Merge "Import strutils from oslo" into stable/havana

2 files changed, 219 insertions, 0 deletions

diff --git a/keystone/openstack/common/strutils.py b/keystone/openstack/common/strutils.py
new file mode 100644
index 000000000..3a1067ef9
--- /dev/null
+++ b/keystone/openstack/common/strutils.py
@@ -0,0 +1,218 @@
+# vim: tabstop=4 shiftwidth=4 softtabstop=4
+
+# Copyright 2011 OpenStack Foundation.
+# 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 re
+import sys
+import unicodedata
+
+import six
+
+from keystone.openstack.common.gettextutils import _  # noqa
+
+
+# Used for looking up extensions of text
+# to their 'multiplied' byte amount
+BYTE_MULTIPLIERS = {
+    '': 1,
+    't': 1024 ** 4,
+    'g': 1024 ** 3,
+    'm': 1024 ** 2,
+    'k': 1024,
+}
+BYTE_REGEX = re.compile(r'(^-?\d+)(\D*)')
+
+TRUE_STRINGS = ('1', 't', 'true', 'on', 'y', 'yes')
+FALSE_STRINGS = ('0', 'f', 'false', 'off', 'n', 'no')
+
+SLUGIFY_STRIP_RE = re.compile(r"[^\w\s-]")
+SLUGIFY_HYPHENATE_RE = re.compile(r"[-\s]+")
+
+
+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, strict=False):
+    """Interpret a string as a boolean.
+
+    A case-insensitive match is performed such that strings matching 't',
+    'true', 'on', 'y', 'yes', or '1' are considered True and, when
+    `strict=False`, anything else is considered False.
+
+    Useful for JSON-decoded stuff and config file parsing.
+
+    If `strict=True`, unrecognized values, including None, will raise a
+    ValueError which is useful when parsing values passed in from an API call.
+    Strings yielding False are 'f', 'false', 'off', 'n', 'no', or '0'.
+    """
+    if not isinstance(subject, six.string_types):
+        subject = str(subject)
+
+    lowered = subject.strip().lower()
+
+    if lowered in TRUE_STRINGS:
+        return True
+    elif lowered in FALSE_STRINGS:
+        return False
+    elif strict:
+        acceptable = ', '.join(
+            "'%s'" % s for s in sorted(TRUE_STRINGS + FALSE_STRINGS))
+        msg = _("Unrecognized value '%(val)s', acceptable values are:"
+                " %(acceptable)s") % {'val': subject,
+                                      'acceptable': acceptable}
+        raise ValueError(msg)
+    else:
+        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 str
+    """
+    if not isinstance(text, six.string_types):
+        raise TypeError("%s can't be decoded" % type(text))
+
+    if isinstance(text, six.text_type):
+        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 str
+    """
+    if not isinstance(text, six.string_types):
+        raise TypeError("%s can't be encoded" % type(text))
+
+    if not incoming:
+        incoming = (sys.stdin.encoding or
+                    sys.getdefaultencoding())
+
+    if isinstance(text, six.text_type):
+        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
+
+
+def to_bytes(text, default=0):
+    """Converts a string into an integer of bytes.
+
+    Looks at the last characters of the text to determine
+    what conversion is needed to turn the input text into a byte number.
+    Supports "B, K(B), M(B), G(B), and T(B)". (case insensitive)
+
+    :param text: String input for bytes size conversion.
+    :param default: Default return value when text is blank.
+
+    """
+    match = BYTE_REGEX.search(text)
+    if match:
+        magnitude = int(match.group(1))
+        mult_key_org = match.group(2)
+        if not mult_key_org:
+            return magnitude
+    elif text:
+        msg = _('Invalid string format: %s') % text
+        raise TypeError(msg)
+    else:
+        return default
+    mult_key = mult_key_org.lower().replace('b', '', 1)
+    multiplier = BYTE_MULTIPLIERS.get(mult_key)
+    if multiplier is None:
+        msg = _('Unknown byte multiplier: %s') % mult_key_org
+        raise TypeError(msg)
+    return magnitude * multiplier
+
+
+def to_slug(value, incoming=None, errors="strict"):
+    """Normalize string.
+
+    Convert to lowercase, remove non-word characters, and convert spaces
+    to hyphens.
+
+    Inspired by Django's `slugify` filter.
+
+    :param value: Text to slugify
+    :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: slugified unicode representation of `value`
+    :raises TypeError: If text is not an instance of str
+    """
+    value = safe_decode(value, incoming, errors)
+    # NOTE(aababilov): no need to use safe_(encode|decode) here:
+    # encodings are always "ascii", error handling is always "ignore"
+    # and types are always known (first: unicode; second: str)
+    value = unicodedata.normalize("NFKD", value).encode(
+        "ascii", "ignore").decode("ascii")
+    value = SLUGIFY_STRIP_RE.sub("", value).strip().lower()
+    return SLUGIFY_HYPHENATE_RE.sub("-", value)
diff --git a/openstack-common.conf b/openstack-common.conf
index e36745c7b..a282cadd6 100644
--- a/openstack-common.conf
+++ b/openstack-common.conf
@@ -10,6 +10,7 @@ module=jsonutils
 module=patch_tox_venv
 module=policy
 module=redhat-eventlet.patch
+module=strutils
 module=timeutils
 
 # The base module to hold the copy of openstack.common