Add integration test for hairpin nat

Docker-DCO-1.1-Signed-off-by: Guillaume J. Charmes <guillaume@charmes.net> (github: creack)

integration-cli/docker_cli_nat_test.go

@@ -0,0 +1,84 @@
+package main
+
+import (
+	"encoding/json"
+	"fmt"
+	"github.com/dotcloud/docker/runtime"
+	"net"
+	"os/exec"
+	"path/filepath"
+	"testing"
+)
+
+func TestNetworkNat(t *testing.T) {
+	ncPath, err := exec.LookPath("nc")
+	if err != nil {
+		t.Skip("Test not running with `make test`. Netcat not found: %s", err)
+	}
+	ncPath, err = filepath.EvalSymlinks(ncPath)
+	if err != nil {
+		t.Fatalf("Error resolving netcat symlink: %s", err)
+	}
+	iface, err := net.InterfaceByName("eth0")
+	if err != nil {
+		t.Skip("Test not running with `make test`. Interface eth0 not found: %s", err)
+	}
+
+	ifaceAddrs, err := iface.Addrs()
+	if err != nil || len(ifaceAddrs) == 0 {
+		t.Fatalf("Error retrieving addresses for eth0: %v (%d addresses)", err, len(ifaceAddrs))
+	}
+
+	ifaceIp, _, err := net.ParseCIDR(ifaceAddrs[0].String())
+	if err != nil {
+		t.Fatalf("Error retrieving the up for eth0: %s", err)
+	}
+
+	runCmd := exec.Command(dockerBinary, "run", "-d",
+		"-v", ncPath+":/bin/nc",
+		"-v", "/lib/x86_64-linux-gnu/libc.so.6:/lib/libc.so.6", "-v", "/lib/x86_64-linux-gnu/libresolv.so.2:/lib/libresolv.so.2", "-v", "/lib/x86_64-linux-gnu/libbsd.so.0:/lib/libbsd.so.0", "-v", "/lib/x86_64-linux-gnu/ld-linux-x86-64.so.2:/lib/ld-linux-x86-64.so.2",
+		"-p", "8080", "busybox", "/bin/nc", "-lp", "8080")
+	out, _, err := runCommandWithOutput(runCmd)
+	errorOut(err, t, fmt.Sprintf("run1 failed with errors: %v (%s)", err, out))
+
+	cleanedContainerID := stripTrailingCharacters(out)
+
+	inspectCmd := exec.Command(dockerBinary, "inspect", cleanedContainerID)
+	inspectOut, _, err := runCommandWithOutput(inspectCmd)
+	errorOut(err, t, fmt.Sprintf("out should've been a container id: %v %v", inspectOut, err))
+
+	containers := []*runtime.Container{}
+	if err := json.Unmarshal([]byte(inspectOut), &containers); err != nil {
+		t.Fatalf("Error inspecting the container: %s", err)
+	}
+	if len(containers) != 1 {
+		t.Fatalf("Unepexted container count. Expected 0, recieved: %d", len(containers))
+	}
+
+	port8080, exists := containers[0].NetworkSettings.Ports["8080/tcp"]
+	if !exists || len(port8080) == 0 {
+		t.Fatal("Port 8080/tcp not found in NetworkSettings")
+	}
+
+	runCmd = exec.Command(dockerBinary, "run",
+		"-v", ncPath+":/bin/nc",
+		"-v", "/lib/x86_64-linux-gnu/libc.so.6:/lib/libc.so.6", "-v", "/lib/x86_64-linux-gnu/libresolv.so.2:/lib/libresolv.so.2", "-v", "/lib/x86_64-linux-gnu/libbsd.so.0:/lib/libbsd.so.0", "-v", "/lib/x86_64-linux-gnu/ld-linux-x86-64.so.2:/lib/ld-linux-x86-64.so.2",
+		"-p", "8080", "busybox", "sh", "-c", fmt.Sprintf("echo hello world | /bin/nc -w 30 %s %s", ifaceIp, port8080[0].HostPort))
+	out, _, err = runCommandWithOutput(runCmd)
+	errorOut(err, t, fmt.Sprintf("run2 failed with errors: %v (%s)", err, out))
+
+	runCmd = exec.Command(dockerBinary, "logs", cleanedContainerID)
+	out, _, err = runCommandWithOutput(runCmd)
+	errorOut(err, t, fmt.Sprintf("failed to retrieve logs for container: %v %v", cleanedContainerID, err))
+
+	if expected := "hello world\n"; out != expected {
+		t.Fatalf("Unexpected output. Expected: %s, recieved: -->%s<--", expected, out)
+	}
+
+	killCmd := exec.Command(dockerBinary, "kill", cleanedContainerID)
+	out, _, err = runCommandWithOutput(killCmd)
+	errorOut(err, t, fmt.Sprintf("failed to kill container: %v %v", out, err))
+	deleteAllContainers()
+
+	logDone("network - make sure nat works through the host")
+}