deb-mistral/mistral/utils/__init__.py
Renat Akhmerov 97311a6c04 Refactor methods in utils related to dicts
* The previous versions of these methods were too specific for the
  general utils module. Now they are more generic thereby less
  confusing.

Change-Id: Ifa8bbf0cc8a63bf1de1142dc8c52b1f8ad3958c5
2017-03-13 19:07:47 +07:00

472 lines
12 KiB
Python

# Copyright 2013 - Mirantis, Inc.
# Copyright 2015 - Huawei Technologies Co. Ltd
# Copyright 2016 - Brocade Communications Systems, Inc.
#
# 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.
import contextlib
import functools
import json
import logging
import os
from os import path
import shutil
import socket
import sys
import tempfile
import threading
import eventlet
from eventlet import corolocal
from oslo_concurrency import processutils
from oslo_utils import timeutils
from oslo_utils import uuidutils
import pkg_resources as pkg
import random
from mistral import exceptions as exc
from mistral import version
# Thread local storage.
_th_loc_storage = threading.local()
ACTION_TASK_TYPE = 'ACTION'
WORKFLOW_TASK_TYPE = 'WORKFLOW'
def generate_unicode_uuid():
return uuidutils.generate_uuid()
def is_valid_uuid(uuid_string):
return uuidutils.is_uuid_like(uuid_string)
def _get_greenlet_local_storage():
greenlet_id = corolocal.get_ident()
greenlet_locals = getattr(_th_loc_storage, "greenlet_locals", None)
if not greenlet_locals:
greenlet_locals = {}
_th_loc_storage.greenlet_locals = greenlet_locals
if greenlet_id in greenlet_locals:
return greenlet_locals[greenlet_id]
else:
return None
def has_thread_local(var_name):
gl_storage = _get_greenlet_local_storage()
return gl_storage and var_name in gl_storage
def get_thread_local(var_name):
if not has_thread_local(var_name):
return None
return _get_greenlet_local_storage()[var_name]
def set_thread_local(var_name, val):
if val is None and has_thread_local(var_name):
gl_storage = _get_greenlet_local_storage()
# Delete variable from greenlet local storage.
if gl_storage:
del gl_storage[var_name]
# Delete the entire greenlet local storage from thread local storage.
if gl_storage and len(gl_storage) == 0:
del _th_loc_storage.greenlet_locals[corolocal.get_ident()]
if val is not None:
gl_storage = _get_greenlet_local_storage()
if not gl_storage:
gl_storage = _th_loc_storage.greenlet_locals[
corolocal.get_ident()] = {}
gl_storage[var_name] = val
def log_exec(logger, level=logging.DEBUG):
"""Decorator for logging function execution.
By default, target function execution is logged with DEBUG level.
"""
def _decorator(func):
@functools.wraps(func)
def _logged(*args, **kw):
params_repr = ("[args=%s, kw=%s]" % (str(args), str(kw))
if args or kw else "")
func_repr = ("Called method [name=%s, doc='%s', params=%s]" %
(func.__name__, func.__doc__, params_repr))
logger.log(level, func_repr)
return func(*args, **kw)
_logged.__doc__ = func.__doc__
return _logged
return _decorator
def merge_dicts(left, right, overwrite=True):
"""Merges two dictionaries.
Values of right dictionary recursively get merged into left dictionary.
:param left: Left dictionary.
:param right: Right dictionary.
:param overwrite: If False, left value will not be overwritten if exists.
"""
if left is None:
return right
if right is None:
return left
for k, v in right.items():
if k not in left:
left[k] = v
else:
left_v = left[k]
if isinstance(left_v, dict) and isinstance(v, dict):
merge_dicts(left_v, v, overwrite=overwrite)
elif overwrite:
left[k] = v
return left
def update_dict(left, right):
"""Updates left dict with content from right dict
:param left: Left dict.
:param right: Right dict.
:return: the updated left dictionary.
"""
if left is None:
return right
if right is None:
return left
left.update(right)
return left
def get_file_list(directory):
base_path = pkg.resource_filename(
version.version_info.package,
directory
)
return [path.join(base_path, f) for f in os.listdir(base_path)
if path.isfile(path.join(base_path, f))]
def cut_dict(d, length=100):
if not isinstance(d, dict):
raise ValueError("A dictionary is expected, got: %s" % type(d))
res = "{"
idx = 0
for key, value in d.items():
k = str(key)
v = str(value)
# Processing key.
new_len = len(res) + len(k)
is_str = isinstance(key, str)
if is_str:
new_len += 2
if new_len >= length:
res += "'%s..." % k[:length - new_len] if is_str else "%s..." % k
break
else:
res += "'%s'" % k if is_str else k
res += ": "
# Processing value.
new_len = len(res) + len(v)
is_str = isinstance(value, str)
if is_str:
new_len += 2
if new_len >= length:
res += "'%s..." % v[:length - new_len] if is_str else "%s..." % v
break
else:
res += "'%s'" % v if is_str else v
res += ', ' if idx < len(d) - 1 else '}'
if len(res) >= length:
res += '...'
break
idx += 1
return res
def cut_list(l, length=100):
if not isinstance(l, list):
raise ValueError("A list is expected, got: %s" % type(l))
res = '['
for idx, item in enumerate(l):
s = str(item)
new_len = len(res) + len(s)
is_str = isinstance(item, str)
if is_str:
new_len += 2
if new_len >= length:
res += "'%s..." % s[:length - new_len] if is_str else "%s..." % s
break
else:
res += "'%s'" % s if is_str else s
res += ', ' if idx < len(l) - 1 else ']'
return res
def cut_string(s, length=100):
if len(s) > length:
return "%s..." % s[:length]
return s
def cut(data, length=100):
if not data:
return data
if isinstance(data, list):
return cut_list(data, length=length)
if isinstance(data, dict):
return cut_dict(data, length=length)
return cut_string(str(data), length=length)
def cut_by_kb(data, kilobytes):
if kilobytes <= 0:
return cut(data)
bytes_per_char = sys.getsizeof('s') - sys.getsizeof('')
length = int(kilobytes * 1024 / bytes_per_char)
return cut(data, length)
def iter_subclasses(cls, _seen=None):
"""Generator over all subclasses of a given class in depth first order."""
if not isinstance(cls, type):
raise TypeError('iter_subclasses must be called with new-style class'
', not %.100r' % cls)
_seen = _seen or set()
try:
subs = cls.__subclasses__()
except TypeError: # fails only when cls is type
subs = cls.__subclasses__(cls)
for sub in subs:
if sub not in _seen:
_seen.add(sub)
yield sub
for _sub in iter_subclasses(sub, _seen):
yield _sub
def random_sleep(limit=1):
"""Sleeps for a random period of time not exceeding the given limit.
Mostly intended to be used by tests to emulate race conditions.
:param limit: Float number of seconds that a sleep period must not exceed.
"""
seconds = random.Random().randint(0, limit * 1000) * 0.001
print("Sleep: %s sec..." % seconds)
eventlet.sleep(seconds)
class NotDefined(object):
"""Marker of an empty value.
In a number of cases None can't be used to express the semantics of
a not defined value because None is just a normal value rather than
a value set to denote that it's not defined. This class can be used
in such cases instead of None.
"""
pass
def get_dict_from_string(string, delimiter=','):
if not string:
return {}
kv_dicts = []
for kv_pair_str in string.split(delimiter):
kv_str = kv_pair_str.strip()
kv_list = kv_str.split('=')
if len(kv_list) > 1:
try:
value = json.loads(kv_list[1])
except ValueError:
value = kv_list[1]
kv_dicts += [{kv_list[0]: value}]
else:
kv_dicts += [kv_list[0]]
return get_dict_from_entries(kv_dicts)
def get_dict_from_entries(entries):
"""Transforms a list of entries into dictionary.
:param entries: A list of entries.
If an entry is a dictionary the method simply updates the result
dictionary with its content.
If an entry is not a dict adds {entry, NotDefined} into the result.
"""
result = {}
for e in entries:
if isinstance(e, dict):
result.update(e)
else:
# NOTE(xylan): we put NotDefined here as the value of
# param without value specified, to distinguish from
# the valid values such as None, ''(empty string), etc.
result[e] = NotDefined
return result
def get_process_identifier():
"""Gets current running process identifier."""
return "%s_%s" % (socket.gethostname(), os.getpid())
@contextlib.contextmanager
def tempdir(**kwargs):
argdict = kwargs.copy()
if 'dir' not in argdict:
argdict['dir'] = '/tmp/'
tmpdir = tempfile.mkdtemp(**argdict)
try:
yield tmpdir
finally:
try:
shutil.rmtree(tmpdir)
except OSError as e:
raise exc.DataAccessException(
"Failed to delete temp dir %(dir)s (reason: %(reason)s)" %
{'dir': tmpdir, 'reason': e}
)
def save_text_to(text, file_path, overwrite=False):
if os.path.exists(file_path) and not overwrite:
raise exc.DataAccessException(
"Cannot save data to file. File %s already exists."
)
with open(file_path, 'w') as f:
f.write(text)
def generate_key_pair(key_length=2048):
"""Create RSA key pair with specified number of bits in key.
Returns tuple of private and public keys.
"""
with tempdir() as tmpdir:
keyfile = os.path.join(tmpdir, 'tempkey')
args = [
'ssh-keygen',
'-q', # quiet
'-N', '', # w/o passphrase
'-t', 'rsa', # create key of rsa type
'-f', keyfile, # filename of the key file
'-C', 'Generated-by-Mistral' # key comment
]
if key_length is not None:
args.extend(['-b', key_length])
processutils.execute(*args)
if not os.path.exists(keyfile):
raise exc.DataAccessException(
"Private key file hasn't been created"
)
private_key = open(keyfile).read()
public_key_path = keyfile + '.pub'
if not os.path.exists(public_key_path):
raise exc.DataAccessException(
"Public key file hasn't been created"
)
public_key = open(public_key_path).read()
return private_key, public_key
def utc_now_sec():
"""Returns current time and drops microseconds."""
d = timeutils.utcnow()
return d.replace(microsecond=0)