--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mod_mam_sql/mod_mam_sql.lua	Mon Sep 17 20:14:26 2012 +0200
@@ -0,0 +1,433 @@
+-- XEP-0313: Message Archive Management for Prosody
+-- Copyright (C) 2011-2012 Kim Alvefur
+--
+-- This file is MIT/X11 licensed.
+
+local xmlns_mam     = "urn:xmpp:mam:tmp";
+local xmlns_delay   = "urn:xmpp:delay";
+local xmlns_forward = "urn:xmpp:forward:0";
+
+local st = require "util.stanza";
+local rsm = module:require "mod_mam/rsm";
+local jid_bare = require "util.jid".bare;
+local jid_split = require "util.jid".split;
+local jid_prep = require "util.jid".prep;
+local host = module.host;
+
+local dm_load = require "util.datamanager".load;
+local dm_store = require "util.datamanager".store;
+local rm_load_roster = require "core.rostermanager".load_roster;
+
+local serialize, deserialize = require"util.json".encode, require"util.json".decode;
+local unpack = unpack;
+local tostring = tostring;
+local time_now = os.time;
+local t_insert = table.insert;
+local m_min = math.min;
+local timestamp, timestamp_parse = require "util.datetime".datetime, require "util.datetime".parse;
+local default_max_items, max_max_items = 20, module:get_option_number("max_archive_query_results", 50);
+local global_default_policy = module:get_option("default_archive_policy", false);
+-- TODO Should be possible to enforce it too
+
+local sql, setsql, getsql = {};
+do -- SQL stuff
+local dburi;
+local connection;
+local connections = module:shared "/*/sql/connection-cache";
+local build_url = require"socket.url".build;
+local resolve_relative_path = require "core.configmanager".resolve_relative_path;
+local params = module:get_option("mam_sql", module:get_option("sql"));
+
+local function db2uri(params)
+	return build_url{
+		scheme = params.driver,
+		user = params.username,
+		password = params.password,
+		host = params.host,
+		port = params.port,
+		path = params.database,
+	};
+end
+
+local function test_connection()
+	if not connection then return nil; end
+	if connection:ping() then
+		return true;
+	else
+		module:log("debug", "Database connection closed");
+		connection = nil;
+		connections[dburi] = nil;
+	end
+end
+local function connect()
+	if not test_connection() then
+		prosody.unlock_globals();
+		local dbh, err = DBI.Connect(
+			params.driver, params.database,
+			params.username, params.password,
+			params.host, params.port
+		);
+		prosody.lock_globals();
+		if not dbh then
+			module:log("debug", "Database connection failed: %s", tostring(err));
+			return nil, err;
+		end
+		module:log("debug", "Successfully connected to database");
+		dbh:autocommit(false); -- don't commit automatically
+		connection = dbh;
+
+		connections[dburi] = dbh;
+	end
+	return connection;
+end
+
+do -- process options to get a db connection
+	local ok;
+	prosody.unlock_globals();
+	ok, DBI = pcall(require, "DBI");
+	if not ok then
+		package.loaded["DBI"] = {};
+		module:log("error", "Failed to load the LuaDBI library for accessing SQL databases: %s", DBI);
+		module:log("error", "More information on installing LuaDBI can be found at http://prosody.im/doc/depends#luadbi");
+	end
+	prosody.lock_globals();
+	if not ok or not DBI.Connect then
+		return; -- Halt loading of this module
+	end
+
+	params = params or { driver = "SQLite3" };
+	
+	if params.driver == "SQLite3" then
+		params.database = resolve_relative_path(prosody.paths.data or ".", params.database or "prosody.sqlite");
+	end
+	
+	assert(params.driver and params.database, "Both the SQL driver and the database need to be specified");
+
+	dburi = db2uri(params);
+	connection = connections[dburi];
+	
+	assert(connect());
+	
+end
+
+function getsql(sql, ...)
+	if params.driver == "PostgreSQL" then
+		sql = sql:gsub("`", "\"");
+	end
+	-- do prepared statement stuff
+	local stmt, err = connection:prepare(sql);
+	if not stmt and not test_connection() then error("connection failed"); end
+	if not stmt then module:log("error", "QUERY FAILED: %s %s", err, debug.traceback()); return nil, err; end
+	-- run query
+	local ok, err = stmt:execute(...);
+	if not ok and not test_connection() then error("connection failed"); end
+	if not ok then return nil, err; end
+	
+	return stmt;
+end
+function setsql(sql, ...)
+	local stmt, err = getsql(sql, ...);
+	if not stmt then return stmt, err; end
+	return stmt:affected();
+end
+function sql.rollback(...)
+	if connection then connection:rollback(); end -- FIXME check for rollback error?
+	return ...;
+end
+function sql.commit(...)
+	if not connection:commit() then return nil, "SQL commit failed"; end
+	return ...;
+end
+
+end
+
+-- For translating preference names from string to boolean and back
+local default_attrs = {
+	always = true, [true] = "always",
+	never = false, [false] = "never",
+	roster = "roster",
+}
+
+do
+	local prefs_format = {
+		[false] = "roster",
+		-- default ::= true | false | "roster"
+		-- true = always, false = never, nil = global default
+		["romeo@montague.net"] = true, -- always
+		["montague@montague.net"] = false, -- newer
+	};
+end
+
+local archive_store = "archive2";
+local prefs_store = archive_store .. "_prefs";
+local function get_prefs(user)
+	return dm_load(user, host, prefs_store) or
+		{ [false] = global_default_policy };
+end
+local function set_prefs(user, prefs)
+	return dm_store(user, host, prefs_store, prefs);
+end
+
+
+-- Handle prefs.
+module:hook("iq/self/"..xmlns_mam..":prefs", function(event)
+	local origin, stanza = event.origin, event.stanza;
+	local user = origin.username;
+	if stanza.attr.type == "get" then
+		local prefs = get_prefs(user);
+		local default = prefs[false];
+		default = default ~= nil and default_attrs[default] or global_default_policy;
+		local reply = st.reply(stanza):tag("prefs", { xmlns = xmlns_mam, default = default })
+		local always = st.stanza("always");
+		local never = st.stanza("never");
+		for k,v in pairs(prefs) do
+			if k then
+				(v and always or never):tag("jid"):text(k):up();
+			end
+		end
+		reply:add_child(always):add_child(never);
+		origin.send(reply);
+		return true
+	else -- type == "set"
+		local prefs = {};
+		local new_prefs = stanza:get_child("prefs", xmlns_mam);
+		local new_default = new_prefs.attr.default;
+		if new_default then
+			prefs[false] = default_attrs[new_default];
+		end
+
+		local always = new_prefs:get_child("always");
+		if always then
+			for rule in always:childtags("jid") do
+				local jid = rule:get_text();
+				prefs[jid] = true;
+			end
+		end
+
+		local never = new_prefs:get_child("never");
+		if never then
+			for rule in never:childtags("jid") do
+				local jid = rule:get_text();
+				prefs[jid] = false;
+			end
+		end
+
+		local ok, err = set_prefs(user, prefs);
+		if not ok then
+			origin.send(st.error_reply(stanza, "cancel", "internal-server-error", "Error storing preferences: "..tostring(err)));
+		else
+			origin.send(st.reply(stanza));
+		end
+		return true
+	end
+end);
+
+-- Handle archive queries
+module:hook("iq/self/"..xmlns_mam..":query", function(event)
+	local origin, stanza = event.origin, event.stanza;
+	local query = stanza.tags[1];
+	if stanza.attr.type == "get" then
+		local qid = query.attr.queryid;
+
+		-- Search query parameters
+		local qwith = query:get_child_text("with");
+		local qstart = query:get_child_text("start");
+		local qend = query:get_child_text("end");
+		local qset = rsm.get(query);
+		module:log("debug", "Archive query, id %s with %s from %s until %s)",
+			tostring(qid), qwith or "anyone", qstart or "the dawn of time", qend or "now");
+
+		if qstart or qend then -- Validate timestamps
+			local vstart, vend = (qstart and timestamp_parse(qstart)), (qend and timestamp_parse(qend))
+			if (qstart and not vstart) or (qend and not vend) then
+				origin.send(st.error_reply(stanza, "modify", "bad-request", "Invalid timestamp"))
+				return true
+			end
+			qstart, qend = vstart, vend;
+		end
+
+		local qres;
+		if qwith then -- Validate the 'with' jid
+			local pwith = qwith and jid_prep(qwith);
+			if pwith and not qwith then -- it failed prepping
+				origin.send(st.error_reply(stanza, "modify", "bad-request", "Invalid JID"))
+				return true
+			end
+			local _, _, resource = jid_split(qwith);
+			qwith = jid_bare(pwith);
+			qres = resource;
+		end
+
+		-- RSM stuff
+		local qmax = m_min(qset and qset.max or default_max_items, max_max_items);
+		local last;
+
+		local sql_query = ([[
+		SELECT `id`, `when`, `stanza`
+		FROM `prosodyarchive`
+		WHERE `host` = ? AND `user` = ? AND `store` = ?
+		AND `when` BETWEEN ? AND ?
+		%s %s
+		AND `id` > ?
+		LIMIT ?;
+		]]):format(qwith and [[AND `with` = ?]] or "", qres and [[AND `resource` = ?]] or "")
+
+		local p = {
+			host, origin.username, archive_store,
+			qstart or 0, qend or time_now(),
+			qset and tonumber(qset.after) or 0,
+			qmax
+		};
+		if qwith then
+			if qres then
+				t_insert(p, 6, qres);
+			end
+			t_insert(p, 6, qwith);
+		end
+		local data, err = getsql(sql_query, unpack(p));
+		if not data then
+			origin.send(st.error_reply(stanza, "cancel", "internal-server-error", "Error loading archive: "..tostring(err)));
+			return true
+		end
+
+		for item in data:rows() do
+			local id, when, orig_stanza = unpack(item);
+			--module:log("debug", "id is %s", id);
+
+			local fwd_st = st.message{ to = origin.full_jid }
+				:tag("result", { xmlns = xmlns_mam, queryid = qid, id = id }):up()
+				:tag("forwarded", { xmlns = xmlns_forward })
+					:tag("delay", { xmlns = xmlns_delay, stamp = timestamp(when) }):up();
+			orig_stanza = st.deserialize(deserialize(orig_stanza));
+			orig_stanza.attr.xmlns = "jabber:client";
+			fwd_st:add_child(orig_stanza);
+			origin.send(fwd_st);
+			last = id;
+		end
+		-- That's all folks!
+		module:log("debug", "Archive query %s completed", tostring(qid));
+
+		local reply = st.reply(stanza);
+		if last then
+			-- This is a bit redundant, isn't it?
+			reply:query(xmlns_mam):add_child(rsm.generate{last = last});
+		end
+		origin.send(reply);
+		return true
+	end
+end);
+
+local function has_in_roster(user, who)
+	local roster = rm_load_roster(user, host);
+	module:log("debug", "%s has %s in roster? %s", user, who, roster[who] and "yes" or "no");
+	return roster[who];
+end
+
+local function shall_store(user, who)
+	-- TODO Cache this?
+	local prefs = get_prefs(user);
+	local rule = prefs[who];
+	module:log("debug", "%s's rule for %s is %s", user, who, tostring(rule))
+	if rule ~= nil then
+		return rule;
+	else -- Below could be done by a metatable
+		local default = prefs[false];
+		module:log("debug", "%s's default rule is %s", user, tostring(default))
+		if default == nil then
+			default = global_default_policy;
+			module:log("debug", "Using global default rule, %s", tostring(default))
+		end
+		if default == "roster" then
+			return has_in_roster(user, who);
+		end
+		return default;
+	end
+end
+
+-- Handle messages
+local function message_handler(event, c2s)
+	local origin, stanza = event.origin, event.stanza;
+	local orig_type = stanza.attr.type or "normal";
+	local orig_to = stanza.attr.to;
+	local orig_from = stanza.attr.from;
+
+	if not orig_from and c2s then
+		orig_from = origin.full_jid;
+	end
+	orig_to = orig_to or orig_from; -- Weird corner cases
+
+	-- Don't store messages of these types
+	if orig_type == "error"
+	or orig_type == "headline"
+	or orig_type == "groupchat"
+	or not stanza:get_child("body") then
+		return;
+		-- TODO Maybe headlines should be configurable?
+	end
+
+	local store_user, store_host = jid_split(c2s and orig_from or orig_to);
+	local target_jid = c2s and orig_to or orig_from;
+	local target_bare = jid_bare(target_jid);
+	local _, _, target_resource = jid_split(target_jid);
+
+	if shall_store(store_user, target_bare) then
+		module:log("debug", "Archiving stanza: %s", stanza:top_tag());
+
+		--local id = uuid();
+		local when = time_now();
+		-- And stash it
+		local ok, err = setsql([[
+		INSERT INTO `prosodyarchive`
+		(`host`, `user`, `store`, `when`, `with`, `resource`, `stanza`)
+		VALUES (?, ?, ?, ?, ?, ?, ?);
+		]], store_host, store_user, archive_store, when, target_bare, target_resource, serialize(st.preserialize(stanza)))
+		if ok then
+			sql.commit();
+		else
+			module:log("error", "SQL error: %s", err);
+			sql.rollback();
+		end
+		--[[ This was dropped from the spec
+		if ok then 
+			stanza:tag("archived", { xmlns = xmlns_mam, by = host, id = id }):up();
+		end
+		--]]
+	else
+		module:log("debug", "Not archiving stanza: %s", stanza:top_tag());
+	end
+end
+
+local function c2s_message_handler(event)
+	return message_handler(event, true);
+end
+
+-- Stanzas sent by local clients
+module:hook("pre-message/bare", c2s_message_handler, 2);
+module:hook("pre-message/full", c2s_message_handler, 2);
+-- Stanszas to local clients
+module:hook("message/bare", message_handler, 2);
+module:hook("message/full", message_handler, 2);
+
+module:add_feature(xmlns_mam);
+
+-- In the telnet console, run:
+-- >hosts["this host"].modules.mam_sql.environment.create_sql()
+function create_sql()
+	local stm = getsql[[
+	CREATE TABLE `prosodyarchive` (
+		`host` TEXT,
+		`user` TEXT,
+		`store` TEXT,
+		`id` INTEGER PRIMARY KEY AUTOINCREMENT,
+		`when` INTEGER,
+		`with` TEXT,
+		`resource` TEXT,
+		`stanza` TEXT
+	);
+	CREATE INDEX `hus` ON `prosodyarchive` (`host`, `user`, `store`);
+	CREATE INDEX `with` ON `prosodyarchive` (`with`);
+	CREATE INDEX `thetime` ON `prosodyarchive` (`when`);
+	]];
+	stm:execute();
+	sql.commit();
+end