from collections import (
OrderedDict,
)
from collections.abc import (
Hashable,
)
from typing import (
Any,
Callable,
Dict,
Iterator,
List,
Mapping,
MutableMapping,
Optional,
Sequence,
Tuple,
Type,
TypeVar,
Union,
cast,
)
from eth_utils import (
is_integer,
)
from web3._utils.formatters import (
recursive_map,
)
# Hashable must be immutable:
# "the implementation of hashable collections requires that a
# key's hash value is immutable"
# https://docs.python.org/3/reference/datamodel.html#object.__hash__
T = TypeVar("T")
TKey = TypeVar("TKey", bound=Hashable)
TValue = TypeVar("TValue")
class ReadableAttributeDict(Mapping[TKey, TValue]):
"""
The read attributes for the AttributeDict types
"""
def __init__(
self, dictionary: Dict[TKey, TValue], *args: Any, **kwargs: Any
) -> None:
# type ignored on 46/50 b/c dict() expects str index type not TKey
self.__dict__ = dict(dictionary) # type: ignore
self.__dict__.update(dict(*args, **kwargs))
def __getitem__(self, key: TKey) -> TValue:
return self.__dict__[key] # type: ignore
def __iter__(self) -> Iterator[Any]:
return iter(self.__dict__)
def __len__(self) -> int:
return len(self.__dict__)
def __repr__(self) -> str:
return self.__class__.__name__ + f"({self.__dict__!r})"
def _repr_pretty_(self, builder: Any, cycle: bool) -> None:
"""
Custom pretty output for the IPython console
https://ipython.readthedocs.io/en/stable/api/generated/IPython.lib.pretty.html#extending # noqa: E501
"""
builder.text(self.__class__.__name__ + "(")
if cycle:
builder.text("<cycle>")
else:
builder.pretty(self.__dict__)
builder.text(")")
@classmethod
def _apply_if_mapping(cls: Type[T], value: TValue) -> Union[T, TValue]:
if isinstance(value, Mapping):
# error: Too many arguments for "object"
return cls(value) # type: ignore
else:
return value
@classmethod
def recursive(cls, value: TValue) -> "ReadableAttributeDict[TKey, TValue]":
return recursive_map(cls._apply_if_mapping, value)
class MutableAttributeDict(
MutableMapping[TKey, TValue], ReadableAttributeDict[TKey, TValue]
):
def __setitem__(self, key: Any, val: Any) -> None:
self.__dict__[key] = val
def __delitem__(self, key: Any) -> None:
del self.__dict__[key]
class AttributeDict(ReadableAttributeDict[TKey, TValue], Hashable):
"""
This provides superficial immutability, someone could hack around it
"""
def __setattr__(self, attr: str, val: TValue) -> None:
if attr == "__dict__":
super().__setattr__(attr, val)
else:
raise TypeError(
"This data is immutable -- create a copy instead of modifying"
)
def __delattr__(self, key: str) -> None:
raise TypeError("This data is immutable -- create a copy instead of modifying")
def __hash__(self) -> int:
return hash(tuple(sorted(tupleize_lists_nested(self).items())))
def __eq__(self, other: Any) -> bool:
if isinstance(other, AttributeDict):
return hash(self) == hash(other)
elif isinstance(other, Mapping):
return self.__dict__ == dict(other)
else:
return False
def tupleize_lists_nested(d: Mapping[TKey, TValue]) -> AttributeDict[TKey, TValue]:
"""
Unhashable types inside dicts will throw an error if attempted to be hashed.
This method converts lists to tuples, rendering them hashable.
Other unhashable types found will raise a TypeError
"""
def _to_tuple(value: Union[List[Any], Tuple[Any, ...]]) -> Any:
return tuple(_to_tuple(i) if isinstance(i, (list, tuple)) else i for i in value)
ret = dict()
for k, v in d.items():
if isinstance(v, (list, tuple)):
ret[k] = _to_tuple(v)
elif isinstance(v, Mapping):
ret[k] = tupleize_lists_nested(v)
elif not isinstance(v, Hashable):
raise TypeError(f"Found unhashable type '{type(v).__name__}': {v}")
else:
ret[k] = v
return AttributeDict(ret)
class NamedElementOnion(Mapping[TKey, TValue]):
"""
Add layers to an onion-shaped structure. Optionally, inject to a specific layer.
This structure is iterable, where the outermost layer is first, and innermost
is last.
"""
def __init__(
self,
init_elements: Sequence[Any],
valid_element: Callable[..., bool] = callable,
) -> None:
self._queue: "OrderedDict[Any, Any]" = OrderedDict()
for element in reversed(init_elements):
if valid_element(element):
self.add(element)
else:
self.add(*element)
def add(self, element: TValue, name: Optional[TKey] = None) -> None:
if name is None:
name = cast(TKey, element)
if name in self._queue:
if name is element:
raise ValueError("You can't add the same un-named instance twice")
else:
raise ValueError(
"You can't add the same name again, use replace instead"
)
self._queue[name] = element
def inject(
self, element: TValue, name: Optional[TKey] = None, layer: Optional[int] = None
) -> None:
"""
Inject a named element to an arbitrary layer in the onion.
The current implementation only supports insertion at the innermost layer,
or at the outermost layer. Note that inserting to the outermost is equivalent
to calling :meth:`add` .
"""
if not is_integer(layer):
raise TypeError("The layer for insertion must be an int.")
elif layer != 0 and layer != len(self._queue):
raise NotImplementedError(
f"You can only insert to the beginning or end of a {type(self)}, "
f"currently. You tried to insert to {layer}, but only 0 and "
f"{len(self._queue)} are permitted. "
)
self.add(element, name=name)
if layer == 0:
if name is None:
name = cast(TKey, element)
self._queue.move_to_end(name, last=False)
elif layer == len(self._queue):
return
else:
raise AssertionError(
"Impossible to reach: earlier validation raises an error"
)
def clear(self) -> None:
self._queue.clear()
def replace(self, old: TKey, new: TKey) -> TValue:
if old not in self._queue:
raise ValueError(
"You can't replace unless one already exists, use add instead"
)
to_be_replaced = self._queue[old]
if to_be_replaced is old:
# re-insert with new name in old slot
self._replace_with_new_name(old, new)
else:
self._queue[old] = new
return to_be_replaced
def remove(self, old: TKey) -> None:
if old not in self._queue:
raise ValueError("You can only remove something that has been added")
del self._queue[old]
@property
def middlewares(self) -> Sequence[Any]:
"""
Returns middlewares in the appropriate order to be imported into a new Web3
instance (reversed _queue order) as a list of (middleware, name) tuples.
"""
return [(val, key) for key, val in reversed(self._queue.items())]
def _replace_with_new_name(self, old: TKey, new: TKey) -> None:
self._queue[new] = new
found_old = False
for key in list(self._queue.keys()):
if not found_old:
if key == old:
found_old = True
continue
elif key != new:
self._queue.move_to_end(key)
del self._queue[old]
def __iter__(self) -> Iterator[TKey]:
elements = self._queue.values()
if not isinstance(elements, Sequence):
# type ignored b/c elements is set as _OrderedDictValuesView[Any] on 210
elements = list(elements) # type: ignore
return iter(reversed(elements))
def __add__(self, other: Any) -> "NamedElementOnion[TKey, TValue]":
if not isinstance(other, NamedElementOnion):
# you can only combine with another ``NamedElementOnion``
return NotImplemented
combined = self._queue.copy()
combined.update(other._queue)
return NamedElementOnion(cast(List[Any], combined.items()))
def __contains__(self, element: Any) -> bool:
return element in self._queue
def __getitem__(self, element: TKey) -> TValue:
return self._queue[element]
def __len__(self) -> int:
return len(self._queue)
def __reversed__(self) -> Iterator[TValue]:
elements = cast(List[Any], self._queue.values())
if not isinstance(elements, Sequence):
elements = list(elements)
return iter(elements)