transformer_factory
trestle.transforms.transformer_factory
¤
Define the TransformerFactory and corresponding transformer classes it creates.
Classes¤
FromOscalTransformer (TransformerBase)
¤
Abstract interface for transformers from OSCAL.
Source code in trestle/transforms/transformer_factory.py
class FromOscalTransformer(TransformerBase):
"""Abstract interface for transformers from OSCAL."""
@abstractmethod
def transform(self, obj: OscalBaseModel) -> str:
"""Transform the from OSCAL."""
ResultsTransformer (TransformerBase)
¤
Abstract interface for transformers that specifically return Results.
Source code in trestle/transforms/transformer_factory.py
class ResultsTransformer(TransformerBase):
"""Abstract interface for transformers that specifically return Results."""
@abstractmethod
def transform(self, blob: str) -> Results:
"""Transform the blob into Results."""
ToOscalTransformer (TransformerBase)
¤
Abstract interface for transformers to OSCAL.
Source code in trestle/transforms/transformer_factory.py
class ToOscalTransformer(TransformerBase):
"""Abstract interface for transformers to OSCAL."""
@abstractmethod
def transform(self, obj: str) -> OscalBaseModel:
"""Transform the to OSCAL."""
TransformerBase (ABC)
¤
Abstract base interface for all transformers.
Source code in trestle/transforms/transformer_factory.py
class TransformerBase(ABC):
"""Abstract base interface for all transformers."""
# the current time for consistent timestamping
_timestamp = datetime.datetime.utcnow().replace(microsecond=0).replace(tzinfo=datetime.timezone.utc).isoformat()
@staticmethod
def set_timestamp(value: str) -> None:
"""Set the default timestamp value."""
datetime.datetime.strptime(value, '%Y-%m-%dT%H:%M:%S%z')
TransformerBase._timestamp = value
@staticmethod
def get_timestamp() -> str:
"""Get the default timestamp value."""
return TransformerBase._timestamp
@abstractmethod
def transform(self, blob: Any) -> Any:
"""Transform the blob into a general OscalBaseModel."""
Methods¤
get_timestamp()
staticmethod
¤
Get the default timestamp value.
Source code in trestle/transforms/transformer_factory.py
@staticmethod
def get_timestamp() -> str:
"""Get the default timestamp value."""
return TransformerBase._timestamp
set_timestamp(value)
staticmethod
¤
Set the default timestamp value.
Source code in trestle/transforms/transformer_factory.py
@staticmethod
def set_timestamp(value: str) -> None:
"""Set the default timestamp value."""
datetime.datetime.strptime(value, '%Y-%m-%dT%H:%M:%S%z')
TransformerBase._timestamp = value
transform(self, blob)
¤
Transform the blob into a general OscalBaseModel.
Source code in trestle/transforms/transformer_factory.py
@abstractmethod
def transform(self, blob: Any) -> Any:
"""Transform the blob into a general OscalBaseModel."""
TransformerFactory
¤
Perform registration and creation of transformers.
Source code in trestle/transforms/transformer_factory.py
class TransformerFactory:
"""Perform registration and creation of transformers."""
def __init__(self) -> None:
"""Initialize the transformers dictionary as empty."""
self._transformers: Dict[str, Type[TransformerBase]] = {}
def register_transformer(self, name: str, transformer: Type[TransformerBase]) -> None:
"""
Register the transformer.
This registers transformers in the factory so they may be created by name.
Args:
name (str): The name of the transformer.
transformer (TransformerBase): The transformer class to be registered.
Returns:
None
"""
self._transformers[name] = transformer
def get(self, name: str) -> TransformerBase:
"""
Create an instance of the desired transformer based its name.
Args:
name (str): The name of the transformer.
Returns:
An instance of the desired transformer.
Raises:
TrestleError: if the name does not exist in the registry.
"""
t = self._transformers.get(name)
if t is not None:
return t()
raise TrestleError(f'Error getting non-registered transform {name}')
Methods¤
__init__(self)
special
¤
Initialize the transformers dictionary as empty.
Source code in trestle/transforms/transformer_factory.py
def __init__(self) -> None:
"""Initialize the transformers dictionary as empty."""
self._transformers: Dict[str, Type[TransformerBase]] = {}
get(self, name)
¤
Create an instance of the desired transformer based its name.
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
name |
str |
The name of the transformer. |
required |
Returns:
| Type | Description |
|---|---|
TransformerBase |
An instance of the desired transformer. |
Exceptions:
| Type | Description |
|---|---|
TrestleError |
if the name does not exist in the registry. |
Source code in trestle/transforms/transformer_factory.py
def get(self, name: str) -> TransformerBase:
"""
Create an instance of the desired transformer based its name.
Args:
name (str): The name of the transformer.
Returns:
An instance of the desired transformer.
Raises:
TrestleError: if the name does not exist in the registry.
"""
t = self._transformers.get(name)
if t is not None:
return t()
raise TrestleError(f'Error getting non-registered transform {name}')
register_transformer(self, name, transformer)
¤
Register the transformer.
This registers transformers in the factory so they may be created by name.
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
name |
str |
The name of the transformer. |
required |
transformer |
TransformerBase |
The transformer class to be registered. |
required |
Returns:
| Type | Description |
|---|---|
None |
None |
Source code in trestle/transforms/transformer_factory.py
def register_transformer(self, name: str, transformer: Type[TransformerBase]) -> None:
"""
Register the transformer.
This registers transformers in the factory so they may be created by name.
Args:
name (str): The name of the transformer.
transformer (TransformerBase): The transformer class to be registered.
Returns:
None
"""
self._transformers[name] = transformer
handler: python