General engine improvements (#437)

* Add exchange manager to engine

* Several improvements for engine and friends

1) New file.Exists func
2) gRPC TLS cert expiration date check and regeneration
3) New donation var for use across the codebase
4) Use Go log package until the logger is initialised

* Add cert tests and create dir tree if it doesn't exist for file.Write

* Link up donation address to documentation tool plus minor adjustments

* Fix remaining donation addrs

* Move non-needed reload exchange funcs

* Revert accidental config_example.json changes 🕯️

* Use go logger for logging until the logger has initiliased, otherwise no output will be seen

* Link up portfolio delay val and other fixes

* Run go mod tidy after dependabot PR

* Address nitterinos

engine/exchange.go

@@ -45,6 +45,11 @@ var (
 	ErrExchangeFailedToLoad  = errors.New("exchange failed to load")
 )
 
+type exchangeManager struct {
+	m         sync.Mutex
+	exchanges map[string]exchange.IBotExchange
+}
+
 func dryrunParamInteraction(param string) {
 	if !Bot.Settings.CheckParamInteraction {
 		return
@@ -59,67 +64,91 @@ func dryrunParamInteraction(param string) {
 	}
 }
 
-// GetExchangeByName returns an exchange given an exchange name
-func GetExchangeByName(exchName string) exchange.IBotExchange {
-	for x := range Bot.Exchanges {
-		if strings.EqualFold(Bot.Exchanges[x].GetName(), exchName) {
-			return Bot.Exchanges[x]
-		}
+func (e *exchangeManager) add(exch exchange.IBotExchange) {
+	e.m.Lock()
+	if e.exchanges == nil {
+		e.exchanges = make(map[string]exchange.IBotExchange)
 	}
+	e.exchanges[strings.ToLower(exch.GetName())] = exch
+	e.m.Unlock()
+}
+
+func (e *exchangeManager) getExchanges() []exchange.IBotExchange {
+	if e.Len() == 0 {
+		return nil
+	}
+
+	e.m.Lock()
+	defer e.m.Unlock()
+	var exchs []exchange.IBotExchange
+	for x := range e.exchanges {
+		exchs = append(exchs, e.exchanges[x])
+	}
+	return exchs
+}
+
+func (e *exchangeManager) removeExchange(exchName string) error {
+	if e.Len() == 0 {
+		return ErrNoExchangesLoaded
+	}
+	exch := e.getExchangeByName(exchName)
+	if exch == nil {
+		return ErrExchangeNotFound
+	}
+	e.m.Lock()
+	defer e.m.Unlock()
+	delete(e.exchanges, strings.ToLower(exchName))
+	log.Infof(log.ExchangeSys, "%s exchange unloaded successfully.\n", exchName)
 	return nil
 }
 
-// ReloadExchange loads an exchange config by name
-func ReloadExchange(name string) error {
-	if len(Bot.Exchanges) == 0 {
-		return ErrNoExchangesLoaded
+func (e *exchangeManager) getExchangeByName(exchangeName string) exchange.IBotExchange {
+	if e.Len() == 0 {
+		return nil
 	}
-
-	e := GetExchangeByName(name)
-	if e == nil {
-		return ErrExchangeNotFound
+	e.m.Lock()
+	defer e.m.Unlock()
+	exch, ok := e.exchanges[strings.ToLower(exchangeName)]
+	if !ok {
+		return nil
 	}
+	return exch
+}
 
-	exchCfg, err := Bot.Config.GetExchangeConfig(name)
+func (e *exchangeManager) Len() int {
+	e.m.Lock()
+	defer e.m.Unlock()
+	return len(e.exchanges)
+}
+
+func (e *exchangeManager) unloadExchange(exchangeName string) error {
+	exchCfg, err := Bot.Config.GetExchangeConfig(exchangeName)
 	if err != nil {
 		return err
 	}
 
-	e.Setup(exchCfg)
-	log.Debugf(log.ExchangeSys, "%s exchange reloaded successfully.\n", name)
-	return nil
-}
-
-// UnloadExchange unloads an exchange by name
-func UnloadExchange(name string) error {
-	if len(Bot.Exchanges) == 0 {
-		return ErrNoExchangesLoaded
-	}
-
-	if GetExchangeByName(name) == nil {
-		return ErrExchangeNotFound
-	}
-
-	exchCfg, err := Bot.Config.GetExchangeConfig(name)
+	err = e.removeExchange(exchangeName)
 	if err != nil {
 		return err
 	}
 
 	exchCfg.Enabled = false
-	err = Bot.Config.UpdateExchangeConfig(exchCfg)
-	if err != nil {
-		return err
-	}
+	return nil
+}
 
-	for x := range Bot.Exchanges {
-		if strings.EqualFold(Bot.Exchanges[x].GetName(), name) {
-			Bot.Exchanges[x].SetEnabled(false)
-			Bot.Exchanges = append(Bot.Exchanges[:x], Bot.Exchanges[x+1:]...)
-			return nil
-		}
-	}
+// GetExchangeByName returns an exchange given an exchange name
+func GetExchangeByName(exchName string) exchange.IBotExchange {
+	return Bot.exchangeManager.getExchangeByName(exchName)
+}
 
-	return ErrExchangeNotFound
+// UnloadExchange unloads an exchange by name
+func UnloadExchange(exchName string) error {
+	return Bot.exchangeManager.unloadExchange(exchName)
+}
+
+// GetExchanges retrieves the loaded exchanges
+func GetExchanges() []exchange.IBotExchange {
+	return Bot.exchangeManager.getExchanges()
 }
 
 // LoadExchange loads an exchange by name
@@ -127,10 +156,8 @@ func LoadExchange(name string, useWG bool, wg *sync.WaitGroup) error {
 	nameLower := strings.ToLower(name)
 	var exch exchange.IBotExchange
 
-	if len(Bot.Exchanges) > 0 {
-		if GetExchangeByName(name) != nil {
-			return ErrExchangeAlreadyLoaded
-		}
+	if Bot.exchangeManager.getExchangeByName(nameLower) != nil {
+		return ErrExchangeAlreadyLoaded
 	}
 
 	switch nameLower {
@@ -269,26 +296,29 @@ func LoadExchange(name string, useWG bool, wg *sync.WaitGroup) error {
 		dryrunParamInteraction("enableallexchanges")
 	}
 
-	exchCfg.Enabled = true
-	err = exch.Setup(exchCfg)
-	if err != nil {
-		return err
-	}
-
 	if !Bot.Settings.EnableExchangeHTTPRateLimiter {
 		log.Warnf(log.ExchangeSys,
 			"Loaded exchange %s rate limiting has been turned off.\n",
-			exch.GetName())
+			exch.GetName(),
+		)
 		err = exch.DisableRateLimiter()
 		if err != nil {
 			log.Errorf(log.ExchangeSys,
 				"Loaded exchange %s rate limiting cannot be turned off: %s.\n",
 				exch.GetName(),
-				err)
+				err,
+			)
 		}
 	}
 
-	Bot.Exchanges = append(Bot.Exchanges, exch)
+	exchCfg.Enabled = true
+	err = exch.Setup(exchCfg)
+	if err != nil {
+		exchCfg.Enabled = false
+		return err
+	}
+
+	Bot.exchangeManager.add(exch)
 
 	base := exch.GetBase()
 	if base.API.AuthenticatedSupport ||
@@ -322,19 +352,6 @@ func SetupExchanges() {
 	var wg sync.WaitGroup
 	configs := Bot.Config.GetAllExchangeConfigs()
 	for x := range configs {
-		if e := GetExchangeByName(configs[x].Name); e != nil {
-			err := ReloadExchange(configs[x].Name)
-			if err != nil {
-				log.Errorf(log.ExchangeSys, "ReloadExchange %s failed: %s\n", configs[x].Name, err)
-				continue
-			}
-
-			if !e.IsEnabled() {
-				UnloadExchange(configs[x].Name)
-				continue
-			}
-			return
-		}
 		if !configs[x].Enabled && !Bot.Settings.EnableAllExchanges {
 			log.Debugf(log.ExchangeSys, "%s: Exchange support: Disabled\n", configs[x].Name)
 			continue