File

util/throttle.lua @ 9089:3a7a0b9f42f3

util.dataforms: Skip all fields for the 'cancel' form type XEP-0004 says: > a data form of type "cancel" SHOULD NOT contain any <field/> elements. The title and instructions don't seem to be of much value in this case either. I'm not aware of 'cancel' being used anywhere, so this should break nothing. Early return is always nice.
author Kim Alvefur <zash@zash.se>
date Fri, 03 Aug 2018 21:06:59 +0200
parent 8555:4f0f5b49bb03
child 12975:d10957394a3c
line wrap: on
line source


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

local _ENV = nil;
-- luacheck: std none

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;
};