python-sdk/openfeature/client.py

979 lines
34 KiB
Python

import logging
import typing
from collections.abc import Awaitable, Sequence
from dataclasses import dataclass
from openfeature import _event_support
from openfeature.evaluation_context import EvaluationContext, get_evaluation_context
from openfeature.event import EventHandler, ProviderEvent
from openfeature.exception import (
ErrorCode,
GeneralError,
OpenFeatureError,
ProviderFatalError,
ProviderNotReadyError,
TypeMismatchError,
)
from openfeature.flag_evaluation import (
FlagEvaluationDetails,
FlagEvaluationOptions,
FlagResolutionDetails,
FlagType,
FlagValueType,
Reason,
)
from openfeature.hook import Hook, HookContext, HookHints, get_hooks
from openfeature.hook._hook_support import (
after_all_hooks,
after_hooks,
before_hooks,
error_hooks,
)
from openfeature.provider import FeatureProvider, ProviderStatus
from openfeature.provider._registry import provider_registry
from openfeature.transaction_context import get_transaction_context
__all__ = [
"ClientMetadata",
"OpenFeatureClient",
]
logger = logging.getLogger("openfeature")
TypeMap = dict[
FlagType,
typing.Union[
type[bool],
type[int],
type[float],
type[str],
tuple[type[dict], type[list]],
],
]
T = typing.TypeVar("T", bool, int, float, str, typing.Union[dict, list])
class ResolveDetailsCallable(typing.Protocol[T]):
def __call__(
self,
flag_key: str,
default_value: T,
evaluation_context: typing.Optional[EvaluationContext],
) -> FlagResolutionDetails[T]: ...
class ResolveDetailsCallableAsync(typing.Protocol[T]):
def __call__(
self,
flag_key: str,
default_value: T,
evaluation_context: typing.Optional[EvaluationContext],
) -> Awaitable[FlagResolutionDetails[T]]: ...
@dataclass
class ClientMetadata:
name: typing.Optional[str] = None
domain: typing.Optional[str] = None
class OpenFeatureClient:
def __init__(
self,
domain: typing.Optional[str],
version: typing.Optional[str],
context: typing.Optional[EvaluationContext] = None,
hooks: typing.Optional[list[Hook]] = None,
) -> None:
self.domain = domain
self.version = version
self.context = context or EvaluationContext()
self.hooks = hooks or []
@property
def provider(self) -> FeatureProvider:
return provider_registry.get_provider(self.domain)
def get_provider_status(self) -> ProviderStatus:
return provider_registry.get_provider_status(self.provider)
def get_metadata(self) -> ClientMetadata:
return ClientMetadata(domain=self.domain)
def add_hooks(self, hooks: list[Hook]) -> None:
self.hooks = self.hooks + hooks
def get_boolean_value(
self,
flag_key: str,
default_value: bool,
evaluation_context: typing.Optional[EvaluationContext] = None,
flag_evaluation_options: typing.Optional[FlagEvaluationOptions] = None,
) -> bool:
return self.get_boolean_details(
flag_key,
default_value,
evaluation_context,
flag_evaluation_options,
).value
async def get_boolean_value_async(
self,
flag_key: str,
default_value: bool,
evaluation_context: typing.Optional[EvaluationContext] = None,
flag_evaluation_options: typing.Optional[FlagEvaluationOptions] = None,
) -> bool:
details = await self.get_boolean_details_async(
flag_key,
default_value,
evaluation_context,
flag_evaluation_options,
)
return details.value
def get_boolean_details(
self,
flag_key: str,
default_value: bool,
evaluation_context: typing.Optional[EvaluationContext] = None,
flag_evaluation_options: typing.Optional[FlagEvaluationOptions] = None,
) -> FlagEvaluationDetails[bool]:
return self.evaluate_flag_details(
FlagType.BOOLEAN,
flag_key,
default_value,
evaluation_context,
flag_evaluation_options,
)
async def get_boolean_details_async(
self,
flag_key: str,
default_value: bool,
evaluation_context: typing.Optional[EvaluationContext] = None,
flag_evaluation_options: typing.Optional[FlagEvaluationOptions] = None,
) -> FlagEvaluationDetails[bool]:
return await self.evaluate_flag_details_async(
FlagType.BOOLEAN,
flag_key,
default_value,
evaluation_context,
flag_evaluation_options,
)
def get_string_value(
self,
flag_key: str,
default_value: str,
evaluation_context: typing.Optional[EvaluationContext] = None,
flag_evaluation_options: typing.Optional[FlagEvaluationOptions] = None,
) -> str:
return self.get_string_details(
flag_key,
default_value,
evaluation_context,
flag_evaluation_options,
).value
async def get_string_value_async(
self,
flag_key: str,
default_value: str,
evaluation_context: typing.Optional[EvaluationContext] = None,
flag_evaluation_options: typing.Optional[FlagEvaluationOptions] = None,
) -> str:
details = await self.get_string_details_async(
flag_key,
default_value,
evaluation_context,
flag_evaluation_options,
)
return details.value
def get_string_details(
self,
flag_key: str,
default_value: str,
evaluation_context: typing.Optional[EvaluationContext] = None,
flag_evaluation_options: typing.Optional[FlagEvaluationOptions] = None,
) -> FlagEvaluationDetails[str]:
return self.evaluate_flag_details(
FlagType.STRING,
flag_key,
default_value,
evaluation_context,
flag_evaluation_options,
)
async def get_string_details_async(
self,
flag_key: str,
default_value: str,
evaluation_context: typing.Optional[EvaluationContext] = None,
flag_evaluation_options: typing.Optional[FlagEvaluationOptions] = None,
) -> FlagEvaluationDetails[str]:
return await self.evaluate_flag_details_async(
FlagType.STRING,
flag_key,
default_value,
evaluation_context,
flag_evaluation_options,
)
def get_integer_value(
self,
flag_key: str,
default_value: int,
evaluation_context: typing.Optional[EvaluationContext] = None,
flag_evaluation_options: typing.Optional[FlagEvaluationOptions] = None,
) -> int:
return self.get_integer_details(
flag_key,
default_value,
evaluation_context,
flag_evaluation_options,
).value
async def get_integer_value_async(
self,
flag_key: str,
default_value: int,
evaluation_context: typing.Optional[EvaluationContext] = None,
flag_evaluation_options: typing.Optional[FlagEvaluationOptions] = None,
) -> int:
details = await self.get_integer_details_async(
flag_key,
default_value,
evaluation_context,
flag_evaluation_options,
)
return details.value
def get_integer_details(
self,
flag_key: str,
default_value: int,
evaluation_context: typing.Optional[EvaluationContext] = None,
flag_evaluation_options: typing.Optional[FlagEvaluationOptions] = None,
) -> FlagEvaluationDetails[int]:
return self.evaluate_flag_details(
FlagType.INTEGER,
flag_key,
default_value,
evaluation_context,
flag_evaluation_options,
)
async def get_integer_details_async(
self,
flag_key: str,
default_value: int,
evaluation_context: typing.Optional[EvaluationContext] = None,
flag_evaluation_options: typing.Optional[FlagEvaluationOptions] = None,
) -> FlagEvaluationDetails[int]:
return await self.evaluate_flag_details_async(
FlagType.INTEGER,
flag_key,
default_value,
evaluation_context,
flag_evaluation_options,
)
def get_float_value(
self,
flag_key: str,
default_value: float,
evaluation_context: typing.Optional[EvaluationContext] = None,
flag_evaluation_options: typing.Optional[FlagEvaluationOptions] = None,
) -> float:
return self.get_float_details(
flag_key,
default_value,
evaluation_context,
flag_evaluation_options,
).value
async def get_float_value_async(
self,
flag_key: str,
default_value: float,
evaluation_context: typing.Optional[EvaluationContext] = None,
flag_evaluation_options: typing.Optional[FlagEvaluationOptions] = None,
) -> float:
details = await self.get_float_details_async(
flag_key,
default_value,
evaluation_context,
flag_evaluation_options,
)
return details.value
def get_float_details(
self,
flag_key: str,
default_value: float,
evaluation_context: typing.Optional[EvaluationContext] = None,
flag_evaluation_options: typing.Optional[FlagEvaluationOptions] = None,
) -> FlagEvaluationDetails[float]:
return self.evaluate_flag_details(
FlagType.FLOAT,
flag_key,
default_value,
evaluation_context,
flag_evaluation_options,
)
async def get_float_details_async(
self,
flag_key: str,
default_value: float,
evaluation_context: typing.Optional[EvaluationContext] = None,
flag_evaluation_options: typing.Optional[FlagEvaluationOptions] = None,
) -> FlagEvaluationDetails[float]:
return await self.evaluate_flag_details_async(
FlagType.FLOAT,
flag_key,
default_value,
evaluation_context,
flag_evaluation_options,
)
def get_object_value(
self,
flag_key: str,
default_value: typing.Union[
Sequence[FlagValueType], typing.Mapping[str, FlagValueType]
],
evaluation_context: typing.Optional[EvaluationContext] = None,
flag_evaluation_options: typing.Optional[FlagEvaluationOptions] = None,
) -> typing.Union[Sequence[FlagValueType], typing.Mapping[str, FlagValueType]]:
return self.get_object_details(
flag_key,
default_value,
evaluation_context,
flag_evaluation_options,
).value
async def get_object_value_async(
self,
flag_key: str,
default_value: typing.Union[
Sequence[FlagValueType], typing.Mapping[str, FlagValueType]
],
evaluation_context: typing.Optional[EvaluationContext] = None,
flag_evaluation_options: typing.Optional[FlagEvaluationOptions] = None,
) -> typing.Union[Sequence[FlagValueType], typing.Mapping[str, FlagValueType]]:
details = await self.get_object_details_async(
flag_key,
default_value,
evaluation_context,
flag_evaluation_options,
)
return details.value
def get_object_details(
self,
flag_key: str,
default_value: typing.Union[
Sequence[FlagValueType], typing.Mapping[str, FlagValueType]
],
evaluation_context: typing.Optional[EvaluationContext] = None,
flag_evaluation_options: typing.Optional[FlagEvaluationOptions] = None,
) -> FlagEvaluationDetails[
typing.Union[Sequence[FlagValueType], typing.Mapping[str, FlagValueType]]
]:
return self.evaluate_flag_details(
FlagType.OBJECT,
flag_key,
default_value,
evaluation_context,
flag_evaluation_options,
)
async def get_object_details_async(
self,
flag_key: str,
default_value: typing.Union[
Sequence[FlagValueType], typing.Mapping[str, FlagValueType]
],
evaluation_context: typing.Optional[EvaluationContext] = None,
flag_evaluation_options: typing.Optional[FlagEvaluationOptions] = None,
) -> FlagEvaluationDetails[
typing.Union[Sequence[FlagValueType], typing.Mapping[str, FlagValueType]]
]:
return await self.evaluate_flag_details_async(
FlagType.OBJECT,
flag_key,
default_value,
evaluation_context,
flag_evaluation_options,
)
def _establish_hooks_and_provider(
self,
flag_type: FlagType,
flag_key: str,
default_value: FlagValueType,
evaluation_context: typing.Optional[EvaluationContext],
flag_evaluation_options: typing.Optional[FlagEvaluationOptions],
) -> tuple[
FeatureProvider,
HookContext,
HookHints,
list[Hook],
list[Hook],
]:
if evaluation_context is None:
evaluation_context = EvaluationContext()
if flag_evaluation_options is None:
flag_evaluation_options = FlagEvaluationOptions()
provider = self.provider # call this once to maintain a consistent reference
evaluation_hooks = flag_evaluation_options.hooks
hook_hints = flag_evaluation_options.hook_hints
# Merge transaction context into evaluation context before creating hook_context
# This ensures hooks have access to the complete context including transaction context
merged_eval_context = (
get_evaluation_context()
.merge(get_transaction_context())
.merge(self.context)
.merge(evaluation_context)
)
hook_context = HookContext(
flag_key=flag_key,
flag_type=flag_type,
default_value=default_value,
evaluation_context=merged_eval_context,
client_metadata=self.get_metadata(),
provider_metadata=provider.get_metadata(),
)
# Hooks need to be handled in different orders at different stages
# in the flag evaluation
# before: API, Client, Invocation, Provider
merged_hooks = (
get_hooks() + self.hooks + evaluation_hooks + provider.get_provider_hooks()
)
# after, error, finally: Provider, Invocation, Client, API
reversed_merged_hooks = merged_hooks[:]
reversed_merged_hooks.reverse()
return provider, hook_context, hook_hints, merged_hooks, reversed_merged_hooks
def _assert_provider_status(
self,
) -> typing.Optional[OpenFeatureError]:
status = self.get_provider_status()
if status == ProviderStatus.NOT_READY:
return ProviderNotReadyError()
if status == ProviderStatus.FATAL:
return ProviderFatalError()
return None
def _run_before_hooks_and_update_context(
self,
flag_type: FlagType,
hook_context: HookContext,
merged_hooks: list[Hook],
hook_hints: HookHints,
evaluation_context: typing.Optional[EvaluationContext],
) -> EvaluationContext:
# https://github.com/open-feature/spec/blob/main/specification/sections/03-evaluation-context.md
# Any resulting evaluation context from a before hook will overwrite
# duplicate fields defined globally, on the client, or in the invocation.
# Requirement 3.2.2, 4.3.4: API.context->client.context->invocation.context
before_hooks_context = before_hooks(
flag_type, hook_context, merged_hooks, hook_hints
)
# The hook_context.evaluation_context already contains the merged context from
# _establish_hooks_and_provider, so we just need to merge with the before hooks result
merged_context = hook_context.evaluation_context.merge(before_hooks_context)
return merged_context
@typing.overload
async def evaluate_flag_details_async(
self,
flag_type: FlagType,
flag_key: str,
default_value: bool,
evaluation_context: typing.Optional[EvaluationContext] = None,
flag_evaluation_options: typing.Optional[FlagEvaluationOptions] = None,
) -> FlagEvaluationDetails[bool]: ...
@typing.overload
async def evaluate_flag_details_async(
self,
flag_type: FlagType,
flag_key: str,
default_value: int,
evaluation_context: typing.Optional[EvaluationContext] = None,
flag_evaluation_options: typing.Optional[FlagEvaluationOptions] = None,
) -> FlagEvaluationDetails[int]: ...
@typing.overload
async def evaluate_flag_details_async(
self,
flag_type: FlagType,
flag_key: str,
default_value: float,
evaluation_context: typing.Optional[EvaluationContext] = None,
flag_evaluation_options: typing.Optional[FlagEvaluationOptions] = None,
) -> FlagEvaluationDetails[float]: ...
@typing.overload
async def evaluate_flag_details_async(
self,
flag_type: FlagType,
flag_key: str,
default_value: str,
evaluation_context: typing.Optional[EvaluationContext] = None,
flag_evaluation_options: typing.Optional[FlagEvaluationOptions] = None,
) -> FlagEvaluationDetails[str]: ...
@typing.overload
async def evaluate_flag_details_async(
self,
flag_type: FlagType,
flag_key: str,
default_value: Sequence["FlagValueType"],
evaluation_context: typing.Optional[EvaluationContext] = None,
flag_evaluation_options: typing.Optional[FlagEvaluationOptions] = None,
) -> FlagEvaluationDetails[Sequence["FlagValueType"]]: ...
@typing.overload
async def evaluate_flag_details_async(
self,
flag_type: FlagType,
flag_key: str,
default_value: typing.Mapping[str, "FlagValueType"],
evaluation_context: typing.Optional[EvaluationContext] = None,
flag_evaluation_options: typing.Optional[FlagEvaluationOptions] = None,
) -> FlagEvaluationDetails[typing.Mapping[str, "FlagValueType"]]: ...
async def evaluate_flag_details_async(
self,
flag_type: FlagType,
flag_key: str,
default_value: FlagValueType,
evaluation_context: typing.Optional[EvaluationContext] = None,
flag_evaluation_options: typing.Optional[FlagEvaluationOptions] = None,
) -> FlagEvaluationDetails[FlagValueType]:
"""
Evaluate the flag requested by the user from the clients provider.
:param flag_type: the type of the flag being returned
:param flag_key: the string key of the selected flag
:param default_value: backup value returned if no result found by the provider
:param evaluation_context: Information for the purposes of flag evaluation
:param flag_evaluation_options: Additional flag evaluation information
:return: a typing.Awaitable[FlagEvaluationDetails] object with the fully evaluated flag from a
provider
"""
provider, hook_context, hook_hints, merged_hooks, reversed_merged_hooks = (
self._establish_hooks_and_provider(
flag_type,
flag_key,
default_value,
evaluation_context,
flag_evaluation_options,
)
)
try:
if provider_err := self._assert_provider_status():
error_hooks(
flag_type,
hook_context,
provider_err,
reversed_merged_hooks,
hook_hints,
)
flag_evaluation = FlagEvaluationDetails(
flag_key=flag_key,
value=default_value,
reason=Reason.ERROR,
error_code=provider_err.error_code,
error_message=provider_err.error_message,
)
return flag_evaluation
merged_context = self._run_before_hooks_and_update_context(
flag_type,
hook_context,
merged_hooks,
hook_hints,
evaluation_context,
)
flag_evaluation = await self._create_provider_evaluation_async(
provider,
flag_type,
flag_key,
default_value,
merged_context,
)
if err := flag_evaluation.get_exception():
error_hooks(
flag_type, hook_context, err, reversed_merged_hooks, hook_hints
)
return flag_evaluation
after_hooks(
flag_type,
hook_context,
flag_evaluation,
reversed_merged_hooks,
hook_hints,
)
return flag_evaluation
except OpenFeatureError as err:
error_hooks(flag_type, hook_context, err, reversed_merged_hooks, hook_hints)
flag_evaluation = FlagEvaluationDetails(
flag_key=flag_key,
value=default_value,
reason=Reason.ERROR,
error_code=err.error_code,
error_message=err.error_message,
)
return flag_evaluation
# Catch any type of exception here since the user can provide any exception
# in the error hooks
except Exception as err: # pragma: no cover
logger.exception(
"Unable to correctly evaluate flag with key: '%s'", flag_key
)
error_hooks(flag_type, hook_context, err, reversed_merged_hooks, hook_hints)
error_message = getattr(err, "error_message", str(err))
flag_evaluation = FlagEvaluationDetails(
flag_key=flag_key,
value=default_value,
reason=Reason.ERROR,
error_code=ErrorCode.GENERAL,
error_message=error_message,
)
return flag_evaluation
finally:
after_all_hooks(
flag_type,
hook_context,
flag_evaluation,
reversed_merged_hooks,
hook_hints,
)
@typing.overload
def evaluate_flag_details(
self,
flag_type: FlagType,
flag_key: str,
default_value: bool,
evaluation_context: typing.Optional[EvaluationContext] = None,
flag_evaluation_options: typing.Optional[FlagEvaluationOptions] = None,
) -> FlagEvaluationDetails[bool]: ...
@typing.overload
def evaluate_flag_details(
self,
flag_type: FlagType,
flag_key: str,
default_value: int,
evaluation_context: typing.Optional[EvaluationContext] = None,
flag_evaluation_options: typing.Optional[FlagEvaluationOptions] = None,
) -> FlagEvaluationDetails[int]: ...
@typing.overload
def evaluate_flag_details(
self,
flag_type: FlagType,
flag_key: str,
default_value: float,
evaluation_context: typing.Optional[EvaluationContext] = None,
flag_evaluation_options: typing.Optional[FlagEvaluationOptions] = None,
) -> FlagEvaluationDetails[float]: ...
@typing.overload
def evaluate_flag_details(
self,
flag_type: FlagType,
flag_key: str,
default_value: str,
evaluation_context: typing.Optional[EvaluationContext] = None,
flag_evaluation_options: typing.Optional[FlagEvaluationOptions] = None,
) -> FlagEvaluationDetails[str]: ...
@typing.overload
def evaluate_flag_details(
self,
flag_type: FlagType,
flag_key: str,
default_value: Sequence["FlagValueType"],
evaluation_context: typing.Optional[EvaluationContext] = None,
flag_evaluation_options: typing.Optional[FlagEvaluationOptions] = None,
) -> FlagEvaluationDetails[Sequence["FlagValueType"]]: ...
@typing.overload
def evaluate_flag_details(
self,
flag_type: FlagType,
flag_key: str,
default_value: typing.Mapping[str, "FlagValueType"],
evaluation_context: typing.Optional[EvaluationContext] = None,
flag_evaluation_options: typing.Optional[FlagEvaluationOptions] = None,
) -> FlagEvaluationDetails[typing.Mapping[str, "FlagValueType"]]: ...
def evaluate_flag_details(
self,
flag_type: FlagType,
flag_key: str,
default_value: FlagValueType,
evaluation_context: typing.Optional[EvaluationContext] = None,
flag_evaluation_options: typing.Optional[FlagEvaluationOptions] = None,
) -> FlagEvaluationDetails[FlagValueType]:
"""
Evaluate the flag requested by the user from the clients provider.
:param flag_type: the type of the flag being returned
:param flag_key: the string key of the selected flag
:param default_value: backup value returned if no result found by the provider
:param evaluation_context: Information for the purposes of flag evaluation
:param flag_evaluation_options: Additional flag evaluation information
:return: a FlagEvaluationDetails object with the fully evaluated flag from a
provider
"""
provider, hook_context, hook_hints, merged_hooks, reversed_merged_hooks = (
self._establish_hooks_and_provider(
flag_type,
flag_key,
default_value,
evaluation_context,
flag_evaluation_options,
)
)
try:
if provider_err := self._assert_provider_status():
error_hooks(
flag_type,
hook_context,
provider_err,
reversed_merged_hooks,
hook_hints,
)
flag_evaluation = FlagEvaluationDetails(
flag_key=flag_key,
value=default_value,
reason=Reason.ERROR,
error_code=provider_err.error_code,
error_message=provider_err.error_message,
)
return flag_evaluation
merged_context = self._run_before_hooks_and_update_context(
flag_type,
hook_context,
merged_hooks,
hook_hints,
evaluation_context,
)
flag_evaluation = self._create_provider_evaluation(
provider,
flag_type,
flag_key,
default_value,
merged_context,
)
if err := flag_evaluation.get_exception():
error_hooks(
flag_type, hook_context, err, reversed_merged_hooks, hook_hints
)
flag_evaluation.value = default_value
return flag_evaluation
after_hooks(
flag_type,
hook_context,
flag_evaluation,
reversed_merged_hooks,
hook_hints,
)
return flag_evaluation
except OpenFeatureError as err:
error_hooks(flag_type, hook_context, err, reversed_merged_hooks, hook_hints)
flag_evaluation = FlagEvaluationDetails(
flag_key=flag_key,
value=default_value,
reason=Reason.ERROR,
error_code=err.error_code,
error_message=err.error_message,
)
return flag_evaluation
# Catch any type of exception here since the user can provide any exception
# in the error hooks
except Exception as err: # pragma: no cover
logger.exception(
"Unable to correctly evaluate flag with key: '%s'", flag_key
)
error_hooks(flag_type, hook_context, err, reversed_merged_hooks, hook_hints)
error_message = getattr(err, "error_message", str(err))
flag_evaluation = FlagEvaluationDetails(
flag_key=flag_key,
value=default_value,
reason=Reason.ERROR,
error_code=ErrorCode.GENERAL,
error_message=error_message,
)
return flag_evaluation
finally:
after_all_hooks(
flag_type,
hook_context,
flag_evaluation,
reversed_merged_hooks,
hook_hints,
)
async def _create_provider_evaluation_async(
self,
provider: FeatureProvider,
flag_type: FlagType,
flag_key: str,
default_value: FlagValueType,
evaluation_context: typing.Optional[EvaluationContext] = None,
) -> FlagEvaluationDetails[FlagValueType]:
get_details_callables_async: typing.Mapping[
FlagType, ResolveDetailsCallableAsync
] = {
FlagType.BOOLEAN: provider.resolve_boolean_details_async,
FlagType.INTEGER: provider.resolve_integer_details_async,
FlagType.FLOAT: provider.resolve_float_details_async,
FlagType.OBJECT: provider.resolve_object_details_async,
FlagType.STRING: provider.resolve_string_details_async,
}
get_details_callable = get_details_callables_async.get(flag_type)
if not get_details_callable:
return FlagEvaluationDetails(
flag_key=flag_key,
value=default_value,
reason=Reason.ERROR,
error_code=ErrorCode.GENERAL,
error_message="Unknown flag type",
)
resolution = await get_details_callable(
flag_key=flag_key,
default_value=default_value,
evaluation_context=evaluation_context,
)
if resolution.error_code:
return resolution.to_flag_evaluation_details(flag_key)
# we need to check the get_args to be compatible with union types.
if err := _typecheck_flag_value(value=resolution.value, flag_type=flag_type):
return FlagEvaluationDetails(
flag_key=flag_key,
value=resolution.value,
reason=Reason.ERROR,
error_code=err.error_code,
error_message=err.error_message,
)
return resolution.to_flag_evaluation_details(flag_key)
def _create_provider_evaluation(
self,
provider: FeatureProvider,
flag_type: FlagType,
flag_key: str,
default_value: FlagValueType,
evaluation_context: typing.Optional[EvaluationContext] = None,
) -> FlagEvaluationDetails[FlagValueType]:
"""
Encapsulated method to create a FlagEvaluationDetail from a specific provider.
:param flag_type: the type of the flag being returned
:param key: the string key of the selected flag
:param default_value: backup value returned if no result found by the provider
:param evaluation_context: Information for the purposes of flag evaluation
:return: a FlagEvaluationDetails object with the fully evaluated flag from a
provider
"""
get_details_callables: typing.Mapping[FlagType, ResolveDetailsCallable] = {
FlagType.BOOLEAN: provider.resolve_boolean_details,
FlagType.INTEGER: provider.resolve_integer_details,
FlagType.FLOAT: provider.resolve_float_details,
FlagType.OBJECT: provider.resolve_object_details,
FlagType.STRING: provider.resolve_string_details,
}
get_details_callable = get_details_callables.get(flag_type)
if not get_details_callable:
return FlagEvaluationDetails(
flag_key=flag_key,
value=default_value,
reason=Reason.ERROR,
error_code=ErrorCode.GENERAL,
error_message="Unknown flag type",
)
resolution = get_details_callable(
flag_key=flag_key,
default_value=default_value,
evaluation_context=evaluation_context,
)
if resolution.error_code:
return resolution.to_flag_evaluation_details(flag_key)
# we need to check the get_args to be compatible with union types.
if err := _typecheck_flag_value(value=resolution.value, flag_type=flag_type):
return FlagEvaluationDetails(
flag_key=flag_key,
value=resolution.value,
reason=Reason.ERROR,
error_code=err.error_code,
error_message=err.error_message,
)
return resolution.to_flag_evaluation_details(flag_key)
def add_handler(self, event: ProviderEvent, handler: EventHandler) -> None:
_event_support.add_client_handler(self, event, handler)
def remove_handler(self, event: ProviderEvent, handler: EventHandler) -> None:
_event_support.remove_client_handler(self, event, handler)
def _typecheck_flag_value(
value: typing.Any, flag_type: FlagType
) -> typing.Optional[OpenFeatureError]:
type_map: TypeMap = {
FlagType.BOOLEAN: bool,
FlagType.STRING: str,
FlagType.OBJECT: (dict, list),
FlagType.FLOAT: float,
FlagType.INTEGER: int,
}
_type = type_map.get(flag_type)
if not _type:
return GeneralError(error_message="Unknown flag type")
if not isinstance(value, _type):
return TypeMismatchError(f"Expected type {_type} but got {type(value)}")
return None