mod_muc_limits: Reduce cost of multi-line messages, make configurable
Typing a 5-line message preceded by a few chat states would have hit the
default limit.
--- a/mod_muc_limits/README.markdown Fri Jul 14 16:20:54 2023 +0200
+++ b/mod_muc_limits/README.markdown Sat Jul 15 09:09:41 2023 +0200
@@ -35,13 +35,15 @@
You can define (globally or per-MUC component) the following options:
- Name Default value Description
- --------------------- --------------- --------------------------------------------------
- muc_event_rate 0.5 The maximum number of events per second.
- muc_burst_factor 6 Allow temporary bursts of this multiple.
- muc_max_nick_length 23 The maximum allowed length of user nicknames
- muc_max_char_count 5664 The maximum allowed number of bytes in a message
- muc_max_line_count 23 The maximum allowed number of lines in a message
+ Name Default value Description
+ --------------------------- --------------- ----------------------------------------------------------
+ muc_event_rate 0.5 The maximum number of events per second.
+ muc_burst_factor 6 Allow temporary bursts of this multiple.
+ muc_max_nick_length 23 The maximum allowed length of user nicknames
+ muc_max_char_count 5664 The maximum allowed number of bytes in a message
+ muc_max_line_count 23 The maximum allowed number of lines in a message
+ muc_limit_base_cost 1 Base cost of sending a stanza
+ muc_line_count_multiplier 0.1 Additional cost of each newline in the body of a message
For more understanding of how these values are used, see the algorithm
section below.
--- a/mod_muc_limits/mod_muc_limits.lua Fri Jul 14 16:20:54 2023 +0200
+++ b/mod_muc_limits/mod_muc_limits.lua Sat Jul 15 09:09:41 2023 +0200
@@ -15,6 +15,8 @@
local max_nick_length = module:get_option_number("muc_max_nick_length", 23); -- Default chosen through scientific methods
local max_line_count = module:get_option_number("muc_max_line_count", 23); -- Default chosen through s/scientific methods/copy and paste/
local max_char_count = module:get_option_number("muc_max_char_count", 5664); -- Default chosen by multiplying a number by 23
+local base_cost = math.max(module:get_option_number("muc_limit_base_cost", 1), 0);
+local line_multiplier = math.max(module:get_option_number("muc_line_count_multiplier", 0.1), 0);
local join_only = module:get_option_boolean("muc_limit_joins_only", false);
local dropped_count = 0;
@@ -49,7 +51,7 @@
throttle = new_throttle(period*burst, burst);
room.throttle = throttle;
end
- local cost = 1;
+ local cost = base_cost;
local body = stanza:get_child_text("body");
if body then
-- TODO calculate a text diagonal cross-section or some mathemagical
@@ -65,7 +67,7 @@
:tag("x", { xmlns = xmlns_muc; }));
return true;
end
- cost = cost + body_lines;
+ cost = cost + (body_lines * line_multiplier);
end
if not throttle:poll(cost) then
module:log("debug", "Dropping stanza for %s@%s from %s, over rate limit", dest_room, dest_host, from_jid);