commit 5acac28

Send pings, retry connecting after sleep/long pause

 1@@ -412,11 +412,6 @@ func (app *App) tryConnect() (conn net.Conn, err error) {
 2 		return nil, fmt.Errorf("connect: %v", err)
 3 	}
 4 
 5-	if tcpConn, ok := conn.(*net.TCPConn); ok {
 6-		tcpConn.SetKeepAlive(true)
 7-		tcpConn.SetKeepAlivePeriod(15 * time.Second)
 8-	}
 9-
10 	if app.cfg.TLS {
11 		host, _, _ := net.SplitHostPort(addr) // should succeed since net.Dial did.
12 		conn = tls.Client(conn, &tls.Config{

 1@@ -5,6 +5,8 @@ import (
 2 	"fmt"
 3 	"net"
 4 	"strings"
 5+	"sync/atomic"
 6+	"time"
 7 	"unicode"
 8 )
 9 
10@@ -14,6 +16,11 @@ func ChanInOut(conn net.Conn) (in <-chan Message, out chan<- Message) {
11 	in_ := make(chan Message, chanCapacity)
12 	out_ := make(chan Message, chanCapacity)
13 
14+	const keepAlive = 30 * time.Second
15+	const maxRTT = 10 * time.Second
16+	var last atomic.Value
17+	last.Store(time.Now())
18+
19 	go func() {
20 		r := bufio.NewScanner(conn)
21 		for r.Scan() {
22@@ -23,17 +30,45 @@ func ChanInOut(conn net.Conn) (in <-chan Message, out chan<- Message) {
23 			if err != nil {
24 				continue
25 			}
26+			now := time.Now()
27+			last.Store(now)
28+			conn.SetReadDeadline(now.Add(keepAlive + maxRTT))
29 			in_ <- msg
30 		}
31 		close(in_)
32 	}()
33 
34 	go func() {
35-		for msg := range out_ {
36-			// TODO send messages by batches
37-			_, err := fmt.Fprintf(conn, "%s\r\n", msg.String())
38-			if err != nil {
39-				break
40+		t := time.NewTicker(time.Second)
41+		defer t.Stop()
42+	outer:
43+		for {
44+			select {
45+			case msg, ok := <-out_:
46+				if !ok {
47+					break outer
48+				}
49+				last.Store(time.Now())
50+				// TODO send messages by batches
51+				_, err := fmt.Fprintf(conn, "%s\r\n", msg.String())
52+				if err != nil {
53+					break outer
54+				}
55+			case <-t.C:
56+				now := time.Now()
57+				if last.Load().(time.Time).Add(keepAlive).After(now) {
58+					continue
59+				}
60+				if last.Load().(time.Time).Add(keepAlive + maxRTT).Before(now) {
61+					// probably out of sleep, reset connection
62+					conn.Close()
63+					continue
64+				}
65+				last.Store(now)
66+				_, err := fmt.Fprint(conn, "PING _\r\n")
67+				if err != nil {
68+					break outer
69+				}
70 			}
71 		}
72 		_ = conn.Close()