diff --git a/pkg/httputils/httputils.go b/pkg/httputils/httputils.go
index c586c0232e..0fd90ea3b1 100644
--- a/pkg/httputils/httputils.go
+++ b/pkg/httputils/httputils.go
@@ -5,11 +5,15 @@ import (
 	"fmt"
 	"net/http"
 	"regexp"
-	"strings"
 
 	"github.com/docker/docker/pkg/jsonmessage"
 )
 
+var (
+	headerRegexp     = regexp.MustCompile(`^(?:(.+)/(.+))\s\((.+)\).*$`)
+	errInvalidHeader = errors.New("Bad header, should be in format `docker/version (platform)`")
+)
+
 // Download requests a given URL and returns an io.Reader.
 func Download(url string) (resp *http.Response, err error) {
 	if resp, err = http.Get(url); err != nil {
@@ -39,21 +43,13 @@ type ServerHeader struct {
 // ParseServerHeader extracts pieces from an HTTP server header
 // which is in the format "docker/version (os)" eg docker/1.8.0-dev (windows).
 func ParseServerHeader(hdr string) (*ServerHeader, error) {
-	re := regexp.MustCompile(`.*\((.+)\).*$`)
-	r := &ServerHeader{}
-	if matches := re.FindStringSubmatch(hdr); matches != nil {
-		r.OS = matches[1]
-		parts := strings.Split(hdr, "/")
-		if len(parts) != 2 {
-			return nil, errors.New("Bad header: '/' missing")
-		}
-		r.App = parts[0]
-		v := strings.Split(parts[1], " ")
-		if len(v) != 2 {
-			return nil, errors.New("Bad header: Expected single space")
-		}
-		r.Ver = v[0]
-		return r, nil
+	matches := headerRegexp.FindStringSubmatch(hdr)
+	if len(matches) != 4 {
+		return nil, errInvalidHeader
 	}
-	return nil, errors.New("Bad header: Failed regex match")
+	return &ServerHeader{
+		App: matches[1],
+		Ver: matches[2],
+		OS:  matches[3],
+	}, nil
 }
diff --git a/pkg/httputils/httputils_test.go b/pkg/httputils/httputils_test.go
new file mode 100644
index 0000000000..61e98ba0b4
--- /dev/null
+++ b/pkg/httputils/httputils_test.go
@@ -0,0 +1,59 @@
+package httputils
+
+import "testing"
+
+func TestDownload(t *testing.T) {
+	_, err := Download("http://docker.com")
+
+	if err != nil {
+		t.Fatalf("Expected error to not exist when Download(http://docker.com)")
+	}
+
+	// Expected status code = 404
+	if _, err = Download("http://docker.com/abc1234567"); err == nil {
+		t.Fatalf("Expected error to exist when Download(http://docker.com/abc1234567)")
+	}
+}
+
+func TestNewHTTPRequestError(t *testing.T) {
+	errorMessage := "Some error message"
+	httpResponse, _ := Download("http://docker.com")
+	if err := NewHTTPRequestError(errorMessage, httpResponse); err.Error() != errorMessage {
+		t.Fatalf("Expected err to equal error Message")
+	}
+}
+
+func TestParseServerHeader(t *testing.T) {
+	if _, err := ParseServerHeader("bad header"); err != errInvalidHeader {
+		t.Fatalf("Should fail when header can not be parsed")
+	}
+
+	if _, err := ParseServerHeader("(bad header)"); err != errInvalidHeader {
+		t.Fatalf("Should fail when header can not be parsed")
+	}
+
+	if _, err := ParseServerHeader("(without/spaces)"); err != errInvalidHeader {
+		t.Fatalf("Should fail when header can not be parsed")
+	}
+
+	if _, err := ParseServerHeader("(header/with space)"); err != errInvalidHeader {
+		t.Fatalf("Expected err to not exist when ParseServerHeader(\"(header/with space)\")")
+	}
+
+	serverHeader, err := ParseServerHeader("foo/bar (baz)")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if serverHeader.App != "foo" {
+		t.Fatalf("Expected serverHeader.App to equal \"foo\", got %s", serverHeader.App)
+	}
+
+	if serverHeader.Ver != "bar" {
+		t.Fatalf("Expected serverHeader.Ver to equal \"bar\", got %s", serverHeader.Ver)
+	}
+
+	if serverHeader.OS != "baz" {
+		t.Fatalf("Expected serverHeader.OS to equal \"baz\", got %s", serverHeader.OS)
+	}
+}
diff --git a/pkg/httputils/mimetype_test.go b/pkg/httputils/mimetype_test.go
new file mode 100644
index 0000000000..9de433ee8c
--- /dev/null
+++ b/pkg/httputils/mimetype_test.go
@@ -0,0 +1,13 @@
+package httputils
+
+import (
+	"testing"
+)
+
+func TestDetectContentType(t *testing.T) {
+	input := []byte("That is just a plain text")
+
+	if contentType, _, err := DetectContentType(input); err != nil || contentType != "text/plain" {
+		t.Errorf("TestDetectContentType failed")
+	}
+}