Integration tests for --bridge daemon flag

Signed-off-by: Madhu Venugopal <madhu@docker.com>

integration-cli/docker_cli_daemon_test.go

@@ -6,6 +6,7 @@ import (
 	"encoding/json"
 	"fmt"
 	"io/ioutil"
+	"net"
 	"os"
 	"os/exec"
 	"path/filepath"
@@ -447,6 +448,46 @@ func (s *DockerDaemonSuite) TestDaemonExitOnFailure(c *check.C) {
 	}
 }
 
+func (s *DockerDaemonSuite) TestDaemonBridgeExternal(c *check.C) {
+	d := s.d
+	err := d.Start("--bridge", "nosuchbridge")
+	c.Assert(err, check.Not(check.IsNil), check.Commentf("--bridge option with an invalid bridge should cause the daemon to fail"))
+
+	bridgeName := "external-bridge"
+	bridgeIp := "192.169.1.1/24"
+	_, bridgeIPNet, _ := net.ParseCIDR(bridgeIp)
+
+	args := []string{"link", "add", "name", bridgeName, "type", "bridge"}
+	ipLinkCmd := exec.Command("ip", args...)
+	_, _, _, err = runCommandWithStdoutStderr(ipLinkCmd)
+	c.Assert(err, check.IsNil)
+
+	ifCfgCmd := exec.Command("ifconfig", bridgeName, bridgeIp, "up")
+	_, _, _, err = runCommandWithStdoutStderr(ifCfgCmd)
+	c.Assert(err, check.IsNil)
+
+	err = d.StartWithBusybox("--bridge", bridgeName)
+	c.Assert(err, check.IsNil)
+
+	ipTablesSearchString := bridgeIPNet.String()
+	ipTablesCmd := exec.Command("iptables", "-t", "nat", "-nvL")
+	out, _, err := runCommandWithOutput(ipTablesCmd)
+	c.Assert(err, check.IsNil)
+
+	c.Assert(strings.Contains(out, ipTablesSearchString), check.Equals, true,
+		check.Commentf("iptables output should have contained %q, but was %q",
+			ipTablesSearchString, out))
+
+	_, err = d.Cmd("run", "-d", "--name", "ExtContainer", "busybox", "top")
+	c.Assert(err, check.IsNil)
+
+	containerIp := d.findContainerIP(c, "ExtContainer")
+	ip := net.ParseIP(containerIp)
+	c.Assert(bridgeIPNet.Contains(ip), check.Equals, true,
+		check.Commentf("Container IP-Address must be in the same subnet range : %s",
+			containerIp))
+}
+
 func (s *DockerDaemonSuite) TestDaemonUlimitDefaults(c *check.C) {
 	testRequires(c, NativeExecDriver)
 

integration-cli/docker_utils.go

@@ -570,8 +570,9 @@ func dockerCmdInDirWithTimeout(timeout time.Duration, path string, args ...strin
 	return out, status, err
 }
 
-func findContainerIP(c *check.C, id string) string {
-	cmd := exec.Command(dockerBinary, "inspect", "--format='{{ .NetworkSettings.IPAddress }}'", id)
+func findContainerIP(c *check.C, id string, vargs ...string) string {
+	args := append(vargs, "inspect", "--format='{{ .NetworkSettings.IPAddress }}'", id)
+	cmd := exec.Command(dockerBinary, args...)
 	out, _, err := runCommandWithOutput(cmd)
 	if err != nil {
 		c.Fatal(err, out)
@@ -580,6 +581,10 @@ func findContainerIP(c *check.C, id string) string {
 	return strings.Trim(out, " \r\n'")
 }
 
+func (d *Daemon) findContainerIP(c *check.C, id string) string {
+	return findContainerIP(c, id, "--host", d.sock())
+}
+
 func getContainerCount() (int, error) {
 	const containers = "Containers:"