Provide upgrade choices for stable and testing

README.rst

@@ -49,6 +49,11 @@ using the following command-line::
 
     vagga _box upgrade_vagga
 
+By default the command above will upgrade to the latest stable vagga version. If
+you want to upgrade to the latest testing version of vagga pass
+:code:`--testing` argument to the command::
+
+    vagga _box upgrade_vagga --testing
 
 Short FAQ
 =========

image/http/upgrade-vagga.sh

@@ -1,2 +1,17 @@
 #!/bin/sh
-curl -sfS http://files.zerogw.com/vagga/vagga-install-testing.sh | sh
+
+case "$1" in
+    # If no arguments provided update to the latest stable version
+    ''|--stable)
+        install_script="vagga-install.sh"
+        ;;
+    --testing)
+        install_script="vagga-install-testing.sh"
+        ;;
+    *)
+        echo 'Specify one of "--stable", "--testing"' >&2
+        exit 1
+        ;;
+esac
+
+curl -sfS "http://files.zerogw.com/vagga/${install_script}" | sh

vagga_box/main.py

@@ -110,8 +110,10 @@ def main():
             virtualbox.stop_vm()
             return sys.exit(0)
         elif args.command[1:2] == ['upgrade_vagga']:
+            upgrade_mode = args.command[2:3]
+            upgarde_cmd = ['/usr/local/bin/upgrade-vagga'] + upgrade_mode
             returncode = subprocess.Popen(
-                    BASE_SSH_COMMAND + ['/usr/local/bin/upgrade-vagga'],
+                    BASE_SSH_COMMAND + upgarde_cmd
                 ).wait()
             return sys.exit(returncode)
         elif args.command[1:2] == ['mount']: