mod_reminders: Initial commit for supporting Reminders ProtoXEP
See https://tenak.net/marcos/xeps/reminders.html
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/mod_reminders/README.md Thu Feb 27 00:59:17 2020 +0100
@@ -0,0 +1,18 @@
+---
+labels:
+- 'Stage-alpha'
+summary: Enable ProtoXEP: Reminders support'
+...
+
+
+Introduction
+============
+
+`mod_reminders` implements ProtoXEP: Reminders.
+
+Usage
+=====
+
+Place the sibling `mod_reminders.lua` somewhere under your
+`plugins_path`.
+
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/mod_reminders/mod_reminders.lua Thu Feb 27 00:59:17 2020 +0100
@@ -0,0 +1,178 @@
+-- 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", {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 rem = st.clone(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
+ rem.attr.id = id.medium();
+ local data = {
+ id = rem.attr.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");