if we can't connect to the server when setting up, return a nil roundtripper. Check roundtripper when initializing HTTPStore and substitute an OfflineStore if it is nil.

Signed-off-by: David Lawrence <david.lawrence@docker.com> (github: endophage)

cmd/notary/tuf.go

@@ -426,7 +426,9 @@ func tokenAuth(config *viper.Viper, baseTransport *http.Transport, gun string,
 	}
 	resp, err := pingClient.Do(req)
 	if err != nil {
-		fatalf(err.Error())
+		logrus.Errorf("could not reach %s: %s", trustServerURL, err.Error())
+		logrus.Info("continuing in offline mode")
+		return nil
 	}
 	defer resp.Body.Close()
 

tuf/store/httpstore.go

@@ -85,6 +85,9 @@ func NewHTTPStore(baseURL, metaPrefix, metaExtension, targetsPrefix, keyExtensio
 	if !base.IsAbs() {
 		return nil, errors.New("HTTPStore requires an absolute baseURL")
 	}
+	if roundTrip == nil {
+		return &OfflineStore{}, nil
+	}
 	return &HTTPStore{
 		baseURL:       *base,
 		metaPrefix:    metaPrefix,