--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mod_smacks_noerror/README.markdown	Tue Nov 22 21:14:47 2016 +0100
@@ -0,0 +1,37 @@
+---
+labels:
+- 'Stage-Alpha'
+summary: Monkeypatch mod_smacks to silently discard unacked message stanzas when a hibernation times out
+...
+
+Introduction
+============
+
+By default mod_smacks sends back error stanzas for every unacked message
+stanza when the hibernation times out.
+This leads to "message not delivered" errors displayed in clients.
+
+When you are certain that *all* your clients use MAM, this is unneccessary and
+confuses users (the message will eventually be delivered via MAM).
+
+This module therefore monkeypatches mod_smacks to silently drop those
+unacked message stanzas instead of sending error replies.
+Unacked iq stanzas are still answered with an error reply though.
+
+Warning
+=======
+
+You most certainly *should not* use this module if you cannot be certain
+that *all* your clients support and use MAM!
+
+Compatibility
+=============
+
+  ----- -------------------------------------------------------------------
+  trunk Untested
+  0.10  Works
+  0.9   Untested but should work
+  0.8   Untested but should work, use version [7693724881b3] of mod_smacks
+  ----- -------------------------------------------------------------------
+
+[7693724881b3]: //hg.prosody.im/prosody-modules/raw-file/7693724881b3/mod_smacks/mod_smacks.lua

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mod_smacks_noerror/mod_smacks_noerror.lua	Tue Nov 22 21:14:47 2016 +0100
@@ -0,0 +1,33 @@
+local t_insert = table.insert;
+
+local mod_smacks = module:depends"smacks"
+
+local function discard_unacked_messages(session)
+	local queue = session.outgoing_stanza_queue;
+	local replacement_queue = {};
+	session.outgoing_stanza_queue = replacement_queue;
+
+	for _, stanza in ipairs(queue) do
+		if stanza.name == "message" and stanza.attr.xmlns == nil and
+				( stanza.attr.type == "chat" or ( stanza.attr.type or "normal" ) == "normal" ) then
+			-- do nothing here for normal messages and don't send out "message delivery errors",
+			-- because messages are already in MAM at this point (no need to frighten users)
+		else
+			t_insert(replacement_queue, stanza);
+		end
+	end
+end
+
+local handle_unacked_stanzas = mod_smacks.handle_unacked_stanzas;
+
+mod_smacks.handle_unacked_stanzas = function (session)
+	-- Only deal with authenticated (c2s) sessions
+	if session.username then
+		discard_unacked_messages(session)
+	end
+	return handle_unacked_stanzas(session);
+end
+
+function module.unload()
+	mod_smacks.handle_unacked_stanzas = handle_unacked_stanzas;
+end