feat: allow dial timeout and keep alive period to be configurable

Settings are applied to every connection.

Signed-off-by: Andrey Smirnov <smirnov.andrey@gmail.com>

Author: smira

go.mod

@@ -2,6 +2,8 @@ module github.com/talos-systems/go-loadbalancer
 
 go 1.14
 
+replace inet.af/tcpproxy => github.com/smira/tcpproxy v0.0.0-20201014215138-25207f0e2105
+
 require (
 	github.com/davecgh/go-spew v1.1.1 // indirect
 	github.com/kr/pretty v0.1.0 // indirect

go.sum

@@ -8,17 +8,15 @@ github.com/kr/text v0.1.0 h1:45sCR5RtlFHMR4UwH9sdQ5TC8v0qDQCHnXt+kaKSTVE=
 github.com/kr/text v0.1.0/go.mod h1:4Jbv+DJW3UT/LiOwJeYQe1efqtUx/iVham/4vfdArNI=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/smira/tcpproxy v0.0.0-20201014215138-25207f0e2105 h1:R88m/hWIpn4uM+Jx6XgV+aACDpOwOR4MUciaU1GnaYM=
+github.com/smira/tcpproxy v0.0.0-20201014215138-25207f0e2105/go.mod h1:yDIWrelwlTRXdKvQqqQ+8lCwCjbSRtkat49REnui7hk=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
 github.com/stretchr/testify v1.6.1 h1:hDPOHmpOpP40lSULcqw7IrRb/u7w6RpDC9399XyoNd0=
 github.com/stretchr/testify v1.6.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
-github.com/talos-systems/go-retry v0.0.0-20200902131929-073067bd95a7 h1:KL8Nz3tlwA1UhTsoGQXwg1gDoYPldiwfTtcipcuALXM=
-github.com/talos-systems/go-retry v0.0.0-20200902131929-073067bd95a7/go.mod h1:HiXQqyVStZ35uSY/MTLWVvQVmC3lIW2MS5VdDaMtoKM=
 github.com/talos-systems/go-retry v0.1.0 h1:O+OeZR54CQ1+ch99p/81Pqi5GqJH6LIu1MTN/N0vd78=
 github.com/talos-systems/go-retry v0.1.0/go.mod h1:HiXQqyVStZ35uSY/MTLWVvQVmC3lIW2MS5VdDaMtoKM=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/check.v1 v1.0.0-20190902080502-41f04d3bba15 h1:YR8cESwS4TdDjEe65xsg0ogRM/Nc3DYOhEAlW+xobZo=
 gopkg.in/check.v1 v1.0.0-20190902080502-41f04d3bba15/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c h1:dUUwHk2QECo/6vqA44rthZ8ie2QXMNeKRTHCNY2nXvo=
 gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
-inet.af/tcpproxy v0.0.0-20200125044825-b6bb9b5b8252 h1:gmJCKidOfjKDUHF1jjke+I+2iQIyE3HNNxu2OKO/FUI=
-inet.af/tcpproxy v0.0.0-20200125044825-b6bb9b5b8252/go.mod h1:zq+R+tLcdHugi7Jt+FtIQY6m6wtX34lr2CdQVH2fhW0=

loadbalancer/loadbalancer.go

@@ -10,6 +10,7 @@ import (
 	"fmt"
 	"log"
 	"net"
+	"time"
 
 	"inet.af/tcpproxy"
 
@@ -27,6 +28,9 @@ import (
 type TCP struct {
 	tcpproxy.Proxy
 
+	DialTimeout     time.Duration
+	KeepAlivePeriod time.Duration
+
 	Logger *log.Logger
 
 	routes map[string]*upstream.List
@@ -51,8 +55,10 @@ func (upstream lbUpstream) HealthCheck(ctx context.Context) error {
 }
 
 type lbTarget struct {
-	list   *upstream.List
-	logger *log.Logger
+	list            *upstream.List
+	logger          *log.Logger
+	dialTimeout     time.Duration
+	keepAlivePeriod time.Duration
 }
 
 func (target *lbTarget) HandleConn(conn net.Conn) {
@@ -69,6 +75,8 @@ func (target *lbTarget) HandleConn(conn net.Conn) {
 	target.logger.Printf("proxying connection %s -> %s", conn.RemoteAddr(), upstream.upstream)
 
 	upstreamTarget := tcpproxy.To(upstream.upstream)
+	upstreamTarget.DialTimeout = target.dialTimeout
+	upstreamTarget.KeepAlivePeriod = target.keepAlivePeriod
 	upstreamTarget.OnDialError = func(src net.Conn, dstDialErr error) {
 		src.Close() //nolint: errcheck
 
@@ -109,8 +117,10 @@ func (t *TCP) AddRoute(ipPort string, upstreamAddrs []string, options ...upstrea
 	t.routes[ipPort] = list
 
 	t.Proxy.AddRoute(ipPort, &lbTarget{
-		list:   list,
-		logger: t.Logger,
+		list:            list,
+		logger:          t.Logger,
+		dialTimeout:     t.DialTimeout,
+		keepAlivePeriod: t.KeepAlivePeriod,
 	})
 
 	return nil