Added cli SNI integration test

Signed-off-by: Federico Gimenez <fgimenez@coit.es>

integration-cli/docker_cli_sni_test.go

@@ -0,0 +1,43 @@
+package main
+
+import (
+	"fmt"
+	"io/ioutil"
+	"log"
+	"net/http"
+	"net/http/httptest"
+	"net/url"
+	"os/exec"
+	"strings"
+
+	"github.com/go-check/check"
+)
+
+func (s *DockerSuite) TestClientSetsTLSServerName(c *check.C) {
+	// there may be more than one hit to the server for each registry request
+	serverNameReceived := []string{}
+	var serverName string
+
+	virtualHostServer := httptest.NewTLSServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		serverNameReceived = append(serverNameReceived, r.TLS.ServerName)
+	}))
+	defer virtualHostServer.Close()
+	// discard TLS handshake errors written by default to os.Stderr
+	virtualHostServer.Config.ErrorLog = log.New(ioutil.Discard, "", 0)
+
+	u, err := url.Parse(virtualHostServer.URL)
+	c.Assert(err, check.IsNil)
+	hostPort := u.Host
+	serverName = strings.Split(hostPort, ":")[0]
+
+	repoName := fmt.Sprintf("%v/dockercli/image:latest", hostPort)
+	cmd := exec.Command(dockerBinary, "pull", repoName)
+	cmd.Run()
+
+	// check that the fake server was hit at least once
+	c.Assert(len(serverNameReceived) > 0, check.Equals, true)
+	// check that for each hit the right server name was received
+	for _, item := range serverNameReceived {
+		c.Check(item, check.Equals, serverName)
+	}
+}