Support for version and extension discoveryessex-3

- Supports unauthenticated call to Keystone to discover
  supported API versions
- Added command-line support (usage: keystone discover)
- Added client support (keystoneclient.genenric client).
  Client returns dicts, whereas shell command prints
  formated output.
- Added tests for genenric client
- Replicates 'nove discover' in python-novaclient
- Starts to address blueprint keystone-client
- keystone discover output looks like this:
    $ keystone discover
    Keystone found at http://localhost:35357
        - supports version v1.0 (DEPRECATED) here http://localhost:35357/v1.0
        - supports version v1.1 (CURRENT) here http://localhost:35357/v1.1
        - supports version v2.0 (BETA) here http://localhost:35357/v2.0
            - and HP-IDM: HP Token Validation Extension
            - and OS-KSADM: Openstack Keystone Admin
            - and OS-KSCATALOG: Openstack Keystone Catalog

Change-Id: Id16d34dac094c780d36afb3e31c98c318b6071ac

1 files changed, 27 insertions, 20 deletions

diff --git a/keystoneclient/shell.py b/keystoneclient/shell.py
index 01f7fc5..ba30054 100644
--- a/keystoneclient/shell.py
+++ b/keystoneclient/shell.py
@@ -26,6 +26,7 @@ import sys
 from keystoneclient import exceptions as exc
 from keystoneclient import utils
 from keystoneclient.v2_0 import shell as shell_v2_0
+from keystoneclient.generic import shell as shell_generic
 
 
 def env(e):
@@ -99,6 +100,7 @@ class OpenStackIdentityShell(object):
             actions_module = shell_v2_0
 
         self._find_actions(subparsers, actions_module)
+        self._find_actions(subparsers, shell_generic)
         self._find_actions(subparsers, self)
 
         return parser
@@ -151,28 +153,33 @@ class OpenStackIdentityShell(object):
         #FIXME(usrleon): Here should be restrict for project id same as
         # for username or apikey but for compatibility it is not.
 
-        if not args.os_username:
-            raise exc.CommandError("You must provide a username:"
-                                   "via --username or env[OS_USERNAME]")
-        if not args.os_password:
-            raise exc.CommandError("You must provide a password, either"
-                                   "via --password or env[OS_PASSWORD]")
-
-        if not args.os_auth_url:
-            raise exc.CommandError("You must provide a auth url, either"
-                                   "via --os-auth_url or via"
-                                    "env[OS_AUTH_URL]")
-
-        self.cs = self.get_api_class(options.os_version)(
-                                     username=args.os_username,
-                                     tenant_name=args.os_tenant_name,
-                                     tenant_id=args.os_tenant_id,
-                                     password=args.os_password,
-                                     auth_url=args.os_auth_url,
-                                     region_name=args.os_region_name)
+        if not utils.isunauthenticated(args.func):
+            if not args.os_username:
+                raise exc.CommandError("You must provide a username:"
+                                       "via --username or env[OS_USERNAME]")
+            if not args.os_password:
+                raise exc.CommandError("You must provide a password, either"
+                                       "via --password or env[OS_PASSWORD]")
+
+            if not args.os_auth_url:
+                raise exc.CommandError("You must provide a auth url, either"
+                                       "via --os-auth_url or via"
+                                        "env[OS_AUTH_URL]")
+
+        if utils.isunauthenticated(args.func):
+            self.cs = shell_generic.CLIENT_CLASS(endpoint=args.os_auth_url)
+        else:
+            self.cs = self.get_api_class(options.version)(
+                username=args.os_username,
+                tenant_name=args.os_tenant_name,
+                tenant_id=args.os_tenant_id,
+                password=args.os_password,
+                auth_url=args.os_auth_url,
+                region_name=args.os_region_name)
 
         try:
-            self.cs.authenticate()
+            if not utils.isunauthenticated(args.func):
+                self.cs.authenticate()
         except exc.Unauthorized:
             raise exc.CommandError("Invalid OpenStack Keystone credentials.")
         except exc.AuthorizationFailure: