circolog/cmd/circolog-tail/main.go

87 rivejä
1,8 KiB
Go

package main
import (
"flag"
"fmt"
"log"
"net"
"net/url"
"os"
"os/signal"
"time"
"github.com/gorilla/websocket"
)
func main() {
addr := flag.String("addr", "localhost:9080", "http service address")
querySocket := flag.String("socket", "", "Path to a unix domain socket for the HTTP server")
flag.Parse()
interrupt := make(chan os.Signal, 1)
signal.Notify(interrupt, os.Interrupt)
var d *websocket.Dialer
u := url.URL{Scheme: "ws",
Host: *addr, // ignored in case of -socket; see the Dialer below
Path: "/ws",
}
if *querySocket != "" {
d = &websocket.Dialer{
NetDial: func(network, addr string) (net.Conn, error) {
return net.Dial("unix", *querySocket)
},
HandshakeTimeout: 45 * time.Second, // same as DefaultDialer
}
log.Printf("connecting to %s", *querySocket)
} else {
d = websocket.DefaultDialer
log.Printf("connecting to %s", *addr)
}
c, _, err := d.Dial(u.String(), nil)
if err != nil {
log.Fatal("dial:", err)
}
defer c.Close()
log.Println("connected!", u.String())
done := make(chan struct{})
go func() {
defer close(done)
for {
_, message, err := c.ReadMessage()
if err != nil {
log.Println("close:", err)
return
}
fmt.Println(string(message))
}
}()
for {
select {
case <-done:
return
case <-interrupt:
log.Println("interrupt")
// Cleanly close the connection by sending a close message and then waiting (with timeout) for the
// server to close the connection.
err := c.WriteMessage(websocket.CloseMessage, websocket.FormatCloseMessage(websocket.CloseNormalClosure, ""))
if err != nil {
log.Println("write close:", err)
return
}
select {
case <-done:
log.Println("Successfully close")
case <-time.After(1 * time.Second):
log.Println("Forced close")
}
return
}
}
}