File

mod_ogp/mod_ogp.lua @ 4542:fb4a50bf60f1

mod_prometheus: Invoke stats collection if in 'manual' mode Since 10d13e0554f9 a special value for statistics_interval "manual" exists, where a module is expected to invoke processing in connection to collection of stats. This makes internal collection and exporting to Prometheus happens at the same time with no chance of timers getting out of sync.
author Kim Alvefur <zash@zash.se>
date Tue, 13 Apr 2021 23:53:53 +0200
parent 4504:0136c98f574c
child 4598:09f0911c735d
line wrap: on
line source

local mod_muc = module:depends("muc")
local http = require "net.http"
local st = require "util.stanza"
local url_pattern = [[https?://%S+]]
local domain_pattern = '^%w+://([^/]+)'
local xmlns_fasten = "urn:xmpp:fasten:0"
local xmlns_xhtml = "http://www.w3.org/1999/xhtml"
local whitelist = module:get_option_set("ogp_domain_whitelist", {})


local function is_whitelisted(url)
	if whitelist:empty() then
		return true
	end
	local domain = url:match(domain_pattern)
	if whitelist:contains(domain) then
		return true;
	end
	return false
end


local function fetch_ogp_data(room, url, origin_id)
	if not url or not is_whitelisted(url) then
		return;
	end

	http.request(
		url,
		nil,
		function(response_body, response_code, _)
			if response_code ~= 200 then
				module:log("debug", "Call to %s returned code %s and body %s", url, response_code, response_body)
				return
			end

			local to = room.jid
			local from = room and room.jid or module.host
			local fastening = st.message({to = to, from = from, type = 'groupchat'}):tag("apply-to", {xmlns = xmlns_fasten, id = origin_id})
			local found_metadata = false
			local message_body = ""

			local meta_pattern = [[<meta (.-)/?>]]
			for match in response_body:gmatch(meta_pattern) do
				local property = match:match([[property=%s*["']?(og:.-)["']?%s]])
				if not property then
					property = match:match([[property=["']?(og:.-)["']$]])
				end

				local content = match:match([[content=%s*["'](.-)["']%s]])
				if not content then
					content = match:match([[content=["']?(.-)["']$]])
				end
				if not content then
					content = match:match([[content=(.-) property]])
				end
				if not content then
					content = match:match([[content=(.-)$]])
				end

				if property and content then
					module:log("debug", property .. "\t" .. content)
					fastening:tag(
						"meta",
						{
							xmlns = xmlns_xhtml,
							property = property,
							content = content
						}
					):up()
					found_metadata = true
					message_body = message_body .. property .. "\t" .. content .. "\n"
				end
			end

			if found_metadata then
				mod_muc.get_room_from_jid(room.jid):broadcast_message(fastening)
			end
			module:log("debug", tostring(fastening))
		end
	)
end

local function ogp_handler(event)
	local room, stanza = event.room, st.clone(event.stanza)
	local body = stanza:get_child_text("body")

	if not body then return; end

	local origin_id = stanza:find("{urn:xmpp:sid:0}origin-id@id")
	if not origin_id then return; end

	for url in body:gmatch(url_pattern) do
		fetch_ogp_data(room, url, origin_id);
	end
end

module:hook("muc-occupant-groupchat", ogp_handler)


module:hook("muc-message-is-historic", function (event)
	local fastening = event.stanza:get_child('apply-to', xmlns_fasten)
	if fastening and fastening:get_child('meta', xmlns_xhtml) then
		return true
	end
end);