server for this reason. See [BOSH:
+Cross-domain
+issues](https://prosody.im/doc/setting_up_bosh#proxying_requests) for
+more information.
+
+Configuration
+-------------
+
+There is no special configuration for this module. Simply load it onto a
+MUC component like so:
+
+ Component "muc.example.org" "muc"
+ modules_enabled = { "muc_eventsource" }
+
+As it uses HTTP to serve the event streams, you can use Prosody's
+standard [HTTP configuration options](https://prosody.im/doc/http) to
+control how/where the streams are served.
+
+**Note about URLs:** It is important to get the event streams from the
+correct hostname (that of the MUC host). An example stream URL is
+`http://muc.example.org:5280/eventsource/myroom`. If you need to
+access the streams using another hostname (e.g. `example.org`) you can
+use the `http_host` option under the Component, e.g.
+`http_host = "example.org"`. For more information see the ['Virtual
+Hosts'](https://prosody.im/doc/http#virtual_hosts) section of our HTTP
+documentation.
+
+Compatibility
+-------------
+
+ ------- --------------
+ 0.10 ?
+ 0.9 ?
+ 0.8 Doesn't work
+ Trunk Works
+ ------- --------------
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/mod_muc_eventsource/mod_muc_eventsource.lua Mon Feb 19 22:17:38 2018 +0000
@@ -0,0 +1,75 @@
+module:depends("http");
+
+local jid_split = require "util.jid".split;
+local json = require "util.json";
+
+local streams = {};
+
+function client_closed(response)
+ local node = response._eventsource_node;
+ module:log("debug", "Destroying client for %q", node);
+ streams[node][response] = nil;
+ if next(streams[node]) == nil then
+ streams[node] = nil;
+ end
+end
+
+function serve_stream(event, node)
+ module:log("debug", "Client subscribed to: %s", node);
+
+ local response = event.response;
+ response.on_destroy = client_closed;
+ response._eventsource_node = node;
+
+ response.conn:write(table.concat({
+ "HTTP/1.1 200 OK";
+ "Content-Type: text/event-stream";
+ "Access-Control-Allow-Origin: *";
+ "Access-Control-Allow-Methods: GET";
+ "Access-Control-Max-Age: 7200";
+ "";
+ "";
+ }, "\r\n"));
+
+ local clientlist = streams[node];
+ if not clientlist then
+ clientlist = {};
+ streams[node] = clientlist;
+ end
+ clientlist[response] = response.conn;
+
+ return true;
+end
+
+function handle_message(event)
+ local room, stanza = event.room, event.stanza;
+ local node = (jid_split(event.room.jid));
+ local clientlist = streams[node];
+ if not clientlist then module:log("debug", "No clients for %q", node); return; end
+
+ -- Extract body from message
+ local body = event.stanza:get_child_text("body");
+ if not body then
+ return;
+ end
+ local nick = select(3, jid_split(stanza.attr.from));
+ -- Encode body and broadcast to eventsource subscribers
+ local json_data = json.encode({
+ nick = nick;
+ body = body;
+ });
+ local data = "data: "..json_data:gsub("\n", "\ndata: \n").."\n\n";
+ for response, conn in pairs(clientlist) do
+ conn:write(data);
+ end
+end
+
+module:provides("http", {
+ name = "eventsource";
+ route = {
+ ["GET /*"] = serve_stream;
+ };
+});
+
+
+module:hook("muc-broadcast-message", handle_message);