Mercurial > prosody-modules
view mod_pubsub_mqtt/mod_pubsub_mqtt.lua @ 5119:048e339706ba
mod_rest: Remove manual reference expansion in schema
This hack was originally added to reduce the number of definitions of
common attributes (type, to, from etc) and payloads (e.g. delay). This
predated pointers and references, and until now was needed because
parsing picked out the correct stanza kind from the schema, which broke
internal references.
Removing this hack paves the way for allowing the schema to be
configured or customized more easily.
author | Kim Alvefur <zash@zash.se> |
---|---|
date | Tue, 20 Dec 2022 21:48:28 +0100 |
parents | 85a7304cfea1 |
children |
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module:set_global(); local mqtt = module:require "mqtt"; local id = require "util.id"; local st = require "util.stanza"; local function tostring_content(item) return tostring(item[1]); end local data_translators = setmetatable({ utf8 = { from_item = function (item) return item:find("{https://prosody.im/protocol/data}data#"); end; to_item = function (payload) return st.stanza("item", { xmlns = "http://jabber.org/protocol/pubsub", id = id.medium() }) :text_tag("data", payload, { xmlns = "https://prosody.im/protocol/data" }) end; }; json = { from_item = function (item) return item:find("{urn:xmpp:json:0}json#"); end; to_item = function (payload) return st.stanza("item", { xmlns = "http://jabber.org/protocol/pubsub", id = id.medium() }) :text_tag("json", payload, { xmlns = "urn:xmpp:json:0" }); end; }; atom_title = { from_item = function (item) return item:find("{http://www.w3.org/2005/Atom}entry/title#"); end; to_item = function (payload) return st.stanza("item", { xmlns = "http://jabber.org/protocol/pubsub", id = id.medium() }) :tag("entry", { xmlns = "http://www.w3.org/2005/Atom" }) :text_tag("title", payload, { type = "text" }); end; }; }, { __index = function () return { from_item = tostring }; end; }); local pubsub_services = {}; local pubsub_subscribers = {}; local packet_handlers = {}; function handle_packet(session, packet) module:log("debug", "MQTT packet received! Length: %d", packet.length); for k,v in pairs(packet) do module:log("debug", "MQTT %s: %s", tostring(k), tostring(v)); end local handler = packet_handlers[packet.type]; if not handler then module:log("warn", "Unhandled command: %s", tostring(packet.type)); return; end handler(session, packet); end function packet_handlers.connect(session, packet) session.conn:write(mqtt.serialize_packet{ type = "connack"; data = string.char(0x00, 0x00); }); end function packet_handlers.disconnect(session, packet) session.conn:close(); end function packet_handlers.publish(session, packet) module:log("info", "PUBLISH to %s", packet.topic); local host, payload_type, node = packet.topic:match("^([^/]+)/([^/]+)/(.+)$"); if not host then module:log("warn", "Invalid topic format - expected: HOST/TYPE/NODE"); return; end local pubsub = pubsub_services[host]; if not pubsub then module:log("warn", "Unable to locate host/node: %s", packet.topic); return; end local payload_translator = data_translators[payload_type]; if not payload_translator or not payload_translator.to_item then module:log("warn", "Unsupported payload type '%s' on topic '%s'", payload_type, packet.topic); return; end local payload_item = payload_translator.to_item(packet.data); local ok, err = pubsub:publish(node, true, payload_item.attr.id, payload_item); if not ok then module:log("warn", "Error publishing MQTT data: %s", tostring(err)); end end function packet_handlers.subscribe(session, packet) for _, topic in ipairs(packet.topics) do module:log("info", "SUBSCRIBE to %s", topic); local host, payload_type, node = topic:match("^([^/]+)/([^/]+)/(.+)$"); if not host then module:log("warn", "Invalid topic format - expected: HOST/TYPE/NODE"); return; end local pubsub = pubsub_subscribers[host]; if not pubsub then module:log("warn", "Unable to locate host/node: %s", topic); return; end local node_subs = pubsub[node]; if not node_subs then node_subs = {}; pubsub[node] = node_subs; end session.subscriptions[topic] = payload_type; node_subs[session] = payload_type; end end function packet_handlers.pingreq(session, packet) session.conn:write(mqtt.serialize_packet{type = "pingresp"}); end local sessions = {}; local mqtt_listener = {}; function mqtt_listener.onconnect(conn) sessions[conn] = { conn = conn; stream = mqtt.new_stream(); subscriptions = {}; }; end function mqtt_listener.onincoming(conn, data) local session = sessions[conn]; if session then local packets = session.stream:feed(data); for i = 1, #packets do handle_packet(session, packets[i]); end end end function mqtt_listener.ondisconnect(conn) local session = sessions[conn]; for topic in pairs(session.subscriptions) do local host, node = topic:match("^([^/]+)/(.+)$"); local subs = pubsub_subscribers[host]; if subs then local node_subs = subs[node]; if node_subs then node_subs[session] = nil; end end end sessions[conn] = nil; module:log("debug", "MQTT client disconnected"); end module:provides("net", { default_port = 1883; listener = mqtt_listener; }); function module.add_host(module) local pubsub_module = hosts[module.host].modules.pubsub if pubsub_module then module:log("debug", "MQTT enabled for %s", module.host); module:depends("pubsub"); pubsub_services[module.host] = assert(pubsub_module.service); local subscribers = {}; pubsub_subscribers[module.host] = subscribers; local function handle_publish(event) -- Build MQTT packet local packet_types = setmetatable({}, { __index = function (self, payload_type) local packet = mqtt.serialize_packet{ type = "publish"; id = "\000\000"; topic = module.host.."/"..payload_type.."/"..event.node; data = data_translators[payload_type].from_item(event.item) or ""; }; rawset(self, packet); return packet; end; }); -- Broadcast to subscribers module:log("debug", "Broadcasting PUBLISH to subscribers of %s/*/%s", module.host, event.node); for session, payload_type in pairs(subscribers[event.node] or {}) do session.conn:write(packet_types[payload_type]); module:log("debug", "Sent to %s", tostring(session)); end end pubsub_services[module.host].events.add_handler("item-published", handle_publish); function module.unload() module:log("debug", "MQTT disabled for %s", module.host); pubsub_module.service.remove_handler("item-published", handle_publish); pubsub_services[module.host] = nil; pubsub_subscribers[module.host] = nil; end end end