plugins/mod_pubsub/pubsub.lib.lua
author Kim Alvefur <zash@zash.se>
Tue, 14 May 2024 17:07:47 +0200
changeset 13494 6f840763fc73
parent 13490 fdd1438d9ef7
permissions -rw-r--r--
net.server_epoll: Add support for systemd socket activation Allows creating listening sockets and accepting client connections before Prosody starts. This is unlike normal Prosody dynamic resource management, where ports may added and removed at any time, and the ports defined by the config. Weird things happen if these are closed (e.g. due to reload) so here we prevent closing and ensure sockets are reused when opened again.

local t_unpack = table.unpack;
local time_now = os.time;

local jid_prep = require "prosody.util.jid".prep;
local set = require "prosody.util.set";
local st = require "prosody.util.stanza";
local it = require "prosody.util.iterators";
local uuid_generate = require "prosody.util.uuid".generate;
local dataform = require"prosody.util.dataforms".new;
local errors = require "prosody.util.error";

local xmlns_pubsub = "http://jabber.org/protocol/pubsub";
local xmlns_pubsub_errors = "http://jabber.org/protocol/pubsub#errors";
local xmlns_pubsub_owner = "http://jabber.org/protocol/pubsub#owner";

local _M = {};

local handlers = {};
_M.handlers = handlers;

local pubsub_errors = {
	["conflict"] = { "cancel", "conflict" };
	["invalid-jid"] = { "modify", "bad-request", nil, "invalid-jid" };
	["jid-required"] = { "modify", "bad-request", nil, "jid-required" };
	["nodeid-required"] = { "modify", "bad-request", nil, "nodeid-required" };
	["item-not-found"] = { "cancel", "item-not-found" };
	["not-subscribed"] = { "modify", "unexpected-request", nil, "not-subscribed" };
	["invalid-options"] = { "modify", "bad-request", nil, "invalid-options" };
	["forbidden"] = { "auth", "forbidden" };
	["not-allowed"] = { "cancel", "not-allowed" };
	["not-acceptable"] = { "modify", "not-acceptable" };
	["internal-server-error"] = { "wait", "internal-server-error" };
	["precondition-not-met"] = { "cancel", "conflict", nil, "precondition-not-met" };
	["invalid-item"] = { "modify", "bad-request", "invalid item" };
	["persistent-items-unsupported"] = { "cancel", "feature-not-implemented", nil, "persistent-items" };
};
local function pubsub_error_reply(stanza, error)
	local e = pubsub_errors[error];
	if not e and errors.is_err(error) then
		e = { error.type, error.condition, error.text, error.pubsub_condition };
	end
	local reply = st.error_reply(stanza, t_unpack(e, 1, 3));
	if e[4] then
		reply:tag(e[4], { xmlns = xmlns_pubsub_errors }):up();
	end
	return reply;
end
_M.pubsub_error_reply = pubsub_error_reply;

local function dataform_error_message(err) -- ({ string : string }) -> string?
	local out = {};
	for field, errmsg in pairs(err) do
		table.insert(out, ("%s: %s"):format(field, errmsg))
	end
	return table.concat(out, "; ");
end

-- Note: If any config options are added that are of complex types,
-- (not simply strings/numbers) then the publish-options code will
-- need to be revisited
local node_config_form = dataform {
	{
		type = "hidden";
		var = "FORM_TYPE";
		value = "http://jabber.org/protocol/pubsub#node_config";
	};
	{
		type = "text-single";
		name = "title";
		var = "pubsub#title";
		label = "Title";
	};
	{
		type = "text-single";
		name = "description";
		var = "pubsub#description";
		label = "Description";
	};
	{
		type = "text-single";
		name = "payload_type";
		var = "pubsub#type";
		label = "The type of node data, usually specified by the namespace of the payload (if any)";
	};
	{
		type = "text-single";
		datatype = "pubsub:integer-or-max";
		name = "max_items";
		range_min = 1;
		var = "pubsub#max_items";
		label = "Max # of items to persist";
	};
	{
		type = "boolean";
		name = "persist_items";
		var = "pubsub#persist_items";
		label = "Persist items to storage";
	};
	{
		type = "list-single";
		name = "access_model";
		var = "pubsub#access_model";
		label = "Specify the subscriber model";
		options = {
			"authorize",
			"open",
			"presence",
			"roster",
			"whitelist",
		};
	};
	{
		type = "list-multi"; -- TODO some way to inject options
		name = "roster_groups_allowed";
		var = "pubsub#roster_groups_allowed";
		label = "Roster groups allowed to subscribe";
	};
	{
		type = "list-single";
		name = "publish_model";
		var = "pubsub#publish_model";
		label = "Specify the publisher model";
		options = {
			"publishers";
			"subscribers";
			"open";
		};
	};
	{
		type = "list-single";
		var = "pubsub#send_last_published_item";
		name = "send_last_published_item";
		options = { "never"; "on_sub"; "on_sub_and_presence" };
	};
	{
		type = "boolean";
		value = true;
		label = "Whether to deliver event notifications";
		name = "notify_items";
		var = "pubsub#deliver_notifications";
	};
	{
		type = "boolean";
		value = true;
		label = "Whether to deliver payloads with event notifications";
		name = "include_payload";
		var = "pubsub#deliver_payloads";
	};
	{
		type = "list-single";
		name = "notification_type";
		var = "pubsub#notification_type";
		label = "Specify the delivery style for notifications";
		options = {
			{ label = "Messages of type normal", value = "normal" },
			{ label = "Messages of type headline", value = "headline", default = true },
		};
	};
	{
		type = "boolean";
		label = "Whether to notify subscribers when the node is deleted";
		name = "notify_delete";
		var = "pubsub#notify_delete";
		value = true;
	};
	{
		type = "boolean";
		label = "Whether to notify subscribers when items are removed from the node";
		name = "notify_retract";
		var = "pubsub#notify_retract";
		value = true;
	};
	{
		type = "list-single";
		label = "Specify whose JID to include as the publisher of items";
		name = "itemreply";
		var = "pubsub#itemreply";
		options = {
			{ label = "Include the node owner's JID", value = "owner" };
			{ label = "Include the item publisher's JID", value = "publisher" };
			{ label = "Don't include any JID with items", value = "none", default = true };
		};
	};
};
_M.node_config_form = node_config_form;

local subscribe_options_form = dataform {
	{
		type = "hidden";
		var = "FORM_TYPE";
		value = "http://jabber.org/protocol/pubsub#subscribe_options";
	};
	{
		type = "boolean";
		name = "pubsub#include_body";
		label = "Receive message body in addition to payload?";
	};
};
_M.subscribe_options_form = subscribe_options_form;

local node_metadata_form = dataform {
	{
		type = "hidden";
		var = "FORM_TYPE";
		value = "http://jabber.org/protocol/pubsub#meta-data";
	};
	{
		type = "text-single";
		name = "pubsub#title";
	};
	{
		type = "text-single";
		name = "pubsub#description";
	};
	{
		type = "text-single";
		name = "pubsub#type";
	};
	{
		type = "text-single";
		name = "pubsub#access_model";
	};
	{
		type = "text-single";
		name = "pubsub#publish_model";
	};
};
_M.node_metadata_form = node_metadata_form;

local service_method_feature_map = {
	add_subscription = { "subscribe", "subscription-options" };
	create = { "create-nodes", "instant-nodes", "item-ids", "create-and-configure" };
	delete = { "delete-nodes" };
	get_items = { "retrieve-items" };
	get_subscriptions = { "retrieve-subscriptions" };
	node_defaults = { "retrieve-default" };
	publish = { "publish", "multi-items", "publish-options" };
	purge = { "purge-nodes" };
	retract = { "delete-items", "retract-items" };
	set_node_config = { "config-node", "meta-data" };
	set_affiliation = { "modify-affiliations" };
};
local service_config_feature_map = {
	autocreate_on_publish = { "auto-create" };
};

function _M.get_feature_set(service)
	local supported_features = set.new();

	for method, features in pairs(service_method_feature_map) do
		if service[method] then
			for _, feature in ipairs(features) do
				if feature then
					supported_features:add(feature);
				end
			end
		end
	end

	for option, features in pairs(service_config_feature_map) do
		if service.config[option] then
			for _, feature in ipairs(features) do
				if feature then
					supported_features:add(feature);
				end
			end
		end
	end

	for affiliation in pairs(service.config.capabilities) do
		if affiliation ~= "none" and affiliation ~= "owner" then
			supported_features:add(affiliation.."-affiliation");
		end
	end

	if service.node_defaults.access_model then
		supported_features:add("access-"..service.node_defaults.access_model);
	end

	if service.node_defaults.send_last_published_item ~= "never" then
		supported_features:add("last-published");
	end

	if rawget(service.config, "itemstore") and rawget(service.config, "nodestore") then
		supported_features:add("persistent-items");
	end

	if true --[[ node_metadata_form[max_items].datatype == "pubsub:integer-or-max" ]] then
		supported_features:add("config-node-max");
	end

	return supported_features;
end

function _M.handle_disco_info_node(event, service)
	local stanza, reply, node = event.stanza, event.reply, event.node;
	local ok, ret = service:get_nodes(stanza.attr.from);
	if not ok then
		event.origin.send(pubsub_error_reply(stanza, ret));
		return true;
	end
	local node_obj = ret[node];
	if not node_obj then
		event.origin.send(pubsub_error_reply(stanza, "item-not-found"));
		return true;
	end
	event.exists = true;
	reply:tag("identity", { category = "pubsub", type = "leaf" }):up();
	if node_obj.config then
		reply:add_child(node_metadata_form:form({
			["pubsub#title"] = node_obj.config.title;
			["pubsub#description"] = node_obj.config.description;
			["pubsub#type"] = node_obj.config.payload_type;
			["pubsub#access_model"] = node_obj.config.access_model;
			["pubsub#publish_model"] = node_obj.config.publish_model;
		}, "result"));
	end
end

function _M.handle_disco_items_node(event, service)
	local stanza, reply, node = event.stanza, event.reply, event.node;
	local ok, ret = service:get_items(node, stanza.attr.from);
	if not ok then
		event.origin.send(pubsub_error_reply(stanza, ret));
		return true;
	end

	for _, id in ipairs(ret) do
		reply:tag("item", { jid = service.config.jid or module.host, name = id }):up();
	end
	event.exists = true;
end

function _M.handle_pubsub_iq(event, service)
	local origin, stanza = event.origin, event.stanza;
	local pubsub_tag = stanza.tags[1];
	local action = pubsub_tag.tags[1];
	if not action then
		return origin.send(st.error_reply(stanza, "cancel", "bad-request"));
	end
	local prefix = "";
	if pubsub_tag.attr.xmlns == xmlns_pubsub_owner then
		prefix = "owner_";
	end
	local handler = handlers[prefix..stanza.attr.type.."_"..action.name];
	if handler then
		handler(origin, stanza, action, service);
		return true;
	end
end

function handlers.get_items(origin, stanza, items, service)
	local node = items.attr.node;

	local requested_items = {};
	for item in items:childtags("item") do
		table.insert(requested_items, item.attr.id);
	end
	if requested_items[1] == nil then
		requested_items = nil;
	end

	if not node then
		origin.send(pubsub_error_reply(stanza, "nodeid-required"));
		return true;
	end

	local node_obj = service.nodes[node];
	if not node_obj then
		origin.send(pubsub_error_reply(stanza, "item-not-found"));
		return true;
	end

	local resultspec; -- TODO rsm.get()
	if items.attr.max_items then
		resultspec = { max = tonumber(items.attr.max_items) };
	end
	local ok, results = service:get_items(node, stanza.attr.from, requested_items, resultspec);
	if not ok then
		origin.send(pubsub_error_reply(stanza, results));
		return true;
	end

	local expose_publisher = service.config.expose_publisher;
	if expose_publisher == nil and node_obj.config.itemreply == "publisher" then
		expose_publisher = true;
	end

	local data = st.stanza("items", { node = node });
	local iter, v, i = ipairs(results);
	if not requested_items then
		-- XXX Hack to preserve order of explicitly requested items.
		iter, v, i = it.reverse(iter, v, i);
	end

	for _, id in iter, v, i do
		local item = results[id];
		if not expose_publisher then
			item = st.clone(item);
			item.attr.publisher = nil;
		end
		data:add_child(item);
	end
	local reply = st.reply(stanza)
		:tag("pubsub", { xmlns = xmlns_pubsub })
			:add_child(data);
	origin.send(reply);
	return true;
end

function handlers.get_subscriptions(origin, stanza, subscriptions, service)
	local node = subscriptions.attr.node;
	local ok, ret = service:get_subscriptions(node, stanza.attr.from, stanza.attr.from);
	if not ok then
		origin.send(pubsub_error_reply(stanza, ret));
		return true;
	end
	local reply = st.reply(stanza)
		:tag("pubsub", { xmlns = xmlns_pubsub })
			:tag("subscriptions");
	for _, sub in ipairs(ret) do
		reply:tag("subscription", { node = sub.node, jid = sub.jid, subscription = 'subscribed' }):up();
	end
	origin.send(reply);
	return true;
end

function handlers.owner_get_subscriptions(origin, stanza, subscriptions, service)
	local node = subscriptions.attr.node;
	local ok, ret = service:get_subscriptions(node, stanza.attr.from);
	if not ok then
		origin.send(pubsub_error_reply(stanza, ret));
		return true;
	end
	local reply = st.reply(stanza)
		:tag("pubsub", { xmlns = xmlns_pubsub_owner })
			:tag("subscriptions");
	for _, sub in ipairs(ret) do
		reply:tag("subscription", { node = sub.node, jid = sub.jid, subscription = 'subscribed' }):up();
	end
	origin.send(reply);
	return true;
end

function handlers.owner_set_subscriptions(origin, stanza, subscriptions, service)
	local node = subscriptions.attr.node;
	if not node then
		origin.send(pubsub_error_reply(stanza, "nodeid-required"));
		return true;
	end
	if not service:may(node, stanza.attr.from, "subscribe_other") then
		origin.send(pubsub_error_reply(stanza, "forbidden"));
		return true;
	end

	local node_obj = service.nodes[node];
	if not node_obj then
		origin.send(pubsub_error_reply(stanza, "item-not-found"));
		return true;
	end

	for subscription_tag in subscriptions:childtags("subscription") do
		if subscription_tag.attr.subscription == 'subscribed' then
			local ok, err = service:add_subscription(node, stanza.attr.from, subscription_tag.attr.jid);
			if not ok then
				origin.send(pubsub_error_reply(stanza, err));
				return true;
			end
		elseif subscription_tag.attr.subscription == 'none' then
			local ok, err = service:remove_subscription(node, stanza.attr.from, subscription_tag.attr.jid);
			if not ok then
				origin.send(pubsub_error_reply(stanza, err));
				return true;
			end
		end
	end

	local reply = st.reply(stanza);
	origin.send(reply);
	return true;
end

function handlers.set_create(origin, stanza, create, service)
	local node = create.attr.node;
	local ok, ret, reply;
	local config;
	local configure = stanza.tags[1]:get_child("configure");
	if configure then
		local config_form = configure:get_child("x", "jabber:x:data");
		if not config_form then
			origin.send(st.error_reply(stanza, "modify", "bad-request", "Missing dataform"));
			return true;
		end
		local form_data, err = node_config_form:data(config_form);
		if err then
			origin.send(st.error_reply(stanza, "modify", "bad-request", dataform_error_message(err)));
			return true;
		end
		config = form_data;
	end
	if node then
		ok, ret = service:create(node, stanza.attr.from, config);
		if ok then
			reply = st.reply(stanza);
		else
			reply = pubsub_error_reply(stanza, ret);
		end
	else
		repeat
			node = uuid_generate();
			ok, ret = service:create(node, stanza.attr.from, config);
		until ok or ret ~= "conflict";
		if ok then
			reply = st.reply(stanza)
				:tag("pubsub", { xmlns = xmlns_pubsub })
					:tag("create", { node = node });
		else
			reply = pubsub_error_reply(stanza, ret);
		end
	end
	origin.send(reply);
	return true;
end

function handlers.owner_set_delete(origin, stanza, delete, service)
	local node = delete.attr.node;

	local reply;
	if not node then
		origin.send(pubsub_error_reply(stanza, "nodeid-required"));
		return true;
	end
	local ok, ret = service:delete(node, stanza.attr.from);
	if ok then
		reply = st.reply(stanza);
	else
		reply = pubsub_error_reply(stanza, ret);
	end
	origin.send(reply);
	return true;
end

function handlers.set_subscribe(origin, stanza, subscribe, service)
	local node, jid = subscribe.attr.node, subscribe.attr.jid;
	jid = jid_prep(jid);
	if not (node and jid) then
		origin.send(pubsub_error_reply(stanza, jid and "nodeid-required" or "invalid-jid"));
		return true;
	end
	local options_tag, options = stanza.tags[1]:get_child("options"), nil;
	if options_tag then
		-- FIXME form parsing errors ignored here, why?
		local err
		options, err = subscribe_options_form:data(options_tag.tags[1]);
		if err then
			origin.send(st.error_reply(stanza, "modify", "bad-request", dataform_error_message(err)));
			return true
		end
	end
	local ok, ret = service:add_subscription(node, stanza.attr.from, jid, options);
	local reply;
	if ok then
		reply = st.reply(stanza)
			:tag("pubsub", { xmlns = xmlns_pubsub })
				:tag("subscription", {
					node = node,
					jid = jid,
					subscription = "subscribed"
				}):up();
		if options_tag then
			reply:add_child(options_tag);
		end
	else
		reply = pubsub_error_reply(stanza, ret);
	end
	origin.send(reply);
	local ok, config = service:get_node_config(node, true);
	if ok and config.send_last_published_item ~= "never" then
		local ok, id, item = service:get_last_item(node, jid);
		if not (ok and id) then return; end
		service.config.broadcaster("items", node, { [jid] = true }, item);
	end
end

function handlers.set_unsubscribe(origin, stanza, unsubscribe, service)
	local node, jid = unsubscribe.attr.node, unsubscribe.attr.jid;
	jid = jid_prep(jid);
	if not (node and jid) then
		origin.send(pubsub_error_reply(stanza, jid and "nodeid-required" or "invalid-jid"));
		return true;
	end
	local ok, ret = service:remove_subscription(node, stanza.attr.from, jid);
	local reply;
	if ok then
		reply = st.reply(stanza)
			:tag("pubsub", { xmlns = xmlns_pubsub })
				:tag("subscription", {
					node = node,
					jid = jid,
					subscription = "none"
				}):up();
	else
		reply = pubsub_error_reply(stanza, ret);
	end
	origin.send(reply);
	return true;
end

function handlers.get_options(origin, stanza, options, service)
	local node, jid = options.attr.node, options.attr.jid;
	jid = jid_prep(jid);
	if not (node and jid) then
		origin.send(pubsub_error_reply(stanza, jid and "nodeid-required" or "invalid-jid"));
		return true;
	end
	local ok, ret = service:get_subscription(node, stanza.attr.from, jid);
	if not ok then
		origin.send(pubsub_error_reply(stanza, "not-subscribed"));
		return true;
	end
	if ret == true then ret = {} end
	origin.send(st.reply(stanza)
		:tag("pubsub", { xmlns = xmlns_pubsub })
			:tag("options", { node = node, jid = jid })
				:add_child(subscribe_options_form:form(ret)));
	return true;
end

function handlers.set_options(origin, stanza, options, service)
	local node, jid = options.attr.node, options.attr.jid;
	jid = jid_prep(jid);
	if not (node and jid) then
		origin.send(pubsub_error_reply(stanza, jid and "nodeid-required" or "invalid-jid"));
		return true;
	end
	local ok, ret = service:get_subscription(node, stanza.attr.from, jid);
	if not ok then
		origin.send(pubsub_error_reply(stanza, ret));
		return true;
	elseif not ret then
		origin.send(pubsub_error_reply(stanza, "not-subscribed"));
		return true;
	end
	local old_subopts = ret;
	local new_subopts, err = subscribe_options_form:data(options.tags[1], old_subopts);
	if err then
		origin.send(st.error_reply(stanza, "modify", "bad-request", dataform_error_message(err)));
		return true;
	end
	local ok, err = service:add_subscription(node, stanza.attr.from, jid, new_subopts);
	if not ok then
		origin.send(pubsub_error_reply(stanza, err));
		return true;
	end
	origin.send(st.reply(stanza));
	return true;
end

function handlers.set_publish(origin, stanza, publish, service)
	local node = publish.attr.node;
	if not node then
		origin.send(pubsub_error_reply(stanza, "nodeid-required"));
		return true;
	end
	local required_config = nil;
	local publish_options = stanza.tags[1]:get_child("publish-options");
	if publish_options then
		-- Ensure that the node configuration matches the values in publish-options
		local publish_options_form = publish_options:get_child("x", "jabber:x:data");
		local err;
		required_config, err = node_config_form:data(publish_options_form);
		if err then
			origin.send(st.error_reply(stanza, "modify", "bad-request", dataform_error_message(err)));
			return true
		end
	end
	local item = publish:get_child("item");
	local id = (item and item.attr.id);
	if not id then
		id = uuid_generate();
		if item then
			item.attr.id = id;
		end
	end
	if item then
		item.attr.publisher = service.config.normalize_jid(stanza.attr.from);
	end
	local ok, ret = service:publish(node, stanza.attr.from, id, item, required_config);
	local reply;
	if ok then
		if type(ok) == "string" then
			id = ok;
		end
		reply = st.reply(stanza)
			:tag("pubsub", { xmlns = xmlns_pubsub })
				:tag("publish", { node = node })
					:tag("item", { id = id });
	else
		reply = pubsub_error_reply(stanza, ret);
	end
	origin.send(reply);
	return true;
end

function handlers.set_retract(origin, stanza, retract, service)
	local node, notify = retract.attr.node, retract.attr.notify;
	notify = (notify == "1") or (notify == "true");
	local id = retract:get_child_attr("item", nil, "id");
	if not (node and id) then
		origin.send(pubsub_error_reply(stanza, node and "item-not-found" or "nodeid-required"));
		return true;
	end
	local reply, notifier;
	if notify then
		notifier = st.stanza("retract", { id = id });
	end
	local ok, ret = service:retract(node, stanza.attr.from, id, notifier);
	if ok then
		reply = st.reply(stanza);
	else
		reply = pubsub_error_reply(stanza, ret);
	end
	origin.send(reply);
	return true;
end

function handlers.owner_set_purge(origin, stanza, purge, service)
	local node = purge.attr.node;
	local reply;
	if not node then
		origin.send(pubsub_error_reply(stanza, "nodeid-required"));
		return true;
	end
	local ok, ret = service:purge(node, stanza.attr.from, true);
	if ok then
		reply = st.reply(stanza);
	else
		reply = pubsub_error_reply(stanza, ret);
	end
	origin.send(reply);
	return true;
end

function handlers.owner_get_configure(origin, stanza, config, service)
	local node = config.attr.node;
	if not node then
		origin.send(pubsub_error_reply(stanza, "nodeid-required"));
		return true;
	end

	local ok, node_config = service:get_node_config(node, stanza.attr.from);
	if not ok then
		origin.send(pubsub_error_reply(stanza, node_config));
		return true;
	end

	local reply = st.reply(stanza)
		:tag("pubsub", { xmlns = xmlns_pubsub_owner })
			:tag("configure", { node = node })
				:add_child(node_config_form:form(node_config));
	origin.send(reply);
	return true;
end

function handlers.owner_set_configure(origin, stanza, config, service)
	local node = config.attr.node;
	if not node then
		origin.send(pubsub_error_reply(stanza, "nodeid-required"));
		return true;
	end
	if not service:may(node, stanza.attr.from, "configure") then
		origin.send(pubsub_error_reply(stanza, "forbidden"));
		return true;
	end
	local config_form = config:get_child("x", "jabber:x:data");
	if not config_form then
		origin.send(st.error_reply(stanza, "modify", "bad-request", "Missing dataform"));
		return true;
	end
	local ok, old_config = service:get_node_config(node, stanza.attr.from);
	if not ok then
		origin.send(pubsub_error_reply(stanza, old_config));
		return true;
	end
	local new_config, err = node_config_form:data(config_form, old_config);
	if err then
		origin.send(st.error_reply(stanza, "modify", "bad-request", dataform_error_message(err)));
		return true;
	end
	local ok, err = service:set_node_config(node, stanza.attr.from, new_config);
	if not ok then
		origin.send(pubsub_error_reply(stanza, err));
		return true;
	end
	origin.send(st.reply(stanza));
	return true;
end

function handlers.owner_get_default(origin, stanza, default, service) -- luacheck: ignore 212/default
	local reply = st.reply(stanza)
		:tag("pubsub", { xmlns = xmlns_pubsub_owner })
			:tag("default")
				:add_child(node_config_form:form(service.node_defaults));
	origin.send(reply);
	return true;
end

function handlers.owner_get_affiliations(origin, stanza, affiliations, service)
	local node = affiliations.attr.node;
	if not node then
		origin.send(pubsub_error_reply(stanza, "nodeid-required"));
		return true;
	end
	if not service:may(node, stanza.attr.from, "set_affiliation") then
		origin.send(pubsub_error_reply(stanza, "forbidden"));
		return true;
	end

	local node_obj = service.nodes[node];
	if not node_obj then
		origin.send(pubsub_error_reply(stanza, "item-not-found"));
		return true;
	end

	local reply = st.reply(stanza)
		:tag("pubsub", { xmlns = xmlns_pubsub_owner })
			:tag("affiliations", { node = node });

	for jid, affiliation in pairs(node_obj.affiliations) do
		reply:tag("affiliation", { jid = jid, affiliation = affiliation }):up();
	end

	origin.send(reply);
	return true;
end

function handlers.owner_set_affiliations(origin, stanza, affiliations, service)
	local node = affiliations.attr.node;
	if not node then
		origin.send(pubsub_error_reply(stanza, "nodeid-required"));
		return true;
	end
	if not service:may(node, stanza.attr.from, "set_affiliation") then
		origin.send(pubsub_error_reply(stanza, "forbidden"));
		return true;
	end

	local node_obj = service.nodes[node];
	if not node_obj then
		origin.send(pubsub_error_reply(stanza, "item-not-found"));
		return true;
	end

	for affiliation_tag in affiliations:childtags("affiliation") do
		local jid = affiliation_tag.attr.jid;
		local affiliation = affiliation_tag.attr.affiliation;

		jid = jid_prep(jid);
		if affiliation == "none" then affiliation = nil; end

		local ok, err = service:set_affiliation(node, stanza.attr.from, jid, affiliation);
		if not ok then
			-- FIXME Incomplete error handling,
			-- see XEP 60 8.9.2.4 Multiple Simultaneous Modifications
			origin.send(pubsub_error_reply(stanza, err));
			return true;
		end
	end

	local reply = st.reply(stanza);
	origin.send(reply);
	return true;
end

local function create_encapsulating_item(id, payload, publisher)
	local item = st.stanza("item", { id = id, publisher = publisher, xmlns = xmlns_pubsub });
	item:add_child(payload);
	return item;
end

local function archive_itemstore(archive, max_items, user, node)
	module:log("debug", "Creation of archive itemstore for node %s with limit %d", node, max_items);
	local get_set = {};
	function get_set:items() -- luacheck: ignore 212/self
		local data, err = archive:find(user, {
			limit = tonumber(max_items);
			reverse = true;
		});
		if not data then
			module:log("error", "Unable to get items: %s", err);
			return true;
		end
		module:log("debug", "Listed items %s", data);
		return function()
			-- luacheck: ignore 211/when
			local id, payload, when, publisher = data();
			if id == nil then
				return;
			end
			local item = create_encapsulating_item(id, payload, publisher);
			return id, item;
		end;
	end
	function get_set:get(key) -- luacheck: ignore 212/self
		local data, err = archive:find(user, {
			key = key;
			-- Get the last item with that key, if the archive doesn't deduplicate
			reverse = true,
			limit = 1;
		});
		if not data then
			module:log("error", "Unable to get item: %s", err);
			return nil, err;
		end
		local id, payload, when, publisher = data();
		module:log("debug", "Get item %s (published at %s by %s)", id, when, publisher);
		if id == nil then
			return nil;
		end
		return create_encapsulating_item(id, payload, publisher);
	end
	function get_set:set(key, value) -- luacheck: ignore 212/self
		local data, err;
		if value ~= nil then
			local publisher = value.attr.publisher;
			local payload = value.tags[1];
			data, err = archive:append(user, key, payload, time_now(), publisher);
		else
			data, err = archive:delete(user, { key = key; });
		end
		-- TODO archive support for maintaining maximum items
		archive:delete(user, {
			truncate = max_items;
		});
		if not data then
			module:log("error", "Unable to set item: %s", err);
			return nil, err;
		end
		return data;
	end
	function get_set:clear() -- luacheck: ignore 212/self
		return archive:delete(user);
	end
	function get_set:resize(size) -- luacheck: ignore 212/self
		max_items = size;
		return archive:delete(user, {
			truncate = size;
		});
	end
	function get_set:head()
		-- This should conveniently return the most recent item
		local item = self:get(nil);
		if item then
			return item.attr.id, item;
		end
	end
	return get_set;
end
_M.archive_itemstore = archive_itemstore;

return _M;