File

util/id.lua @ 13146:771eb453e03a

util.sqlite3: Deduplicate query methods There were 3 very similar methods: - :execute() - :execute_query() - :execute_update() The first one returns the prepared statement and is mainly used internally in the library for CREATE statements. The later two only really differ in how the results are returned. Those two are one main method and one small one that only picks out the iterator.
author Kim Alvefur <zash@zash.se>
date Sat, 10 Jun 2023 22:02:15 +0200
parent 12975:d10957394a3c
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-- Prosody IM
-- Copyright (C) 2008-2017 Matthew Wild
-- Copyright (C) 2008-2017 Waqas Hussain
-- Copyright (C) 2008-2017 Kim Alvefur
--
-- This project is MIT/X11 licensed. Please see the
-- COPYING file in the source package for more information.
--

local s_gsub = string.gsub;
local random_bytes = require "prosody.util.random".bytes;
local base64_encode = require "prosody.util.encodings".base64.encode;

local b64url = { ["+"] = "-", ["/"] = "_", ["="] = "" };
local function b64url_random(len)
	return (s_gsub(base64_encode(random_bytes(len)), "[+/=]", b64url));
end

return {
	-- sizes divisible by 3 fit nicely into base64 without padding==

	-- for short lived things with low risk of collisions
	tiny = function() return b64url_random(3); end;

	-- close to 8 bytes, should be good enough for relatively short lived or uses
	-- scoped by host or users, half the size of an uuid
	short = function() return b64url_random(9); end;

	-- more entropy than uuid at 2/3 the size
	-- should be okay for globally scoped ids or security token
	medium = function() return b64url_random(18); end;

	-- as long as an uuid but MOAR entropy
	long = function() return b64url_random(27); end;

	-- pick your own adventure
	custom = function (size)
		return function () return b64url_random(size); end;
	end;
}