atef.check.DynamicValue

class atef.check.DynamicValue(value: str | int | bool | float | None = None, reduce_period: int | float | None = None, reduce_method: ReduceMethod = ReduceMethod.average, string: bool | None = None)

A primitive value from an external source that may change over time. This necessarily picks up a runtime performance cost and getting the value is not guaranteed to be successful. If unsuccessful, this will raise a DynamicValueError from the original exception.

Includes settings for reduction of multiple samples.

Value will be cached on preparation, and this value used for comparisons

Attributes:

reduce_period

string

value

Methods

get()	Return the cached value from prepare, or raise a DynamicValueError if there is no such value.
prepare(cache)	Implement in child class to get the current value from source.

Methods

__init__(value: str | int | bool | float | None = None, reduce_period: int | float | None = None, reduce_method: ReduceMethod = ReduceMethod.average, string: bool | None = None) → None

get() → str | int | bool | float

Return the cached value from prepare, or raise a DynamicValueError if there is no such value.

async prepare(cache: DataCache) → None

Implement in child class to get the current value from source. Should set the self.value

Attributes

reduce_method: ReduceMethod = 'average'

Reduce collected samples by this reduce method

reduce_period: int | float | None = None

Period over which the value will be read

string: bool | None = None

If applicable, request and compare string values rather than the default

value: str | int | bool | float | None = None

Value is now optional, and will be filled in when prepared