cinder.utils module¶
Utilities and helper functions for all Cinder code.
This file is for utilities useful in all of Cinder, including cinder-manage, the api service, the scheduler, etc.
Code related to volume drivers and connecting to volumes should be placed in volume_utils instead.
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class
ComparableMixin
¶ Bases:
object
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DO_NOTHING
¶ Class that literrally does nothing.
We inherit from str in case it’s called with json.dumps.
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class
DoNothing
¶ Bases:
str
Class that literrally does nothing.
We inherit from str in case it’s called with json.dumps.
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class
Semaphore
(limit)¶ Bases:
object
Custom semaphore to workaround eventlet issues with multiprocessing.
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api_clean_volume_file_locks
(volume_id)¶
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as_int
(obj: Union[int, float, str], quiet: bool = True) → int¶
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build_or_str
(elements: Union[None, str, Iterable[str]], str_format: Optional[str] = None) → str¶ Builds a string of elements joined by ‘or’.
Will join strings with the ‘or’ word and if a str_format is provided it will be used to format the resulted joined string. If there are no elements an empty string will be returned.
- Parameters
elements (String or iterable of strings.) – Elements we want to join.
str_format (String.) – String to use to format the response.
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calculate_max_over_subscription_ratio
(capability: dict, global_max_over_subscription_ratio: float) → float¶
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calculate_virtual_free_capacity
(total_capacity: float, free_capacity: float, provisioned_capacity: float, thin_provisioning_support: bool, max_over_subscription_ratio: float, reserved_percentage: float, thin: bool) → float¶ Calculate the virtual free capacity based on thin provisioning support.
- Parameters
total_capacity – total_capacity_gb of a host_state or pool.
free_capacity – free_capacity_gb of a host_state or pool.
provisioned_capacity – provisioned_capacity_gb of a host_state or pool.
thin_provisioning_support – thin_provisioning_support of a host_state or a pool.
max_over_subscription_ratio – max_over_subscription_ratio of a host_state or a pool
reserved_percentage – reserved_percentage of a host_state or a pool.
thin – whether volume to be provisioned is thin
- Returns
the calculated virtual free capacity.
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check_exclusive_options
(**kwargs: Optional[Union[dict, str, bool]]) → None¶ Checks that only one of the provided options is actually not-none.
Iterates over all the kwargs passed in and checks that only one of said arguments is not-none, if more than one is not-none then an exception will be raised with the names of those arguments who were not-none.
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check_metadata_properties
(metadata: Optional[Dict[str, str]]) → None¶ Checks that the volume metadata properties are valid.
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check_ssh_injection
(cmd_list: List[str]) → None¶
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check_string_length
(value: str, name: str, min_length: int = 0, max_length: Optional[int] = None, allow_all_spaces: bool = True) → None¶ Check the length of specified string.
- Parameters
value – the value of the string
name – the name of the string
min_length – the min_length of the string
max_length – the max_length of the string
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clean_snapshot_file_locks
(snapshot_id, driver)¶
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clean_volume_file_locks
(volume_id, driver)¶ Remove file locks used by Cinder.
This doesn’t take care of driver locks, those should be handled in driver’s delete_volume method.
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convert_str
(text: Union[str, bytes]) → str¶ Convert to native string.
Convert bytes and Unicode strings to native strings:
convert to bytes on Python 2: encode Unicode using encodeutils.safe_encode()
convert to Unicode on Python 3: decode bytes from UTF-8
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create_ordereddict
(adict: dict) → collections.OrderedDict¶ Given a dict, return a sorted OrderedDict.
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execute
(*cmd: str, **kwargs: Union[bool, str]) → Tuple[str, str]¶ Convenience wrapper around oslo’s execute() method.
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get_blkdev_major_minor
(path: str, lookup_for_file: bool = True) → Optional[str]¶ Get ‘major:minor’ number of block device.
Get the device’s ‘major:minor’ number of a block device to control I/O ratelimit of the specified path. If lookup_for_file is True and the path is a regular file, lookup a disk device which the file lies on and returns the result for the device.
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get_bool_param
(param_string: str, params: dict, default: bool = False) → bool¶
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get_file_gid
(path: str) → int¶ This primarily exists to make unit testing easier.
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get_file_mode
(path: str) → int¶ This primarily exists to make unit testing easier.
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get_file_size
(path: str) → int¶ Returns the file size.
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get_log_levels
(prefix: str) → dict¶
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get_log_method
(level_string: str) → int¶
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get_root_helper
() → str¶
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if_notifications_enabled
(f: Callable) → Callable¶ Calls decorated method only if notifications are enabled.
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is_blk_device
(dev: str) → bool¶
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last_completed_audit_period
(unit: Optional[str] = None) → Tuple[Union[datetime.datetime, datetime.timedelta], Union[datetime.datetime, datetime.timedelta]]¶ This method gives you the most recently completed audit period.
- arguments:
- units: string, one of ‘hour’, ‘day’, ‘month’, ‘year’
Periods normally begin at the beginning (UTC) of the period unit (So a ‘day’ period begins at midnight UTC, a ‘month’ unit on the 1st, a ‘year’ on Jan, 1) unit string may be appended with an optional offset like so: ‘day@18’ This will begin the period at 18:00 UTC. ‘month@15’ starts a monthly period on the 15th, and year@3 begins a yearly one on March 1st.
- returns: 2 tuple of datetimes (begin, end)
The begin timestamp of this audit period is the same as the end of the previous.
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limit_operations
(func: Callable) → Callable¶ Decorator to limit the number of concurrent operations.
This method decorator expects to have a _semaphore attribute holding an initialized semaphore in the self instance object.
We can get the appropriate semaphore with the semaphore_factory method.
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make_dev_path
(dev: str, partition: Optional[str] = None, base: str = '/dev') → str¶ Return a path to a particular device.
>>> make_dev_path('xvdc') /dev/xvdc
>>> make_dev_path('xvdc', 1) /dev/xvdc1
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monkey_patch
() → None¶ Patches decorators for all functions in a specified module.
If the CONF.monkey_patch set as True, this function patches a decorator for all functions in specified modules.
You can set decorators for each modules using CONF.monkey_patch_modules. The format is “Module path:Decorator function”. Example: ‘cinder.api.ec2.cloud:’ cinder.openstack.common.notifier.api.notify_decorator’
Parameters of the decorator are as follows. (See cinder.openstack.common.notifier.api.notify_decorator)
- Parameters
name – name of the function
function – object of the function
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notifications_enabled
(conf)¶ Check if oslo notifications are enabled.
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paths_normcase_equal
(path_a: str, path_b: str) → bool¶
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retry
(retry_param: Optional[Type[Exception]], interval: int = 1, retries: int = 3, backoff_rate: int = 2, wait_random: bool = False, retry=<class 'tenacity.retry.retry_if_exception_type'>) → Callable¶
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class
retry_if_exit_code
(codes)¶ Bases:
tenacity.retry.retry_if_exception
Retry on ProcessExecutionError specific exit codes.
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robust_file_write
(directory: str, filename: str, data: str) → None¶ Robust file write.
Use “write to temp file and rename” model for writing the persistence file.
- Parameters
directory – Target directory to create a file.
filename – File name to store specified data.
data – String data.
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semaphore_factory
(limit: int, concurrent_processes: int) → Union[eventlet.semaphore.Semaphore, cinder.utils.Semaphore]¶ Get a semaphore to limit concurrent operations.
The semaphore depends on the limit we want to set and the concurrent processes that need to be limited.
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service_expired_time
(with_timezone: Optional[bool] = False) → datetime.datetime¶
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set_log_levels
(prefix: str, level_string: str) → None¶
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tempdir
(**kwargs) → Iterator[str]¶
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temporary_chown
(path: str, owner_uid: int = None) → Iterator[None]¶ Temporarily chown a path.
- Params owner_uid
UID of temporary owner (defaults to current user)
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validate_dictionary_string_length
(specs: dict) → None¶ Check the length of each key and value of dictionary.