# Licensed to the Apache Software Foundation (ASF) under one or more
# contributor license agreements. See the NOTICE file distributed with
# this work for additional information regarding copyright ownership.
# The ASF licenses this file to You 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.
import os
import sys
import binascii
__all__ = [
'get_driver',
'set_driver',
'merge_valid_keys',
'get_new_obj',
'str2dicts',
'dict2str',
'reverse_dict',
'lowercase_keys',
'get_secure_random_string'
]
[docs]def get_driver(drivers, provider):
"""
Get a driver.
:param drivers: Dictionary containing valid providers.
:param provider: Id of provider to get driver
:type provider: :class:`libcloud.types.Provider`
"""
if provider in drivers:
mod_name, driver_name = drivers[provider]
_mod = __import__(mod_name, globals(), locals(), [driver_name])
return getattr(_mod, driver_name)
raise AttributeError('Provider %s does not exist' % (provider))
[docs]def set_driver(drivers, provider, module, klass):
"""
Sets a driver.
:param drivers: Dictionary to store providers.
:param provider: Id of provider to set driver for
:type provider: :class:`libcloud.types.Provider`
:param module: The module which contains the driver
:type module: L
:param klass: The driver class name
:type klass:
"""
if provider in drivers:
raise AttributeError('Provider %s already registered' % (provider))
drivers[provider] = (module, klass)
# Check if this driver is valid
try:
driver = get_driver(drivers, provider)
except (ImportError, AttributeError):
exp = sys.exc_info()[1]
drivers.pop(provider)
raise exp
return driver
[docs]def merge_valid_keys(params, valid_keys, extra):
"""
Merge valid keys from extra into params dictionary and return
dictionary with keys which have been merged.
Note: params is modified in place.
"""
merged = {}
if not extra:
return merged
for key in valid_keys:
if key in extra:
params[key] = extra[key]
merged[key] = extra[key]
return merged
[docs]def get_new_obj(obj, klass, attributes):
"""
Pass attributes from the existing object 'obj' and attributes
dictionary to a 'klass' constructor.
Attributes from 'attributes' dictionary are only passed to the
constructor if they are not None.
"""
kwargs = {}
for key, value in list(obj.__dict__.items()):
if isinstance(value, dict):
kwargs[key] = value.copy()
elif isinstance(value, (tuple, list)):
kwargs[key] = value[:]
else:
kwargs[key] = value
for key, value in list(attributes.items()):
if value is None:
continue
if isinstance(value, dict):
kwargs_value = kwargs.get(key, {})
for key1, value2 in list(value.items()):
if value2 is None:
continue
kwargs_value[key1] = value2
kwargs[key] = kwargs_value
else:
kwargs[key] = value
return klass(**kwargs)
[docs]def str2dicts(data):
"""
Create a list of dictionaries from a whitespace and newline delimited text.
For example, this:
cpu 1100
ram 640
cpu 2200
ram 1024
becomes:
[{'cpu': '1100', 'ram': '640'}, {'cpu': '2200', 'ram': '1024'}]
"""
list_data = []
list_data.append({})
d = list_data[-1]
lines = data.split('\n')
for line in lines:
line = line.strip()
if not line:
d = {}
list_data.append(d)
d = list_data[-1]
continue
whitespace = line.find(' ')
if not whitespace:
continue
key = line[0:whitespace]
value = line[whitespace + 1:]
d.update({key: value})
list_data = [val for val in list_data if val != {}]
return list_data
def str2list(data):
"""
Create a list of values from a whitespace and newline delimited text
(keys are ignored).
For example, this:
ip 1.2.3.4
ip 1.2.3.5
ip 1.2.3.6
becomes:
['1.2.3.4', '1.2.3.5', '1.2.3.6']
"""
list_data = []
for line in data.split('\n'):
line = line.strip()
if not line:
continue
try:
splitted = line.split(' ')
# key = splitted[0]
value = splitted[1]
except Exception:
continue
list_data.append(value)
return list_data
[docs]def dict2str(data):
"""
Create a string with a whitespace and newline delimited text from a
dictionary.
For example, this:
{'cpu': '1100', 'ram': '640', 'smp': 'auto'}
becomes:
cpu 1100
ram 640
smp auto
cpu 2200
ram 1024
"""
result = ''
for k in data:
if data[k] is not None:
result += '%s %s\n' % (str(k), str(data[k]))
else:
result += '%s\n' % str(k)
return result
[docs]def reverse_dict(dictionary):
return dict([(value, key) for key, value in list(dictionary.items())])
[docs]def lowercase_keys(dictionary):
return dict(((k.lower(), v) for k, v in dictionary.items()))
[docs]def get_secure_random_string(size):
"""
Return a string of ``size`` random bytes. Returned string is suitable for
cryptographic use.
:param size: Size of the generated string.
:type size: ``int``
:return: Random string.
:rtype: ``str``
"""
value = os.urandom(size)
value = binascii.hexlify(value)
value = value.decode('utf-8')[:size]
return value