view mod_auto156/mod_auto156.lua @ 4976:75b6e5df65f9

various: Improve error reporting if missing file server module on 0.12 If there is some error loading net.http.files then it would be swallowed by the pcall and then it would proceed to trying mod_http_files, which might cause unexpected behavior on 0.12 Ref #1765
author Kim Alvefur <zash@zash.se>
date Mon, 18 Jul 2022 22:47:54 +0200
parents 5d494dba9c02
children
line wrap: on
line source

-- Synthesize XEP-0156 JSON from DNS
local array = require "util.array";
local encodings = require "util.encodings";
local json = require "util.json";
local promise = require "util.promise";

local dns = require"net.adns".resolver();

local function check_dns(domain)
	return dns:lookup_promise("_xmppconnect." .. domain, "TXT");
end

local function check_domain(domain)
	return promise.resolve(domain):next(encodings.stringprep.nameprep):next(encodings.idna.to_ascii):next(
		function(domain_A)
			if not domain_A then
				return promise.reject(400);
			else
				return domain_A;
			end
		end):next(check_dns):next(function(txt)
		local uris = array();
		for _, cm in ipairs(txt) do
			local kind, uri = tostring(cm.txt):match("^_xmpp%-client%-(%w+)=([hpstw]+s?://.*)");
			if kind then
				uris:push({rel = "urn:xmpp:alt-connections:" .. kind, href = uri});
			end
		end
		if #uris == 0 then
			return promise.reject(404);
		end
		return {links=uris};
	end);
end

module:depends("http");
module:provides("http", {
	route = {
		["GET /*"] = function(_, domain)
			return check_domain(domain):next(function(altmethods)
				return {headers = {content_type = "application/json"}, body = json.encode(altmethods)};
			end);
		end,
	},
});

function module.command(args)
	local async = require "util.async";
	for _, domain in ipairs(args) do
		print(assert(async.wait_for(check_domain(domain):next(json.encode))));
	end
end