Merge pull request #267 from moul/dev/moul/wip

Add ping

README.md

@@ -561,6 +561,7 @@ AUTHOR(S):
    Manfred Touron <https://github.com/moul/advanced-ssh-config>
 
 COMMANDS:
+   ping          Send packets to the SSH server and display statistics
    info          Display system-wide information
    config        Manage ssh and assh configuration
    sockets       Manage control sockets
@@ -713,6 +714,23 @@ Create a master control sockets.
 $ assh sockets master
 ```
 
+#### `assh ping`
+
+Send packets to the SSH server and display stats.
+
+```console
+$ assh ping -c 4 localhost
+PING localhost (127.0.0.1) PORT 22 (ssh) PROTO tcp
+Connected to 127.0.0.1: seq=0 time=321µs protocol=tcp port=22
+Connected to 127.0.0.1: seq=1 time=501µs protocol=tcp port=22
+Connected to 127.0.0.1: seq=2 time=550µs protocol=tcp port=22
+Connected to 127.0.0.1: seq=3 time=641µs protocol=tcp port=22
+
+--- localhost assh ping statistics ---
+4 packets transmitted, 4 packets received, 0.00% packet loss
+round-trip min/avg/max = 321µs/503.25µs/641µs
+```
+
 ## Install
 
 Get the latest version using GO (recommended way):
@@ -827,6 +845,7 @@ Host *
 * Add possibility to disable automatic configuration rewrite ([#239](https://github.com/moul/advanced-ssh-config/issues/239))
 * Add `BeforeConfigWrite` and `AfterConfigWrite` new hooks ([#239](https://github.com/moul/advanced-ssh-config/issues/239))
 * Generate full assh binary path in ~/.ssh/config ([#148](https://github.com/moul/advanced-ssh-config/issues/148))
+* Initial version of `assh ping` command
 
 [Full commits list](https://github.com/moul/advanced-ssh-config/compare/v2.6.0...master)
 

pkg/commands/commands.go

@@ -45,6 +45,35 @@ var Commands = []cli.Command{
 			},
 		},
 	},
+	{
+		Name:   "ping",
+		Usage:  "Send packets to the SSH server and display statistics",
+		Action: cmdPing,
+		Flags: []cli.Flag{
+			cli.IntFlag{
+				Name:  "port, p",
+				Usage: "SSH destination port",
+			},
+			cli.UintFlag{
+				Name:  "count, c",
+				Usage: "Stop after sending 'count' packets",
+			},
+			cli.Float64Flag{
+				Name:  "wait, i",
+				Usage: "Wait 'wait' seconds between sending each packet",
+				Value: 1,
+			},
+			cli.BoolFlag{
+				Name:  "o",
+				Usage: "Exit successfully after receiving one reply packet",
+			},
+			cli.Float64Flag{
+				Name:  "waittime, W",
+				Usage: "Time in seconds to wait for a reply for each packet sent",
+				Value: 1,
+			},
+		},
+	},
 	/*
 		{
 			Name:        "info",

pkg/commands/ping.go

@@ -0,0 +1,92 @@
+package commands
+
+import (
+	"fmt"
+	"net"
+	"time"
+
+	"github.com/urfave/cli"
+
+	"github.com/moul/advanced-ssh-config/pkg/config"
+	. "github.com/moul/advanced-ssh-config/pkg/logger"
+)
+
+func cmdPing(c *cli.Context) error {
+	if len(c.Args()) < 1 {
+		Logger.Fatalf("assh: \"ping\" requires exactly 1 argument. See 'assh ping --help'.")
+	}
+
+	conf, err := config.Open(c.GlobalString("config"))
+	if err != nil {
+		Logger.Fatalf("Cannot open configuration file: %v", err)
+	}
+	if err = conf.LoadKnownHosts(); err != nil {
+		Logger.Debugf("Failed to load assh known_hosts: %v", err)
+	}
+	target := c.Args()[0]
+	host, err := computeHost(target, c.Int("port"), conf)
+	if err != nil {
+		Logger.Fatalf("Cannot get host '%s': %v", target, err)
+	}
+
+	if len(host.Gateways) > 0 {
+		Logger.Fatalf("assh \"ping\" is not working with gateways (yet).")
+	}
+	if host.ProxyCommand != "" {
+		Logger.Fatalf("assh \"ping\" is not working with custom ProxyCommand (yet).")
+	}
+
+	portName := "ssh"
+	if host.Port != "22" {
+		// fixme: resolve port name
+		portName = "unknown"
+	}
+	proto := "tcp"
+	fmt.Printf("PING %s (%s) PORT %s (%s) PROTO %s\n", target, host.HostName, host.Port, portName, proto)
+	dest := fmt.Sprintf("%s:%s", host.HostName, host.Port)
+	count := c.Uint("count")
+	transmittedPackets := 0
+	receivedPackets := 0
+	minRoundtrip := time.Duration(0)
+	maxRoundtrip := time.Duration(0)
+	totalRoundtrip := time.Duration(0)
+	for seq := uint(0); count == 0 || seq < count; seq++ {
+		if seq > 0 {
+			time.Sleep(time.Duration(c.Float64("wait")) * time.Second)
+		}
+		start := time.Now()
+		conn, err := net.DialTimeout(proto, dest, time.Second*time.Duration(c.Float64("waittime")))
+		transmittedPackets++
+		duration := time.Now().Sub(start)
+		totalRoundtrip += duration
+		if minRoundtrip == 0 || minRoundtrip > duration {
+			minRoundtrip = duration
+		}
+		if maxRoundtrip < duration {
+			maxRoundtrip = duration
+		}
+		if err == nil {
+			defer conn.Close()
+		}
+		if err == nil {
+			receivedPackets++
+			fmt.Printf("Connected to %s: seq=%d time=%v protocol=%s port=%s\n", host.HostName, seq, duration, proto, host.Port)
+			if c.Bool("o") {
+				goto stats
+			}
+		} else {
+			// FIXME: switch on error type
+			fmt.Printf("Request timeout for seq %d (%v)\n", seq, err)
+		}
+	}
+
+	// FIXME: catch Ctrl+C
+
+stats:
+	fmt.Printf("\n--- %s assh ping statistics ---\n", target)
+	packetLossRatio := float64(transmittedPackets-receivedPackets) / float64(transmittedPackets) * 100
+	fmt.Printf("%d packets transmitted, %d packets received, %.2f%% packet loss\n", transmittedPackets, receivedPackets, packetLossRatio)
+	avgRoundtrip := totalRoundtrip / time.Duration(transmittedPackets)
+	fmt.Printf("round-trip min/avg/max = %v/%v/%v\n", minRoundtrip, avgRoundtrip, maxRoundtrip)
+	return nil
+}