From a9d7b0698cb8b44183c112280bfb8ec23b230218 Mon Sep 17 00:00:00 2001
From: TeoV <teofil.voivozeanu@itsyscom.com>
Date: Thu, 28 May 2020 13:24:52 +0300
Subject: [PATCH] Connect to dispatcher only when the call is made

---
 engine/datamanager.go         | 11 -----------
 engine/dispatcherprfl.go      | 13 +++++++++++--
 engine/dispatcherprfl_test.go |  3 ---
 utils/errors.go               | 13 +++++--------
 4 files changed, 16 insertions(+), 24 deletions(-)

diff --git a/engine/datamanager.go b/engine/datamanager.go
index 3e00485b4..7173c30eb 100644
--- a/engine/datamanager.go
+++ b/engine/datamanager.go
@@ -22,7 +22,6 @@ import (
 	"github.com/cgrates/cgrates/config"
 	"github.com/cgrates/cgrates/utils"
 	"github.com/cgrates/ltcache"
-	"github.com/cgrates/rpcclient"
 )
 
 var (
@@ -2171,16 +2170,6 @@ func (dm *DataManager) GetDispatcherHost(tenant, id string, cacheRead, cacheWrit
 		}
 	}
 	if cacheWrite {
-		cfg := config.CgrConfig()
-		if dH.rpcConn, err = NewRPCPool( // send it wil lazy connect on true and try to connect only when the call is make
-			rpcclient.PoolFirst,
-			cfg.TlsCfg().ClientKey,
-			cfg.TlsCfg().ClientCerificate, cfg.TlsCfg().CaCertificate,
-			cfg.GeneralCfg().ConnectAttempts, cfg.GeneralCfg().Reconnects,
-			cfg.GeneralCfg().ConnectTimeout, cfg.GeneralCfg().ReplyTimeout,
-			dH.Conns, IntRPC.GetInternalChanel(), true); err != nil {
-			return nil, err
-		}
 		Cache.Set(utils.CacheDispatcherHosts, tntID, dH, nil,
 			cacheCommit(transactionID), transactionID)
 	}
diff --git a/engine/dispatcherprfl.go b/engine/dispatcherprfl.go
index 68c32765c..6e59d0a51 100644
--- a/engine/dispatcherprfl.go
+++ b/engine/dispatcherprfl.go
@@ -138,9 +138,18 @@ func (dH *DispatcherHost) TenantID() string {
 }
 
 // GetRPCConnection builds or returns the cached connection
-func (dH *DispatcherHost) Call(serviceMethod string, args interface{}, reply interface{}) error {
+func (dH *DispatcherHost) Call(serviceMethod string, args interface{}, reply interface{}) (err error) {
 	if dH.rpcConn == nil {
-		return utils.ErrNotConnected
+		cfg := config.CgrConfig()
+		if dH.rpcConn, err = NewRPCPool(
+			rpcclient.PoolFirst,
+			cfg.TlsCfg().ClientKey,
+			cfg.TlsCfg().ClientCerificate, cfg.TlsCfg().CaCertificate,
+			cfg.GeneralCfg().ConnectAttempts, cfg.GeneralCfg().Reconnects,
+			cfg.GeneralCfg().ConnectTimeout, cfg.GeneralCfg().ReplyTimeout,
+			dH.Conns, IntRPC.GetInternalChanel(), false); err != nil {
+			return
+		}
 	}
 	return dH.rpcConn.Call(serviceMethod, args, reply)
 }
diff --git a/engine/dispatcherprfl_test.go b/engine/dispatcherprfl_test.go
index bb146af46..b04b8f443 100644
--- a/engine/dispatcherprfl_test.go
+++ b/engine/dispatcherprfl_test.go
@@ -245,9 +245,6 @@ func TestDispatcherHostCall(t *testing.T) {
 		reply:         utils.StringPointer(""),
 	}
 	var reply string
-	if err := dspHost.Call(utils.AttributeSv1Ping, &utils.CGREvent{}, &reply); err == nil || err.Error() != utils.ErrNotConnected.Error() {
-		t.Errorf("Expected: %s , received: %v", utils.ErrNotConnected.Error(), err)
-	}
 	dspHost.rpcConn = tRPC
 	if err := dspHost.Call(utils.AttributeSv1Ping, &utils.CGREvent{}, &reply); err != nil {
 		t.Error(err)
diff --git a/utils/errors.go b/utils/errors.go
index 7b00756be..bfadab66e 100644
--- a/utils/errors.go
+++ b/utils/errors.go
@@ -24,7 +24,6 @@ import (
 	"net"
 	"net/rpc"
 	"strings"
-	"syscall"
 )
 
 var (
@@ -244,11 +243,10 @@ func IsNetworkError(err error) bool {
 	if err == nil {
 		return false
 	}
-	if operr, ok := err.(*net.OpError); ok &&
-		(strings.HasSuffix(operr.Err.Error(),
-			syscall.ECONNRESET.Error()) ||
-			(strings.HasSuffix(operr.Err.Error(),
-				syscall.ECONNREFUSED.Error()))) { // connection reset
+	if _, isNetError := err.(*net.OpError); isNetError { // connection reset
+		return true
+	}
+	if _, isDNSError := err.(*net.DNSError); isDNSError {
 		return true
 	}
 	return err.Error() == rpc.ErrShutdown.Error() ||
@@ -256,8 +254,7 @@ func IsNetworkError(err error) bool {
 		err.Error() == ErrDisconnected.Error() ||
 		err.Error() == ErrReplyTimeout.Error() ||
 		err.Error() == ErrSessionNotFound.Error() ||
-		strings.HasPrefix(err.Error(), "rpc: can't find service") ||
-		strings.HasSuffix(err.Error(), "no such host")
+		strings.HasPrefix(err.Error(), "rpc: can't find service")
 }
 
 func ErrPathNotReachable(path string) error {