view mod_reminders/mod_reminders.lua @ 5551:8bfcedd93a72

mod_rest: List all error conditions in OpenAPI spec These are not handled by datamanager but by util.stanza and util.error, so they are not represented in the JSON schema file.
author Kim Alvefur <zash@zash.se>
date Sat, 17 Jun 2023 16:26:33 +0200
parents 9eabd68b8e48
children
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-- mod_reminders
--
-- Copyright (C) 2020 Marcos de Vera Piquero <marcos@tenak.net>
--
-- This file is MIT/X11 licensed.
--
-- A module to support ProtoXEP: Reminders
--

local id = require "util.id"
local datetime = require"util.datetime";
local errors = require"util.error";
local jid = require"util.jid";
local st = require"util.stanza";
local os_time = os.time;

local xmlns_reminders = "urn:xmpp:reminders:0";

local reminders_store = module:open_store(xmlns_reminders, "keyval");

local reminders_errors = {
	missing_fields = {
		type = "modify";
		condition = "bad-request";
		text = "Missing required value for date or text";
	};
	invalid_dateformat = {
		type = "modify";
		condition = "bad-request";
		text = "Invalid date format";
	};
	past_date = {
		type = "modify";
		condition = "gone";
		text = "Reminder date is in the past";
	};
	store_error = {
		type = "cancel";
		condition = "internal-server-error";
		text = "Unable to persist data";
	};
};

local function reminder_error (name)
	return errors.new(name, nil, reminders_errors);
end

local function store_reminder (reminder)
	-- pushes the reminder to the store, and nothing else
	return reminders_store:set(reminder.id, reminder);
end

local function delete_reminder (reminder_id)
	-- empties the store for the given reminder_id
	return reminders_store:set(reminder_id, nil);
end

local function get_reminder (reminder_id)
	return reminders_store:get(reminder_id);
end

local function send_reminder (reminder)
	-- actually delivers the <message /> with the reminder to the user
	local bare = jid.bare(reminder.jid);
	module:log("debug", "Sending reminder %s to %s", reminder.id, bare);
	local message = st.message({ from = "localhost"; to = bare; id = id.short() })
		:tag("reminder", {id = reminder.id; xmlns = xmlns_reminders})
		:add_child(reminder.text)
		:tag("date"):text(datetime.datetime(reminder.date)):up();
	module:send(message);
	return delete_reminder(reminder.id)
end

local function schedule_reminder (reminder)
	-- schedule a module:add_timer for the given reminder
	module:log("debug", "Scheduling reminder to datetime %s", reminder.date);
	local now = os_time();
	local when = reminder.date;
	local delay = when - now;
	module:log("debug", "Reminder text: %s", reminder.text);
	local function callback ()
		send_reminder(reminder)
	end
	module:add_timer(delay, callback);
end

local function process_reminders_store ()
	-- retrieve all reminders in the store and schedule them
	for reminder_id in reminders_store:users() do
		module:log("debug", "Found stored reminder %s", reminder_id);
		local reminder = get_reminder(reminder_id);
		if reminder.date and reminder.text then
			local text = st.deserialize(reminder.text)
			module:log("debug", "Read reminder %s", reminder.id);
			-- cleanup missed reminders
			if reminder.date < os_time() then
				module:log("debug", "Deleting outdated reminder %s", reminder.id)
				delete_reminder(reminder.id)
			end
			schedule_reminder({
					date = reminder.date;
					id = reminder.id;
					jid = reminder.jid;
					text = text;	
			})
		else
			delete_reminder(reminder_id);
		end
	end
end

local function create_reminder (jid, reminder)
	local date = reminder:get_child("date");
	local text = reminder:get_child("text");
	if date == nil or text == nil then
		return nil, reminder_error("missing_fields")
	end
	local now = os_time();
	local _, parsed_date = pcall(datetime.parse, date:get_text());
	if parsed_date == nil then
		return nil, reminder_error("invalid_dateformat")
	end
	if parsed_date < now then
		return nil, reminder_error("past_date"), nil
	end
	local reminder_id = id.medium();
	local rem = st.stanza("reminder", {xmlns = xmlns_reminders; id = reminder_id});
	local data = {
		id = reminder_id;
		jid = jid;
		text = text;
		date = parsed_date;
	}
	local stored = store_reminder(data);
	if not stored then
		return nil, reminder_error("store_error")
	end
	schedule_reminder(data);
	return rem
end

local function handle_set (event)
	local origin, stanza = event.origin, event.stanza
	local reminder = stanza:get_child("reminder", xmlns_reminders);
	if reminder.attr.id ~= nil and reminder:get_child("date") == nil then
		-- delete existing reminder
		local ok = delete_reminder(reminder.attr.id);
		if ok then
			module:log("debug", "reminder %s deleted", reminder.attr.id);
			origin.send(st.reply(stanza):add_child(reminder));
		else
			module:log("debug", "failed to delete reminder %s", reminder.attr.id);
			origin.send(st.error_reply(stanza, "cancel", "internal-server-error"));
		end
		return true;
	else
		-- create new reminder
		local jid = stanza.attr.from
		local created, err = create_reminder(jid, reminder);
		if err ~= nil then
			origin.send(st.error_reply(stanza, err))
			return true;
		else
			origin.send(st.reply(stanza):add_child(created))
			return true;
		end		
	end
	origin.send(st.error_reply(stanza, "modify", "bad-request"));
	return true;
end


-- load saved reminders and set timers
process_reminders_store();

module:hook("iq-set/host/"..xmlns_reminders..":reminder", handle_set)
module:add_feature(xmlns_reminders);
module:log("debug", "Module loaded");