Add last_login field to auth.txt

Also shortens some related code and adds more parameters to string.split.

builtin/game/auth.lua

@@ -41,12 +41,14 @@ local function read_auth_file()
 	end
 	for line in file:lines() do
 		if line ~= "" then
-			local name, password, privilegestring = string.match(line, "([^:]*):([^:]*):([^:]*)")
-			if not name or not password or not privilegestring then
+			local fields = line:split(":", true)
+			local name, password, privilege_string, last_login = unpack(fields)
+			last_login = tonumber(last_login)
+			if not (name and password and privilege_string) then
 				error("Invalid line in auth.txt: "..dump(line))
 			end
-			local privileges = core.string_to_privs(privilegestring)
-			newtable[name] = {password=password, privileges=privileges}
+			local privileges = core.string_to_privs(privilege_string)
+			newtable[name] = {password=password, privileges=privileges, last_login=last_login}
 		end
 	end
 	io.close(file)
@@ -63,14 +65,16 @@ local function save_auth_file()
 		assert(type(stuff) == "table")
 		assert(type(stuff.password) == "string")
 		assert(type(stuff.privileges) == "table")
+		assert(stuff.last_login == nil or type(stuff.last_login) == "number")
 	end
 	local file, errmsg = io.open(core.auth_file_path, 'w+b')
 	if not file then
 		error(core.auth_file_path.." could not be opened for writing: "..errmsg)
 	end
 	for name, stuff in pairs(core.auth_table) do
-		local privstring = core.privs_to_string(stuff.privileges)
-		file:write(name..":"..stuff.password..":"..privstring..'\n')
+		local priv_string = core.privs_to_string(stuff.privileges)
+		local parts = {name, stuff.password, priv_string, stuff.last_login or ""}
+		file:write(table.concat(parts, ":").."\n")
 	end
 	io.close(file)
 end
@@ -111,6 +115,8 @@ core.builtin_auth_handler = {
 		return {
 			password = core.auth_table[name].password,
 			privileges = privileges,
+			-- Is set to nil if unknown
+			last_login = core.auth_table[name].last_login,
 		}
 	end,
 	create_auth = function(name, password)
@@ -120,6 +126,7 @@ core.builtin_auth_handler = {
 		core.auth_table[name] = {
 			password = password,
 			privileges = core.string_to_privs(core.setting_get("default_privs")),
+			last_login = os.time(),
 		}
 		save_auth_file()
 	end,
@@ -139,7 +146,9 @@ core.builtin_auth_handler = {
 		assert(type(name) == "string")
 		assert(type(privileges) == "table")
 		if not core.auth_table[name] then
-			core.builtin_auth_handler.create_auth(name, core.get_password_hash(name, core.setting_get("default_password")))
+			core.builtin_auth_handler.create_auth(name,
+				core.get_password_hash(name,
+					core.setting_get("default_password")))
 		end
 		core.auth_table[name].privileges = privileges
 		core.notify_authentication_modified(name)
@@ -149,6 +158,11 @@ core.builtin_auth_handler = {
 		read_auth_file()
 		return true
 	end,
+	record_login = function(name)
+		assert(type(name) == "string")
+		assert(core.auth_table[name]).last_login = os.time()
+		save_auth_file()
+	end,
 }
 
 function core.register_authentication_handler(handler)
@@ -160,29 +174,27 @@ function core.register_authentication_handler(handler)
 end
 
 function core.get_auth_handler()
-	if core.registered_auth_handler then
-		return core.registered_auth_handler
-	end
-	return core.builtin_auth_handler
+	return core.registered_auth_handler or core.builtin_auth_handler
 end
 
-function core.set_player_password(name, password)
-	if core.get_auth_handler().set_password then
-		core.get_auth_handler().set_password(name, password)
+local function auth_pass(name)
+	return function(...)
+		local auth_handler = core.get_auth_handler()
+		if auth_handler[name] then
+			return auth_handler[name](...)
+		end
+		return false
 	end
 end
 
-function core.set_player_privs(name, privs)
-	if core.get_auth_handler().set_privileges then
-		core.get_auth_handler().set_privileges(name, privs)
-	end
-end
-
-function core.auth_reload()
-	if core.get_auth_handler().reload then
-		return core.get_auth_handler().reload()
-	end
-	return false
-end
+core.set_player_password = auth_pass("set_password")
+core.set_player_privs    = auth_pass("set_privileges")
+core.auth_reload         = auth_pass("reload")
 
 
+local record_login = auth_pass("record_login")
+
+core.register_on_joinplayer(function(player)
+	record_login(player:get_player_name())
+end)
+

builtin/game/chatcommands.lua

@@ -723,3 +723,20 @@ core.register_chatcommand("msg", {
 	end,
 })
 
+core.register_chatcommand("last-login", {
+	params = "[name]",
+	description = "Get the last login time of a player",
+	func = function(name, param)
+		if param == "" then
+			param = name
+		end
+		local pauth = core.get_auth_handler().get_auth(param)
+		if pauth and pauth.last_login then
+			-- Time in UTC, ISO 8601 format
+			return true, "Last login time was " ..
+				os.date("!%Y-%m-%dT%H:%M:%SZ", pauth.last_login)
+		end
+		return false, "Last login time is unknown"
+	end,
+})
+