File

+
−local mod_muc = module:depends("muc")
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−local http = require "net.http"
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−local st = require "util.stanza"
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−local url_pattern = [[https?://%S+]]
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−local domain_pattern = '^%w+://([^/]+)'
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−local xmlns_fasten = "urn:xmpp:fasten:0"
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−local xmlns_xhtml = "http://www.w3.org/1999/xhtml"
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−local allowlist = module:get_option_set("ogp_domain_allowlist", module:get_option_set("ogp_domain_whitelist", {}))
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−local denylist = module:get_option_set("ogp_domain_denylist", {})
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−
+
−
+
−local function is_allowed(domain)
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−	if allowlist:empty() then
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−		return true
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−	end
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−	if allowlist:contains(domain) then
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−		return true
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−	end
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−	return false
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−end
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−
+
−local function is_denied(domain)
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−	if denylist:empty() then
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−		return false
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−	end
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−	if denylist:contains(domain) then
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−		return true
+
−	end
+
−	return false
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−end
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−
+
−
+
−local function fetch_ogp_data(room, url, origin_id)
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−	if not url then
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−		return;
+
−	end
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−
+
−	local domain = url:match(domain_pattern);
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−	if is_denied(domain) or not is_allowed(domain) then
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−		return;
+
−	end
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−
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−	http.request(
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−		url,
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−		nil,
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−		function(response_body, response_code, _)
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−			if response_code ~= 200 then
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−				module:log("debug", "Call to %s returned code %s and body %s", url, response_code, response_body)
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−				return
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−			end
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−
+
−			local to = room.jid
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−			local from = room and room.jid or module.host
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−			local fastening = st.message({to = to, from = from, type = 'groupchat'}):tag("apply-to", {xmlns = xmlns_fasten, id = origin_id})
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−			local found_metadata = false
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−			local message_body = ""
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−
+
−			local meta_pattern = [[<meta (.-)/?>]]
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−			for match in response_body:gmatch(meta_pattern) do
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−				local property = match:match([[property=%s*["']?(og:.-)["']?%s]])
+
−				if not property then
+
−					property = match:match([[property=["']?(og:.-)["']$]])
+
−				end
+
−
+
−				local content = match:match([[content=%s*["'](.-)["']%s]])
+
−				if not content then
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−					content = match:match([[content=["']?(.-)["']$]])
+
−				end
+
−				if not content then
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−					content = match:match([[content=(.-) property]])
+
−				end
+
−				if not content then
+
−					content = match:match([[content=(.-)$]])
+
−				end
+
−
+
−				if property and content then
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−					module:log("debug", property .. "\t" .. content)
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−					fastening:tag(
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−						"meta",
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−						{
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−							xmlns = xmlns_xhtml,
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−							property = property,
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−							content = content
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−						}
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−					):up()
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−					found_metadata = true
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−					message_body = message_body .. property .. "\t" .. content .. "\n"
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−				end
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−			end
+
−
+
−			if found_metadata then
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−				mod_muc.get_room_from_jid(room.jid):broadcast_message(fastening)
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−			end
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−			module:log("debug", tostring(fastening))
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−		end
+
−	)
+
−end
+
−
+
−local function ogp_handler(event)
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−	local room, stanza = event.room, st.clone(event.stanza)
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−	local body = stanza:get_child_text("body")
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−
+
−	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
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−		fetch_ogp_data(room, url, origin_id);
+
−	end
+
−end
+
−
+
−module:hook("muc-occupant-groupchat", ogp_handler)
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−
+
−
+
−module:hook("muc-message-is-historic", function (event)
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−	local fastening = event.stanza:get_child('apply-to', xmlns_fasten)
+
−	if fastening and fastening:get_child('meta', xmlns_xhtml) then
+
−		return true
+
−	end
+
−end);