Add "start_version" and "end_version" support to argparse

Now, "cinder help subcommand" can not show whether an argument
is supported for a specific microversion.
With this change, developers only need to add a start_version or
end_version in the utils.arg wrap, cinderclient will support
the microversion for that arguement.

    @utils.arg(
    '--foo',
    start_version='3.1')
    @utils.arg(
    '--bar',
    start_version='3.2',
    end_version='3.5')
    def do_some_action():
        ......

In previous example, an exception will be raised for such command:
   $ cinder --os-volume-api-version 3.6 --bar some-ation

And only "--foo" will show up for such help command:
   $ cinder --os-volume-api-version 3.1 help some-ation

Change-Id: I74137486992846bbf9fdff53c009851db2356eef
Partial-Bug: #1600567
Co-Authored-By: Nate Potter <nathaniel.potter@intel.com>

1 files changed, 28 insertions, 0 deletions

diff --git a/cinderclient/exceptions.py b/cinderclient/exceptions.py
index 72366c3..6d9e707 100644
--- a/cinderclient/exceptions.py
+++ b/cinderclient/exceptions.py
@@ -28,6 +28,34 @@ class UnsupportedVersion(Exception):
     pass
 
 
+class UnsupportedAttribute(AttributeError):
+    """Indicates that the user is trying to transmit the argument to a method,
+    which is not supported by selected version.
+    """
+
+    def __init__(self, argument_name, start_version, end_version):
+        if not start_version.is_null() and not end_version.is_null():
+            self.message = (
+                "'%(name)s' argument is only allowed for microversions "
+                "%(start)s - %(end)s." % {"name": argument_name,
+                                          "start": start_version.get_string(),
+                                          "end": end_version.get_string()})
+        elif not start_version.is_null():
+            self.message = (
+                "'%(name)s' argument is only allowed since microversion "
+                "%(start)s." % {"name": argument_name,
+                                "start": start_version.get_string()})
+
+        elif not end_version.is_null():
+            self.message = (
+                "'%(name)s' argument is not allowed after microversion "
+                "%(end)s." % {"name": argument_name,
+                              "end": end_version.get_string()})
+
+    def __str__(self):
+        return self.message
+
+
 class InvalidAPIVersion(Exception):
     pass