From 069966d55a0f9ee7d6e1b6f084d54ce8a331f7f0 Mon Sep 17 00:00:00 2001
From: Brian Tiger Chow <brian.holderchow@gmail.com>
Date: Thu, 4 Dec 2014 21:31:38 -0800
Subject: [PATCH] ping WIP

License: MIT
Signed-off-by: Brian Tiger Chow <brian@perfmode.com>

Conflicts:
	core/commands/root.go

begin ping command, WIP

finish initial ping implementation
---
 core/commands/ping.go              | 108 +++++++++++++++++++++++++++++
 core/commands/root.go              |   1 +
 routing/mock/centralized_client.go |   4 ++
 routing/routing.go                 |   3 +
 4 files changed, 116 insertions(+)
 create mode 100644 core/commands/ping.go

diff --git a/core/commands/ping.go b/core/commands/ping.go
new file mode 100644
index 000000000..9eb039f1f
--- /dev/null
+++ b/core/commands/ping.go
@@ -0,0 +1,108 @@
+package commands
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"time"
+
+	cmds "github.com/jbenet/go-ipfs/commands"
+	peer "github.com/jbenet/go-ipfs/p2p/peer"
+	u "github.com/jbenet/go-ipfs/util"
+
+	context "github.com/jbenet/go-ipfs/Godeps/_workspace/src/code.google.com/p/go.net/context"
+)
+
+type PingResult struct {
+	Success bool
+	Time    time.Duration
+}
+
+var PingCmd = &cmds.Command{
+	Helptext: cmds.HelpText{
+		Tagline: "send echo request packets to IPFS hosts",
+		Synopsis: `
+ipfs ping <peer.ID> - Send pings to a peer using the routing system to discover its address
+`,
+		ShortDescription: `
+ipfs ping is a tool to find a node (in the routing system),
+send pings, wait for pongs, and print out round-trip latency information.
+`,
+	},
+	Arguments: []cmds.Argument{
+		cmds.StringArg("peer-id", true, true, "ID of peer to ping"),
+	},
+	Marshalers: cmds.MarshalerMap{
+		cmds.Text: func(res cmds.Response) (io.Reader, error) {
+			outChan, ok := res.Output().(chan interface{})
+			if !ok {
+				return nil, u.ErrCast()
+			}
+
+			marshal := func(v interface{}) (io.Reader, error) {
+				obj, ok := v.(*PingResult)
+				if !ok {
+					return nil, u.ErrCast()
+				}
+
+				buf := new(bytes.Buffer)
+				if obj.Success {
+					fmt.Fprintf(buf, "Pong took %.2fms\n", obj.Time.Seconds()*1000)
+				} else {
+					fmt.Fprintf(buf, "Pong failed\n")
+				}
+				return buf, nil
+			}
+
+			return &cmds.ChannelMarshaler{
+				Channel:   outChan,
+				Marshaler: marshal,
+			}, nil
+		},
+	},
+	Run: func(req cmds.Request) (interface{}, error) {
+		n, err := req.Context().GetNode()
+		if err != nil {
+			return nil, err
+		}
+
+		if !n.OnlineMode() {
+			return nil, errNotOnline
+		}
+
+		peerID, err := peer.IDB58Decode("QmaCpDMGvV2BGHeYERUEnRQAwe3N8SzbUtfsmvsqQLuvuJ")
+		if err != nil {
+			return nil, err
+		}
+		const kPingTimeout = 10 * time.Second
+		ctx, _ := context.WithTimeout(context.Background(), kPingTimeout)
+		p, err := n.Routing.FindPeer(ctx, peerID)
+		if err != nil {
+			return nil, err
+		}
+
+		outChan := make(chan interface{})
+
+		go func() {
+			defer close(outChan)
+			for i := 0; i < 10; i++ {
+				ctx, _ = context.WithTimeout(context.Background(), kPingTimeout)
+				before := time.Now()
+				err := n.Routing.Ping(ctx, p.ID)
+				if err != nil {
+					outChan <- &PingResult{}
+					break
+				}
+				took := time.Now().Sub(before)
+				outChan <- &PingResult{
+					Success: true,
+					Time:    took,
+				}
+				time.Sleep(time.Second)
+			}
+		}()
+
+		return outChan, nil
+	},
+	Type: PingResult{},
+}
diff --git a/core/commands/root.go b/core/commands/root.go
index 9ab6185a1..7318b5a19 100644
--- a/core/commands/root.go
+++ b/core/commands/root.go
@@ -81,6 +81,7 @@ var rootSubcommands = map[string]*cmds.Command{
 	"pin":       PinCmd,
 	"refs":      RefsCmd,
 	"swarm":     SwarmCmd,
+	"ping":      PingCmd,
 	"update":    UpdateCmd,
 	"version":   VersionCmd,
 }
diff --git a/routing/mock/centralized_client.go b/routing/mock/centralized_client.go
index 2aeafe026..da8e39692 100644
--- a/routing/mock/centralized_client.go
+++ b/routing/mock/centralized_client.go
@@ -79,4 +79,8 @@ func (c *client) Provide(_ context.Context, key u.Key) error {
 	return c.server.Announce(info, key)
 }
 
+func (c *client) Ping(ctx context.Context, p peer.ID) error {
+	return nil
+}
+
 var _ routing.IpfsRouting = &client{}
diff --git a/routing/routing.go b/routing/routing.go
index 1fbd79d25..934a00c41 100644
--- a/routing/routing.go
+++ b/routing/routing.go
@@ -36,4 +36,7 @@ type IpfsRouting interface {
 	// FindPeer searches for a peer with given ID, returns a peer.PeerInfo
 	// with relevant addresses.
 	FindPeer(context.Context, peer.ID) (peer.PeerInfo, error)
+
+	// Ping a peer, log the time it took
+	Ping(context.Context, peer.ID) error
 }