Bump golangci-lint to v1.24.0, linter fixes and general code improvements (#478)

* Bump golangci-lint version, update Go version deps and generic code improvements

* Fix wesbocket resp nil check and zip closures

* Update pprof path

engine/database.go

@@ -14,7 +14,7 @@ import (
 )
 
 var (
-	dbConn *database.Db
+	dbConn *database.Instance
 )
 
 type databaseManager struct {

engine/orders.go

@@ -24,8 +24,9 @@ var (
 // should not be exported as it can have large impact if used improperly
 func (o *orderStore) get() map[string][]*order.Detail {
 	o.m.RLock()
-	defer o.m.RUnlock()
-	return o.Orders
+	orders := o.Orders
+	o.m.RUnlock()
+	return orders
 }
 
 // GetByExchangeAndID returns a specific order by exchange and id

engine/restful_router.go

@@ -3,7 +3,7 @@ package engine
 import (
 	"fmt"
 	"net/http"
-	_ "net/http/pprof" // nolint: gosec
+	"net/http/pprof"
 	"runtime"
 	"strconv"
 	"strings"
@@ -90,10 +90,10 @@ func newRouter(isREST bool) *mux.Router {
 				runtime.SetMutexProfileFraction(Bot.Config.Profiler.MutexProfileFraction)
 			}
 			log.Debugf(log.RESTSys,
-				"HTTP Go performance profiler (pprof) endpoint enabled: http://%s:%d/debug/pprof\n",
+				"HTTP Go performance profiler (pprof) endpoint enabled: http://%s:%d/debug/pprof/\n",
 				common.ExtractHost(listenAddr),
 				common.ExtractPort(listenAddr))
-			router.PathPrefix("/debug").Handler(http.DefaultServeMux)
+			router.PathPrefix("/debug/pprof/").HandlerFunc(pprof.Index)
 		}
 	} else {
 		routes = []Route{

engine/syncer.go

@@ -412,7 +412,6 @@ func (e *ExchangeCurrencyPairSyncer) worker() {
 									}
 									printTickerSummary(result, c.Pair, c.AssetType, exchangeName, "REST", err)
 									if err == nil {
-										//nolint:gocritic Bot.CommsRelayer.StageTickerData(exchangeName, c.AssetType, result)
 										if Bot.Config.RemoteControl.WebsocketRPC.Enabled {
 											relayWebsocketEvent(result, "ticker_update", c.AssetType.String(), exchangeName)
 										}
@@ -452,7 +451,6 @@ func (e *ExchangeCurrencyPairSyncer) worker() {
 								result, err := exchanges[x].UpdateOrderbook(c.Pair, c.AssetType)
 								printOrderbookSummary(result, c.Pair, c.AssetType, exchangeName, "REST", err)
 								if err == nil {
-									//nolint:gocritic Bot.CommsRelayer.StageOrderbookData(exchangeName, c.AssetType, result)
 									if Bot.Config.RemoteControl.WebsocketRPC.Enabled {
 										relayWebsocketEvent(result, "orderbook_update", c.AssetType.String(), exchangeName)
 									}

engine/websocket.go

@@ -151,7 +151,7 @@ func (c *WebsocketClient) write() {
 	defer func() {
 		c.Conn.Close()
 	}()
-	for { // nolint: gosimple
+	for { // nolint // ws client write routine loop
 		select {
 		case message, ok := <-c.Send:
 			if !ok {