From e698770d40637a97537c30abb46cab3883545017 Mon Sep 17 00:00:00 2001
From: Alessandro Boch <aboch@docker.com>
Date: Wed, 1 Jul 2015 09:54:26 -0700
Subject: [PATCH] Stats API to retrieve nw stats from libnetwork - Container
 networking statistics are no longer   retrievable from libcontainer after the
 introduction   of libnetwork. This change adds the missing code   for docker
 daemon to retireve the nw stats from   Endpoint.

Signed-off-by: Alessandro Boch <aboch@docker.com>
---
 daemon/stats.go                          | 48 ++++++++++++++++++++++++
 integration-cli/docker_api_stats_test.go | 40 ++++++++++++++++++++
 2 files changed, 88 insertions(+)

diff --git a/daemon/stats.go b/daemon/stats.go
index 6a49172fc..e21cad68d 100644
--- a/daemon/stats.go
+++ b/daemon/stats.go
@@ -8,6 +8,7 @@ import (
 	"github.com/docker/docker/daemon/execdriver"
 	"github.com/docker/libcontainer"
 	"github.com/docker/libcontainer/cgroups"
+	"github.com/docker/libnetwork/sandbox"
 )
 
 func (daemon *Daemon) ContainerStats(name string, stream bool, out io.Writer) error {
@@ -19,6 +20,10 @@ func (daemon *Daemon) ContainerStats(name string, stream bool, out io.Writer) er
 	var preCpuStats types.CpuStats
 	getStat := func(v interface{}) *types.Stats {
 		update := v.(*execdriver.ResourceStats)
+		// Retrieve the nw statistics from libnetwork and inject them in the Stats
+		if nwStats, err := daemon.getNetworkStats(name); err == nil {
+			update.Stats.Interfaces = nwStats
+		}
 		ss := convertToAPITypes(update.Stats)
 		ss.PreCpuStats = preCpuStats
 		ss.MemoryStats.Limit = uint64(update.MemoryLimit)
@@ -118,3 +123,46 @@ func copyBlkioEntry(entries []cgroups.BlkioStatEntry) []types.BlkioStatEntry {
 	}
 	return out
 }
+
+func (daemon *Daemon) getNetworkStats(name string) ([]*libcontainer.NetworkInterface, error) {
+	var list []*libcontainer.NetworkInterface
+
+	c, err := daemon.Get(name)
+	if err != nil {
+		return list, err
+	}
+
+	nw, err := daemon.netController.NetworkByID(c.NetworkSettings.NetworkID)
+	if err != nil {
+		return list, err
+	}
+	ep, err := nw.EndpointByID(c.NetworkSettings.EndpointID)
+	if err != nil {
+		return list, err
+	}
+
+	stats, err := ep.Statistics()
+	if err != nil {
+		return list, err
+	}
+
+	// Convert libnetwork nw stats into libcontainer nw stats
+	for ifName, ifStats := range stats {
+		list = append(list, convertLnNetworkStats(ifName, ifStats))
+	}
+
+	return list, nil
+}
+
+func convertLnNetworkStats(name string, stats *sandbox.InterfaceStatistics) *libcontainer.NetworkInterface {
+	n := &libcontainer.NetworkInterface{Name: name}
+	n.RxBytes = stats.RxBytes
+	n.RxPackets = stats.RxPackets
+	n.RxErrors = stats.RxErrors
+	n.RxDropped = stats.RxDropped
+	n.TxBytes = stats.TxBytes
+	n.TxPackets = stats.TxPackets
+	n.TxErrors = stats.TxErrors
+	n.TxDropped = stats.TxDropped
+	return n
+}
diff --git a/integration-cli/docker_api_stats_test.go b/integration-cli/docker_api_stats_test.go
index 6a143fed1..09d0be6f4 100644
--- a/integration-cli/docker_api_stats_test.go
+++ b/integration-cli/docker_api_stats_test.go
@@ -3,6 +3,8 @@ package main
 import (
 	"encoding/json"
 	"fmt"
+	"os/exec"
+	"strconv"
 	"strings"
 
 	"github.com/docker/docker/api/types"
@@ -33,3 +35,41 @@ func (s *DockerSuite) TestCliStatsNoStreamGetCpu(c *check.C) {
 		c.Fatalf("docker stats with no-stream get cpu usage failed: was %v", cpuPercent)
 	}
 }
+
+func (s *DockerSuite) TestApiNetworkStats(c *check.C) {
+	// Run container for 30 secs
+	out, _ := dockerCmd(c, "run", "-d", "busybox", "top")
+	id := strings.TrimSpace(out)
+	err := waitRun(id)
+	c.Assert(err, check.IsNil)
+
+	// Retrieve the container address
+	contIP := findContainerIP(c, id)
+	numPings := 10
+
+	// Get the container networking stats before and after pinging the container
+	nwStatsPre := getNetworkStats(c, id)
+	_, err = exec.Command("ping", contIP, "-c", strconv.Itoa(numPings)).Output()
+	c.Assert(err, check.IsNil)
+	nwStatsPost := getNetworkStats(c, id)
+
+	// Verify the stats contain at least the expected number of packets (account for ARP)
+	expRxPkts := 1 + nwStatsPre.RxPackets + uint64(numPings)
+	expTxPkts := 1 + nwStatsPre.TxPackets + uint64(numPings)
+	c.Assert(nwStatsPost.TxPackets >= expTxPkts, check.Equals, true,
+		check.Commentf("Reported less TxPackets than expected. Expected >= %d. Found %d", expTxPkts, nwStatsPost.TxPackets))
+	c.Assert(nwStatsPost.RxPackets >= expRxPkts, check.Equals, true,
+		check.Commentf("Reported less Txbytes than expected. Expected >= %d. Found %d", expRxPkts, nwStatsPost.RxPackets))
+}
+
+func getNetworkStats(c *check.C, id string) types.Network {
+	var st *types.Stats
+
+	_, body, err := sockRequestRaw("GET", fmt.Sprintf("/containers/%s/stats?stream=false", id), nil, "")
+	c.Assert(err, check.IsNil)
+
+	err = json.NewDecoder(body).Decode(&st)
+	c.Assert(err, check.IsNil)
+
+	return st.Network
+}