From dcf081d758a5a090d6fac3d2d2cf3022d86738fd Mon Sep 17 00:00:00 2001
From: Ben Firshman <ben@firshman.co.uk>
Date: Sat, 6 Dec 2014 20:54:15 +0100
Subject: [PATCH] Check that public key exists when creating machine

Fixes #4

Signed-off-by: Ben Firshman <ben@firshman.co.uk>
---
 commands.go      |  8 ++++++++
 drivers/utils.go | 16 +++++++++++++++-
 2 files changed, 23 insertions(+), 1 deletion(-)

diff --git a/commands.go b/commands.go
index ed2069ade9..7c6c06f094 100644
--- a/commands.go
+++ b/commands.go
@@ -180,6 +180,14 @@ func (cli *DockerCli) CmdCreate(args ...string) error {
 		return nil
 	}
 
+	keyExists, err := drivers.PublicKeyExists()
+	if err != nil {
+		return err
+	}
+	if !keyExists {
+		log.Fatalf("Identity auth public key does not exist at %s. Please run the docker client without any options to create it.", drivers.PublicKeyPath())
+	}
+
 	name := cmd.Arg(0)
 
 	store := NewStore()
diff --git a/drivers/utils.go b/drivers/utils.go
index 0fa57f10c8..b8bbeca44f 100644
--- a/drivers/utils.go
+++ b/drivers/utils.go
@@ -6,8 +6,12 @@ import (
 	"path/filepath"
 )
 
+func PublicKeyPath() string {
+	return filepath.Join(os.Getenv("HOME"), ".docker/public-key.json")
+}
+
 func AddPublicKeyToAuthorizedHosts(d Driver, authorizedKeysPath string) error {
-	f, err := os.Open(filepath.Join(os.Getenv("HOME"), ".docker/public-key.json"))
+	f, err := os.Open(PublicKeyPath())
 	if err != nil {
 		return err
 	}
@@ -21,3 +25,13 @@ func AddPublicKeyToAuthorizedHosts(d Driver, authorizedKeysPath string) error {
 	cmd.Stdin = f
 	return cmd.Run()
 }
+
+func PublicKeyExists() (bool, error) {
+	_, err := os.Stat(PublicKeyPath())
+	if err == nil {
+		return true, nil
+	} else if os.IsNotExist(err) {
+		return false, nil
+	}
+	return false, err
+}