# HG changeset patch
# User Matthew Wild <mwild1@gmail.com>
# Date 1519078658 0
# Node ID 7c16afc70d11f3bb2a0999da261f912519b2f72b
# Parent  6f289283feb17c3a902de2bda4c901d10633ad56
mod_muc_eventsource: New module forked from mod_pubsub_eventsource, exposes room message stream over SSE

diff -r 6f289283feb1 -r 7c16afc70d11 mod_muc_eventsource/README.markdown
--- /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
+  ------- --------------
diff -r 6f289283feb1 -r 7c16afc70d11 mod_muc_eventsource/mod_muc_eventsource.lua
--- /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);