Decodes input and encodes output

Currently novaclient doesn't handle properly incoming and outgoing
encode / decode process. As a solution for this, this patch implements a
decoding process for all data incoming from the user side and decodes
everything going out of the client, i.e: http requests, prints, etc.

This patch introduces a new module (strutils.py) taken from
oslo-incubator in order to use 2 of the functions present in it:

About safe_(decode|encode):

    Both functions try to encode / decode the incoming text using the
    stdin encoding, fallback to python's default encoding if that
    returns None or to UTF-8 as the last option.

    In both functions only basestring objects are accepted and they both
    raise TypeError if an object of another type is passed.

About the general novaclient changes:

    In order to better support non-ASCII characters, it is a good
    practice to use unicode interanlly and encode everything that has to
    go out. This patch aims to do that and introduces this behaviour in
    the client.

Testing:

    A good test (besides using tox) is to use nova client with and
    without setting any locale (export LANG=).

Fixes bug: 1061156

Change-Id: I20b75e42b0c3dac89f1048faa1127253a64f86c7

novaclient/openstack/common/strutils.py

@@ -0,0 +1,133 @@
+# vim: tabstop=4 shiftwidth=4 softtabstop=4
+
+# Copyright 2011 OpenStack LLC.
+# All Rights Reserved.
+#
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+"""
+System-level utilities and helper functions.
+"""
+
+import logging
+import sys
+
+LOG = logging.getLogger(__name__)
+
+
+def int_from_bool_as_string(subject):
+    """
+    Interpret a string as a boolean and return either 1 or 0.
+
+    Any string value in:
+
+        ('True', 'true', 'On', 'on', '1')
+
+    is interpreted as a boolean True.
+
+    Useful for JSON-decoded stuff and config file parsing
+    """
+    return bool_from_string(subject) and 1 or 0
+
+
+def bool_from_string(subject):
+    """
+    Interpret a string as a boolean.
+
+    Any string value in:
+
+        ('True', 'true', 'On', 'on', 'Yes', 'yes', '1')
+
+    is interpreted as a boolean True.
+
+    Useful for JSON-decoded stuff and config file parsing
+    """
+    if isinstance(subject, bool):
+        return subject
+    if isinstance(subject, basestring):
+        if subject.strip().lower() in ('true', 'on', 'yes', '1'):
+            return True
+    return False
+
+
+def safe_decode(text, incoming=None, errors='strict'):
+    """
+    Decodes incoming str using `incoming` if they're
+    not already unicode.
+
+    :param incoming: Text's current encoding
+    :param errors: Errors handling policy. See here for valid
+        values http://docs.python.org/2/library/codecs.html
+    :returns: text or a unicode `incoming` encoded
+                representation of it.
+    :raises TypeError: If text is not an isntance of basestring
+    """
+    if not isinstance(text, basestring):
+        raise TypeError("%s can't be decoded" % type(text))
+
+    if isinstance(text, unicode):
+        return text
+
+    if not incoming:
+        incoming = (sys.stdin.encoding or
+                    sys.getdefaultencoding())
+
+    try:
+        return text.decode(incoming, errors)
+    except UnicodeDecodeError:
+        # Note(flaper87) If we get here, it means that
+        # sys.stdin.encoding / sys.getdefaultencoding
+        # didn't return a suitable encoding to decode
+        # text. This happens mostly when global LANG
+        # var is not set correctly and there's no
+        # default encoding. In this case, most likely
+        # python will use ASCII or ANSI encoders as
+        # default encodings but they won't be capable
+        # of decoding non-ASCII characters.
+        #
+        # Also, UTF-8 is being used since it's an ASCII
+        # extension.
+        return text.decode('utf-8', errors)
+
+
+def safe_encode(text, incoming=None,
+                encoding='utf-8', errors='strict'):
+    """
+    Encodes incoming str/unicode using `encoding`. If
+    incoming is not specified, text is expected to
+    be encoded with current python's default encoding.
+    (`sys.getdefaultencoding`)
+
+    :param incoming: Text's current encoding
+    :param encoding: Expected encoding for text (Default UTF-8)
+    :param errors: Errors handling policy. See here for valid
+        values http://docs.python.org/2/library/codecs.html
+    :returns: text or a bytestring `encoding` encoded
+                representation of it.
+    :raises TypeError: If text is not an isntance of basestring
+    """
+    if not isinstance(text, basestring):
+        raise TypeError("%s can't be encoded" % type(text))
+
+    if not incoming:
+        incoming = (sys.stdin.encoding or
+                    sys.getdefaultencoding())
+
+    if isinstance(text, unicode):
+        return text.encode(encoding, errors)
+    elif text and encoding != incoming:
+        # Decode text before encoding it with `encoding`
+        text = safe_decode(text, incoming, errors)
+        return text.encode(encoding, errors)
+
+    return text

novaclient/shell.py

@@ -49,6 +49,7 @@ import novaclient
 from novaclient import client
 from novaclient import exceptions as exc
 import novaclient.extension
+from novaclient.openstack.common import strutils
 from novaclient import utils
 from novaclient.v1_1 import shell as shell_v1_1
 
@@ -738,11 +739,11 @@ class OpenStackHelpFormatter(argparse.HelpFormatter):
 
 def main():
     try:
-        OpenStackComputeShell().main(sys.argv[1:])
+        OpenStackComputeShell().main(map(strutils.safe_decode, sys.argv[1:]))
 
     except Exception as e:
         logger.debug(e, exc_info=1)
-        print("ERROR: %s" % unicode(e), file=sys.stderr)
+        print("ERROR: %s" % strutils.safe_encode(unicode(e)), file=sys.stderr)
         sys.exit(1)
 
 

novaclient/utils.py

@@ -6,6 +6,7 @@ import uuid
 import prettytable
 
 from novaclient import exceptions
+from novaclient.openstack.common import strutils
 
 
 def arg(*args, **kwargs):
@@ -139,7 +140,7 @@ def pretty_choice_list(l):
 
 
 def print_list(objs, fields, formatters={}, sortby_index=0):
-    if sortby_index == None:
+    if sortby_index is None:
         sortby = None
     else:
         sortby = fields[sortby_index]
@@ -162,9 +163,9 @@ def print_list(objs, fields, formatters={}, sortby_index=0):
         pt.add_row(row)
 
     if sortby is not None:
-        print(pt.get_string(sortby=sortby))
+        print(strutils.safe_encode(pt.get_string(sortby=sortby)))
     else:
-        print(pt.get_string())
+        print(strutils.safe_encode(pt.get_string()))
 
 
 def print_dict(d, dict_property="Property"):
@@ -184,7 +185,7 @@ def print_dict(d, dict_property="Property"):
                 col1 = ''
         else:
             pt.add_row([k, v])
-    print(pt.get_string())
+    print(strutils.safe_encode(pt.get_string()))
 
 
 def find_resource(manager, name_or_id):
@@ -203,9 +204,9 @@ def find_resource(manager, name_or_id):
 
     # now try to get entity as uuid
     try:
-        uuid.UUID(str(name_or_id))
+        uuid.UUID(strutils.safe_encode(name_or_id))
         return manager.get(name_or_id)
-    except (ValueError, exceptions.NotFound):
+    except (TypeError, ValueError, exceptions.NotFound):
         pass
 
     # for str id which is not uuid (for Flavor search currently)

novaclient/v1_1/base.py

@@ -18,6 +18,7 @@
 import base64
 
 from novaclient import base
+from novaclient.openstack.common import strutils
 
 
 # FIXME(sirp): Now that v1_0 has been removed, this can be merged with
@@ -72,8 +73,8 @@ class BootingManagerWithFind(base.ManagerWithFind):
         if userdata:
             if hasattr(userdata, 'read'):
                 userdata = userdata.read()
-            elif isinstance(userdata, unicode):
-                userdata = userdata.encode('utf-8')
+
+            userdata = strutils.safe_encode(userdata)
             body["server"]["user_data"] = base64.b64encode(userdata)
         if meta:
             body["server"]["metadata"] = meta

openstack-common.conf

@@ -1,7 +1,7 @@
 [DEFAULT]
 
 # The list of modules to copy from openstack-common
-modules=setup,timeutils
+modules=setup,timeutils,strutils
 
 # The base module to hold the copy of openstack.common
 base=novaclient