mod_http_oauth2: Use more compact IDs UUIDs are nice but so verbose! The reduction in entropy for the nonce should be fine since the timestamp is also counts towards this, and it changes every second (modulo clock shenanigans), so the chances of someone managing to get the same client_secret by registering with the same information at the same time as another entity should be negligible.

local base64_encode = require"util.encodings".base64.encode;
local random_bytes = require"util.random".bytes;

local b64url = { ["+"] = "-", ["/"] = "_", ["="] = "" };
local function random_resource()
	return base64_encode(random_bytes(8)):gsub("[+/=]", b64url);
end

module:hook("pre-resource-bind", function (event)
	event.resource = random_resource();
end);