# HG changeset patch
# User Matthew Wild <mwild1@gmail.com>
# Date 1275184039 -3600
# Node ID f5ac4e39e84f8b822c7707ffd3f54fd23d418126
# Parent  91e80e9f0259f62d9def1703d409cf40e699792a
verse.plugins.session: Only negotiate session when support is advertised by the server, and not marked as optional (saves a round-trip in a lot of cases)

diff -r 91e80e9f0259 -r f5ac4e39e84f plugins/session.lua
--- a/plugins/session.lua	Sun May 30 02:44:29 2010 +0100
+++ b/plugins/session.lua	Sun May 30 02:47:19 2010 +0100
@@ -2,19 +2,28 @@
 local xmlns_session = "urn:ietf:params:xml:ns:xmpp-session";
 
 function verse.plugins.session(stream)
-	local function handle_binding(jid)
-		stream:debug("Establishing Session...");
-		stream:send_iq(st.iq({ type = "set" }):tag("session", {xmlns=xmlns_session}),
-			function (reply)
-				if reply.attr.type == "result" then
-					stream:event("session-success");
-				elseif reply.attr.type == "error" then
-					local err = reply:child_with_name("error");
-					local type, condition, text = reply:get_error();
-					stream:event("session-failure", { error = condition, text = text, type = type });
-				end
-			end);
+	
+	local function handle_features(features)
+		local session_feature = features:get_child("session", xmlns_session);
+		if session_feature and not session_feature:get_child("optional") then
+			local function handle_binding(jid)
+				stream:debug("Establishing Session...");
+				stream:send_iq(st.iq({ type = "set" }):tag("session", {xmlns=xmlns_session}),
+					function (reply)
+						if reply.attr.type == "result" then
+							stream:event("session-success");
+						elseif reply.attr.type == "error" then
+							local err = reply:child_with_name("error");
+							local type, condition, text = reply:get_error();
+							stream:event("session-failure", { error = condition, text = text, type = type });
+						end
+					end);
+				return true;
+			end
+			stream:hook("binding-success", handle_binding);
+		end
 	end
-	stream:hook("binding-success", handle_binding);
+	stream:hook("stream-features", handle_features);
+	
 	return true;
 end