python-glanceclient/glanceclient/common/utils.py

454 lines
14 KiB
Python

# Copyright 2012 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.
from __future__ import print_function
import errno
import hashlib
import json
import os
import re
import sys
import threading
import uuid
from oslo_utils import importutils
import six
if os.name == 'nt':
import msvcrt
else:
msvcrt = None
from oslo_utils import encodeutils
from oslo_utils import strutils
import prettytable
from glanceclient import exc
_memoized_property_lock = threading.Lock()
SENSITIVE_HEADERS = ('X-Auth-Token', )
# Decorator for cli-args
def arg(*args, **kwargs):
def _decorator(func):
# Because of the sematics of decorator composition if we just append
# to the options list positional options will appear to be backwards.
func.__dict__.setdefault('arguments', []).insert(0, (args, kwargs))
return func
return _decorator
def schema_args(schema_getter, omit=None):
omit = omit or []
typemap = {
'string': str,
'integer': int,
'boolean': strutils.bool_from_string,
'array': list
}
def _decorator(func):
schema = schema_getter()
if schema is None:
param = '<unavailable>'
kwargs = {
'help': ("Please run with connection parameters set to "
"retrieve the schema for generating help for this "
"command")
}
func.__dict__.setdefault('arguments', []).insert(0, ((param, ),
kwargs))
else:
properties = schema.get('properties', {})
for name, property in six.iteritems(properties):
if name in omit:
continue
param = '--' + name.replace('_', '-')
kwargs = {}
type_str = property.get('type', 'string')
if isinstance(type_str, list):
# NOTE(flaper87): This means the server has
# returned something like `['null', 'string']`,
# therfore we use the first non-`null` type as
# the valid type.
for t in type_str:
if t != 'null':
type_str = t
break
if type_str == 'array':
items = property.get('items')
kwargs['type'] = typemap.get(items.get('type'))
kwargs['nargs'] = '+'
else:
kwargs['type'] = typemap.get(type_str)
if type_str == 'boolean':
kwargs['metavar'] = '[True|False]'
else:
kwargs['metavar'] = '<%s>' % name.upper()
description = property.get('description', "")
if 'enum' in property:
if len(description):
description += " "
# NOTE(flaper87): Make sure all values are `str/unicode`
# for the `join` to succeed. Enum types can also be `None`
# therfore, join's call would fail without the following
# list comprehension
vals = [six.text_type(val) for val in property.get('enum')]
description += ('Valid values: ' + ', '.join(vals))
kwargs['help'] = description
func.__dict__.setdefault('arguments',
[]).insert(0, ((param, ), kwargs))
return func
return _decorator
def pretty_choice_list(l):
return ', '.join("'%s'" % i for i in l)
def print_list(objs, fields, formatters=None, field_settings=None):
formatters = formatters or {}
field_settings = field_settings or {}
pt = prettytable.PrettyTable([f for f in fields], caching=False)
pt.align = 'l'
for o in objs:
row = []
for field in fields:
if field in field_settings:
for setting, value in six.iteritems(field_settings[field]):
setting_dict = getattr(pt, setting)
setting_dict[field] = value
if field in formatters:
row.append(formatters[field](o))
else:
field_name = field.lower().replace(' ', '_')
data = getattr(o, field_name, None) or ''
row.append(data)
pt.add_row(row)
print(encodeutils.safe_decode(pt.get_string()))
def print_dict(d, max_column_width=80):
pt = prettytable.PrettyTable(['Property', 'Value'], caching=False)
pt.align = 'l'
pt.max_width = max_column_width
for k, v in six.iteritems(d):
if isinstance(v, (dict, list)):
v = json.dumps(v)
pt.add_row([k, v])
print(encodeutils.safe_decode(pt.get_string(sortby='Property')))
def find_resource(manager, name_or_id):
"""Helper for the _find_* methods."""
# first try to get entity as integer id
try:
if isinstance(name_or_id, int) or name_or_id.isdigit():
return manager.get(int(name_or_id))
except exc.NotFound:
pass
# now try to get entity as uuid
try:
# This must be unicode for Python 3 compatibility.
# If you pass a bytestring to uuid.UUID, you will get a TypeError
uuid.UUID(encodeutils.safe_decode(name_or_id))
return manager.get(name_or_id)
except (ValueError, exc.NotFound):
pass
# finally try to find entity by name
matches = list(manager.list(filters={'name': name_or_id}))
num_matches = len(matches)
if num_matches == 0:
msg = "No %s with a name or ID of '%s' exists." % \
(manager.resource_class.__name__.lower(), name_or_id)
raise exc.CommandError(msg)
elif num_matches > 1:
msg = ("Multiple %s matches found for '%s', use an ID to be more"
" specific." % (manager.resource_class.__name__.lower(),
name_or_id))
raise exc.CommandError(msg)
else:
return matches[0]
def skip_authentication(f):
"""Function decorator used to indicate a caller may be unauthenticated."""
f.require_authentication = False
return f
def is_authentication_required(f):
"""Checks to see if the function requires authentication.
Use the skip_authentication decorator to indicate a caller may
skip the authentication step.
"""
return getattr(f, 'require_authentication', True)
def env(*vars, **kwargs):
"""Search for the first defined of possibly many env vars.
Returns the first environment variable defined in vars, or
returns the default defined in kwargs.
"""
for v in vars:
value = os.environ.get(v, None)
if value:
return value
return kwargs.get('default', '')
def import_versioned_module(version, submodule=None):
module = 'glanceclient.v%s' % version
if submodule:
module = '.'.join((module, submodule))
return importutils.import_module(module)
def exit(msg='', exit_code=1):
if msg:
print(encodeutils.safe_decode(msg), file=sys.stderr)
sys.exit(exit_code)
def save_image(data, path):
"""Save an image to the specified path.
:param data: binary data of the image
:param path: path to save the image to
"""
if path is None:
image = sys.stdout
else:
image = open(path, 'wb')
try:
for chunk in data:
image.write(chunk)
finally:
if path is not None:
image.close()
def make_size_human_readable(size):
suffix = ['B', 'kB', 'MB', 'GB', 'TB', 'PB', 'EB', 'ZB']
base = 1024.0
index = 0
while size >= base:
index = index + 1
size = size / base
padded = '%.1f' % size
stripped = padded.rstrip('0').rstrip('.')
return '%s%s' % (stripped, suffix[index])
def getsockopt(self, *args, **kwargs):
"""
A function which allows us to monkey patch eventlet's
GreenSocket, adding a required 'getsockopt' method.
TODO: (mclaren) we can remove this once the eventlet fix
(https://bitbucket.org/eventlet/eventlet/commits/609f230)
lands in mainstream packages.
"""
return self.fd.getsockopt(*args, **kwargs)
def exception_to_str(exc):
try:
error = six.text_type(exc)
except UnicodeError:
try:
error = str(exc)
except UnicodeError:
error = ("Caught '%(exception)s' exception." %
{"exception": exc.__class__.__name__})
return encodeutils.safe_decode(error, errors='ignore')
def get_file_size(file_obj):
"""Analyze file-like object and attempt to determine its size.
:param file_obj: file-like object.
:retval The file's size or None if it cannot be determined.
"""
if (hasattr(file_obj, 'seek') and hasattr(file_obj, 'tell') and
(six.PY2 or six.PY3 and file_obj.seekable())):
try:
curr = file_obj.tell()
file_obj.seek(0, os.SEEK_END)
size = file_obj.tell()
file_obj.seek(curr)
return size
except IOError as e:
if e.errno == errno.ESPIPE:
# Illegal seek. This means the file object
# is a pipe (e.g. the user is trying
# to pipe image data to the client,
# echo testdata | bin/glance add blah...), or
# that file object is empty, or that a file-like
# object which doesn't support 'seek/tell' has
# been supplied.
return
else:
raise
def get_data_file(args):
if args.file:
return open(args.file, 'rb')
else:
# distinguish cases where:
# (1) stdin is not valid (as in cron jobs):
# glance ... <&-
# (2) image data is provided through standard input:
# glance ... < /tmp/file or cat /tmp/file | glance ...
# (3) no image data provided:
# glance ...
try:
os.fstat(0)
except OSError:
# (1) stdin is not valid (closed...)
return None
if not sys.stdin.isatty():
# (2) image data is provided through standard input
if msvcrt:
msvcrt.setmode(sys.stdin.fileno(), os.O_BINARY)
return sys.stdin
else:
# (3) no image data provided
return None
def strip_version(endpoint):
"""Strip version from the last component of endpoint if present."""
# NOTE(flaper87): This shouldn't be necessary if
# we make endpoint the first argument. However, we
# can't do that just yet because we need to keep
# backwards compatibility.
if not isinstance(endpoint, six.string_types):
raise ValueError("Expected endpoint")
version = None
# Get rid of trailing '/' if present
endpoint = endpoint.rstrip('/')
url_bits = endpoint.split('/')
# regex to match 'v1' or 'v2.0' etc
if re.match('v\d+\.?\d*', url_bits[-1]):
version = float(url_bits[-1].lstrip('v'))
endpoint = '/'.join(url_bits[:-1])
return endpoint, version
def print_image(image_obj, human_readable=False, max_col_width=None):
ignore = ['self', 'access', 'file', 'schema']
image = dict([item for item in six.iteritems(image_obj)
if item[0] not in ignore])
if human_readable:
image['size'] = make_size_human_readable(image['size'])
if str(max_col_width).isdigit():
print_dict(image, max_column_width=max_col_width)
else:
print_dict(image)
def integrity_iter(iter, checksum):
"""Check image data integrity.
:raises: IOError
"""
md5sum = hashlib.md5()
for chunk in iter:
yield chunk
if isinstance(chunk, six.string_types):
chunk = six.b(chunk)
md5sum.update(chunk)
md5sum = md5sum.hexdigest()
if md5sum != checksum:
raise IOError(errno.EPIPE,
'Corrupt image download. Checksum was %s expected %s' %
(md5sum, checksum))
def memoized_property(fn):
attr_name = '_lazy_once_' + fn.__name__
@property
def _memoized_property(self):
if hasattr(self, attr_name):
return getattr(self, attr_name)
else:
with _memoized_property_lock:
if not hasattr(self, attr_name):
setattr(self, attr_name, fn(self))
return getattr(self, attr_name)
return _memoized_property
def safe_header(name, value):
if name in SENSITIVE_HEADERS:
v = value.encode('utf-8')
h = hashlib.sha1(v)
d = h.hexdigest()
return name, "{SHA1}%s" % d
else:
return name, value
def endpoint_version_from_url(endpoint, default_version=None):
if endpoint:
endpoint, version = strip_version(endpoint)
return endpoint, version or default_version
else:
return None, default_version
class IterableWithLength(object):
def __init__(self, iterable, length):
self.iterable = iterable
self.length = length
def __iter__(self):
try:
for chunk in self.iterable:
yield chunk
finally:
self.iterable.close()
def next(self):
return next(self.iterable)
def __len__(self):
return self.length