Add TLS support

README.md

@@ -29,7 +29,7 @@ $GOPATH/bin/docker-builder --help
 0. Run`docker-builder --help`
 0. Run `docker-builder help build`
 
-### First, Install `docker-builder`
+### Installing `docker-builder`
 
 #### Easiest
 
@@ -41,11 +41,11 @@ go get github.com/rafecolton/docker-builder
 
 ```bash
 # on Mac OS X
-curl -sL https://github.com/rafecolton/docker-builder/releases/download/v0.9.1/docker-builder-v0.9.1-darwin-amd64 \
+curl -sL https://github.com/rafecolton/docker-builder/releases/download/v0.9.2/docker-builder-v0.9.2-darwin-amd64 \
   -o /usr/local/bin/docker-builder && chmod +x /usr/local/bin/docker-builder
 
 # on Linux, note: you may need sudo
-curl -sL https://github.com/rafecolton/docker-builder/releases/download/v0.9.1/docker-builder-v0.9.1-linux-amd64 \
+curl -sL https://github.com/rafecolton/docker-builder/releases/download/v0.9.2/docker-builder-v0.9.2-linux-amd64 \
   -o /usr/local/bin/docker-builder && chmod +x /usr/local/bin/docker-builder
 ```
 
@@ -56,6 +56,30 @@ curl -sL https://github.com/rafecolton/docker-builder/releases/download/v0.9.1/d
 To build from source, run `make build`.  You may have to install some
 things first, such as `go`
 
+### Using with TLS
+
+If you are using a version of `docker` with TLS enabled (supported in
+`docker` `v1.3.0` and up, enabled by default with `boot2docker`), you
+will need to use `docker-builder` `v0.9.2` or greater.
+
+Additionally, you must set the following environment variables:
+
+```bash
+# all values are the boot2docker defaults
+export DOCKER_CERT_PATH="$HOME/.boot2docker/certs/boot2docker-vm"
+export DOCKER_TLS_VERIFY=1
+export DOCKER_HOST="tcp://127.0.0.1:2376"
+```
+
+**NOTE:** `docker-builder` will automatically set the correct url scheme
+for TLS if you are using port 2376.  If you are using another port and
+wish to enable TLS, you must set the following additional environment
+variable:
+
+```bash
+export DOCKER_HOST_SCHEME="https"
+```
+
 ## Contributing
 
 **Pull requests welcome!**

dclient/dclient.go

@@ -2,7 +2,10 @@ package dclient
 
 import (
 	"fmt"
+	"net"
+	"net/url"
 	"os"
+	"path"
 	"regexp"
 	"sort"
 
@@ -25,19 +28,31 @@ func NewDockerClient(logger *logrus.Logger, shouldBeReal bool) (DockerClient, er
 		}, nil
 	}
 
-	var endpoint string
+	endpoint, err := getEndpoint()
+	if err != nil {
+		return nil, err
+	}
+	tlsVerify := os.Getenv("DOCKER_TLS_VERIFY") != ""
+	certPath := os.Getenv("DOCKER_CERT_PATH")
 
-	defaultHost := os.Getenv("DOCKER_HOST")
+	var dclient *docker.Client
+	if endpoint.Scheme == "https" {
+		if certPath == "" {
+			return nil, fmt.Errorf("Using TLS, but DOCKER_CERT_PATH is empty")
+		}
 
-	if defaultHost == "" {
-		endpoint = "unix:///var/run/docker.sock"
+		cert := path.Join(certPath, "cert.pem")
+		key := path.Join(certPath, "key.pem")
+		ca := ""
+		if tlsVerify {
+			ca = path.Join(certPath, "ca.pem")
+		}
+
+		dclient, err = docker.NewTLSClient(endpoint.String(), cert, key, ca)
 	} else {
-		// tcp endpoints cause a panic with this version of the go/docker library
-		endpoint = defaultHost
+		dclient, err = docker.NewClient(endpoint.String())
 	}
 
-	dclient, err := docker.NewClient(endpoint)
-
 	if err != nil {
 		logger.WithFields(logrus.Fields{
 			"docker_host": endpoint,
@@ -49,7 +64,7 @@ func NewDockerClient(logger *logrus.Logger, shouldBeReal bool) (DockerClient, er
 
 	return &realDockerClient{
 		client: dclient,
-		host:   endpoint,
+		host:   endpoint.String(),
 		Logger: logger,
 	}, nil
 }
@@ -139,3 +154,35 @@ func (rtoo *realDockerClient) PushImage(opts docker.PushImageOptions, auth docke
 func (rtoo *realDockerClient) BuildImage(opts docker.BuildImageOptions) error {
 	return rtoo.client.BuildImage(opts)
 }
+
+// Workaround since DOCKER_HOST typically is tcp:// but we need to vary whether
+// we use HTTP/HTTPS when interacting with the API
+// Can be removed if https://github.com/fsouza/go-dockerclient/issues/173 is
+// resolved
+func getEndpoint() (*url.URL, error) {
+	endpoint := os.Getenv("DOCKER_HOST")
+	if endpoint == "" {
+		endpoint = "unix:///var/run/docker.sock"
+	}
+
+	u, err := url.Parse(endpoint)
+	if err != nil {
+		return nil, fmt.Errorf("couldn't parse endpoint %s as URL", endpoint)
+	}
+	if u.Scheme == "tcp" {
+		_, port, err := net.SplitHostPort(u.Host)
+		if err != nil {
+			return nil, fmt.Errorf("error parsing %s for port", u.Host)
+		}
+
+		// Only reliable way to determine if we should be using HTTPS appears to be via port
+		if os.Getenv("DOCKER_HOST_SCHEME") != "" {
+			u.Scheme = os.Getenv("DOCKER_HOST_SCHEME")
+		} else if port == "2376" {
+			u.Scheme = "https"
+		} else {
+			u.Scheme = "http"
+		}
+	}
+	return u, nil
+}