package svc // import "github.com/getwtxt/getwtxt/svc" import ( "log" "os" "path/filepath" "strings" "sync" "time" "github.com/fsnotify/fsnotify" "github.com/spf13/viper" ) // Configuration values are held in an instance of // this struct. type Configuration struct { Mu sync.RWMutex Port int `yaml:"ListenPort"` LogFile string `yaml:"LogFile"` DBType string `yaml:"DatabaseType"` DBPath string `yaml:"DatabasePath"` AssetsDir string `yaml:"-"` StdoutLogging bool `yaml:"StdoutLogging"` CacheInterval time.Duration `yaml:"StatusFetchInterval"` DBInterval time.Duration `yaml:"DatabasePushInterval"` LastCache time.Time `yaml:"-"` LastPush time.Time `yaml:"-"` Instance `yaml:"Instance"` } // Instance refers to meta data about // this specific instance of getwtxt type Instance struct { Vers string `yaml:"-"` Name string `yaml:"Instance.SiteName"` URL string `yaml:"Instance.URL"` Owner string `yaml:"Instance.OwnerName"` Mail string `yaml:"Instance.Email"` Desc string `yaml:"Instance.Description"` } // This is a wrapper for a *time.Ticker // that adds another channel. It's used // to signal to the ticker goroutines // that they should stop the tickers // and exit. type tick struct { isDB bool t *time.Ticker exit chan bool } // Creates a new instance of a tick func initTicker(db bool, interval time.Duration) *tick { return &tick{ isDB: db, t: time.NewTicker(interval), exit: make(chan bool, 1), } } // Sends the signal to stop the tickers // and for their respective goroutines // to exit. func killTickers() { ct := <-cTickC dt := <-dbTickC ct.exit <- true dt.exit <- true } // Waits for a signal from the database // *tick. Either stops the ticker and // kills the goroutine or it will // update cache / push the DB to disk func dataTimer(tkr *tick) { for { select { case signal := <-tkr.t.C: if tkr.isDB { errLog("", pushDB()) log.Printf("Database push took: %v\n", time.Since(signal)) continue } cacheUpdate() log.Printf("Cache update took: %v\n", time.Since(signal)) case <-tkr.exit: tkr.t.Stop() return } } } // Called on start-up. Initializes everything // related to configuration values. func initConfig() { log.Printf("Loading configuration ...\n") parseConfigFlag() setConfigDefaults() if err := viper.ReadInConfig(); err != nil { log.Printf("%v\n", err.Error()) log.Printf("Using defaults ...\n") bindConfig() return } viper.WatchConfig() viper.OnConfigChange(reInit) bindConfig() } // Called when a change is detected in the // configuration file. Closes log file, // closes database connection, stops all // tickers, then binds new configuration // values, opens new log file, connects to // new database, and starts new cache and // database tickers. func reInit(e fsnotify.Event) { log.Printf("%v. Reloading...\n", e.String()) if !confObj.StdoutLogging { closeLog <- true } killTickers() killDB() bindConfig() initLogging() initDatabase() initPersistence() } // Registers either stdout or a specified file // to the default logger. func initLogging() { confObj.Mu.RLock() if confObj.StdoutLogging { log.SetOutput(os.Stdout) } else { logfile, err := os.OpenFile(confObj.LogFile, os.O_APPEND|os.O_CREATE|os.O_WRONLY, 0600) errLog("Could not open log file: ", err) // Listen for the signal to close the log file // in a separate thread. Passing it as an argument // to prevent race conditions when the config is // reloaded. go func(logfile *os.File) { <-closeLog log.Printf("Closing log file ...\n\n") errLog("Could not close log file: ", logfile.Close()) }(logfile) log.SetOutput(logfile) } confObj.Mu.RUnlock() } // Default values should a config file // not be available. func setConfigDefaults() { viper.SetDefault("ListenPort", 9001) viper.SetDefault("LogFile", "getwtxt.log") viper.SetDefault("DatabasePath", "getwtxt.db") viper.SetDefault("AssetsDirectory", "assets") viper.SetDefault("DatabaseType", "leveldb") viper.SetDefault("StdoutLogging", false) viper.SetDefault("ReCacheInterval", "1h") viper.SetDefault("DatabasePushInterval", "5m") viper.SetDefault("Instance.SiteName", "getwtxt") viper.SetDefault("Instance.OwnerName", "Anonymous Microblogger") viper.SetDefault("Instance.Email", "nobody@knows") viper.SetDefault("Instance.URL", "https://twtxt.example.com") viper.SetDefault("Instance.Description", "A fast, resilient twtxt registry server written in Go!") } // Reads data from the configuration // flag and acts accordingly. func parseConfigFlag() { if *flagConfFile == "" { viper.SetConfigName("getwtxt") viper.SetConfigType("yml") viper.AddConfigPath(".") viper.AddConfigPath("/usr/local/getwtxt") viper.AddConfigPath("/etc") viper.AddConfigPath("/usr/local/etc") } else { path, file := filepath.Split(*flagConfFile) if path == "" { path = "." } filename := strings.Split(file, ".") viper.SetConfigName(filename[0]) viper.SetConfigType(filename[1]) viper.AddConfigPath(path) } } // Simply goes down the list of fields // in the confObj instance of &Configuration{}, // assigning values from the config file. func bindConfig() { confObj.Mu.Lock() confObj.Port = viper.GetInt("ListenPort") confObj.LogFile = viper.GetString("LogFile") confObj.DBType = strings.ToLower(viper.GetString("DatabaseType")) if *flagDBType != "" { confObj.DBType = *flagDBType } confObj.DBPath = viper.GetString("DatabasePath") if *flagDBPath != "" { confObj.DBPath = *flagDBPath } log.Printf("Using %v database: %v\n", confObj.DBType, confObj.DBPath) confObj.AssetsDir = viper.GetString("AssetsDirectory") if *flagAssets != "" { confObj.AssetsDir = *flagAssets } confObj.StdoutLogging = viper.GetBool("StdoutLogging") if confObj.StdoutLogging { log.Printf("Logging to stdout\n") } else { log.Printf("Logging to %v\n", confObj.LogFile) } confObj.CacheInterval = viper.GetDuration("StatusFetchInterval") log.Printf("User status fetch interval: %v\n", confObj.CacheInterval) confObj.DBInterval = viper.GetDuration("DatabasePushInterval") log.Printf("Database push interval: %v\n", confObj.DBInterval) confObj.LastCache = time.Now() confObj.LastPush = time.Now() confObj.Instance.Vers = Vers confObj.Instance.Name = viper.GetString("Instance.SiteName") confObj.Instance.URL = viper.GetString("Instance.URL") confObj.Instance.Owner = viper.GetString("Instance.OwnerName") confObj.Instance.Mail = viper.GetString("Instance.Email") confObj.Instance.Desc = viper.GetString("Instance.Description") confObj.Mu.Unlock() }