Purge the roster from RAM when the user logs off.
Also.. the `download` flag was being checked for, but never set, causing the
roster to be fetched even if it was cached.
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);