mqttagent

main.go (3865B)

---

 /*
  * Copyright (c) 2025, Natacha Porté
  *
  * Permission to use, copy, modify, and distribute this software for any
  * purpose with or without fee is hereby granted, provided that the above
  * copyright notice and this permission notice appear in all copies.
  *
  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  */
 
 package main
 
 import (
 	"database/sql"
 	"log"
 	"os"
 
 	"instinctive.eu/go/mqttagent"
 	_ "github.com/glebarez/go-sqlite"
 	luajson "github.com/layeh/gopher-json"
 	"github.com/yuin/gopher-lua"
 )
 
 type fullMqttAgent struct {
 	db             *sql.DB
 	insertTopic    *sql.Stmt
 	insertReceived *sql.Stmt
 }
 
 func (agent *fullMqttAgent) Setup(L *lua.LState) {
 	luajson.Preload(L)
 
 	L.SetGlobal("sqlog", L.NewFunction(func(L *lua.LState) int {
 		arg := L.CheckString(1)
 		if err := agent.connect(arg); err != nil {
 			log.Println(err)
 			L.Push(lua.LNil)
 			L.Push(lua.LString(err.Error()))
 			return 2
 		} else {
 			L.Push(lua.LTrue)
 			return 1
 		}
 	}))
 }
 
 func (agent *fullMqttAgent) Log(L *lua.LState, msg *mqttagent.MqttMessage) {
 	if agent.insertTopic == nil || agent.insertReceived == nil {
 		return
 	}
 
 	if _, err := agent.insertTopic.Exec(msg.Topic); err != nil {
 		log.Println(err)
 		return
 	}
 
 	if _, err := agent.insertReceived.Exec((msg.Timestamp/86400.0)+2440587.5, msg.Topic, msg.Message); err != nil {
 		log.Println(err)
 		return
 	}
 }
 
 func (agent *fullMqttAgent) Teardown(L *lua.LState) {
 	if agent.insertReceived != nil {
 		agent.insertReceived.Close()
 	}
 
 	if agent.insertTopic != nil {
 		agent.insertTopic.Close()
 	}
 
 	if agent.db != nil {
 		agent.db.Close()
 	}
 }
 
 func (agent *fullMqttAgent) connect(connectionString string) error {
 	if agent.insertReceived != nil {
 		agent.insertReceived.Close()
 		agent.insertReceived = nil
 	}
 
 	if agent.insertTopic != nil {
 		agent.insertTopic.Close()
 		agent.insertTopic = nil
 	}
 
 	if agent.db != nil {
 		agent.db.Close()
 		agent.db = nil
 	}
 
 	db, err := sql.Open("sqlite", connectionString)
 	if err != nil {
 		return err
 	}
 
 	_, err = db.Exec(`
 CREATE TABLE IF NOT EXISTS
   topics(id INTEGER PRIMARY KEY AUTOINCREMENT,
          name TEXT NOT NULL);
 `)
 	if err != nil {
 		db.Close()
 		return err
 	}
 
 	_, err = db.Exec("CREATE INDEX IF NOT EXISTS i_topics ON topics(name);")
 	if err != nil {
 		db.Close()
 		return err
 	}
 
 	_, err = db.Exec(`
 CREATE TABLE IF NOT EXISTS
   received(timestamp INTEGER NOT NULL DEFAULT CURRENT_TIMESTAMP,
            topic_id INTEGER NOT NULL,
            message TEXT NOT NULL,
            FOREIGN KEY (topic_id) REFERENCES topics (id));
 `)
 	if err != nil {
 		db.Close()
 		return err
 	}
 
 	_, err = db.Exec("CREATE INDEX IF NOT EXISTS i_time ON received(timestamp);")
 	if err != nil {
 		db.Close()
 		return err
 	}
 
 	_, err = db.Exec("CREATE INDEX IF NOT EXISTS i_topicid ON received(topic_id);")
 	if err != nil {
 		db.Close()
 		return err
 	}
 
 	s1, err := db.Prepare("INSERT OR IGNORE INTO topics(name) VALUES (?);")
 	if err != nil {
 		db.Close()
 		return err
 	}
 
 	s2, err := db.Prepare(`
 INSERT INTO received (timestamp, topic_id, message)
 VALUES (?, (SELECT id FROM topics WHERE name = ?), ?);
 `)
 	if err != nil {
 		s1.Close()
 		db.Close()
 		return err
 	}
 
 	agent.db = db
 	agent.insertTopic = s1
 	agent.insertReceived = s2
 	return nil
 }
 
 func main() {
 	var agent fullMqttAgent
 
 	main_script := "mqttagent.lua"
 	if len(os.Args) > 1 {
 		main_script = os.Args[1]
 	}
 
 	mqttagent.Run(&agent, main_script)
 
 	os.Exit(0)
 }