@@ -24,6 +24,7 @@ import (

 	"net/http/httputil"

 	"net/url"

 	"os"

+	"os/exec"

 	gosignal "os/signal"

 	"path"

 	"reflect"

@@ -158,6 +159,8 @@ func (cli *DockerCli) CmdBuild(args ...string) error {

 		err      error

 	)

+	_, err = exec.LookPath("git")

+	hasGit := err == nil

 	if cmd.Arg(0) == "-" {

 		// As a special case, 'docker build -' will build from an empty context with the

 		// contents of stdin as a Dockerfile

@@ -166,17 +169,34 @@ func (cli *DockerCli) CmdBuild(args ...string) error {

 			return err

 		}

 		context, err = archive.Generate("Dockerfile", string(dockerfile))

-	} else if utils.IsURL(cmd.Arg(0)) || utils.IsGIT(cmd.Arg(0)) {

+	} else if utils.IsURL(cmd.Arg(0)) && (!utils.IsGIT(cmd.Arg(0)) || !hasGit) {

 		isRemote = true

 	} else {

-		if _, err := os.Stat(cmd.Arg(0)); err != nil {

+		root := cmd.Arg(0)

+		if utils.IsGIT(root) {

+			remoteURL := cmd.Arg(0)

+			if !strings.HasPrefix(remoteURL, "git://") && !strings.HasPrefix(remoteURL, "git@") && !utils.IsURL(remoteURL) {

+				remoteURL = "https://" + remoteURL

+			}

+

+			root, err = ioutil.TempDir("", "docker-build-git")

+			if err != nil {

+				return err

+			}

+			defer os.RemoveAll(root)

+

+			if output, err := exec.Command("git", "clone", "--recursive", remoteURL, root).CombinedOutput(); err != nil {

+				return fmt.Errorf("Error trying to use git: %s (%s)", err, output)

+			}

+		}

+		if _, err := os.Stat(root); err != nil {

 			return err

 		}

-		filename := path.Join(cmd.Arg(0), "Dockerfile")

+		filename := path.Join(root, "Dockerfile")

 		if _, err = os.Stat(filename); os.IsNotExist(err) {

 			return fmt.Errorf("no Dockerfile found in %s", cmd.Arg(0))

 		}

-		context, err = archive.Tar(cmd.Arg(0), archive.Uncompressed)

+		context, err = archive.Tar(root, archive.Uncompressed)

 	}

 	var body io.Reader

 	// Setup an upload progress bar

@@ -203,12 +203,16 @@ Examples:

       --no-cache: Do not use the cache when building the image.

       --rm=true: Remove intermediate containers after a successful build

-The files at ``PATH`` or ``URL`` are called the "context" of the build. The

-build process may refer to any of the files in the context, for example when

-using an :ref:`ADD <dockerfile_add>` instruction.  When a single ``Dockerfile``

-is given as ``URL``, then no context is set.  When a Git repository is set as

-``URL``, then the repository is used as the context. Git repositories are

-cloned with their submodules (`git clone --recursive`).

+The files at ``PATH`` or ``URL`` are called the "context" of the build.

+The build process may refer to any of the files in the context, for example when

+using an :ref:`ADD <dockerfile_add>` instruction.

+When a single ``Dockerfile`` is given as ``URL``, then no context is set.

+

+When a Git repository is set as ``URL``, then the repository is used as the context. 

+The Git repository is cloned with its submodules (`git clone --recursive`).

+A fresh git clone occurs in a temporary directory on your local host, and then this 

+is sent to the Docker daemon as the context. 

+This way, your local user credentials and vpn's etc can be used to access private repositories

 .. _cli_build_examples:

@@ -714,7 +714,7 @@ func IsURL(str string) bool {

 }

 func IsGIT(str string) bool {

-	return strings.HasPrefix(str, "git://") || strings.HasPrefix(str, "github.com/")

+	return strings.HasPrefix(str, "git://") || strings.HasPrefix(str, "github.com/") || strings.HasPrefix(str, "git@github.com:") || (strings.HasSuffix(str, ".git") && IsURL(str))

 }

 // GetResolvConf opens and read the content of /etc/resolv.conf.