File

util/throttle.lua @ 8791:8da11142fabf

muc: Allow clients to change multiple affiliations or roles at once (#345) According to XEP-0045 sections 9.2, 9.5 and 9.8 affiliation lists and role lists should allow mass-modification. Prosody however would just use the first entry of the list and ignore the rest. This is fixed by introducing a `for` loop to `set` stanzas of the respective `muc#admin` namespace. In order for this loop to work, the error handling was changed a little. Prosody no longer returns after the first error. Instead, an error reply is sent for each malformed or otherwise wrong entry, but the loop keeps going over the other entries. This may lead to multiple error messages being sent for one client request. A notable exception from this is when the XML Schema for `muc#admin` requests is violated. In that case the loop is aborted with an error message to the client. The change is a bit bigger than that in order to have the loop only for `set` stanzas without changing the behaviour of the `get` stanzas. This is now more in line with trunk, where there are separate methods for each stanza type. References: #345
author Lennart Sauerbeck <devel@lennart.sauerbeck.org>
date Sat, 18 Mar 2017 18:47:28 +0100
parent 8272:64165865b131
child 8555:4f0f5b49bb03
line wrap: on
line source


local gettime = require "util.time".now
local setmetatable = setmetatable;

local _ENV = nil;

local throttle = {};
local throttle_mt = { __index = throttle };

function throttle:update()
	local newt = gettime();
	local elapsed = newt - self.t;
	self.t = newt;
	local balance = (self.rate * elapsed) + self.balance;
	if balance > self.max then
		self.balance = self.max;
	else
		self.balance = balance;
	end
	return self.balance;
end

function throttle:peek(cost)
	cost = cost or 1;
	return self.balance >= cost or self:update() >= cost;
end

function throttle:poll(cost, split)
	if self:peek(cost) then
		self.balance = self.balance - cost;
		return true;
	else
		local balance = self.balance;
		if split then
			self.balance = 0;
		end
		return false, balance, (cost-balance);
	end
end

local function create(max, period)
	return setmetatable({ rate = max / period, max = max, t = gettime(), balance = max }, throttle_mt);
end

return {
	create = create;
};